Hematopathology Case Study: A 56 Year Old Man with Sinus Congestion and Axillary Adenopathy

Case History

A 56 year old male presented to his PCP complaining of sinus congestion, rhinorrhea, night sweats, decreased appetite and fevers of up to 101-102 every evening. Hematologic evaluation revealed a neutropenia and a lymphopenia. An infectious disease work up was negative. His LDH was elevated. Physical examination reveals an enlarged left axillary lymph node. An excisional biopsy was performed.

Biopsy Findings

Figure 1.jpg

Figure 2.jpg

H&E stained sections demonstrate an enlarged node with effaced architecture and scattered residual follicles with small, mature cells. There is a proliferation of intermediate to large, to very large, atypical and highly pleomorphic cells many of which demonstrate bizarre forms, irregular nuclear morphology and acidophilic nucleoli. The lymphoma cells are noted to focally traverse through adipose tissue. Occasional hallmark cells are appreciated.

To further characterize the infiltrate, immunohistochemical stains were performed and interpreted with appropriate controls. The lymphoma cells were diffusely positive for CD45 (LCA), CD43, and CD30 (membranous and Golgi) with a Ki-67 of 80-90%. These cells were negative for CD20, PAX-5, CD3, CD4, CD8 (mostly), CD5, D10, BCl-2, BCl-6 and ALK1.

The morphologic features and immunophenotype of the cells was diagnostic of anaplastic large cell lymphoma, ALK negative.

Discussion

Anaplastic Large Cell Lymphoma (ALCL), ALK-negative (ALK-) is defined as a CD30+ T-cell neoplasm that morphologically resembles ALK-positive ALCL, but lacks ALK protein expression. It most commonly affects adults (aged 40-65 years), and has a slight male preponderance with a male-to-female ratio of 1.5:1. T. Most patients present with advanced disease (stage III-IV), lymphadenopathy and B symptoms. The most common differential diagnosis is ALK-positive ALCL.

The molecular deciphering of ALCL began in the 1990s with the discovery of a recurrent t(2;5) (p23;q35) translocation fusing the ALK gene and the nucleophosmin gene generating a NPM-ALK fusion protein, as well as other ALK translocations resulting in a high ALK kinase activity. This triggers the major oncogenic pathway in ALK-positive ALCL. Pharmacologic therapy has been developed to target ALK, and has shown efficacy. Thus, compared with ALK-negative cases, ALK-positive occurs in younger patients and has a better prognosis. ALK-negative ALCL also tends to involve both lymph nodes and extranodal tissues, although extranodal sites are less commonly involved than in ALK+ ALCL.

The other differential diagnoses of ALK- ALCL includes, primary cutaneous ALCL (C-ALCL), other subtypes of CD30+ T-cell or B-cell lymphoma with anaplastic features and classic Hodgkin Lymphoma. If a single lymph node or cutaneous cases are suggestive of ALK- ALCL, C-ALCL needs to be considered. Any cases that involve the gastrointestinal tract need to be distinguished from CD30+ enteropathy-associated and other intestinal T-cell lymphomas.

Molecular analysis of ALK- ALCL shows characteristic strong expression of CD30, in equal intensity in all the cells. Loss of T-cell markers is frequently seen, however, more than half of all cases express one or more T-cell markers. CD2 and CD3 are more commonly expressed than CD5, and CD43 is almost always expressed. CD4+ is frequently positive, while CD8+ is rare. Many cases also express cytotoxic markers TIA1, granzyme B, and/or perforin.

The genetic profile in ALK-negative ALCL has been found to be pretty heterogenous. Most notably, activating mutations of JAK1 and/or STAT3 have been shown to lead to activation of the JAK/STAT3 pathway. Chromosomal rearrangements of DUSP22 (i.e. chromosomal rearrangements in or near the DUSP22-IRF4 locus on 6p25.3) occur in 30% of the cases, and rearrangements of TP63 occur in about 8% of cases. Neither of the rearrangements have been reported in ALK+ ALCL.

From a prognostic standpoint, studies have shown that the rearrangements have effects on the survival rate. TP63-rearranged cases were shown to have an unfavorable prognosis worse than ALK- ALCL with neither rearrangement, while DUSP22-rearranged cases were shown to have favorable outcomes similar to ALK-positive ALCLs.

References

  1. Gaulard P, de Leval L. ALK-negative anaplastic large-cell lymphoma. 2016 Jan 14;127(2):175-7.
  1. Edgardo R. Parrilla Castellar et al., ALK-negative anaplastic large cell lymphoma is a genetically heterogeneous disease with widely disparate clinical outcomes Blood. 2014 Aug 28; 124(9): 1473–1480.

 

Bradon Zelman

-Brandon Zelman is 4th year medical student at the Philadelphia College of Osteopathic Medicine and an aspiring pathologist. You can follow Brandon on Twitter @ZelmanBrandon.

Mirza-small

-Kamran M. Mirza, MD PhD is an Assistant Professor of Pathology and Medical Director of Molecular Pathology at Loyola University Medical Center. He was a top 5 honoree in ASCP’s Forty Under 40 2017. Follow Dr. Mirza on twitter @kmirza.

Hematopathology Case Study: A Newborn Infant with a High White Blood Cell Count

Case History

The patient is a 1 day old baby boy born at 39 weeks to a 44 year old woman. On physical examination, the baby had a mildly flattened occiput with thickened nuchal skin, downward slant of palpebral fissures with epichanthal folds and slightly low set ears. On imaging, he had a ventricular septal defect. A CBC was performed which revealed a white count of 34.2 K/uL with a differential that included 37 blasts.

Peripheral Blood Smear 

TAM1.jpg

TAM2

Cytogenetics

TAM3

TAM4.JPG

Diagnosis

The peripheral blood showed an increased white count, many nucleated red blood cells as well as a population of blasts. The cytogenetic analysis confirmed the suspicion of trisomy 21. Flow cytometry showed that the population of blasts expressed myeloid as well as erythroid and megakaryocytic lineage specific antigens. The patient was found to have a GATA1 mutation. Approximately one month after birth, the patient’s white count normalized to 7.2 K/uL with only 4 circulating blasts counted.

Discussion

In a patient with trisomy 21, this presentation is consistent with a diagnosis of transient abnormal myelopoiesis associated with Down syndrome (TAM). TAM occurs in 10% of newborns with Down syndrome. Patients typically present with cytopenias, leukocytosis, an increase in blasts and hepatosplenomegaly. Less commonly, patients can have respiratory distress, bleeding, skin rash or jaundice. The blasts are morphologically and immunophenotypically similar to those seen in acute myeloid leukemia. They often have basophilic cytoplasm, coarse basophilic granules and cytoplasmic blebbing, which suggests a megakaryocytic lineage. The immunophenotype generally includes expression of myeloid markers such as CD117, CD13 and CD33 plus erythroid and megakaryocytic markers like CD41, CD42b and CD61.1

In addition to trisomy 21, mutations in GATA1 are almost always seen in the blast cells of patients with TAM. GATA1 is a hematopoetic transcription factor. Bhatnagar, et al. (see diagram below) describe a three step model to explain the evolution of TAM. The initial event is abnormal hematopoesis in the fetal liver caused by trisomy 21. This causes an increase in megakaryocyte-erythroid progenitors in the hematopoetic stem cell compartment.  The second step is the acquisition of an N-terminal truncating GATA1 mutation before birth. GATA1 is a regulator of normal megakaryocyte and erythroid differentiation. The truncated mutation causes marked expansion of megakaryoblastic progenitors.

TAM5TAM has a high rate of spontaneous remission and typically resolves spontaneously in 90% of patients over several weeks to 6 months. This coincides with extinction of the GATA1 clone. However, in around 10% of these patients, myeloid leukemia of Down syndrome (ML-DS) develops within 5 years of the initial presentation. Additional mutations in cohesion component genes and epigenetic regulators occur in these patients that result in clonal expansion and non-transient leukemia. 2 Children who develop ML-DS generally have a good response to chemotherapy and a have a better prognosis than children without Down syndrome who develop AML.

References

  1. Swerdlow SH, Campo E, Harris NL, et al. WHO Classification of Tumours of Haematopoetic and Lymphoid Tissues (Revised 4th edition). IARC: Lyon 2017.
  2. Bhatnagar, Neha et al. “Transient Abnormal Myelopoiesis and AML in Down Syndrome: An Update.” Current Hematologic Malignancy Reports5 (2016): 333–341. PMC. Web. 21 Oct. 2018.

 

Marcus, Chelsea_099-Edit

Chelsea Marcus, MD is a third year resident in anatomic and clinical pathology at Beth Israel Deaconess Medical Center in Boston, MA and will be starting her fellowship in Hematopathology at BIDMC in July. She has a particular interest in High-grade B-Cell lymphomas and the genetic alterations of these lymphomas.

 

 

Hematopathology Case Study: A 63 Year Old Man with Fatigue

Case history

A 63 year old male presented with extreme fatigue and weakness of unknown duration. Physical examination revealed scattered petechiae and mildly decreased muscle strength. His past medical history included a one year history of cough that had recently improved. Laboratory investigation demonstrated severe anemia and thrombocytopenia with a mild leukopenia.

Review of the peripheral blood smear showed smudge cells, circulating neutrophils with Döhle bodies and toxic granulation. CT scan of the chest showed upper/anterior mediastinal lymphadenopathy without hilar lymphadenopathy.

A biopsy of the bone marrow was performed.

Microscopic Findings

hod1.jpg

 

hod 2.jpg

The bone core biopsy revealed a hypercellular marrow for the patient’s age with a pronounced lymphohistiocytic infiltrate involving 30-40% of the biopsied marrow space. Interspersed along the infiltrate were large, atypical lymphoid cells with pleomorphic nuclei and prominent nucleoli. The marrow aspirate smear reveals progressive trilineage hematopoiesis with scattered hemophagocytic histiocytes.

Immunophenotype

hod3.jpg

The large atypical lymphoid cells were positive for CD30 and EBER, while being dimly positive for PAX5 and negative for CD20.

Diagnosis

The detection of mononuclear Hodgkin cells staining for CD30 along with a characteristic reactive infiltrate, together with dim PAX-5 staining, positive EBER, and negative CD20 is sufficient to diagnose involvement of a secondary site by Hodgkin lymphoma. The lymphoma was associated with a secondary hemophagocytic lymphohistiocytosis.

Discussion

Hodgkin lymphoma (HL) is a B-cell derived monoclonal lymphoid neoplasm. HL has a bimodal age distribution, with teenagers or patients in their early 20s and patients older than 55 years having the highest incidence. Although the typical presentation is with peripheral lymph node involvement, extranodal sites may be involved by either direct invasion or hematogenous dissemination. These sites include the spleen, liver, lung and bone marrow. About one third of patients have constitutional symptoms such as high fevers, night sweats, and weight loss.

Two broader forms of Hodgkin lymphoma exist: Classic Hodgkin lymphoma (CHL) and the less common nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL). NLPHL tends to preserve the entire B-cell transcriptional phenotype, while the neoplastic cells in CHL fail to do so.

CHL is composed of mononuclear Hodgkin cells and multinucleated Reed-Sternberg cells surrounded by an infiltrate of non-neoplastic reactive cells that might encompass small lymphocytes, plasma cells, eosinophils, neutrophils, and histiocytes. Fibrosis may also be present in the form of bands or may be more diffusely spread. The four histological subtypes: nodular sclerosis CHL, lymphocyte-rich CHL, mixed cellularity CHL, and lymphocyte-depleted CHL are based on the composition and characteristic of the reactive infiltrate, and the cytological features of the neoplastic cells.

The classic Reed-Sternberg cell is binucleated, with prominent eosinophilic nucleoli, often referred to as having an “owl’s eye” appearance. However many neoplastic cells are not of the typical Reed-Sternberg variant, and can be mononuclear, termed Hodgkin cells, or cells with more condensed cytoplasm and pyknotic reddish nuclei known as mummified cells.

Hodgkin/Reed-Sternberg cells (HRS) in Classic Hodgkin Lymphoma fail to preserve their B-cell traits, and this is reflected by their immunophenotype. The majority of cases are negative for CD45, and although CD20 may be expressed, it is usually present only on a minority of the neoplastic cells and stain with varied intensity. The HRS cells stain with PAX5 with a lower intensity than the surrounding reactive cells, making them easily detectable. The HRS cell stains positive for CD30 and CD15 in nearly all cases. Both of them stain the membrane with accentuation around the Golgi apparatus. EBV associated Hodgkin Lymphoma will stain positive with EBER, detecting EBV-encoding small RNA.

Bone marrow involvement is rare, ~5-10% of cases, and suggest vascular dissemination of the disease. Bone marrow trephine biopsies are commonly performed in the staging of patients with newly diagnosed CHL which guides the further treatment and gives us information about prognosis. Involvement of the bone marrow represents stage IV disease (advanced stage) in the Ann Arbor staging classification and patients with advanced stage disease typically receive a more prolonged course of chemotherapy. The 5-year survival rate of stage IV Hodgkin lymphoma is ~65%,  a much worse prognosis when compared with stage I, stage II, and stage III with ~90%, ~90%, and ~80% 5-year survival rates respectively.

References

  1. Stein H, Pileri SA, Weiss LM, et al. Hodgkin Lymphomas. In Swerdlow SH, Campo E, Harris NL, Jaffe ES, Pileri SA, Stein H, Thiele J, editors: WHO classification of tumours of haematopoietic and lymphoid tissues, revised ed 4, Lyon, France, 2017, IARC Press, pp 423-464
  2. Ansell SM. Hodgkin Lymphoma: Diagnosis and Treatment. Mayo Clin Proc. 2015 Nov;90(11):1574-83.
  3. Howell SJ, Grey M, Chang J, Morgenstern GR, Cowan RA, Deakin DP, Radford JA. The value of bone marrow examination in the staging of Hodgkin’s lymphoma: a review of 955 cases seen in a regional cancer centre. Br J Haematol. 2002 Nov;119(2):408-11.
  4. Clarke C, O’Malley C, Glaser S. Hodgkin lymphoma. In: Ries LAG, Young JL, Keel GE, Eisner MP, Lin YD, Horner M-J, eds. SEER Survival Monograph: Cancer Survival Among Adults: U.S. SEER Program, 1988-2001, Patient and Tumor Characteristics. National Cancer Institute, SEER Program, NIH Pub. No. 07-6215, Bethesda, MD, 2007.

 

Hans.jpg

-Hans Magne is a 6th- year medical student at Poznan University of Medical Sciences. Follow Hans on Twitter @HHamnvag

Mirza-small

-Kamran M. Mirza, MD PhD is an Assistant Professor of Pathology and Medical Director of Molecular Pathology at Loyola University Medical Center. He was a top 5 honoree in ASCP’s Forty Under 40 2017. Follow Dr. Mirza on twitter @kmirza.

Hematopathology Case Study: The Case of Lymphocytosis

Case History

53 year old female was found to have leukocytosis upon a wellness examination. A CBC was performed and found a WBC of 34.0, HgB 13.2, and Plt of 263,000. The WBC differential consisted of 80% Lymphocytes and 12% neutrophils. The patient states that she is feeling well, no fever, chills, or night sweats. She denies any adenopathy. Flow Cytometry was recommended as well as morphologic review along with Cytogenetics and FISH (fluorescence in-situ hybridization).

Lab Identification

CBC

WBC               33.68  [103/uL] NEUT             4.17 [103/uL]      12.3 [%]
RBC                4.54  [106/uL] LYMPH          26.91 [103/uL]    79.9 [%]
HGB               13.2   [g/dL] MONO           2.04 [103/uL]      6.1  [%]
HCT               40.0   [%] EO                  0.39 [103/uL]      1.2  [%]
MCV               88.1   [fL] BASO             0.11 [103/uL]      0.2  [%]
MCH               29.1   [pg] IG                    0.06 [103/uL]      0.2  [%]
MCHC            33.0   [g/dL] NRBC             0.00 [103/uL]      0.0  [%]
RDW-CV         14.3   [%]
PLT                263   [103/uL]
MPV                9.4   [fL]

Morphologic Review

CLL1.jpg
Image 1. 40x magnification showing lymphocytosis.
CLL2.jpg
Image 2. 60x magnification showing lymphocytosis with occasional smudge cells.

Flow Cytometry: Population of Interest – Abnormal Lymphocytes

cll3.JPG

cll4.JPG

cll5.JPG

Cytogenetics: 46,XX[20] Normal Female Karyotype

It is not unusual to observe a normal karyotype in CLL due to the limited number of abnormal cells and/or low spontaneous proliferative activity of the malignant cells. Fluorescence in situ hybridization studies may identify cytogenetic abnormalities of prognostic significance in interphase nuclei not observed in the metaphase cells analyzed. In cases of CLL molecular profiling may be performed to aid in predicting course of the disease. If clinically indicated these studies may be considered. Standard cytogenetic analysis may not detect subtle submicroscopic rearrangements and may not include metaphases from abnormal cell populations with low mitotic rates or present in low levels.

Metaphases Counted: 20 Metaphases Analyzed: 20
Metaphases Karyotyped: 2 Culture Type: 48EB, 72IL2/DSP30
Banding Technique: GTG Banding Resolution: 400

Fluorescence in-situ Hybridization: Abnormal – 13q14 deletion present

Fluorescence in situ hybridization (FISH) analysis was performed using a specific set of probes for Chronic Lymphocytic Leukemia (CLL). This study revealed a 13q14 deletion. Counts for all other probes were within the normal reference range. This finding represents an ABNORMAL result. Deletion of 13q14 is the most common deletion in CLL being reported in 10-20% of cases by conventional cytogenetics and up to 64% of cases by FISH analysis. When present as a sole abnormality this deletion is associated with a good prognosis and a median survival longer than CLL patients with a normal karyotype.

Del(6q) Not Detected
Del(11q)(ATM) Not Detected
Trisomy 12 Not Detected
Del(13q)/-13 DETECTED
t(11;14) Not Detected
Del(17p)(TP53) Not Detected

Discussion

Chronic Lymphocytic Leukemia is a neoplasm of about 5 cases per 100,000 people with a median age of around 70 years old. The neoplasm is composed of monotypic mature B-cells that typical express CD5. Other immunophenotypic characteristics of the leukemic B-cells include CD19, CD20, CD22, and CD79b with dim surface expression of one of the immunoglobulin light chains, Kappa or Lambda. These cells typically express CD200 which helps differentiate the leukemia from Mantle Cell Lymphoma/Leukemia. Patients found to have a mutated IGHV genes typically have a better prognosis than those with an unmutated genes. Expression of ZAP70, CD38, or CD49d is also associated with an adverse prognosis. Complex karyotypes also trend towards a poor outcome. Adverse predictive factors include rapid lymphocyte proliferations in the blood, typically doubling in < 12 months.

Monoclonal B-cell Lymphocytosis is typically characterized as a monoclonal
BCell count of <5 X109/L in the peripheral blood. Monoclonal B-cell Lymphocytosis with a Chronic Lymphocytic Leukemia-type phenotype is the most common which accounts for about 75% of all cases. It has been reported that virtually all Chronic Lymphocytic Leukemias are preceded by Monoclonal B-cell Lymphocytosis, although not all MBLs progress to CLL.

References

  1. Dohner H, et al. N Engl J Med 2000; 343:1910-6.
  2. Hamblin TJ.Best Practice & Research Clinical Haematology. 2007; 20(3):455 – 68.
  3. Swerdlow SH, Campo E, Harris NL, Jaffe ES, Pileri SA, Stein H. WHO classification of tumours of haematopoietic and lymphoid tissues, fourth edition. Lyon, France: IARC; 2017
  4. Nowakowski GS, et al. Br J Hematol. 2005; 130:36 – 42.
  5. Atlas of Genetics and Cytogenetics in Oncology and Hematology http://atlasgeneticsoncology.org/

 

Troy-Krieger-small

Troy G. Krieger, MS, MLS(ASCP)CMSCYMCMQLSCMCLS(MT) graduated from Montana State University Billings with a BS in Biology, Medical Laboratory Science option. He received a NAACLS Certificate and clinical training from the University of North Dakota in Grand Forks, ND, where he also received his Master’s degree. He is a Medical Laboratory Scientist / Flow Cytometrist at Yellowstone Pathology Institute, Inc in Billings, MT and his interests include Hematology, Immunopathology, and Flow Cytometry.

Hematopathology Case Study: A 43 Year Old Man with History of Latent TB

Case History

43 year old Vietnamese speaking man with a history of treated latent TB who presented with one month of fevers, night sweats, weight loss, and acute left facial swelling with associated pain, nasal congestion and 2 nose bleeds. The patient was found to have a polypoid mass within the left interior nasal cavity.

Biopsy Left Nasal Mass

nkt-he10x
H&E 10x
nkt-he40x
H&E 40x
nkt-cd3
CD3
nkt-cd5
CD5
nkt-cd56
CD56
nkt-perforin
Perforin
nkt-67
KI-67
nkt-eber.jpg
EBER

Diagnosis

The biopsy shows nasal mucosa with a dense submucosal lymphoid infiltrate and large areas of necrosis. The lymphocytes are somewhat pleomorphic, medium to large in size with irregular nuclear contours, vesicular chromatin and inconspicuous nucleoli. There are scattered mitoses and apoptotic cells.

By immunohistochemistry, CD3 highlights the lymphoma cells, which comprise the majority of the lymphoid infiltrate. The lymphoma cells co-express CD56 and CD7 (dim) and are negative for CD2 and CD5. The lymphoma cells also express cytotoxic markers perforin and granzyme (major subset). CD20 highlights only rare small clusters of B-cells. The lymphoma cells are also positive for EBER (Epstein-Barr Virus encoded RNA) in situ hybridization.  The Ki67 (MIB1) proliferation index is 60% with focal areas exhibiting up to 80%.

Taken together, the morphologic and immunophenotypic findings are consistent with an extranodal NK/T cell lymphoma, nasal type.

Discussion

Extranodal NK/T cell lymphoma, nasal type is an aggressive lymphoma that is more prevalent in Asian and South American populations. It occurs most often in adults and is more common in men than women. It is generally located in the upper aerodigstive tract, with the nasal cavity being the prototypical site. Patients tend to present in a manner similar to the patient described in this case, with rhinorrhea, pain, nasal obstruction and epistaxis due to a mass lesion. 1 The term “lethal midline granuloma” was once used to describe this entity because patients can present with locally destructive mid-facial necrotizing lesions. The early non-specific symptoms can pose a diagnostic challenge, and often result in treatment delays, which makes the aggressive disease more lethal. 2

The entity is described as NK/T cell lymphoma because although most cases are of NK-cell origin, some cases are comprised of cytotoxic T-cells. Natural killer (NK) cells are non-T and non-B lymphocytes that are part of the innate immune system. They respond immediately to antigenic challenge and are able to directly kill virally infected cells without the help of antigen presenting cells. They also secrete cytokines to increase the innate immune response. NK cells are classically positive for cytoplasmic CD3 and CD56, as well as cytotoxic molecules granzyme and perforin. Of note, NK-cells lack recombination activating gene enzymes and therefore have no clonal molecular marker for gene rearrangement such as the T-cell receptor or Immunoglobulin heavy chain.  3

Microscopically, the involved sites generally have widespread mucosal destruction. There is an angioentric and angiodestructive growth pattern that results in extensive necrosis. Another important diagnostic consideration is the very strong association with EBV. EBV is present in a clonal episomal form. This means that the infection occurs prior to and likely plays a pathogenic role in the development of NK/T cell lymphomas. 3

Following diagnosis, staging and management of the disease involves quantification of circulating EBV DNA. This can be used as a laboratory marker for disease status and progression or remission of disease. PET/CT is performed for accurate staging and patients are most commonly treated with a combination of radiotherapy and the SMILE regimen, which includes dexamethasone, methotrexate, ifosfamide, L-asparaginase and etoposide. NK/T cell lymphomas are aggressive and patients tend to have a short survival and poor overall response to therapy. 3

A recent study by Kwong, et al. showed the potential use of PD1 (programmed death ligand 1) blockade drug pembrolizumab in the treatment of relapsed or refractory NK/T-cell lymphoma. As mentioned above, the lymphocytes in this entity are invariably infected with EBV. PD1 is known to be up regulated in cells infected with EBV. In the study, seven patients who had failed treatment with the SMILE regimen were treated with pembrolizumab. After a medium follow-up of 5 months, 5 patients remained in complete remission and all patients had objective responses to treatment. 4 This shows promise as a potential new treatment for patients with this uncommon, but deadly disease.

 

References

  1. Swerdlow SH, Campo E, Harris NL, et al. WHO Classification of Tumours of Haematopoetic and Lymphoid Tissues (Revised 4th edition). IARC: Lyon 2017.
  2. Mallya V, Singh A, Pahwa M. Lethal midline granuloma. Indian Dermatology Online Journal. 2013;4(1):37-39. doi:10.4103/2229-5178.105469.
  3. Tse, E, Kwong, Yok-Lam. The diagnosis and management of NK/T-cell lymphomas. Journal of Hematology and Oncology. 2017:10:85. Doi: 10.1186/s13045-017-0452-9.
  4. Yok-Lam, K, Thomas, S.Y. Chan, Daryl Tan, et. al. PD1 blockade with pembrolizumab is highly effective in relapsed or refractory NK/T-cell lymphoma failing L-asparaignase. Blood. 2017:129:2437-2422. Doi: 10/1182/blood-2016-12-758641.

 

Marcus, Chelsea_099-Edit

Chelsea Marcus, MD is a third year resident in anatomic and clinical pathology at Beth Israel Deaconess Medical Center in Boston, MA and will be starting her fellowship in Hematopathology at BIDMC in July. She has a particular interest in High-grade B-Cell lymphomas and the genetic alterations of these lymphomas.

Hematopathology Case Study: A 48 Year Old Woman with Left Upper Quadrant Pain

Case History

A 48-year-old female presents with a one-month history of left upper quadrant pain. Laboratory investigation reveals pancytopenia. Radiology work-up demonstrates splenomegaly. CT scan confirms splenomegaly at 22 cm. There is no lymphadenopathy appreciated in the abdomen. A bone marrow biopsy is performed.

Figure HSTCL
Image 1. H&E and CD3 stains at varying magnification.

Bone Marrow Findings

The bone marrow core biopsy reveals a normocellular marrow space (approximately 50% cellular marrow) with progressive trilineage hematopoiesis. Clusters of small, slightly irregular, mature-appearing lymphocytes are seen within the sinusoids. The marrow aspirate smears reveal mild erythroid hyperplasia without morphologic evidence of dysplasia. There is no increase in blasts. Lymphocytes comprise 18% of a 500-cell differential count on the marrow aspirate smears.

The sinusoidally distributed lymphocytes demonstrate immunopositivity (flow and/or IHC) for CD2, CD3, CD7, CD16, CD56, and γδ. These neoplastic lymphocytes are negative for granzyme B, CD4, CD5, CD8, CD57, and αβ.  PCR for T-cell receptor clonality was positive. Cytogenetics revealed a normal female karyotype. FISH for 5p/5q and 7p11/7q31 was normal.

Diagnosis

Taken together, the patient’s clinical presentation along with the presence of an abnormal gamma-delta population of T cells in a sinusoidal distribution with PCR evidence of T-cell clonality is diagnostic of a T-cell lymphoma. The pattern of distribution, granzyme B negativity, lack of concurrent adenopathy favor a diagnosis of Hepatosplenic T-cell lymphoma.

Discussion

Hepatosplenic T-cell lymphoma (HSTCL) is an uncommon entity that represents <1% of all non-Hodgkin lymphomas and 1%-2% of all T/natural killer cell lymphomas. It most commonly affects young adult men, with a median age of 35 years. This high-grade malignancy is most often characterized by γδ T-cells. The most consistent symptoms among patients are fever, splenomegaly, hepatomegaly, bone marrow involvement, peripheral blood cytopenia, and less commonly, adenopathy. Hepatosplenic T-cell lymphoma has a poor prognosis with median survival rates varying from a few months to 16 months in different studies.

Immune suppression (such as solid- organ transplant, or immune dysregulation secondary to malignancy or infection) is thought to play a role in the lymphomagenesis in around 20% of cases. Inflammatory bowel disease and the use of immunosuppressive agents (e.g., antitumor necrosis- α agents) and antimetabolite therapy (e.g., 6TG, 6MP) had also been associated with development of HSTCL.

HSTCL initially infiltrates the cords and sinusoids of the splenic red pulp. The white pulp is often atrophic or absent. Eventually, the neoplastic T cells diffusely replace the spleen. The lymphoma cells often involve the liver and bone marrow sinusoids. At the time of diagnosis, the bone marrow is almost always involved and commonly hypercellular. The neoplastic cells are mostly intermediate in size, with pale agranular cytoplasm and round nuclei with condensed chromatin and inconspicuous nucleoli.

Cytogenetic studies in HSTCL most commonly show isochromosome 7q and trisomy 8. Molecular analysis of HSTCL characteristically shows expression of a γδ T-cell type and flow cytometric analysis typically reveals a CD2+, CD3+, CD7+/−, CD4−, CD5−, and CD8− phenotype with positivity for natural killer cell-associated markers CD11b, CD16, and CD56.

Activating mutations in PI3KCD and STAT signaling genes have also been described in HSTCL, providing potential molecular target therapies for this aggressive lymphoma.

The differential diagnosis of HSTCL includes other types of T-cell lymphoma and leukemia, and non-neoplastic such as immune thrombocytopenia or acute hepatitis. In most instances, the distinctive presentation of spleen, liver and bone marrow involvement, the immunophenotype and T-cell monoclonality distinguishes HSTCL from other entities.

The outcomes of the patients using standard chemotherapy regimens are dismal, and allogeneic SCT appears to be a reasonable approach to achieve the best possible patient outcome.

References

  1. Yabe M, Miranda RN, Medeiros LJ. Hepatosplenic T-cell Lymphoma: a review of clinicopathologic features, pathogenesis, and prognostic factors. Hum Pathol. 2018 Apr; 74:5-16.
  2. McThenia SS, Rawwas J, Oliveira JL, Khan SP, Rodriguez V. Hepatosplenic γδ T-cell lymphoma of two adolescents: Case report and retrospective literature review in children, adolescents, and young adults. Pediatr Transplant. 2018 Aug;22(5): e13213.

 

levent photo

-Levent Trabzonlu, MD is a postdoctoral researcher in the department of pathology at Johns Hopkins University in Baltimore, MD. Follow Dr. Trabzonlu on twitter @aflevent

Mirza-small

-Kamran M. Mirza, MD PhD is an Assistant Professor of Pathology and Medical Director of Molecular Pathology at Loyola University Medical Center. He was a top 5 honoree in ASCP’s Forty Under 40 2017. Follow Dr. Mirza on twitter @kmirza.

Hematopathology Case Study: A 55 Year Old Woman with Fatigue, Nausea, and Vomiting

Case History

55 year old woman with no significant past medical history presented with two weeks of increasing fatigue, nausea and vomiting. She was subsequently found to have a leukocytosis (WBC = 31.1) and marked splenomegaly (19 cm).

Peripheral Blood

mcl-peri-1

mcl-peri-2

 

Bone Marrow Biopsy 

mcl-bm-20x
aspirate 20X
mcl-bm-40
aspirate 40X
mcl-bm-core-10
core biopsy 10X
mcl-bm-core-40
core biopsy 40X

 

mcl-core-cd20
core biopsy CD20
mcl-core-bcl1
core biopsy BCL1 (CCND1)

 

Flow Cytometry

mcl-flow

 

Cytogenetics

mcl-cyto-kary
Karyotype
mcl-cyto-IGH
IGH/CCND1 gene rearrangement
mcl-cyto-deletion
deletion of TP53
mcl-cyto-MYC
MYC amplification

 

Diagnosis

The peripheral blood shows a population of atypical cells that at first may look like blasts. However, the variable size, round to markedly irregular nuclear contours, large prominent nucleoli and mild to moderate amounts of cytoplasm favor lymphoma cells.

The bone marrow aspirate shows the vast majority of the cellularity is composed of a pleomorphic population of lymphoma cells that are varied in size from small to large with mild to moderate cytoplasm, round to irregular nuclear contours and prominent nucleoli. Occasional maturing erythroid and myeloid precursors are present.

The core biopsy shows a marrow with a cellularity of approximately 70%. There is an interstitial infiltrate of atypical mononuclear cells with frequent scattered mitoses occupying 70% of the overall cellularity. By immunohistochemistry performed on the core biopsy, B-cell marker CD20 highlights the majority of the infiltrating lymphocytes, which co-express BCL1 (CCND1).

Flow cytometry revealed a population of CD19 and CD20 positive kappa (bright) restricted B-cells that were also positive for CD23 in a subset. They did not express any other characteristic antigens including CD5, CD10 and CD11c. Importantly, as there was initial concern for acute myeloid or lymphoblastic leukemia, no abnormal events were identified in the CD45 dim “blast” gate, with CD34 positive blasts showing normal maturation.

Cytogenetics revealed a complex abnormal karyotype. The most important finding was a translocation involving the long arms of chromosome 11 and 14 resulting in the IGH/CCND1 translocation that is characteristic of mantle cell lymphoma. Interestingly, the FISH probe showed that there were 4 IGH/CCND1 fusions indicating an extra copy of the derivative chromosome 14. Additional FISH probes showed a deletion of the TP53 gene on 17p13 and greater than 10 copies of the MYC gene on chromosome 8, consistent with MYC amplification.

Overall, the findings are consistent with a pleomorphic variant of mantle cell lymphoma with leukemic peripheral blood involvement. The cytogenetic findings portend an unfavorable prognosis.

Discussion

Mantle cell lymphoma is generally characterized as an aggressive lymphoma of mature B-cells. It accounts for approximately 3-10% of non-Hodgkin lymphomas and tends to occur in older men. Lymph nodes are the most commonly involved site; however the bone marrow and peripheral blood are frequently involved as well. There are multiple morphologic variants of mantle cell lymphoma. The two aggressive variants include blastoid and pleomorphic. The blastoid variant has cells that resemble lymphoblasts with dispersed chromatin and large prominent nucleoli. The pleomorphic variant is characterized by a spectrum of cells, with many large cells with irregular nuclear contours, pale cytoplasm and variably prominent nucleoli. These two variants are clinically significant because they portend a worse prognosis. 1

The patient’s cytogenetic findings also portend a poor prognosis. IGH/CCND1 is a translocation between the immunoglobulin heavy chain on chromosome 14 and cyclin D1 on chromosome 11. This translocation leads to the overexpression of cyclin D1. However, Cyclin D1 is a “weak” oncogene and is not sufficient by itself to lead to the development of lymphoma. There are numerous secondary chromosomal aberrations and mutations that must occur to result in the presentation of mantle cell lymphoma. A paper by Beà et al. performed whole genome and/or whole exome sequencing on 29 cases of mantle cell lymphoma. They detected around 3,700 somatic mutations per tumor. ATM, CCND1 and TP53, which have previously been described as drivers in mantle cell lymphoma, were found frequently mutated. TP53 mutations were found in 28% of the lymphomas.2

MYC is a potent proto-oncogene located on chromosome 8. It mainly functions as a transcription factor and its activation leads to increased DNA replication, protein synthesis and alterations in cell metabolism among many other changes. The ultimate effect is increased cell proliferation and tumorigenesis. MYC amplification or translocation was shown to occur more often in blastoid/pleomorphic mantle cell lymphoma variants. This finding was associated with a shortened overall survival and progression-free survival. 3

References

  1. Swerdlow, Steven H. WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues. Revised 4th ed., International Agency for Research on Cancer, 2017.
  2. Beà S, Valdés-Mas R, Navarro A, et al. Landscape of somatic mutations and clonal evolution in mantle cell lymphoma. Proceedings of the National Academy of Sciences of the United States of America. 2013;110(45):18250-18255. doi:10.1073/pnas.1314608110.
  3. Choe, JY, Yun, JY, Na, HY, et al. MYC overexpression correlates with MYC amplification or translocation, and is associated with poor prognosis in mantle cell lymphoma. 2016 Feb;68(3):442-9. doi: 10.1111/his.12760. Epub 2015 Jul 28.

 

Marcus, Chelsea_099-Edit

Chelsea Marcus, MD is a third year resident in anatomic and clinical pathology at Beth Israel Deaconess Medical Center in Boston, MA and will be starting her fellowship in Hematopathology at BIDMC in July. She has a particular interest in High-grade B-Cell lymphomas and the genetic alterations of these lymphomas.