Hematopathology Case Study: A 39 Year Old Woman Presenting with Persistent Cough and Pericardial Effusion

Case history

The patient is a 39 year old woman presenting with a persistent cough. Upon work up, a pericardial effusion is noted. Pericardiocentesis is performed and a smear made from the pericardial fluid reveals atypical lymphoid cells.

Cytology of the Pericardial Fluid

Additional imaging reveals an anterior mediastinal mass measuring 12.6 cm. Excision of the mediastinal mass is performed. Sections of mediastinal mass show a variable population of lymphoid cells ranging from small to medium lymphocytes and some atypical large lymphocytes. These atypical large lymphocytes have irregular nuclear contours with abundant cytoplasm, vesicular chromatin and prominent nucleoli. These atypical large lymphoid cells are consistent with Hodgkin Reed-Sternberg cells. Abundant eosinophilic and scattered neutrophilic infiltration are noted within the nodules. These nodules are surrounded by dense collagen bands.

Immunohistochemistry studies are performed, atypical large lymphoid cells are positive for CD30, Fascin and PAX5, while rare small to medium sized lymphocytes are positive for CD20, however, large atypical lymphoma cells are negative for CD20. Tumor cells are negative for CD3, CD5, CD15, LCA, ALK and EBER ISH. CD3 and CD5 highlight the reactive T cells in the background.

Overall, the case is consistent with nodular sclerosis classic Hodgkin lymphoma.  The presence of sheets of large lymphoma cells is suggestive of the syncytial variant.

Discussion

Nodular sclerosis classic Hodgkin’s lymphoma (NSCHL) subtype has a distinct epidemiology, clinical presentation and histology. NSCHL is more common in females with peak aged between 15 and 34 years. The risk is higher in high socioeconomic status. The patients are presenting with particularly mediastinal mass and 40% B symptoms.

NSCHL can be distinguished from the other subtypes of Hodgkin’s lymphoma (HL) with characteristic histologic features. There is a nodular growth pattern and the nodules are surrounded by collagen bands representing nodular sclerosis.  The lymphoma is composed of variable number of Hodgkin Reed-Sternberg (HRS) cells, small to medium sized lymphoid cells and non-neoplastic inflammatory cells, predominantly eosinophils, neutrophils and histiocytes. HRS cells have multinucleated or binucleated with irregular nuclear contours and prominent nucleoli. HRS cells induce fibroblastic activity by expressing IL-13 and the fibrosis begins in the lymph node by invaginating into the lymph node along vascular septa.

Immunophenotypically, the lymphoma cells are mostly positive for CD30 and 75-85% positive for CD15. Association with EBV can be demonstrated with EBER in-situ hybridization.  The malignant lymphocytes in NSCHL are variably expressing CD20, PAX5 and CD79a, however, T cell antigen markers, particularly CD4 and CD2 are aberrantly expressed in NSCHL.

NSCHL is classified mostly as grade 2 and the prognosis is better than the other subtypes of HL.  Doxorubicin, bleomycin, vinblastine and dacarbazine (ABVD) is the most frequent induction regimen for NSCHL patients with over 70% response rate.

Patients with Syncytial Variant Nodular Sclerosis Classic Hodgkin Lymphoma experience a lower than expected rate of complete therapeutic response with shorter progression-free than non-SV NSCHL treated with standard therapy. Syncytial Variant NSCHL should therefore be recognized as a high-risk subgroup within the otherwise traditionally docile NSCHL classification. This case fits the classic presentation for syncytial variant with presentation as bulky (mediastinal) disease.

References

1. Eberle FC, Mani H, Jaffe ES. Histopathology of Hodgkin’s Lymphoma. Cancer J. 2009 Mar-Apr;15(2):129-37.
2. Swerdlow SH, Campo E, Harris NL et al. WHO Classification of Tumors of Haematopoietic and Lymphoid Tissues (Revised 4^th Edition). IARC: Lyon 2017.
3. Sethi T, Nguyen V, Li S, Morgan D, Greer J. Differences in outcome of patients with syncytial variant Hodgkin Lymphoma compared with typical nodular sclerosis Hodgkin Lymphoma. Ther Adv Hematol 2017, Vol. 8(1):13-20.

–Ayse Irem Kilic is a 2nd year AP/CP pathology resident at Loyola University Medical Center. Follow Dr. Kilic on twitter @iremessa.

–Kamran M. Mirza, MD, PhD, MLS(ASCP)CM is an Assistant Professor of Pathology and Medical Education at Loyola University Health System. A past top 5 honoree in ASCP’s Forty Under 40, Dr. Mirza was named to The Pathologist’s Power List of 2018. Follow him on twitter @kmirza