Case History

Case number: 00007

A young man with a known history of HIV infection presents with abdominal bloating. HIV was diagnosed many years ago, but the patient has defaulted follow-up and medication for the last two years. He has previously had a number of opportunistic infections. On examination, he has a low-grade fever and marked abdominal distension.

Investigations:
Hb 15.1 TW 4.0 Plt 405
Cr 178 CrCl 35
Alb 15 Bili 10 ALT 22 AST 88 ALP 41 GGT 16 Amylase 52

HIV viral load: 2,430,000 copies/ml (6.39 log)

A CT of the thorax, abdomen and pelvis showed a large, 10 x 8 x 5cm peritoneal soft tissue mass, inseparable from pancreatic body/neck. There was significant omental caking and peritoneal thickening with enhancement, with a moderate right pleural effusion.

He underwent a diagnostic thoracocentesis. The pleural fluid cell count showed 2285 RBCs and 6100 WBCs, comprising mostly large atypical lymphoid cells with basophilic cytoplasm and prominent nucleoli. The pleural fluid was processed as a cell block. On immunohistochemistry the cells were positive for CD79A, CD138 and EBER-ish. CD20, PAX5, HHV-8 and CD30 were negative. The Ki-67 proliferation index was > 90%.

Flow cytometry of the pleural fluid yielded the following immunophenotype: SSC-hi / CD45dim / smCD3- / CD19- / 20- / 38++ / 138+ / 5- / 81het / 117- / 27+ / 56het / cyKappa restricted / smkappa dim / 10- / 23- / 43+ / 79b- / 31+ / LAIR1- / 11c- / 103- / 95- / 22- / 49d- / 62l- / HLADR-

A bone marrow biopsy was done for staging purposes. Both the pleural fluid cytospins and the bone marrow aspirate are shown below.







Questions:

  1. How would you interpret the immunophenotype of the abnormal cell? What are the important positives and negatives?
  2. What is the diagnosis?
  3. How would you treat this patient?

Discussion