Plasma cell leukemia: A case series from South India with emphasis on rarer variants

Primary Plasma Cell Leukaemia: Case report and review of the literature

Plasma cell leukaemia (PCL) is one of the most aggressive and rarest forms of plasma cell dyscrasia. However, the diagnostic criteria for this condition have not yet been revised and there is no specific treatment to significantly improve the course of the disease. We report a 69-year-old male who presented to the Lok Nayak Hospital, New Delhi, India, in 2017 with dyspnoea and chest pain. A peripheral blood smear showed an absolute plasma cell count of 2.16 × 10⁹/L. A bone marrow examination showed 61% atypical plasma cells exhibiting kappa light chain restriction. Biochemical investigations were consistent with a diagnosis of primary PCL with renal involvement. Bortezomib-based chemotherapy was initiated, which resulted in an improvement in the patient's haematological and biochemical parameters. This case report includes a comprehensive review of the clinical and diagnostic features, pathobiology and treatment of PCL.

Plasma cell leukemia in North India: retrospective analysis of a distinct clinicohematological entity from a tertiary care center and review of literature

Background

Plasma cell leukemia (PCL) is a rare and aggressive plasma cell neoplasm. In PCL, clonal plasma cells comprise ≥20% of the peripheral blood (PB) leukocytes and/or the absolute clonal PB plasma cell count is ≥2×10⁹/L. Primary PCL (PPCL) originates de novo, whereas, secondary PCL (SPCL) evolves from pre-existing multiple myeloma.

Methods

Clinicohematological features, immunophenotypic profile, and survival of PCL patients were analyzed retrospectively.

Results

Between January 2007 and December 2014, ten PPCL and four SPCL patients were investigated (8 PPCLs and 3 SPCLs had complete clinical data). All were North Indians, sharing common geography and ethnicity. Our cohort showed less frequent renal failure, more frequent hepatomegaly, and non-secretory type disease. In contrast to western literature, flow cytometric immunophenotyping of our cohort revealed altered expression of CD138 (67%), CD56 (33%), and CD20 (0%). With novel therapeutic agents, these PPCL patients had a median overall survival of 15 months.

Conclusion

We highlight that our PPCL patients from North India had distinct clinicohematological and immunophenotypic profiles. The significance of our findings must be tested in a larger patient cohort and must be supported by molecular and cytogenetic investigations to unmask possible significant effects on pathogenesis.