Distinct Clinico-Pathological Profile of Plasma Cell Leukemia Patients from North India

Introduction: Plasma cell leukemia (PCL) is a rare and aggressive plasma cell neoplasm where clonal plasma cells comprise ≥ 20% of peripheral blood (PB) leukocytes and/or absolute clonal PB plasma cell count is ≥ 2×10⁹/L. Primary plasma cell leukemia (PPCL) originates de novo, whereas, secondary plasma cell leukemia (SPCL) evolves from pre-existing multiple myeloma (MM). Literature does reveal a few large case series on PCL, however, data on this rare neoplasm is very sparse from Indian sub-continent. We present clinico-pathological profile 14 cases of PCL from single tertiary care centre of north-India.

Materials and methods: Archival files were screened for period of 8 years (Jan 2007 to Dec 2014) and clinico-pathological profile, including overall survival, of patients of PCL was systematically analysed, retrospectively.

Results: Ten PPCL and four SPCL patients were traced in duration of 8 years, all belonging to north-Indian states of Punjab and Haryana. Eight PPCL and three SPCL patients had complete clinical data. Our patients had less frequent renal failure (12.5%), more frequent hepatomegaly (75%) and non-secretory type (33%) disease. Flow cytometric immunophenotyping revealed expression of CD138 (67%), CD56 (33%) and CD20 (0%), which was different from reported western data. With novel therapeutic agents, these patients fared a higher median survival of 15 months.

Conclusion: Our patients of PCL from neighbouring states of north-India have a distinct clinico-pathological profile, with better survival as compared to existing literature. The significance of our findings must be tested in a larger patient cohort and must be supported with molecular and cytogenetic investigations to unmask any significant pathogenesis.