# Does Double Mean Trouble? Coexistence of Myeloproliferative and Lymphoproliferative Neoplasms

## TL;DR

This study explores rare cases where patients have both myeloproliferative and lymphoproliferative neoplasms, finding that these patients tend to have more aggressive disease and higher risks.

## Contribution

The study provides new insights into the clinical characteristics and risks of coexisting myeloproliferative and lymphoproliferative neoplasms.

## Key findings

- Patients with MPN followed by LPN had more aggressive lymphoproliferative neoplasms and higher mortality.
- Polycythemia vera and chronic lymphocytic leukemia were most commonly associated in coexistence cases.
- Most patients had molecular-cytogenetic abnormalities, suggesting genetic instability and increased neoplasm risk.

## Abstract

Background: The occurrence of myeloproliferative neoplasms (MPNs) that evolve into each other is well-described, as is this occurrence of lymphoproliferative neoplasms (LPNs). However, less is known about rare MPN/LPN coexistence, and the aim of our study was to analyze charachteristics of these patients after long term follow-up. Methods: Fourteen patients with MPN/LPN coexistence were diagnosed and treated according to guidelines at a single university center across two decades. Results: The overall median age was 53 years (22–69). MPNs patients with subsequent LPNs had a shorter period of second malignancy development and a more aggressive course of LPN, which can cause fatal outcomes. Polycythemia vera and chronic lymphocytic leukemia were most commonly associated (36%). The JAK2V617F mutation had 2/3 and cytogenetic abnormalities occurred in 1/3 of patients. MPN/LPN coexistence cases had significantly higher thrombotic potential (42.8%) and a higher third malignancy accruement frequency (21.4%) versus those without such malignancies. Conclusions: Considering the younger ages at MPN diagnosis, it is recommended to check regularly for blood lymphocytosis or lymphadenopathy occurrences and organomegaly progression faster than expected for MPN, with the aim of timely LPN diagnoses. The presence of molecular-cytogenetic abnormalities in a majority of patients indicate possible genetic instability and increased risk of development of multiple neoplasms, thus elevating thrombotic risk.