P-333: Synchronic Occurrence of Multiple Myeloma, POEMS Syndrome and Prostate Adenocarcinoma - is there role for autologous stem cell transplant?

Introduction: The concomitant occurrence of multiple myeloma (MM) and prostate adenocarcinoma (PA) has been described, as well as the concomitant occurrence of POEMS syndrome and MM. However, our literature review did not verify previous reports of patients with the simultaneous diagnosis of the three entities, making the diagnostic and therapeutic approach of this case challenging .



A 57y male, hypertensive, diabetic and dyslipidemic, also with motor sequelae due to a previous Guillain Barret, had been diagnosed with indolent PA (Gleason 7, normal PSA) in routine exams, following a watch and wait approach. Staging CT’s which detected sclerotic lesions in the vertebrae and ischium. Hepatosplenomegaly and chronic portal vein thrombosis were also found, with a negative investigation for thrombophilia. A non-quantifiable IgA/lambda monoclonal peak was found. The patient did not have anemia, kidney damage or hypercalcemia. A bone marrow biopsy was performed finding 60% of clonal plasma cells (culminating in a diagnosis of MM with therapeutic indication) and a biopsy of one of the sclerotic lesions in the ischium has ruled out a metastatic prostate lesion. Karyotype 46,XY. FISH unavailable. ISS 2 and R-ISS scored at least 2. He arrived with high ACTH and normal cortisol values, and presented polyneuropathy. VEGF=5,055.4pg/mL. Thus, our patient also met criteria for POEMS. No skin changes or papilledema were detected. The patient refused CSF collection.



Despite a high-risk HCT-CI score, the team figured he was a fairly fit patient for autologous stem cell transplant (ASCT). We opted for the DARA-VTD protocol. After the 4th cycle the patient was taken to ASCT (Mobilization GCSF 10mcg/kg per 5 days; 7.6 x10a6 cells collected, conditioning MEL 140, infusion: 2/3/24; engraftment: D+14). Currently, the patient is on D+131 of the transplant, with complete response (CR) to the MM treatment. VEGF on 3/13/24 was measured at 775.3 pg/mL, also indicating a reduction in inflammatory activity related to POEMS. Although there were no major changes in PET-SCAN in both prostate and sclerotic lesions uptake, the patient evolved with an increase in PSA levels (currently at 7) and was referred for radiotherapy for the treatment of the PA. He is currently in the 2nd cycle of maintenance treatment for MM with lenalidomide (now 5mg due to neutropenia and thrombocytopenia).

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Conclusions: Synchronous occurrence of MM, POEMS and PA is uncommon in the literature. Our one-case experience was not able to detect a negative impact of the presence of indolent prostate adenocarcinoma at any stage of myeloma treatment, nor in ASCT. It is uncertain whether the treatment instituted for myeloma contributed to the enhancement of the PSA and whether it eventually contributed to the anticipation of therapeutic indication for prostate cancer. More studies are needed with patients with synchronous tumors to better evaluate such impacts. The patient remains under clinical follow-up and is in good general condition.