A case of malignant pleural mesothelioma and relapsed mantle cell lymphoma under concomitant treatment with a good response and tolerance

Full text: Case presentation: A 73-year-old male physician with multiple clinical comorbidities. He was diagnosed with a mantle cell lymphoma (MCL) stage IVA in 2014 treated with 8 cycles of R-CHOP and consolidation with high-dose chemotherapy followed by autologous hematopoietic stem cell transplant with complete remission. In 2016 had a nodal relapse treated with rituximab, bortezomib and dexamethasone. In Nov 2020 a melanoma pT1a was resected. In Dec 2020 presented with dyspnea with chest CT scan showing a 65 x 55 mm pleural mass and small pleural effusion, and patient noted multiple subcutaneous nodules. Pleural tumor was diagnosed as mixed mesothelioma (epithelioid and sarcomatoid) and subcutaneous nodule as MCL. PET-CT showed multiple areas of pleural masses and thickenings (the biggest 83 x 38 mm SUV 28.5), small pleural effusion and multiple subcutaneous nodules (the biggest frontal at right 22 x 8 mm SUV 5.5) as well as axillary, retropectoral, bilateral inguinal and left external iliac hypermetabolic lymph nodes. Started on nivolumab + ipilimumab on Mar 26 with respiratory clinical improvement. CT scans from Jul 2021 showed partial response. Because of progression of subcutaneous nodules, started on ibrutinib since Jul 3 with nodules reduction after 2 weeks of use. Despite concurrent immunotherapy (IO) combination and tyrosine kinase inhibitor (TKI), patient has a good tolerance to treatment, with only diarrhea G1 and seborrheic dermatitis G2. Discussion: Malignant pleural mesothelioma (MPM) is a rare malignancy mostly related to occupational asbestos exposure. Prognosis is poor, with median overall survival (OS) of around 1 year and 5-year OS of 10%. Standard 1st line treatment for inoperable or metastatic MPM is IO based on CheckMate 743 phase 3 trial. Nivolumab + ipilimumab increased OS vs platinum-based chemo (median OS 18·1 vs 14·1 months; HR 0·74; p=0·0020), with benefit regardless of histology and acceptable toxicity profile. 2-year OS was 41% (IO) vs 27% (chemo). MCL is a subcategory of B cell non-Hodgkin lymphomas (NHL), usually aggressive and with variable course. Incidence is 3-10% in NHL adults in Western countries and has an unfavorable median OS of 8 to 10 years with treatment. Final comments: We presented an unusual case of a patient with synchronous malignancies, MPM and MCL, under concomitant treatment with IO combination and TKI, with good tolerability and response to treatment. (author)