Pattern of care and impact of prognostic factors on the outcome of head and neck extramedullary plasmacytoma: a systematic review and individual patient data analysis of 315 cases

Head and neck extramedullary plasmacytoma is a rare localized plasma cell neoplasm. We intended to perform this review of the published literature to assess the demographic profile, pattern of care and survival outcomes. Two authors independently searched PubMed, Google search and Cochrane library for eligible studies from 1950 till July 1, 2016, published in English language. Median age of the cohort was 57 years (range 11-85). Site-wise distributions were paranasal sinuses 22.3% (70), nasal cavity 17.5% (55), nasopharynx 10.8% (34). Median size of SEMP was 3 cm (range 0.3-12 cm). Treatment distribution was radiotherapy (RT) in 52% (164), surgery (S) 19% (60), chemotherapy (C) 5% (16), S + RT 23.49% (74),CRT 1.9% (6), S + C 0.6% (2), S + RT + C 0.95% (3).Radiation was used as a modality in 78.4%(247), surgery in 44.1%(139), chemotherapy in 4.8%(15). Median radiation dose used was 45 Gy with range 20-61 Gy. Median overall survival (OS) was 40 months (range 0.5-298). Median local progression-free survival was 36 months (range 0-298). Median myeloma relapse-free survival was 36 months (range 0.5-298). Five- and 10-year OS was 78.33 and 68.61%. Five-year cause-specific survival (CSS) and 10-year CSS was 90.15 and 83.31%. Five-year LPFS was 94.78%, and 10-year LPFS was 88.43%. Five-year myeloma progression-free survival was 84.46%, and 10-year myeloma PFS was 80.44%. The factors associated with risk of local relapse were site of disease (sinonasal), secretory EMP, type of treatment received (surgery + RT > RT alone > surgery on univariate analysis). Risk factors for myeloma relapse were coexisting diseases, site of disease (sinonasal), bony erosion, size of lesion > 5 cm and type of treatment received on univariate analysis. Our study shows that combined modality S + RT is superior compared to uni-modality in preventing local recurrence. Radiation dose of 45 Gy is optimal. Nodal irradiation has no impact on local recurrence.