Periocular Presentation of Solitary Plasmacytomas and Multiple Myeloma

Aims: To describe patients with periocular solitary extramedullary plasmacytoma (SEMP) and multiple mycloma (MM), together with an estimate of the risk of progression from SEMP to MM. Patients and methods: A retrospective case-note review for patients seen between 1978 and 2020, examining demographics, presentation, imaging, pathology, management, and outcome. Results:Twenty patients (10 male; 50%) presented at a mean age of 60.9 years, with an average symptom duration of 4.5 months. Ten (50%) patients had known systemic myeloma at ophthalmic presentation (the MM group) and, on average, they presented one decade earlier than those with occult MM discovered after orbital biopsy (p=0.06); the majority (9/15; 60%) of patients with MM were female, whereas there was a male bias (4/5; 80%) with SEMP (p= 0.30). Most tumors (15/20; 75%) were within the anterior part of the orbit, especially superolaterally (16 patients; 80%), and the soft-tissue mass often appeared to explode from the frontal bone or greater wing o f the sphenoid (16/20; 80%). Full treatment details were known for 19 patients: 6 (32%) had solely orbital radiotherapy, 4 (21%) chemotherapy, 6 (32%) combined chemoradiation, and 3 (16%) had combined chemoradiation with stem-cell transplant (Table 3). After an average follow up of 58 months, 1/5 (20%) patients with SEMP and 11/15 (73%) with MM had tumor-related death. The overall survival probability for all 20 patients with periocular plasmacytoma was 34% at 5 and 10 years, with MM patients having a worse outlook (27% 5-year, and 18% 10-year survival) compared with SEMP (53% survival at 5 and 10 years) (p = 0.18). None of the 5 patients with SEMP progressed to systemic MM over an average follow up of 9.1 years. Conclusions: Although 50% patients with periocular plasmacytoma appear to have a SEMP at ophthalmic presentation, a half of these patients were found to have occult MM within 6 months of biopsy. Of those without systemic disease around the time of biopsy, none developed MM over an average follow up of more than 9 years.

Automated summary

This study describes the characteristics of patients with periocular solitary extramedullary plasmacytoma (SEMP) and multiple myeloma (MM) and estimates the risk of progression from SEMP to MM. The results show that although half of the patients initially presented with SEMP, half of them were found to have occult MM within 6 months of biopsy.