Primary non-Hodgkin’s lymphoma (NHL) of the orbit is rare. Orbital NHLs show good response to both radiotherapy (RT) and chemotherapy, and hence, the emphasis should be to ensure maximum cure rate with minimum morbidity. In this study, we present the clinical profile and treatment outcomes of patients with NHL who had initial presentation in the orbit.

In this retrospective analysis, case records of patients with a diagnosis of NHL of the orbit were analysed from January 2005 to January 2015. Patients were worked up and staged according to the Ann Arbor system. Patients with large tumours were initially given chemotherapy with CHOP regimen (cyclophosphamide, vincristine, adriamycin and prednisolone) three weekly for 4–6 cycles. Patients with residual disease were given RT 20–30 Gy at 2 Gy per fraction. RT when given as a primary treatment consisted of 36–45 Gy at 1·8–2 Gy per fraction on either Cobalt 60 machine or linear accelerator.

A total of 52 patients with diagnosis of orbital NHL were included in this study. Median age at presentation was 57 years (range 13–71). Left, right and bilateral orbit was involved in 21 (40%), 28(54%) and 3(6%) patients, respectively. Low- and high-grade pathology was seen in 39(75%) and 13(25%) patients, respectively. On immunohistochemistry, 23(44%) tumors were CD 20 positive. After staging, 33 (63%) patients had stage I disease. Median tumour size was 4·0 × 3·2 × 1·5 cm (1·7 × 1·7 × 1·4 cm to 5·8 × 4·0 × 4·7 cm). Primary RT was given to 7(13%) patients. Upfront chemotherapy was given in 45(86·5%) patients, out of which 24 had stage I disease. RT consolidation was done in 26 (50%) patients for residual disease after chemotherapy. Median follow-up was 88 months (range 29–183 months). Relapse occurred in 6(9·6%) patients; 2 local; 2 local + distant and in 2 distant alone. These patients were successfully salvaged with systemic chemotherapy and local RT. One patient died due to neutropenia. Overall survival in this series was 96%.

Excellent local control was achieved with initial chemotherapy followed by RT for primary orbital NHL with minimal toxicity. We recommend a dose of 36–40 Gy for definitive RT and 30 Gy for lymphoma following chemotherapy using 2 Gy/fraction for Indian patients who present with bulky tumours. RT should be incorporated in treatment of orbital NHL whenever possible as it is safe, effective and is associated with minimal complications.