Treatment Outcomes of Low-grade Lymphoma of the Orbit

C L Holloway; T Pickles; N S Croteau; E S Wai

doi:10.1016/j.clon.2022.01.042

Treatment Outcomes of Low-grade Lymphoma of the Orbit

Clin Oncol (R Coll Radiol). 2022 Jul;34(7):e298-e304. doi: 10.1016/j.clon.2022.01.042. Epub 2022 Feb 21.

Authors

C L Holloway¹, T Pickles², N S Croteau³, E S Wai⁴

Affiliations

¹ Radiation Oncology, University of British Columbia, BC Cancer, Victoria, British Columbia, Canada. Electronic address: cholloway@bccancer.bc.ca.
² Radiation Oncology, University of British Columbia, BC Cancer, Vancouver, British Columbia, Canada.
³ Department of Mathematics and Statistics, University of Victoria, Victoria, British Columbia, Canada.
⁴ Radiation Oncology, University of British Columbia, BC Cancer, Victoria, British Columbia, Canada.

PMID: 35210133
DOI: 10.1016/j.clon.2022.01.042

Abstract

Aims: Radiation therapy can be used with curative intent in patients with low-grade orbital non-Hodgkin's lymphoma (NHL) stages IE and IVE (limited to the bilateral orbits). This study evaluated local control and survival outcomes of patients with unilateral or bilateral orbital lymphoma treated in a provincial population.

Materials and methods: The study subjects were 176 patients with low-grade orbital or conjunctival lymphoma referred for management from 1980 to 2016. Demographic, tumour and treatment characteristics were abstracted by chart review. Recurrence-free survival (RFS) and overall survival were assessed with competing risks analysis and Gray's test.

Results: The median follow-up was 8.5 years (range 0.4-29.5 years). The median age at diagnosis was 65 years (range 20-97 years). The most common histological subtype was mucosa-associated lymphoid tissue (MALT) (73%). Stage IVE accounted for 20.5% of the cohort. Orbital radiation therapy was used in 122 patients with stage IE (87%) and 12 patients with stage IVE (28%). The median dose was 25 Gy (range 2-35 Gy). Other treatments were antibiotics (seven patients), chemotherapy (10 patients), radioimmunotherapy (six patients), surgery (three patients) and observation (16 patients). Within the group treated with orbital external beam radiation therapy (EBRT) there were no local recurrences. Among those with stage IE NHL, EBRT was associated with improved local RFS (P ≤ 0.001) but did not have an impact on contralateral or distant RFS. In patients with stage IVE NHL limited to the bilateral orbit, bilateral EBRT was associated with improved RFS (P = 0.012) but did not affect distant recurrences or overall survival.

Conclusion: There were no local recurrences after EBRT for stage IE and IVE orbital low-grade NHL. The treatments offered over the study period varied, but only EBRT for stage IVE disease improved RFS. This supports EBRT as the preferred primary treatment for patients with localised orbital low-grade lymphoma, including those with bilateral disease.

Keywords: Bilateral orbital involvement; low-grade orbital lymphoma; radiation therapy and radioimmunotherapy.

MeSH terms

Adult
Aged
Aged, 80 and over
Humans
Lymphoma
Lymphoma, Non-Hodgkin* / drug therapy
Lymphoma, Non-Hodgkin* / radiotherapy
Middle Aged
Orbit / pathology
Orbital Neoplasms* / radiotherapy
Recurrence
Retrospective Studies
Treatment Outcome
Young Adult

Supplementary concepts

Orbital lymphoma