The optimal therapy and radiation dose for patients with localized primary cutaneous B-cell lymphoma (PCBCL) are unknown. We retrospectively identified 23 patients with localized (T1-T2) PCBCL treated with definitive radiation to doses ranging from 30 to 44 Gy (median, 36 Gy). With a median follow-up of 4.8 years, the 5-year overall survival rate was 100%, the relapse-free survival rate was 71% (95% confidence interval, 46-86%) and there were no local recurrences, suggesting that radiotherapy to a dose of 30 Gy may be sufficient for cure.