The effectiveness of radiotherapy for leukemia cutis.

BACKGROUND: Leukemia cutis (LC) is a rare clinical presentation of leukemia that is associated with poor prognosisabs. To date, the value of radiotherapy (RT) for the treatment of LC remains controversial. Therefore, the aim of this study was to analyse the effectiveness of various RT doses for LC. METHODS AND MATERIALS: Between January 2000 and January 2016, 13 patients underwent RT at our institution after exhibiting progressive disease following other treatment modalities.
RESULTS: A total of 36 radiation courses were administered to 13 patients (8 females, 5 males) with a median age of 41 years (range 2-76). Radiation modalities included 32 focal treatments, while total skin electron beam therapy was applied to four patients. The median RT dose was 27 Gy (range 8-34). A complete response rate (CRR) to RT was achieved for 32/36 (89%) lesions (100% for AML lesions versus 33% for the other leukemias; P < 0.001). The median duration of local control (DOLC) for the entire cohort was 38 months (range 0-98), while the median survival (MS) from the time of LC presentation was 13 months (range 2.5-106). The CRR for the LC lesions treated with high-dose regimens (>26 Gy) versus low-dose regimens (≤26 Gy) was 95 versus 83%, respectively (P = 0.26), and the median DOLC was 44 months versus 10 months, respectively (P = 0.019). AML patients had a better long-term outcome than the other patients according to median DOLC (40 months versus 2 months, respectively; P < 0.001) and MS (24 versus 6 months, P = 0.004). RT was well tolerated without significant adverse events.
CONCLUSION: A radiation dose ≤26 Gy confer a comparable CRR to high-dose regimens and appears to be an effective treatment for controlling LC progression. However, radiation doses >26 Gy were associated with a longer DOLC. LC patients with underlying AML are associated with better outcome compared with other types of leukemia.