Topical Sildenafil in the Treatment of Hand-Foot Syndrome and Hand-Foot Skin Reaction: A Retrospective Study.

e22095 Background: Hand-foot syndrome (HFS) and hand-foot skin reaction (HFSR) are painful, debilitating, and often dose-limiting complications of anticancer agents. These cutaneous reactions are encountered with chemotherapy and VEGF multikinase inhibitors (MKIs). There is no standard effective treatment for HFS/HFSR. Methods: We conducted a retrospective study to describe the efficacy of sildenafil 2% cream (S2C) in treatment of established HFS/HFSR. Patients treated with S2C for HFS/HFSR from Apr 2013 to Oct 2015 were identified in pharmacy records. Chart review was performed to collect clinical data such as patient characteristics, agent associated with HFS/HFSR, treatment response and duration. Primary outcome was clinical improvement of HFS/HFSR. Clinical improvement was graded as: none (no), mild (mild), moderate (mod), and marked (mark), defined as 0, < 1, 1, > 1 grade improvement, respectively in NCI CTCAE. Maximum overall improvement in pain or skin was summarized descriptively. Results: Fifty-three patients received S2C for HFS/HFSR. Two of 53 patients received S2C on 2 separate HFS/HFSR occasions with different regimens. We therefore had a total of 55 records over a 33 month period. There were 23 (42%) records of HFS/HFSR due to VEGF MKI, 19 (35%) from cape plus bevacizumab (bev)/ziv-aflibercept (ziv), and 13 (33%) from cape alone or plus other agent. Patients received S2C twice a day after onset of HFS/HFSR. Overall, 78% (43/55) had at least mild improvement of HFS/HFSR after S2C (25% mark, 15% mod, 38% mild, 16% no, 6% not evaluable). Of those receiving VEGF MKI, 57% (13/23) had mark/mod improvement (35% mark, 22% mod, 22% mild, 9% no, 13% not evaluable). Of those receiving cape plus bev/ziv, 26% (5/19) had mark/mod improvement (21% mark, 5% mod, 53% mild, 21% no). Of those receiving cape alone or plus other agent, 31% (4/13) had mark/mod improvement (15.5% mark, 15.5% mod, 46% mild, 23% no). No toxicity from S2C was reported. Conclusions: Sildenafil cream is a promising HFS/HFSR treatment. This study recorded a 78% rate of clinically meaningful improvement to established HFS/HFSR after S2C. Further studies are warranted to investigate the efficacy of topical sildenafil in treatment of HFS/HFSR.