Complete response to talimogene laherparepvec in a primary acral lentiginous melanoma

Talimogene laherparepvec (T-VEC) is an oncolytic virus, approved for the treatment of stage IIIb-IVM1a melanoma with injectable disease (cutaneous, subcutaneous or lymphatic). It is a modified herpes simplex virus type 1 that induces tumor-specific T-cell responses via reduction of virally mediated suppression of antigen presentation, stimulation of viral pathogenicity and enhancement of tumor-selective replication. Response rates up to 82.6% have been reported for stage III disease. Acral lentiginous melanoma (ALM) is a rare subtype of melanoma with a poor prognosis. Here, we present a case of an elderly and frail patient with primary ALM who refused surgical treatment and consented to receive T-VEC as first-line drug therapy. After 10 courses of treatment, a histopathologically confirmed complete response was achieved. To our knowledge, this is the first case ever reported in which a primary ALM is (successfully) treated with T-VEC.