Serum tissue polypeptide antigen correlating with clinical course in a patient with mycosis fungoides: a potential disease marker?

human papillomavirus and molluscum contagiosum. The primary action of cidofovir is the selective inhibition of viral DNA polymerase, blocking viral DNA synthesis and replication. Subsequent studies showed cidofovir directs antineoplastic activity towards DNA virus-related cancers. International literature reports many examples of HPV-related oesophageal and respiratory papillomatous tumours, nasopharyngeal carcinomas, cervical intraepithelial neoplasia and erythroplasia of Queyrat. Some reports confirmed the usefulness of topical 1% cidofovir for the treatment of non-DNA virus-related cutaneous cancers, such as basal and squamous cell carcinomas. Finally, there are two reports of cidofovir efficacy for the treatment of melanoma. The first was published by Redondo et al., who achieved melanoma regression in guinea pigs after systemic administration of cidofovir; the second was by my group, regarding the regression of a dermal metastasis from melanoma after intralesional cidofovir. The mechanism of cidofovir as an antineoplastic agent is still unknown. The involution observed in the neoplastic tissue after topical or intralesional administration of cidofovir is thought to be related to a decrease in DNA thymidine incorporation, induction of apoptosis through activation of tumour suppressor genes p53, pRb and p21, and inhibition of neoangiogenesis from cidofovir. Of course we cannot assess the complete healing of LM in our patients with the evidence of histological healing from two punch biopsies. However, the patients were kept under strict observation, and the absence of recurrences after a 48-month follow-up period may be indicative of healing. No systemic side-effects related to the treatment were noted. The final cosmetic results were excellent. We emphasize that surgical excision is the treatment of choice for in situ melanoma. However, this experience shows the potential effectiveness of 1% cidofovir in the nonsurgical treatment of LM. Appropriate clinical trials and prolonged follow-up periods are needed to confirm this very preliminary observation.