Basal cell carcinoma recurred aggressively after photodynamic therapy

Basal cell carcinomas displayed a histological aggressiveness in recurrences after photodynamic therapy, according to study results.

Researchers studied 12 patients (mean age at recurrence, 66.5 years; six men) with 16 post-photodynamic therapy (PDT) recurrent basal cell carcinomas (BCCs) located on the nose (n=4), frontal area (n=7), temple (n=4) and cheek (n=1). Initial PDTs had been performed twice, separated by at least 1 week, and combined topical application of a photosensitizer, such as methyl aminolevulinate, followed by standardized exposure to visible light. Proportion of histologically aggressive subtypes in BCC recurrences was compared with primary tumors.

Ten patients underwent Mohs’ micrographic surgery, one had conventional surgery, and one was treated with radiotherapy. Biopsies revealed eight superficial and eight modular patterns. Recurrent BCCs indicated a transition from nonaggressive to aggressive subtype in 10 (62.5%) cases. Complete tumor analysis compared with pretherapeutic biopsy specimens in 12 BCCs showed that histological aggressiveness was missed by biopsy alone in 50% of cases.

Possible study biases included more severe BCC recurrences being referred to the hospital that conducted the research, a higher than average proportion of superficial facial BCCs and the accuracy of initial biopsy examinations, the researchers said.

“Our work raises the concern that BCCs recurring after PDT show a more aggressive behavior, resulting in more complex surgical interventions,” the researchers concluded. “Since aggressive BCCs mostly occur on the face, where surgery of recurrences is delicate, we recommend more caution in using PDT for BCCs in this location. Our preliminary findings indicate the need of large-scale follow-up studies to assess the exact frequency and types of relapses of BCC occurring after PDT.”

Published by:

Sources/Disclosures

Collapse

Source:

Fiechter S. Dermatology. 2012;224:346-351.