On occasion, the AAD guidelines also make accommodations for an incisional biopsy “of the clinically or dermatoscopically most atypical portion of the lesion.” In this situation, a smaller incisional punch biopsy may be performed of the highly suspicious area.
“There are certainly areas that the investigators have identified which could represent potential knowledge gaps,” Dr. Tsao said. “For instance, 14% of the respondents used a 0.6 cm to 1.0 cm (6 mm-10 mm) margin for melanoma greater than 1 mm.”
Dermatologists’ surveillance of patients in the survey was somewhat less divergent. The most recommended follow-up interval for patients diagnosed within the last 5 years, was 6 months (49%), followed by a 3-month interval (25%), and other (24%). Follow-up was extended to yearly by 63% of dermatologists for patients diagnosed more than five years earlier, Dr. Farberg and Dr. Rigel reported.
Both the AAD and NCCN recommend follow-up every 3 to 12 months for those diagnosed with melanoma within the previous 5 years, while for those diagnosed more than 5 years prior, the AAD recommends follow-up every 3 to 12 months and the NCCN every 12 months.
“Adherence to evidence-based guidelines should lead to improved patient outcomes and quality of care. However, newer studies and emerging data may also justify deviations from existing guidelines, suggesting review of those guidelines may be indicated,” Dr. Farberg and Dr. Rigel concluded.
For example, a prospective series examining surgical margins in 1,072 patients with 1,120 malignant melanoma in situs showed that only 86% were successfully excised with a 6-mm margin, significantly less than the 98.9% clearance achieved with a 9-mm margin, Dr. Farberg told this publication.
That said, a 9-mm margin may not be appropriate for all lesions, such as those on the face, he observed.
The investigators said they hope the survey results will spur on revision of the guidelines, last updated in 2011.
Limitations of the survey include a lack of information on clinical factors such as patient history or anatomic site, the survey may have led to generalized answers, and access to care and reimbursement also may have impacted management, the authors noted.
The response rate to the survey was also low at 8%, with 6,177 practicing U.S. dermatologists surveyed. The demographics of the respondents, however, strongly reflected the full AAD membership, Dr. Farberg said. No significant geographical differences were observed.