How Dermatologic Surgeons Decide to Proceed with Surgery for Nonmelanoma Skin Cancer When Site Identification is Initially Uncertain: A Nationwide, Multicenter, Prospective Study.

Background: Few studies show how dermatologic surgeons manage problems with site identification.

Objective: To estimate frequency and characterize management of skin cancer treated by surgery when the anatomic location of the tumor is in question.

Methods: Nationwide, prospective, multi-site cohort study.

Results: Among 17,076 cases at 22 centers, 98 (0.60%) were lesions in question (LIQ) for which site identification was initially uncertain, with these more often in patients who were male, older, and biopsied more than 30 days ago. Surgeons employed on average 5.0 (95% CI: 4.61-5.39) additional techniques to confirm the site location, with common approaches including: re-checking available documentation (90 lesions, 92%); performing an expanded physical examination (89 lesions, 91%); and asking the patient to point using a mirror (61 lesions, 62%). In 15%, photographs were requested from the biopsying provider, and also in 15%, frozen section biopsies were obtained. In 10%, the referring physician was contacted. Eventually, surgeons succeeded in definitively identifying 82% (80/98) of initially uncertain sites, with the remaining 18% (18/98) postponed. Most postponed surgeries were at non-facial sites.

Limitations: Sites were academic centers.

Conclusions: When the anatomic location of the tumor is uncertain, dermatologic surgeons use multiple methods to identify the site, and sometimes cases are postponed.