PALM BEACH, FLA. - Shave biopsy of possible melanomas usually provides enough diagnostic information to plan a successful surgical treatment, judging by a retrospective study of 600 patients.
The procedure has been controversial, because many surgeons believe it fails to give a full clinical picture of the lesion – especially thickness, said Dr. Stephen Grobmyer of the University of Florida, Gainesville. However, in his review of 600 patients who had shave biopsies at two surgical centers in 2006-2009, just 22% of patients had residual melanoma after the procedure, with tumor upstaging required in 2% and a wider margin excision in 1%.
"We feel the definitive treatment planning for melanoma can be reliably made on results of shave biopsy. We advocate the liberal use of shave biopsy for suspicious cutaneous lesions; this should be emphasized over other techniques of biopsy, as this would advance the early diagnosis of melanoma and improve outcomes," Dr. Grobmyer said at the annual meeting of the Southern Surgical Association.
Dermatologists and family physicians can easily perform the shave biopsy, which Dr. Grobmyer said is "easy, quick, cheap, safe, and doesn't require suture closure or postoperative follow-up."
All patients in the study had undergone shave biopsies of lesions less than 2 mm in depth. This was considered the cut-off point because patients with deeper lesions usually go on to have a wide excision and sentinel node biopsy, Dr. Grobmyer said.
The patients' median age was 62 years, and 40% were female. "It's interesting to note that dermatologists performed about 90% of the shave biopsies on patients who were referred, and that on clinical exam, more than two-thirds did not have a diagnosis of melanoma. Most had a diagnosis of nonmelanoma skin cancer or a benign skin lesion."
Based on the results of the shave biopsy, however, 88% of the lesions were confirmed as melanoma. Of these, 11% were invasive, with a median Breslow depth of 0.73 mm. Ulceration was present in 6% of patients, and 37% had a positive deep margin on the shave biopsy.
All who had the shave biopsy went to initial surgical management based on the depth of the shave. "After the sentinel node biopsy, only 3% of patients needed additional surgery," Dr. Grobmyer pointed out.
The researchers especially wanted to analyze the subset of patients who had a diagnosis of melanoma made on clinical observation before the biopsy was done – a total of 179 patients (30%). "On shave, we found that 22% had a positive deep margin, which is statistically significantly less than those patients who did not have a preshave diagnosis of melanoma, suggesting that the shaves were done in a way as to more completely excise the lesion."
Evaluation of these patients after initial surgical management revealed that there were very few instances of tumor upstaging (3%), need for wider excision (3%), or a change in the need for sentinel node biopsy (1%).
Dr. Grobmyer acknowledged that the study's 12-month follow-up period was fairly short. "We saw a 2.3% overall recurrence rate with 1.7% local regional and 0.7% distant recurrences. It’s also important to note that the patients with recurrence had much deeper lesions than those who did not, with an average depth of 1.7 mm."
"It may be time to stop bashing shave biopsies," Dr. Kelly McMasters said during the discussion period. "The conventional dogma among melanoma experts against shave biopsy has been that they're bad because they underestimate true tumor thickness," said Dr. McMasters of the University of Louisville (Ky.) "This suggests that shave biopsies fall below the standard of care, but nearly every melanoma patient I've seen has had a shave biopsy for diagnosis. Are all these physicians practicing below the standard of care? It seems [that] because shave biopsies are what’s being performed most commonly, they are the standard of care."
The most important point of the study, however, is that the easily accessible shave biopsy, in the hands of primary care physicians, can get melanoma patients into surgical treatment faster – and time is life in this case, said Dr. Hiram C. Polk Jr.
"The only improvement in survival in melanoma has been due to earlier diagnosis, and you don't want to do anything to discourage the dermatologists or the family physicians from doing a biopsy," said Dr. Polk, the Ben A. Reid Sr. Professor of Surgery at the University of Louisville. "The worst thing they can do is say 'come back in 3 months,' or cauterize them. This paper encourages people with lesser surgical skills to get any piece of the lesion, as long as they won't be doing the diagnosis. The shave biopsy is a good thing, and we need to share this and encourage those in dermatology and family medicine to do more of them."