Addressing Skin Tension With Biopsies

   I would like to applaud Tracey Vlahovic, DPM, for her article entitled “A Guide to Biopsy Techniques for Skin Neoplasms” (see page 50–56 in the May issue of Podiatry Today). Any information that turns attention to the skin biopsy in podiatric literature is sorely needed.

   I would like to comment on her statement on page 52 that “The elliptical incision should be parallel to the relaxed skin tension lines for the best scar” when discussing excisional and incisional biopsy techniques. While the statement is technically correct regarding the eventual scar, if one is dealing with a suspected malignancy, such as a highly suspicious pigmented lesion, the long axis of the ellipse must be parallel to the direction of the lymphatic drainage. In the case of the leg and foot, this is never medial to lateral but distal to proximal.

   One should not consider the relaxed skin tension lines. Should a wide local excision of the biopsy site be required, a surgical scar oriented medial to lateral will require a much wider re-excision (which one should also perform parallel to the direction of the lymphatic drainage) than if one were to perform the biopsy according to protocol. For the biopsy of pigmented lesions in the nail matrix, medial to lateral or transverse elliptical incisions are preferred.

   Of course, Dr. Vlahovic’s advice regarding the best scar results is entirely appropriate for dermatitis and other lesions not considered suspicious for malignancy at the time of biopsy.
— Bryan C. Markinson, DPM
Chief, Podiatric Medicine and Surgery
The Leni and Peter W. May
Dept. of Orthopedic Surgery
Mt. Sinai School of Medicine, New York City

   Dr. Vlahovic responds: I appreciate Dr. Markinson’s comments but I stand by my statement to consider skin tension lines in cases where it is reasonable. This article addressed the generality of the skin biopsy and not necessarily the biopsy of the suspicious lesion only. This statement of following relaxed skin tension lines is reiterated in the literature multiple times (Lawrence’s An Introduction to Dermatological Surgery, Bolognia’s Dermatology, etc.).

   The podiatric surgeon will be the best at ultimately determining where and how to place the incision on a case to case basis. However, this article was solely meant to introduce basic techniques of the skin biopsy or for review for those who have not used the technique in a while.

— Tracey C. Vlahovic, DPM, FAPWCA
Associate Professor
Temple University School of Podiatric Medicine