While tumor recurrence and mortality rates are easy things to measure, cosmetic outcomes are relatively subjective and receive less attention in the literature. For large malignancies arising on cosmetically or functionally sensitive skin, margin control surgery (MCS) offers the dual benefit of a complete excision and the sparing of normal tissue. MCS minimizes the chance of an incomplete excision and maximizes the chance of a good cosmetic outcome.
A 33-year-old man presented with what was thought to be a 2.5-cm benign cyst on the scalp. It had been present for several years and the patient thought it had slowly been growing. His family doctor aimed to completely excise the “cyst” by performing a small elliptical excision.
Histopathology showed a spindle cell tumor consistent with dermatofibrosarcoma protuberans (DFSP) (Figs. 18.1 and 18.2). Immunohistochemistry (IHC) with CD34 (Fig. 18.3) and molecular studies confirmed this diagnosis.
Histopathology showed a spindle cell tumor composed of slender tumor cells embedded uniformly in the collagen stroma without significant mitotic activity. In some areas, there was a high cellularity and irregular, short, intersecting bands of tumor cells forming a storiform and cartwheel pattern.
The tumor invaded subcutaneous fat.
IHC with CD34 was positive, as is seen in almost all cases of DFSP. Melanoma markers (S100, Sox10, not shown) were negative. The diagnosis was confirmed with molecular studies.
The patient was referred for a specialist evaluation and he sought multiple specialist opinions.
An MRI revealed that the lesion measured approximately 4 cm in maximum dimension and that it approached—but did not invade—bone. CT-PET scan revealed no evidence of metastasis.
At one tertiary surgical oncology center, he was offered a wide local excision (WLE) with 2-cm clinical margins. This plan would have involved direct reconstruction and routine (likely bread loaf) pathologic examination of the margins. Postoperative radiotherapy was also recommended, with permanent alopecia over a large area of the scalp being an expected consequence.
The patient was referred to our service and discussed at the multidisciplinary meeting (MDM) which included members from head and neck surgery, radiology, pathology, and oncology, as well as nursing staff. After discussion, the recommendation was for MCS using frozen section examination of the entire margin intraoperatively. This recommendation is in line with the current National Comprehensive Cancer Network® (NCCN) guidelines which recommend MCS for all cases of DFSP where possible.
MCS was performed using the en face 3D technique outlined in Chap. 6. The first level was more like a large mapping biopsy as the extent of the tumor was difficult to discern clinically. Not surprisingly, there was extensive involvement ...