Ali Hendi

Melanocytes in nonlesional sun-exposed skin: A multicenter comparative study

BACKGROUND There are limited data regarding melanocyte density and distribution on sun-exposed skin of the head and neck, in particular, comparing morphology (hematoxylin-eosin [H&E] staining) and immunohistochemistry (Melan-A staining) on formalin-fixed tissue. Furthermore, comparisons of melanocyte density between distinct geographic populations have not been made using these methods. This information would be useful for physicians who use histologic criteria to diagnose and treat lentigo maligna. OBJECTIVE We aimed to characterize the density and distribution of melanocytes using Melan-A and H&E stains on nonlesional sun-exposed skin of the face and neck, and compare the results between patients seen in Florida and Minnesota. We also aimed to quantify the presence and extent of features considered characteristic of melanoma in these noncancerous specimens of sun-damaged skin. The overall goal was to be able to provide this information to physicians who perform histopathologic interpretations of skin biopsy specimens to potentially prevent the overdiagnosis of melanoma. METHODS In all, 100 patients undergoing Mohs micrographic and reconstructive surgery for basal cell and squamous cell carcinoma were enrolled, 50 each at the two sites. Permanent tissue sections were prepared from sun-exposed skin without clinical lesions. Melanocyte density and distribution were quantified. RESULTS The overall median and 90th percentile, respectively, of melanocytes per high-power field was 9 and 14 on the H&E-stained sections and 11 and 19 on the Melan-A-stained sections. The means were 9.3 and 12.0, respectively (P < .001). There was evidence that melanocyte densities were higher in patients in Florida than in Minnesota, at least using H&E staining. There was evidence of lower melanocyte densities with increasing age, more so for Melan-A than H&E staining, and higher densities in men using Melan-A. Confluence was noted in 24% of cases using H&E and 45% using Melan-A. More than two thirds of these were classified as having mild confluence, whereas the others demonstrated higher amounts of confluence (3-8 melanocytes). Only 37 patients had a follicle present; of these, 7 patients had follicular extension although this did not extend beyond 1 mm in depth. Cytologic atypia was noted in 19 of the 100 patients; pagetoid spread was found in 3. LIMITATIONS This was a selected population of patients; results may not be generalizable to the wider population. Variables such as contours of the epidermis (rete density), density of hair follicles, and epidermal thickness may affect the reproducibility of the results. Melanomas were not included for comparison. CONCLUSION Relatively high melanocyte density, mild to moderate confluence of melanocytes, focal pagetosis, superficial follicular extension (<1.0 mm), and mild or moderate cytologic atypia may be observed in the absence of a melanocytic neoplasm. It is important for physicians to be aware of these findings so that such features are interpreted appropriately when making a histologic assessment that may ultimately influence therapy and outcome.

Unifocality of extramammary Paget disease.

Extramammary Paget disease is a rare tumor that often is associated with multiple recurrences after wide local excision. Over the years, the theory that this tumor is multicentric has been accepted without detailed scrutiny. We describe a patient with unifocal extramammary Paget disease. Axillary extramammary Paget disease was treated with Mohs micrographic surgery and intraoperative cytokeratin 7 immunostaining. With the use of the information from scouting biopsies and the Mohs map, a two-dimensional recreation of the tumor showed two contiguous, thin, long, finger-like projections extending from the main body of the tumor. Extramammary Paget disease may be a contiguous tumor with a highly irregular pattern of spread on the skin. It can have finger-like projections beyond the main body of the tumor. These subclinical projections may not be observed with routine hematoxylin-eosin staining. Cytokeratin 7 immunostaining is required to visualize Paget cells that extend beyond the main body of the tumor.

Dermatofibrosarcoma Protuberans of the Vulva Treated Using Mohs Micrographic Surgery

First described by Darier and Ferrand in 1924,1 dermatofibrosarcoma protuberans (DFSP) is a rare, low-grade sarcoma with a tendency for recurrence. The overall annual incidence is 4.2 per million, or 0.1% of all cancers.2 It tends to affect young to middle-aged adults and occurs more often in blacks

Subcutaneous Trigger Point Causing Radiating Postsurgical Pain

BACKGROUND The immediate onset of severe postoperative pain, especially pain radiating distant from the incision site, is uncommon after dermatologic surgery. OBSERVATION A 37-year-old woman undergoing excision of a nevus from the left side of her midback had an exquisitely tender spot along the incision lines. This tender spot was hard to anesthetize and was clinically visible, after excision of the nevus, as a fibrous bundle in the subcutaneous plane. She presented in the immediate postoperative period with referred (distant) pain extending down the ipsilateral arm that was caused by a thoracic subcutaneous trigger point. CONCLUSION Surgeons and pain management specialists should be aware of this potential cause of immediate postoperative pain to prevent unnecessary medical or surgical interventions in the postoperative period.

Tissue Conserving Technique for Reconstruction of Nasal Lining Defects.

Reconstruction of large, full-thickness through-andthrough defects of the nose can present a surgical challenge (Figure 1). Preventing significant patient morbidity, while maintaining favorable cosmetic and functional outcome, must also be considered. There are various options for reconstructing the nasal lining, including the turnover skin flap, a septal hinge flap, a full-thickness skin graft (FTSG), or secondary intention healing. The turnover skin and septal hinge flap are preferred in defects limited to one cosmetic subunit. Although technically straightforward to perform, a FTSG creates a second surgical site with added morbidity and a possibility of graft failure. Graft failure is particularly a concern in smokers, patients with diabetes, or obese patients. Wentzell describes a case of a full-thickness nasal defect repaired with a dorsal nasal flap with secondary intention healing of the mucosal lining. Split-thickness skin grafts (STSG) from a second site have been used to repair the nasal mucosal lining with success. The alternative presented is the utilization of a STSG from skin thatwill ultimately be discarded, specifically from the pedicle or Burow’s triangle of the paramedian forehead flap (PFF).

Complications of Skin Cancer Treatment

Treatment of skin cancers has an inherent risk of complications, as with any other medical treatment. The main complications seen with the surgical treatment of skin cancers are the same as with any other surgery. They include infection, bleeding, dehiscence, and necrosis. These four interrelated complications are often referred to as the “terrible tetrad” (Hendi 2007). The rate of these complications is relatively low with dermatologic surgery procedures (Cook and Perone 2003; Aasi and Leffell 2003).

Nonmelanoma Skin Cancer

Skin cancers are broadly divided into melanoma and nonmelanoma skin cancers (NMSC). Due to the relatively low risk of metastasis from squamous cell carcinoma (SCC) and the extremely low risk of metastasis from basal cell carcinoma (BCC), these, the two most common cutaneous malignancies, are, for the most part, considered jointly as NMSC. This term is a bit of a misnomer; there are many other cutaneous malignancies that are not melanoma, but because of their more aggressive clinical behavior, they tend not to be grouped under this moniker.

Miscellaneous Cutaneous Neoplasms

Because of their low incidence and aggressive malignant potential, rare tumors such as atypical fibroxanthoma (AFX), dermatofibrosarcoma protuberans (DFSP), Merkel cell carcinoma, and sebaceous carcinoma are not discussed in greater detail in this atlas. For the sake of familiarization with the appearance of some of these benign and malignant neoplasms, the following images are included (Figs. 5.1–5.17).