Diffuse dermal angiomatosis of the thigh as the presenting sign of critical limb ischemia.

Diffuse dermal angiomatosis (DDA) is a rare, benign disease that can serve as the precursor to critical limb ischemia. Pruritic, erythematous plaques form from a proliferation of endothelial cells in response to dermal hypoxia. We present the case of a 63-year-old female patient with DDA of the left medial thigh, followed by ischemia of her distal extremities. Revascularization of her left leg resulted in resolution of the DDA and healing of her ulcers. DDA can be an important clue to identify significant peripheral vascular disease.

Clinical Follow-up of Atypical Spitzoid Tumors Analyzed by Fluorescence In Situ Hybridization.

Many neoplasms with spitzoid features remain enigmatic, especially those with intermediate grade features or "atypical spitzoid tumors" (ASTs). Fluorescence in situ hybridization (FISH) has emerged as a complementary technique to conventional microscopy, with certain chromosomal patterns conveying diagnostic information. In this study, we examined 36 ASTs analyzed by FISH for specific abnormalities in chromosomes 6, 9, and 11. Aberrations were detected in 11 cases, 7 of which met FISH criteria for spitzoid melanoma. These had homozygous deletion of 9p21, partial deletion of 11q13, gain of 6p25, and gain of 11q13. All 3 patients with positive sentinel lymph nodes, including one with progression beyond the sentinel lymph node, had homozygous deletion of chromosome 9p21, but there were no deaths in an average of 28 months of follow-up of these cases. Other aberrations in the chromosomal pattern of ASTs were heterozygous deletion of 9p21, partial deletion of 6p23, and tetraploidy. We found that ASTs, including those eventually diagnosed as spitzoid melanoma, had a more indolent course in our cohort than conventional malignant melanoma. Moreover, the addition of FISH results led to a more definitive diagnosis in 7 cases, 4 of which had abnormalities on FISH consistent with spitzoid melanoma.

Histopathologic evaluation of the sentinel lymph node for malignant melanoma: the unstandardized process.

Metastasis from malignant melanoma (MM) usually first presents in the draining lymph node basin and thus sentinel lymph node (SLN) biopsy is a staging tool used to predict risk of metastases and death in higher risk tumors and has become the standard of care. Differences in the processing and methods used in the histopathological examination of SLNs can affect the positivity rate for metastatic MM because isolated MM deposits may be small and variably distributed in the SLN. The examination of SLNs is not standardized. The authors surveyed institutions across the United States who process SLNs for MM to better characterize the current methods used and to suggest a standardized approach to improve the reliability of the SLN biopsy. A survey of 142 academic institutions in the United States regarding the methods used in the evaluation of the SLN biopsy for MM was conducted. Thirty-two institutions responded. Eighty-one percent of the institutions (26 of 32) had a protocol that they used for SLN examination. In regards to gross dissection, 28% of the responders (9 of 32) initially bivalve (cut the SLN in half), whereas 59% (19 of 32) use a bread loaf technique, cutting the SLN at even intervals without specifically commenting about orientation to the hilum. The number of levels initially cut from the SLN block varied from 1 to 8 levels per block. Thirty-nine percent of the respondents (12 of 31) routinely order immunohistochemistry before evaluation of the initial hematoxylin- and eosin-stained sections. Eighty percent of the respondents (24 of 30) report the maximum dimension of the metastatic tumor deposit. The response rate was low (22%), and most respondents did not indicate how many SLN accessions were performed at their institution each year. Histologic protocols for processing SLNs for MM vary among institutions. Different methods of handling SLNs result in varying sensitivities for detection of metastases. Data derived from these varied approaches to develop and determine prognostic and staging categories may be inconsistent. A standardized yet practical approach is needed to provide reliable information on which prognosis can be determined and therapeutic guidelines can be based. The hope is for dermatologists and those treating patients with MM to understand the intricacies and inconsistencies involved in performance and interpretation of this key staging tool.