Pathologic Evaluation of Skin Tumors With Ex Vivo Dermoscopy With Derm Dotting.

IMPORTANCE: Ex vivo dermoscopy (EVD) with derm dotting (DD) improves clinicopathologic correlation and the quality of diagnosis in skin tumors. OBJECTIVE: To compare the diagnostic performance of the standard method of skin biopsy processing with the practice of EVD with DD. DESIGN, SETTING, AND PARTICIPANTS: This retrospective study compares the diagnostic performance in 6526 skin biopsy specimens examined from 2008 to 2010 with a standard method of processing with 8584 biopsy specimens examined in 2015 with EVD and DD. Data were analyzed from January 1 to March 31, 2016. A total of 15 110 skin biopsy specimens were included. The biopsy specimens from 2008 to 2010 were processed in a hospital-based general pathology laboratory; the biopsy specimens from 2015 were processed in a private dermatopathology laboratory. Biopsy specimens from both periods were diagnosed by the same dermatopathologist. MAIN OUTCOMES AND MEASURES: The primary outcome measures were clinicopathological characteristics, usefulness of EVD with DD, and turnaround times (TATs). RESULTS: Use of EVD with DD increased the detection of positive section margins in nonmelanoma skin cancer from 8.4% to 12.8%. The most significant increase was seen in Bowen disease, invasive squamous cell carcinoma, and a superficial type of basal cell carcinoma (BCC). With EVD and DD, a specific clinicopathologic diagnosis was made in 27.7% of nevi compared with only 10.3% using the standard method. The incidence of moderately and severely dysplastic nevi increased from 1.0% to 7.2% and from 0.6% to 1.4%, respectively. The detection of ulceration in melanomas with thicker than 1 mm increased from 24.0% to 31.3%. The number of nevi-associated melanomas increased from 15.5% to 33.3%. The number of collision lesions from 0.07% to 1.07%. The TAT for nevi decreased from 2 days to 1 day, for melanomas from 5 days to 2 days, and for BCC from 2 days to 1 day. CONCLUSIONS AND RELEVANCE: Ex vivo dermoscopy and DD with adapted sectioning in a dermatopathology setting allows a more accurate and less time consuming histopathologic diagnosis of skin tumors. These findings suggest that pathologists involved in skin tumor evaluation should be encouraged to learn dermoscopy and replace random transverse cutting with lesion-specific and DD-guided cutting.

Comparison of Ex Vivo and In Vivo Dermoscopy in Dermatopathologic Evaluation of Skin Tumors.

IMPORTANCE: Ex vivo dermoscopy (EVD) can be a valuable tool in routine diagnostic dermatopathologic evaluation. OBJECTIVES: To compare in vivo dermoscopy (IVD) and EVD and to provide guidance for routine dermatopathologic evaluations. DESIGN, SETTING, AND PARTICIPANTS: This observational study collected 101 consecutive IVD and EVD images of skin tumors from a private dermatology practice from March 1 to September 30, 2013. Four observers (3 dermatologists and 1 dermatopathologist) blinded to the histopathologic diagnoses independently scored and compared the colors, structures, and vessels of EVD images with those of the corresponding IVD images. Data were analyzed from January 1 to March 31, 2014. MAIN OUTCOMES AND MEASURES: Concordance between the EVD and IVD images and gain or loss of colors, structures, and vessels on EVD relative to IVD images. RESULTS: The final analysis included 404 observations of 101 images. The EVD image was generally similar to the corresponding IVD image but clearly darker, with new areas of blue in 130 of 404 observations (32.2%) and white in 100 of 404 observations (24.8%) and loss of red in 283 of 404 observations (70.0%). Most structures were well preserved. New structureless areas were found in 78 of 404 observations of EVD images (19.3%), and new crystalline structures were detected in 68 of 404 observations of EVD images (16.8%). On EVD images, squames and crusts were lost in 56 of 404 observations (13.9%) and 43 of 404 observations (10.6%), respectively. Blood vessels were lost in 142 of 404 observations of EVD images (35.1%). CONCLUSIONS AND RELEVANCE: The EVD image is an important new tool in dermatopathology and may give direction to targeted tissue processing and examination of skin tumors.

Histopathological cutaneous alterations in systemic sclerosis: a clinicopathological study.

INTRODUCTION: The aims of the present study were to identify histopathological parameters which are linked to local clinical skin disease at two distinct anatomical sites in systemic sclerosis (SSc) patients with skin involvement (limited cutaneous systemic sclerosis (lcSSc) or diffuse cutaneous systemic sclerosis (dcSSc)) and to determine the sensitivity of SSc specific histological alterations, focusing on SSc patients without clinical skin involvement (limited SSc (lSSc)). METHODS: Histopathological alterations were systematically scored in skin biopsies of 53 consecutive SSc patients (dorsal forearm and upper inner arm) and 18 controls (upper inner arm). Clinical skin involvement was evaluated using the modified Rodnan skin score. In patients with lcSSc or dcSSc, associations of histopathological parameters with local clinical skin involvement were determined by generalised estimation equation modelling. RESULTS: The hyalinised collagen score, the myofibroblast score, the mean epidermal thickness, the mononuclear cellular infiltration and the frequency of focal exocytosis differed significantly between biopsies with and without local clinical skin involvement. Except for mononuclear cellular infiltration, all of the continuous parameters correlated with the local clinical skin score at the dorsal forearm. Parakeratosis, myofibroblasts and intima proliferation were present in a minority of the SSc biopsies, but not in controls. No differences were found between lSSc and controls. CONCLUSIONS: Several histopathological parameters are linked to local clinical skin disease. SSc-specific histological alterations have a low diagnostic sensitivity.