Reliability of diagnosis from Mohs slides: interpersonal and intrapersonal agreement on basal cell carcinoma presence and histological subtype.

BACKGROUND: The success of Mohs micrographic surgery (MMS) depends partly on the correct diagnosis of slides. OBJECTIVES: To determine reliability of diagnosis from Mohs slides. METHODS: This was a prospective study evaluating the reliability of diagnosis from Mohs slides of basal cell carcinoma (BCC) presence, BCC location on the slide and BCC subtype among six raters who independently assessed 50 Mohs slides twice with a 2-month interval. Slides were randomly selected whereby difficult-to-diagnose slides were oversampled. For each slide, a reference diagnosis was established by an expert panel. Cohen's kappa (κ) was calculated to determine levels of agreement interpersonally (rater vs. reference diagnosis) and intrapersonally (rater at T1 vs. T2). Multivariable logistic regression was used to determine independent risk factors for slides with interpersonal discordant diagnosis. The variables studied were BCC presence, whether a slide was scored as easy or difficult to diagnose, review duration of the 50 slides, profession and years of experience in diagnosis from Mohs slides. RESULTS: Interpersonal and intrapersonal agreement were substantial on BCC presence (κ = 0·66 and 0·68) and moderate on BCC subtype (κ = 0·45 and 0·55). Slides that were scored as difficult to diagnose were an independent risk factor for interpersonal discordant diagnosis on BCC presence (odds ratio 3·54, 95% confidence interval 1·81-6·84). CONCLUSIONS: Reliability of diagnosis from Mohs slides was substantial on BCC presence and moderate on BCC subtype. For slides that are scored difficult to diagnose, a second opinion is recommended to prevent misinterpretation and thereby recurrence of skin cancer.

Recurrence rate of lentigo maligna after micrographically controlled staged surgical excision.

BACKGROUND: Lentigo maligna is a slowly growing melanoma in situ. Current guidelines advise wide local excision with a margin of 5 mm as the treatment of first choice, which has recurrence rates ranging from 6% to 20%. OBJECTIVES: To determine retrospectively the recurrence rate of lentigo maligna after staged surgical excision. METHODS: Records of all patients with lentigo maligna treated with our method of staged surgical excision between 2002 and 2011 were retrieved. To identify recurrences we used the computer program Sympathy, which is linked to PALGA, a nationwide network and registry of histo- and cytopathology in the Netherlands. RESULTS: We identified 100 patients, who were treated with staged surgical excision with 100% immunohistopathological control of lateral margins. Digital pictures were used to facilitate orientation during the several stages of surgery. After a mean follow-up of 60 months, four patients had a recurrence, after 37, 58, 74 and 77 months of follow-up. CONCLUSIONS: Staged surgical excision is superior in clearance and recurrence rates to wide local excision for lentigo maligna and should be considered as the treatment of first choice in national and international guidelines.

Additional review of Mohs slides to optimize Mohs micrographic surgery.

BACKGROUND: One significant risk factor for recurrence after Mohs surgery is misinterpretation of slides. OBJECTIVES: To determine how often pathologists detected incompletely excised basal cell carcinoma (BCC) on Mohs slides and to determine risk factors for incompletely excised BCCs. METHODS: This retrospective study included 1653 BCCs treated with Mohs surgery in a university hospital between 2007 and 2011. For routine quality assurance, all slides were additionally reviewed by a pathologist within 1 week of the procedure. For this study, all cases that had divergent interpretations were re-evaluated by a Mohs surgeon and a pathologist. Mixed-effects logistic regression models with Mohs surgeon effects as random effects were used to determine risk factors for incompletely excised BCC. RESULTS: Incompletely excised BCCs were detected in 31 cases (2%), in which defects > 20 mm in diameter were an independent risk factor (odds ratio 3.58, 95% confidence interval 1.55-8.28). Other studied variables (i.e. aggressive subtype, previously treated BCC, location on nose and > 2 Mohs stages) did not affect the risk of incompletely excised BCCs. CONCLUSIONS: The additional review of Mohs slides might increase accurate interpretation, especially in large BCCs.

Mohs micrographic surgery for basal cell carcinomas: appropriateness of 'Rotterdam' criteria and predictive factors for three or more stages.

BACKGROUND: In the Netherlands basal cell carcinomas (BCC) are eligible for Mohs microscopic surgery (MMS) if certain criteria are fulfilled. OBJECTIVE: To study the MMS indication criteria practised at the department of dermatology of the Erasmus University Medical Center, Rotterdam and to identify predictive factors for extensive subclinical tumour spread among BCCs eligible for MMS. METHODS: Pre-operative patient and tumour characteristics were derived retrospectively between January 2nd 2006 and December 28th 2009 from 1174 patient records, accounting for 1464 BCCs. Multivariate logistic regression models were used to calculate crude and adjusted odds ratios (OR) with 95% confidence intervals (CI) for one vs. two or more stages and for narrow (≤ 2 stages) vs. extensive subclinical spread (≥ 3 stages). RESULTS: H-zone location [adjusted OR 1.51 (95% CI 1.16-1.96)], recurrent tumour [adjusted OR 1.50 (95% CI 1.11-2.02)], aggressive subtype [adjusted OR 1.25 (95% CI 1.01-1.56)] and tumour size ≥ 11 mm [adjusted OR 1.53 (95% CI 1.20-1.96)] were significantly associated with two or more stages. Predictive factors for extensive subclinical spread were recurrent tumour [adjusted OR 2.26 (95% CI 1.61-3.17)], tumour size ≥ 21 mm [adjusted OR 1.69 (95% CI 1.13-2.51)] and location in the H-zone [adjusted OR 1.68 (95% CI 1.15-2.46)]. CONCLUSION: 'Rotterdam' indication criteria used for MMS are appropriate. Predictors for extensive subclinical spread are important for patients' and surgeons' expectations prior to the operation about time span, defect size, reconstruction and possible associated morbidity.

Evidence-based decisions for local and systemic wound care.

BACKGROUND: Decisions on local and systemic wound treatment vary among surgeons and are frequently based on expert opinion. The aim of this meta-review was to compile best available evidence from systematic reviews in order to formulate conclusions to support evidence-based decisions in clinical practice. METHODS: All Cochrane systematic reviews (CSRs), published by the Cochrane Wounds and Peripheral Vascular Diseases Groups, and that investigated therapeutic and preventive interventions, were searched in the Cochrane Database up to June 2011. Two investigators independently categorized each intervention into five levels of evidence of effect, based on size and homogeneity, and the effect size of the outcomes. RESULTS: After screening 149 CSRs, 44 relevant reviews were included. These contained 109 evidence-based conclusions: 30 on venous ulcers, 30 on acute wounds, 15 on pressure ulcers, 14 on diabetic ulcers, 12 on arterial ulcers and eight on miscellaneous chronic wounds. Strong conclusions could be drawn regarding the effectiveness of: therapeutic ultrasonography, mattresses, cleansing methods, closure of surgical wounds, honey, antibiotic prophylaxis, compression, lidocaine-prilocaine cream, skin grafting, antiseptics, pentoxifylline, debridement, hyperbaric oxygen therapy, granulocyte colony-stimulating factors, prostanoids and spinal cord stimulation. CONCLUSION: For some wound care interventions, robust evidence exists upon which clinical decisions should be based.

Neoplasms of the facial skin.

Neoplasms of the skin are found most often on the face. Malignant tumors of the facial skin pose a challenge in treatment, prohibiting compromises between oncologically responsible surgery and functional plus cosmetic outcome. The incidence of melanoma and nonmelanoma skin cancers is rising. Not all malignancies of the skin need to be treated by surgery. For in situ variants there are other options, such as photodynamic therapy and medical treatment. Knowledge of the clinical manifestation, behavior, and prognosis and histopathologic analysis lead to correct diagnosis and choice of suitable treatment. This article presents a synopsis of nonmelanoma, melanoma, and other cancers of the skin.

Hyperpigmentation during interferon-alpha therapy for chronic hepatitis C virus infection.

Many types of skin disorders concomitantly occur with hepatitis C virus infection. These skin lesions may be induced or worsened during antiviral therapy with interferon-alpha (IFN). To our knowledge, hyperpigmentation of the skin--and especially of the tongue--has not been reported so far. We describe two dark-skinned patients who developed hyperpigmented skin and tongue lesions during combination therapy with IFN and ribavirin. Immunohistochemical analysis of tongue biopsies confirmed the suspicion of melanin deposits in these areas of hyperpigmentation. We hypothesize that during interferon therapy, melanocytes may produce more melanin pigment in the presence of alpha-melanocyte stimulating hormone and sufficient amounts of tyrosine, leading to melanin deposits and clinical hyperpigmentation.

Diagnostic tests in children with atopic dermatitis and food allergy.

BACKGROUND: Skin testing is a common diagnostic procedure in food allergy. The skin prick test is the test of first choice for investigating the immediate IgE-mediated reaction. The skin application food test (SAFT) has been developed on the basis of the mechanism of the contact urticaria syndrome (CUS). METHODS: We studied the relevance of the SAFT in children younger than 4 years with atopic dermatitis and (suspected) food allergy as compared with the prick-prick test, the radioallergosorbent test (RAST), and the oral challenge. In the skin tests, we used fresh food, in the same state as it was consumed. RESULTS: There was a good agreement between the SAFT and the prick-prick test. A moderate agreement was observed between the SAFT and the serologic test (RAST). Significantly more positive results in the RAST were observed than in the SAFT. There was very good agreement between the SAFT and the oral challenge (kappa = 0.86). CONCLUSIONS: The SAFT is a reliable and child-friendly skin test for evaluating (suspected) food allergy in children younger than 4 years with atopic dermatitis. The very good correlation with the oral challenge indicates that one may probably consider the SAFT a "skin provocation" in children younger than 4 years.