Accuracy and confidence in the clinical diagnosis of basal cell cancer using dermoscopy and reflex confocal microscopy.

BACKGROUND: Diagnosis of suspected basal cell carcinoma (BCC) is typically confirmed with incisional biopsy before referral to final surgery. OBJECTIVE: To investigate the clinical confidence and accuracy of physicians making a diagnosis of BCC based on dermoscopic and reflectance confocal microscopy (RCM) features. METHODS: This study was designed as a simulation to determine the certainty and willingness to refer to surgery without previous biopsy confirmation of BCC. Study subjects were identified with suspected BCC. Dermoscopic and RCM lesion images were obtained before biopsy. Eight clinicians with various expertise levels blindly interpreted these images and chose among four hypothetical treatment options: definite BCC, refer directly to surgery without biopsy; other malignancy, perform biopsy for diagnosis; uncertain diagnosis, perform biopsy; benign, do not biopsy. Decisions for treatment were based on dermoscopic images alone and, subsequently, on dermoscopic and RCM images combined. RESULTS: The sensitivity for referral to surgery without biopsy was 67.6% with the use of dermoscopy; the positive predictive value (PPV) was 97.0%. Adding RCM increased the sensitivity to 76.5% and the PPV to 98.6%. CONCLUSIONS: Dermoscopy provides a high PPV for BCC. The addition of RCM to dermoscopy increases diagnostic sensitivity, particularly in less experienced dermoscopists. Physician behavior might be different if actual referrals were made for surgery without biopsy.

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.