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Robert Johr

Publications and source records attributed to Robert Johr.

5 recordsLinked to original sources
PubMed2006

Dermoscopy features of melanoma incognito: indications for biopsy.

BACKGROUND: To avoid missing melanoma, the current practice is to biopsy all suggestive skin lesions. Although most cases of melanoma exhibit clinical clues leading to the correct diagnosis, melanoma can mimic benign lesions. Dermoscopy has been shown to increase the diagnostic accuracy of clinically equivocal lesions, but little is known about its ability to detect melanoma in the context of lesions that appear clinically benign. METHODS: We present 7 difficult-to-diagnose melanomas, in which additional clues provided by dermoscopy increased the index of suggestion and led us to perform a biopsy. RESULTS: Our cases highlight the following 7 management rules: 1) Dermoscopy should not be used only for suggestive skin lesions. 2) Biopsy lesions missing clinicodermoscopic correlation. 3) Biopsy lesions with unspecific pigment pattern. 4) Biopsy lesions with spitzoid features. 5) Biopsy lesions with extensive regression features. 6) In patients with multiple nevi, biopsy lesions changing after short-term follow-up. 7) Biopsy pink lesions with an atypical vascular pattern. LIMITATIONS: The reported series of cases is small. Dermoscopy has not been rigorously compared with handheld magnification (as with a x7 loupe). CONCLUSIONS: Dermoscopy can increase the index of suggestion to perform biopsy in difficult-to-diagnose melanomas.

Adolescent↗
PubMed2005

The performance of SolarScan: an automated dermoscopy image analysis instrument for the diagnosis of primary melanoma.

OBJECTIVE: To describe the diagnostic performance of SolarScan (Polartechnics Ltd, Sydney, Australia), an automated instrument for the diagnosis of primary melanoma. DESIGN: Images from a data set of 2430 lesions (382 were melanomas; median Breslow thickness, 0.36 mm) were divided into a training set and an independent test set at a ratio of approximately 2:1. A diagnostic algorithm (absolute diagnosis of melanoma vs benign lesion and estimated probability of melanoma) was developed and its performance described on the test set. High-quality clinical and dermoscopy images with a detailed patient history for 78 lesions (13 of which were melanomas) from the test set were given to various clinicians to compare their diagnostic accuracy with that of SolarScan. SETTING: Seven specialist referral centers and 2 general practice skin cancer clinics from 3 continents. Comparison between clinician diagnosis and SolarScan diagnosis was by 3 dermoscopy experts, 4 dermatologists, 3 trainee dermatologists, and 3 general practitioners. PATIENTS: Images of the melanocytic lesions were obtained from patients who required either excision or digital monitoring to exclude malignancy. MAIN OUTCOME MEASURES: Sensitivity, specificity, the area under the receiver operator characteristic curve, median probability for the diagnosis of melanoma, a direct comparison of SolarScan with diagnoses performed by humans, and interinstrument and intrainstrument reproducibility. RESULTS: The melanocytic-only diagnostic model was highly reproducible in the test set and gave a sensitivity of 91% (95% confidence interval [CI], 86%-96%) and specificity of 68% (95% CI, 64%-72%) for melanoma. SolarScan had comparable or superior sensitivity and specificity (85% vs 65%) compared with those of experts (90% vs 59%), dermatologists (81% vs 60%), trainees (85% vs 36%; P =.06), and general practitioners (62% vs 63%). The intraclass correlation coefficient of intrainstrument repeatability was 0.86 (95% CI, 0.83-0.88), indicating an excellent repeatability. There was no significant interinstrument variation (P = .80). CONCLUSIONS: SolarScan is a robust diagnostic instrument for pigmented or partially pigmented melanocytic lesions of the skin. Preliminary data suggest that its performance is comparable or superior to that of a range of clinician groups. However, these findings should be confirmed in a formal clinical trial.

Algorithms↗
PubMed2003

Eccrine porocarcinoma arising in a seborrheic keratosis evaluated with dermoscopy and treated with Mohs' technique.

A 78-year-old white woman returned for a routine 6-month skin cancer examination. She had a history of actinic keratosis and multiple basal cell carcinomas. She had no personal or family history of dysplastic nevi or melanoma. The patient was asymptomatic and unaware of any new or changing skin lesions. The patient had multiple lentigines, hemangiomas, and actinic and seborrheic keratoses on all sun-exposed areas. There were no less than 10 seborrheic keratoses on the right mid-back, and one was found to have a 1-cm, reddish nodule asymmetrically located within it (Figs 1 and 2). A clear papule on the left preauricular area was found on biopsy to be a basal cell carcinoma. The nodule on the back was still present 1 month later and it was felt that further evaluation was indicated. As melanoma has been reported to develop in seborrheic keratoses, we decided to examine the lesion using digital dermoscopy. With digital dermoscopy, a well-demarcated reddish nodule was asymmetrically located within a brown lesion. It blanched significantly with pressure. Within the nodule, there were dotted and irregular linear vessels (atypical vascular pattern; also known as polymorphous vascular pattern) and regular-appearing brown dots. Surrounding the reddish nodule, there were pale and pigmented, comedo-like openings, fissures, and ridges (brain-like appearance). Some of the follicular openings appeared to be within the wall of the nodule (Figs 3 and 4). Comedo-like openings, fissures, and ridges are primary dermoscopic criteria for the diagnosis of a seborrheic keratosis; however, the vascular pattern seen has not been reported in seborrheic keratosis. Due to the patient's age and the rarity of significant pathology arising in a seborrheic keratosis, a shave biopsy was performed. To our surprise, the specimen was interpreted by an experienced dermatopathologist as a well-differentiated eccrine porocarcinoma. Due to the high local recurrence rate and metastatic potential of this carcinoma, the patient was referred for Mohs' surgery. Both the basal cell carcinoma and the eccrine porocarcinoma were excised in one stage. A metastatic work-up was negative and the patient appears to be doing well.

Aged↗
PubMed2003

Dermoscopy of pigmented skin lesions: results of a consensus meeting via the Internet.

BACKGROUND: There is a need for better standardization of the dermoscopic terminology in assessing pigmented skin lesions. OBJECTIVE: The virtual Consensus Net Meeting on Dermoscopy was organized to investigate reproducibility and validity of the various features and diagnostic algorithms. METHODS: Dermoscopic images of 108 lesions were evaluated via the Internet by 40 experienced dermoscopists using a 2-step diagnostic procedure. The first-step algorithm distinguished melanocytic versus nonmelanocytic lesions. The second step in the diagnostic procedure used 4 algorithms (pattern analysis, ABCD rule, Menzies method, and 7-point checklist) to distinguish melanoma versus benign melanocytic lesions. kappa Values, log odds ratios, sensitivity, specificity, and positive likelihood ratios were estimated for all diagnostic algorithms and dermoscopic features. RESULTS: Interobserver agreement was fair to good for all diagnostic methods, but it was poor for the majority of dermoscopic criteria. Intraobserver agreement was good to excellent for all algorithms and features considered. Pattern analysis allowed the best diagnostic performance (positive likelihood ratio: 5.1), whereas alternative algorithms revealed comparable sensitivity but less specificity. Interobserver agreement on management decisions made by dermoscopy was fairly good (mean kappa value: 0.53). CONCLUSION: The virtual Consensus Net Meeting on Dermoscopy represents a valid tool for better standardization of the dermoscopic terminology and, moreover, opens up a new territory for diagnosing and managing pigmented skin lesions.

Algorithms↗