Francesca Farnetani

Is confocal microscopy a valuable tool in diagnosing nodular lesions? A study of 140 cases

Nodular lesions pose diagnostic challenges because nodular melanoma may simulate all kinds of melanocytic and nonmelanocytic lesions. Reflectance confocal microscopy (RCM) is a novel technique that allows visualization of the skin at nearly histological resolution although limited laser depth penetration hampers visualization of the deep dermis.

In vivo confocal microscopy for detection and grading of dysplastic nevi: A pilot study

BACKGROUND Dysplastic nevi are thought to be precursors of melanoma during a stepwise process. However, this concept is still controversial and precise correlation between clinical and histopathologic features is lacking. In vivo confocal microscopy represents a noninvasive imaging technique producing horizontal sections at nearly histopathologic resolution. OBJECTIVE We sought to determine whether specific histologic features in dysplastic nevi have reliable correlates on confocal microscopy and to develop an in vivo microscopic grading system. METHODS Sixty melanocytic lesions with equivocal dermatoscopic aspects, corresponding to 19 nondysplastic nevi, 27 dysplastic nevi, and 14 melanomas, were analyzed by confocal microscopy and histopathology, using the Duke grading criteria. RESULTS All architectural and cytologic features of the Duke grading score had significant reflectance confocal microscopy correlates. Confocally, dysplastic nevi were characterized by a ringed pattern, in association with a meshwork pattern in a large proportion of cases, along with atypical junctional cells in the center of the lesion, and irregular junctional nests with short interconnections. A simplified algorithm was developed to distinguish dysplastic nevi from melanoma and nondysplastic nevi. The contemporary presence of cytologic atypia and of atypical junctional nests (irregular, with short interconnections, and/or with nonhomogeneous cellularity) was suggestive of histologic dysplasia, whereas a widespread pagetoid infiltration, widespread cytologic atypia at the junction, and nonedged papillae suggested melanoma diagnosis. LIMITATIONS A small number of cases were evaluated because of the necessity to analyze numerous histopathologic and confocal features. CONCLUSION The possibility to detect dysplastic nevi in vivo may lead to an appropriate management decision.

Skin Cancer Diagnosis With Reflectance Confocal Microscopy: Reproducibility of Feature Recognition and Accuracy of Diagnosis

IMPORTANCE Reflectance confocal microscopy (RCM) studies have been performed to identify criteria for diagnosis of skin neoplasms. However, RCM-based diagnosis is operator dependent. Hence, reproducibility of RCM criteria needs to be tested. OBJECTIVE To test interobserver reproducibility of recognition of previously published RCM descriptors and accuracy of RCM-based skin cancer diagnosis. DESIGN, SETTING, AND PARTICIPANTS Observational retrospective web-based study of a set of RCM images collected at a tertiary academic medical center. Nine dermatologists (6 of whom had ≥3 years of RCM experience) from 6 countries evaluated an RCM study set from 100 biopsy-proven lesions, including 55 melanocytic nevi, 20 melanomas, 15 basal cell carcinomas, 7 solar lentigines or seborrheic keratoses, and 3 actinic keratoses. Between June 15, 2010, and October 21, 2010, participanting dermatologists, blinded to histopathological diagnosis, evaluated 3 RCM mosaic images per lesion for the presence of predefined RCM descriptors. MAIN OUTCOMES AND MEASURES The main outcome was identification of RCM descriptors with fair to good interrater agreement (κ statistic, ≥0.3) and independent correlation with malignant vs benign diagnosis on discriminant analysis. Additional measures included sensitivity and specificity for diagnosis of malignant vs benign for each evaluator, for majority diagnosis (rendered by ≥5 of 9 evaluators), and for experienced vs recent RCM users. RESULTS Eight RCM descriptors showed fair to good reproducibility and were independently associated with a specific diagnosis. Of these, the presence of pagetoid cells, atypical cells at the dermal-epidermal junction, and irregular epidermal architecture were associated with melanoma. Aspecific junctional pattern, basaloid cords, and ulceration were associated with basal cell carcinomas. Ringed junctional pattern and dermal nests were associated with nevi. The mean sensitivity for the group of evaluators was 88.9% (range, 82.9%-100%), and the mean specificity was 79.3% (range, 69.2%-90.8%). Majority diagnosis showed sensitivity of 100% and specificity of 80.0%. Sensitivity was higher for experienced vs recent RCM users (91.0% vs. 84.8%), but specificity was similar (80.0% vs. 77.9%). CONCLUSIONS AND RELEVANCE The study highlights key RCM diagnostic criteria for melanoma and basal cell carcinoma that are reproducibly recognized among RCM users. Diagnostic accuracy increases with experience. The higher accuracy of majority diagnosis suggests that there is intrinsically more diagnostic information in RCM images than is currently used by individual evaluators.

Integration of reflectance confocal microscopy in sequential dermoscopy follow-up improves melanoma detection accuracy

Successful treatment of melanoma depends on early diagnosis, but its varied clinical presentation means that no single noninvasive method or criterion can provide reliable detection in all cases.

Towards an in vivo morphologic classification of melanocytic nevi

Nevi are common benign neoplasms and the main diagnostic entity in the differential diagnosis of melanoma. Reflectance confocal microscopy (RCM), a novel technique for skin imaging at cellular‐level magnification, has been shown to be useful for differentiating nevi from melanoma. However, systematic studies of the specific RCM features of nevi are still lacking.

Dermoscopic difficult lesions: an objective evaluation of reflectance confocal microscopy impact for accurate diagnosis

Early detection of melanoma is the main objective to ensure a high survival rate. In some cases melanoma diagnosis still remain difficult and this leads to unnecessary excisions.

Reflectance confocal microscopy correlates of dermoscopic patterns of facial lesions help to discriminate lentigo maligna from pigmented nonmelanocytic macules

The clinical recognition of lentigo maligna (LM) and LM melanoma can be very challenging due to the overlapping features it shares with other pigmented macules of the skin. Noninvasive diagnostic techniques can assist in the differential diagnosis.

Cost–benefit of reflectance confocal microscopy in the diagnostic performance of melanoma

The sub‐optimal diagnostic accuracy for melanoma leads to excise a high number of benign lesions, with consequent costs. Reflectance confocal microscopy (RCM) improves diagnostic specificity, thus possibly inducing a reduction in unnecessary excisions and related costs.

Spitz naevi and melanomas with similar dermoscopic patterns: can confocal microscopy differentiate?

Differentiating Spitz naevi from melanomas can be difficult both clinically and dermoscopically. Previous studies have reported the potential role of in vivo reflectance confocal microscopy (RCM) in increasing diagnostic accuracy.

CDKN2A and MC1R variants influence dermoscopic and confocal features of benign melanocytic lesions in multiple melanoma patients

Non‐invasive diagnostic tools are effective in the histomorphological study of melanocytic lesions. The role of melanoma susceptibility genes on melanocytic nevi histopathological features is not clear. The current study aimed to correlate genetic alterations and histomorphological features of melanocytic nevi. Clinical, dermoscopic and confocal features of 34 multiple melanoma patients and 34 controls were compared. Among patients with melanoma, carriers of CDKN2A mutations and/or MC1R variants, and wild‐type genes were also compared. In patients with melanoma, a lighter phototype (P = 0.051), a higher number of nevi (P < 0.01) and clinically atypical nevi (P < 0.01) were observed. At dermoscopy, these nevi showed a complex pattern (P = 0.011), atypical network (P = 0.018) and irregular pigmentation (P = 0.037); at confocal, an irregular meshwork pattern (P = 0.026) with atypical nests (P = 0.016) and an inflammatory infiltrate (P = 0.048) were observed. Among patients with melanoma genetically tested, CDKN2A G101W mutation carriers were more frequently younger (P = 0.023), with clinically atypical nevi (P = 0.050), with cytological atypia (P = 0.033) at confocal. G101W mutation and MC1R variants carriers showed hypopigmented nevi (P = 0.002) and, at confocal, roundish cells infiltrating the junction (P = 0.019). These data suggest an influence of CDKN2A mutation and MC1R variants in the development of dysplastic melanocytic lesions. Non‐invasive histomorphological evaluation, together with genetic studies, improves melanoma risk identification and early diagnosis, for a patient‐tailored management.