Accuracy of tele-consultation on management decisions of lesions suspect for melanoma using reflectance confocal microscopy as a stand-alone diagnostic tool.

BACKGROUND: Diagnostic accuracy of reflectance confocal microscopy (RCM) as a stand-alone diagnostic tool for suspect skin lesions has not been extensively studied. OBJECTIVE: Primary aim was to measure experts' accuracy in RCM-based management decisions. Secondary aim was to identify melanoma-specific RCM features. METHODS: The study enrolled patients ≥18 years that underwent biopsy of skin lesions clinically suspected to be melanoma. One hundred lesions imaged by RCM were randomly selected from 439 lesions prospectively collected at four pigmented lesion clinics. The study data set included 23 melanomas, three basal cell and two squamous cell carcinomas, 11 indeterminate melanocytic lesions and 61 benign lesions including 50 nevi. Three expert RCM evaluators were blinded to clinical or dermoscopic images, and to the final histopathological diagnosis. Evaluators independently issued a binary RCM-based management decision, 'biopsy' vs. 'observation'; these decisions were scored against histopathological diagnosis, with 'biopsy' as the correct management decision for malignant and indeterminate lesions. A subset analysis of 23 melanomas and 50 nevi with unequivocal histopathological diagnosis was performed to identify melanoma-specific RCM features. RESULTS: Sensitivity, specificity and diagnostic accuracy were 74%, 67% and 70% for reader 1, 46%, 84% and 69% for reader 2, and 72%, 46% and 56% for reader 3, respectively. The overall kappa for management decisions was 0.34. Readers had unanimous agreement on management for 50 of the 100 lesions. Non-specific architecture, non-visible papillae, streaming of nuclei, coarse collagen fibres and abnormal vasculature showed a significant association with melanoma in the evaluation of at least two readers. CONCLUSIONS: Reflectance confocal microscopy tele-consultation of especially challenging lesions, based on image review without benefit of clinical or dermoscopy images, may be associated with limited diagnostic accuracy and interobserver agreement. Architectural and stromal criteria may emerge as potentially useful and reproducible criteria for melanoma diagnosis.

White shiny structures: dermoscopic features revealed under polarized light.

BACKGROUND: White shiny structures, including white shiny lines, white shiny areas and rosettes, are features only observed under polarized dermoscopy (PD). OBJECTIVE: To evaluate the prevalence of the varied morphologies of white shiny structures in melanoma, basal cell carcinoma (BCC), squamous cell carcinoma (SCC), actinic keratosis (AK) and lichen planus-like keratosis (LPLK). METHODS: Retrospective study using dermoscopic images of biopsy-proven melanoma, BCC, SCC, AK and LPLK. RESULTS: A total of 538 lesions were assessed under PD. One or more types of white shiny structures were observed in 38.7% of study lesions (208/538). BCCs were significantly more likely to display a combination of white shiny areas and white shiny lines (short lines and/or ill-defined strands) (31.9%; 61/191) than any other lesions (P<0.001). BCC were more likely than other lesions to have white shiny lines distributed without any organized pattern (P<0.001). Lines in melanoma were significantly more likely than other lesion types to be oriented orthogonally (P<0.001). When white shiny lines were present, melanomas were significantly more likely than other lesions to exhibit short discrete white lines (P<0.001). Rosettes were significantly more likely to be observed in actinic tumours than other lesions (P<0.001). CONCLUSION: The presence of white shiny lines of any length accompanied by white shiny areas is most suggestive of a diagnosis of BCC (P<0.001). Melanomas are more likely to display short white shiny lines in an orthogonal distribution (P<0.001) and without white shiny areas. Actinic tumours are most likely to exhibit rosettes (P<0.001).

Reflectance confocal microscopy criteria of lichen planus-like keratosis.

BACKGROUND: Lichen planus-like keratosis (LPLK) may be difficult to differentiate from melanoma and other skin cancers on sun-damaged skin based on clinical and dermoscopic examination. Reflectance confocal microscopy (RCM) allows evaluation of skin lesions at high resolution. OBJECTIVES: The aim of this study was to identify criteria for specific diagnosis of LPLK using in vivo RCM. METHODS: Lesions included in the study were derived from patients presenting for skin examination at a private dermatology practice specializing in skin cancer. We retrospectively analysed RCM features of 28 biopsy-proven LPLK and compared them to RCM findings in skin cancers on sun-damaged skin, including five in situ squamous cell carcinomas, six actinic keratoses, seven superficial basal cell carcinomas and eight melanomas. RESULTS: The main RCM features of LPLK and their relative frequencies were: (i) typical honeycomb pattern of the spinous layer (78.6%); (ii) elongated cords and/or bulbous projections at the dermal-epidermal junction (75%); and (iii) numerous plump-bright cells and/or bright stellate spots in the superficial dermis (92.9%). These RCM features correlated with the following histopathological findings respectively: (i) spinous-granular layers without significant atypia of keratinocytes; (ii) elongated, bulbous rete ridges; and (iii) dense infiltration of melanophages and lymphocytes in superficial dermis. We propose diagnostic criteria that classify correctly 71.4% of LPLK, while avoiding misclassification of any of the skin cancers in the present series as LPLK. CONCLUSIONS: We identified RCM criteria for diagnosis of LPLK that correlate well with histopathological findings and that allow differentiation of LPLK from skin cancer.

Cloudy and starry milia-like cysts: how well do they distinguish seborrheic keratoses from malignant melanomas?

BACKGROUND: Seborrheic keratoses are the most common skin lesions known to contain small white or yellow structures called milia-like cysts (MLCs). Varied appearances can sometimes make it difficult to differentiate benign lesions from malignant lesions such as melanoma, the deadliest form of skin cancer found in humans. OBJECTIVE: The purpose of this study was to determine the statistical occurrence of MLCs in benign vs. malignant lesions. METHODS: A medical student with 10 months experience in examining approximately 1000 dermoscopy images and a dermoscopy-naïve observer analysed contact non-polarized dermoscopy images of 221 malignant melanomas and 175 seborrheic keratoses for presence of MLCs. RESULTS: The observers found two different types of MLCs present: large ones described as cloudy and smaller ones described as starry. Starry MLCs were found to be prevalent in both seborrheic keratoses and melanomas. Cloudy MLCs, however, were found to have 99.1% specificity for seborrheic keratoses among this group of seborrheic keratoses and melanomas. CONCLUSION: Cloudy MLCs can be a useful tool for differentiating between seborrheic keratoses and melanomas.

The significance of multiple blue-grey dots (granularity) for the dermoscopic diagnosis of melanoma.

BACKGROUND: The presence of multiple blue-grey dots (MBGD) is widely used by clinicians to decide if a pigmented lesion should be removed, but only little is known about their significance. OBJECTIVES: To evaluate the significance of MBGD for the dermoscopic diagnosis of melanoma. METHODS: In part 1 we retrospectively evaluated 340 pigmented lesions for the presence and morphological appearance of granularity. One hundred and seventy melanomas were included and matched with 170 benign and dysplastic naevi which were randomly chosen from our collection. In part 2, 3773 lesions were examined prospectively in at-risk patients: all lesions with granularity were recorded, surgically removed and subjected to histopathological examination. RESULTS: In part 1, granularity was found in 26.5% of the benign lesions and 93.5% of melanomas. The presence of granularity, granularity at the periphery, irregularly distributed granularity and granularity in association with red and white colour were statistically highly significant for the diagnosis of melanoma (P < 0.001). In part 2, granularity was found in 1.08% of the 3773 lesions and more frequently in sun-damaged skin. Sensitivity for the diagnosis of melanoma was 85% and specificity 99%. CONCLUSIONS: After the revision of many lesions with MBGD, we concluded that the term 'granularity' better describes this entity. Lesions with irregular granularity (periphery, irregularly distributed) should be removed especially if they are associated with red, blue or white colour. Lesions with a benign dermoscopy pattern which have granularity with a regular appearance and involving only a small portion of the lesion do not require surgical excision.

Introduction to dermoscopy.

When approaching a pigmented lesion with dermoscopy, the entire architecture of the lesion should be considered. The presence of certain pigment patterns, structural patterns, or border characteristic alone are insufficient to make the most accurate diagnosis. Because pigmented lesions are dynamic and have many variations in their patterns, there can exist no exact defining classifications among each type of pigmented lesion.

Automatic differentiation of melanoma from melanocytic nevi with multispectral digital dermoscopy: a feasibility study.

BACKGROUND: Differentiation of melanoma from melanocytic nevi is difficult even for skin cancer specialists. This motivates interest in computer-assisted analysis of lesion images. OBJECTIVE: Our purpose was to offer fully automatic differentiation of melanoma from dysplastic and other melanocytic nevi through multispectral digital dermoscopy. METHOD: At 4 clinical centers, images were taken of pigmented lesions suspected of being melanoma before biopsy. Ten gray-level (MelaFind) images of each lesion were acquired, each in a different portion of the visible and near-infrared spectrum. The images of 63 melanomas (33 invasive, 30 in situ) and 183 melanocytic nevi (of which 111 were dysplastic) were processed automatically through a computer expert system to separate melanomas from nevi. The expert system used either a linear or a nonlinear classifier. The "gold standard" for training and testing these classifiers was concordant diagnosis by two dermatopathologists. RESULTS: On resubstitution, 100% sensitivity was achieved at 85% specificity with a 13-parameter linear classifier and 100%/73% with a 12-parameter nonlinear classifier. Under leave-one-out cross-validation, the linear classifier gave 100%/84% (sensitivity/specificity), whereas the nonlinear classifier gave 95%/68%. Infrared image features were significant, as were features based on wavelet analysis. CONCLUSION: Automatic differentiation of invasive and in situ melanomas from melanocytic nevi is feasible, through multispectral digital dermoscopy.

Melanoma in a psoriatic plaque.

This is the first reported case of a melanoma in a psoriatic plaque. The clinical, dermoscopic, and histologic features of this case are detailed. A review of the risk of melanoma among patients treated with psoralen-ultraviolet A is presented.

Comparison of conventional photographs and telephonically transmitted compressed digitized images of melanomas and dysplastic nevi.

BACKGROUND: One of the most difficult problems in the in vivo diagnosis of cutaneous tumors is the differentiation clinically between early malignant melanoma (MM) and atypical (dysplastic) melanocytic nevi (AMNs) because these lesions share clinical features. High-quality digital imaging systems and store-and-forward technology have the potential for use in a teledermatology system with which experts would be able to immediately transmit their diagnostic opinions concerning these challenging lesions. OBJECTIVE: The main purpose of this study was to determine if the clinical and dermoscopic diagnoses and the dermoscopic features of AMN and early MM are unaltered after telephonic transmission of their digitized images. METHODS: Conventional and dermoscopic photographic transparencies of 22 AMNs and 9 early MMs, viewed on rearview projectors and then scanned, compressed, transmitted (Internet) and viewed on color monitors, were evaluated. RESULTS: The concordance in the diagnosis of AMN and of early MM by all four observers, both clinically and dermoscopically, when comparing rearview-projected conventional transparency slides to transmitted, compressed, digitized images, was high. For most specific dermoscopic features, the concordance was good, although less so for the presence or absence of some dermoscopic creatures, namely 'dots', 'blue/gray' color and 'red' color. CONCLUSION: The results reported support the conclusion that Internet transmission of digitized images of MMs and AMNs retains sufficient information for diagnostic purposes. This study is a step in the creation of an international teledermoscopy network for pigmented cutaneous lesions.

The actinic comedonal plaque.

A case of actinic comedonal plaque is reported. We comment on the case as well as describe the skin surface microscopic features.

Lentigo maligna. The use of rush permanent sections in therapy.

Lentigo maligna is often treated with superficial therapies that are associated with high recurrence rates. The high recurrence rates are a result of incomplete destruction or removal of tumor from clinically inapparent but histologically positive areas. We describe the use of the Mohs technique with rush permanent sections for the complete removal of this melanocytic neoplasm.

Apocrine adenocarcinoma: case report and review of the literature.

Apocrine adenocarcinoma is a rare, primary malignant neoplasm of the skin. Clinically, it is a painless, skin-colored, slow-growing, firm or cystic nodule. The tumor has a high rate of local recurrence and can metastasize. In selected cases, Mohs micrographic surgery appears to be an effective treatment. We report the first case of apocrine adenocarcinoma to occur on the fingertip, and the first to be treated with Mohs micrographic surgery.

Basal-cell carcinomas on covered or unusual sites of the body.

Basal-cell carcinomas on covered, anatomically shielded, or otherwise unusual sites of the body are rare compared to the number on constantly exposed parts of the body, but since basal-cell carcinomas are so common, instances of the former sort are not infrequently encountered. Five such cases are described and illustrated.