Use of New Techniques in Addition to IHC Applied to the Diagnosis of Melanocytic Lesions, With Emphasis on CGH, FISH, and Mass Spectrometry

A triple combination of latanoprost, fractional CO2 laser, and platelet-rich plasma in localized vitiligo: A clinical and histopathologic study

BACKGROUND

Several treatment modalities are available for the treatment of vitiligo due to the lack of a uniformly effective therapy. Topical latanoprost 0.005% is an effective topical treatment. Fractional CO2 laser alone or combined with platelet-rich plasma (PRP) has been proposed as effective adjunctive therapies.

OBJECTIVES

We aimed to compare the efficacy of topical latanoprost 0.005% (Ioprost®, Orchidia, Egypt) combined with either add-on fractional CO2 laser or fractional CO2 -PRP versus topical latanoprost monotherapy in the treatment of localized stable vitiligo.

PATIENTS/METHODS

The study included 60 patients randomly assigned into three equal groups. Group A patients received topical latanoprost drops only. Group B patients received topical latanoprost drops and fractional CO2 laser sessions at 2-week interval for 3 months. Group C patients received topical latanoprost drops and fractional CO2 laser sessions combined with PRP at a 2-week interval for 3 months. The mean improvement score by the physician was calculated 4 months after the start of the study. Punch skin biopsies were obtained before treatment and 4 months from the beginning of the study and stained with H&E and HMB-45 antibody for evaluation of pigmentation.

RESULTS

Significant clinical improvement of vitiligo lesions with significant increase of re-pigmentation were reported in the three treated groups. Latanoprost in combination with fractional CO2 and PRP was associated with more significant therapeutic outcomes than either combined latanoprost and fractional CO2 or latanoprost alone.

CONCLUSION

Fractional CO2 laser-PRP enhances the therapeutic efficacy of latanoprost 0.005% in the treatment of localized stable vitiligo.

[Histopathological interpretation of biopsies for melanocytic tumours in unusual locations]

INTRODUCTION AND OBJECTIVE

Melanoma is the leading cause of death from skin cancer in the world. Despite the advances in molecular diagnosis, the differential diagnosis between melanoma and benign melanocytic tumors relies on histopathology. However, not all of the criteria for the microscopy of a biopsy of a melanocytic tumor are applicable to all locations.

PATIENTS

We highlight these difficulties in the presentation of 2cases of melanocytic tumors in unusual locations which were diagnostically challenging.

RESULTS

After analyzing the relevant literature, the atypical histopathological characteristics of melanocytic tumors could be specified for unusual anatomical sites.

Diagnostic error, uncertainty, and overdiagnosis in melanoma

Diagnostic error can be defined as deviation from a gold standard diagnosis, typically defined in terms of expert opinion, although sometimes in terms of unexpected events that might occur in follow-up (such as progression and death from disease). Although diagnostic error does exist for melanoma, deviations from gold standard diagnosis, certainly among appropriately trained and experienced practitioners, are likely to be the result of uncertainty and lack of specific criteria, and differences of opinion, rather than lack of diagnostic skills. In this review, the concept of diagnostic error will be considered in relation to diagnostic uncertainty, and the concept of overdiagnosis in melanoma will be presented and discussed.

Liposomes Loaded with Amaranth Unsaponifiable Matter and Soybean Lunasin Prevented Melanoma Tumor Development Overexpressing Caspase-3 in an In Vivo Model

The objective of this study was to assess the effectiveness of liposomes loaded with soybean lunasin and amaranth unsaponifiable matter (UM + LunLip) as a source of squalene in the prevention of melanoma skin cancer in an allograft mice model. Tumors were induced by transplanting melanoma B16-F10 cells into the mice. The most effective treatments were those including UM + LunLip, with no difference between the lunasin concentrations (15 or 30 mg/kg body weight); however, these treatments were statistically different from the tumor-bearing untreated control (G3) (p < 0.05). The groups treated with topical application showed significant inhibition (68%, p < 0.05) compared to G3. The groups treated with subcutaneous injections showed significant inhibition (up to 99%, p < 0.05) in G3. During tumor development, UM + LunLip treatments under-expressed Ki-67 (0.2-fold compared to G3), glycogen synthase kinase-3β (0.1-fold compared to G3), and overexpressed caspase-3 (30-fold compared to G3). In addition, larger tumors showed larger necrotic areas (38% with respect to the total tumor) (p < 0.0001). In conclusion, the UM + LunLip treatment was effective when applied either subcutaneously or topically in the melanoma tumor-developing groups, as it slowed down cell proliferation and activated apoptosis.

Diagnosis of melanoma by imaging mass spectrometry: Development and validation of a melanoma prediction model

BACKGROUND

The definitive diagnosis of melanocytic neoplasia using solely histopathologic evaluation can be challenging. Novel techniques that objectively confirm diagnoses are needed. This study details the development and validation of a melanoma prediction model from spatially resolved multivariate protein expression profiles generated by imaging mass spectrometry (IMS).

METHODS

Three board-certified dermatopathologists blindly evaluated 333 samples. Samples with triply concordant diagnoses were included in this study, divided into a training set (n = 241) and a test set (n = 92). Both the training and test sets included various representative subclasses of unambiguous nevi and melanomas. A prediction model was developed from the training set using a linear support vector machine classification model.

RESULTS

We validated the prediction model on the independent test set of 92 specimens (75 classified correctly, 2 misclassified, and 15 indeterminate). IMS detects melanoma with a sensitivity of 97.6% and a specificity of 96.4% when evaluating each unique spot. IMS predicts melanoma at the sample level with a sensitivity of 97.3% and a specificity of 97.5%. Indeterminate results were excluded from sensitivity and specificity calculations.

CONCLUSION

This study provides evidence that IMS-based proteomics results are highly concordant to diagnostic results obtained by careful histopathologic evaluation from a panel of expert dermatopathologists.

Mucosal Melanomas of the Anogenital Tract: Clinical and Pathologic Predictors of Patient Survival

Primary anogenital mucosal melanomas (AGMs) are rare aggressive malignancies that are typically diagnosed at an advanced stage. Ulceration is a common feature in AGMs and may not correlate with outcome. Therefore, staging of AGMs similar to primary cutaneous melanomas, based on tumor thickness and ulceration, may not robustly predict outcome. Derivation of site-specific staging systems is essential for prognostication and optimal management of these patients. To this end, recent retrospective studies have revealed tumor thickness (TT) and mitotic rate (MR) as features of most prognostic significance as follows: in anorectal (TT only) and vulvar (TT and MR) melanomas.

Medical Malpractice Issues in Dermatology: Clinical Safety and the Dermatologist

Clinical safety and medical liability are first-order concerns in today's medical practice. It is important to understand the circumstances under which medical acts fail to live up to the accepted standard of care and to recognize the impact that malpractice claims have on physicians. Practitioners must also grasp the concept of medical error, studying malpractice claims in order to identify the areas where improvement is needed. The risk of accusations of malpractice in dermatology is comparatively low, both in Spain and worldwide. However, a great variety of clinical scenarios in dermatology can potentially give rise to a claim, and malignant melanoma is most susceptible to risk. Dermatologists should know which actions during clinical consultation merit particular attention and care. Clinical practice carries inherent risk of malpractice claims, but taking certain recommended precautions can prevent them.