A case of classic adult pityriasis rubra pilaris successfully treated with a combination of acitretin and ustekinumab: A case report.

Classic adult pityriasis rubra pilaris is a severe papulosquamous disease that tends to resolve in 3-5 years but can have a devastating impact on patients while active. It shares features with psoriasis, but treatment remains largely empiric, based on case reports and series. The condition is often refractory to treatment, especially initially, with topical corticosteroids and oral acitretin the more commonly employed agents. Relatively high doses of acitretin are needed for adequate response, and adverse events often limit adherence. Given the similarity to psoriasis, biologic agents approved for psoriasis have been used with good effect in classic adult pityriasis rubra pilaris and show better tolerance than other agents. In this report, we describe the successful use of a combination of acitretin and ustekinumab in a case of classic adult pityriasis rubra pilaris.

Malignant Melanoma With Osteoclast-Like Differentiation.

Osteoclast-like giant cells are frequently encountered in nonskeletal malignancies; however, the evidence to date suggests that they represent a tissue response to the lesion rather than neoplastic differentiation. We describe a case of metastatic melanoma demonstrating osteoclast-like differentiation in the lung. The lung nodule was diagnosed as a metastatic melanoma by histological features and confirmed by immunohistochemistry. Resection specimen showed numerous multinucleated giant cells exhibiting osteoclast-like morphology dispersed throughout the lesion. Both the neoplastic melanocytes and giant cells were reactive for HMB-45, Melan-A, and S100. In addition, the multinucleated neoplastic giant cells were also reactive for the monocyte/macrophage lineage markers CD68 and CD163, and alkaline phosphatase, an enzyme present in normal osteoclasts. The neoplastic melanocytes and the multinucleated neoplastic giant cells were also reactive for microphthalmia-associated transcription factor, a protein required for the development of both melanocytes and osteoclasts. Collectively, a co-expression of monocyte/macrophage markers along with melanocytic markers and alkaline phosphatase in the multinucleated neoplastic giant cells in metastatic melanoma suggest that malignant melanocytes are capable of differentiating into osteoclast-like cells and consequently aid invasion into various structures and eliciting the aggressive behavior.

Nuclear morphometry in flat epithelial atypia of the breast as a predictor of malignancy: a digital image-based histopathologic analysis.

OBJECTIVE: To identify morphometric features unique to flat epithelial atypia associated with cancer using digital image analysis. STUDY DESIGN: Cases with diagnosis of flat epithelial atypia were retrieved and divided into 2 groups: flat epithelial atypia associated with invasive or in situ carcinoma (n = 31) and those without malignancy (n = 27). Slides were digitally scanned. Nuclear features were analyzed on representative images at 20x magnification using digital morphometric software. RESULTS: Parameters related to nuclear shape and size (diameter, perimeter) were similar in both groups. However, cases with malignancy had significantly higher densitometric green (p = 0.02), red (p = 0.03), and grey (p = 0.02) scale levels as compared to cases without cancer. A mean grey densitometric level > 119.45 had 71% sensitivity and 70.4% specificity in detecting cases with concomitant carcinoma. CONCLUSION: Morphometry of features related to nuclear staining appears to be useful in predicting risk of concurrent malignancy in patients with flat epithelial atypia, when added to a comprehensive histopathologic evaluation.