Pseudoxanthoma-elasticum-like changes on the soft palate.

Pseudoxanthoma elasticum (PXE) is an autosomal recessive genetic disorder characterized by aberrant fragmentation and calcification of elastic fibers, leading to characteristic cutaneous, ophthalmic, and cardiovascular manifestations. PXE demonstrates significant phenotypic variability; involvement of the oral mucosa may be the only clue to the diagnosis. Reports on mucous membrane involvement in PXE are scarce. Here, we present a case of PXE-like changes in the oral cavity. A 70-year-old male patient presented with a painless leukoplakic lesion on the soft palate. Biopsy revealed numerous degenerated fibers in the lamina propria. Verhoeff-van Gieson and von Kossa staining confirmed their identity as calcified elastic fibers. A histopathological diagnosis of PXE-like changes was made; the patient was referred to ophthalmology where angioid streaks were visualized fundoscopically. PXE-like changes in the absence of the characteristic genetic mutation have also been reported with or without systemic manifestations. Furthermore, PXE-like changes have been reported in up to 10% of oral biopsy specimens undertaken without clinical suspicion for PXE. Therefore, the significance of such changes in isolation is unclear. Clinicians and pathologists should be aware of the potential oral manifestations of PXE to facilitate prompt diagnosis and subspecialist referral.

Extramammary myofibroblastoma of the oral cavity.

Myofibroblastoma is a rare, benign mesenchymal tumor first described as a neoplasm of the breast. Extramammary myofibroblastoma is a histopathologically and genetically identical lesion occurring outside the breast. Herein is presented a case of extramammary myofibroblastoma arising in the oral cavity. A 59-year-old woman presented with a 1.5 cm nodule on the buccal surface of the lower lip. Wide local excision was performed. Histopathologic examination revealed haphazard fascicles of monomorphic spindle cells with hyalinized collagen bundles without fat. The spindled cells were diffusely positive for CD34, and focally for progesterone receptor. Desmin, smooth muscle actin, estrogen receptor, androgen receptor, S100, and STAT6 were negative. Rb1 expression was lost in tumor cells. Thus, the diagnosis of extramammary myofibroblastoma was made. Differential diagnoses include spindle-cell lipoma and angiofibroma. All three tumors are members of the 13q14 deletion/RB1 loss family. Indolent but locally aggressive (solitary fibrous tumor, desmoid fibromatosis) and frankly malignant (low-grade peripheral nerve sheath tumor, dermatofibrosarcoma protuberans) entities can be excluded by immunohistochemistry and careful microscopic examination. Extensive sampling extramammary myofibroblastoma is important to exclude the possibility of malignancy. Clinicians and pathologists alike should be aware of this entity and its potential to arise rarely in unusual locations.

Artificial intelligence and melanoma: A comprehensive review of clinical, dermoscopic, and histologic applications.

Melanoma detection, prognosis, and treatment represent challenging and complex areas of cutaneous oncology with considerable impact on patient outcomes and healthcare economics. Artificial intelligence (AI) applications in these tasks are rapidly developing. Neural networks with increasing levels of sophistication are being implemented in clinical image, dermoscopic image, and histopathologic specimen classification of pigmented lesions. These efforts hold promise of earlier and highly accurate melanoma detection, as well as reliable prognostication and prediction of therapeutic response. Herein, we provide a brief introduction to AI, discuss contemporary investigational applications of AI in melanoma, and summarize challenges encountered with AI.