Histopathological features of molluscum contagiosum other than molluscum bodies

Abstract

Perilesional fibroedematous to fibromyxoid stroma and keratinocyte changes, including prominent nucleoli and amphophilic cytoplasm with clear vacuolization, are common in MC. Recognizing these features may prove helpful in reaching the diagnosis of MC in cases lacking classic histopathological features on initial sections.

Handheld reflectance confocal microscopy for the diagnosis of molluscum contagiosum: Histopathology and dermoscopy correlation

“…The well‐circumscribed area consisting of hypo‐refractive roundish lobules in the central portion of the lesions corresponds with the typical histopathologic features of well‐defined, lobulated, endophytic hyperplasia, with fibrous septa between the lobules as the result of the papillae being compressed by the epidermal growth (Fig. c) . This finding also correlates with the central polylobular white to yellow amorphous structure observed by dermoscopy.…”

“…They generally occur on the face, trunk and extremities in children and on genitalia in young adults as a sexually transmitted disease. The diagnosis of MC is usually based on the typical clinical appearance, but some lesions may have an unusual morphology or can be located in uncommon body sites, making clinical diagnosis difficult and requiring excision with histopathological confirmation . Dermoscopy is routinely used for supporting the clinical diagnosis, showing a characteristic pattern consisting of a central polylobular white to yellow amorphous structure with a peripheral crown of reddish, linear or branched vessels .…”

2020 European guideline on the management of genital molluscum contagiosum

“…Immunohistochemical studies, however, are used only for clinico‐pathological research and never for diagnostic purposes. Perilesional fibro‐oedematous to fibromyxoid stroma and rarely amyloid‐like change or anetoderma or metaplastic ossification may occur 84,85 . Follicular induction in the adjacent epidermis should not be mistaken for a basal cell carcinoma 86 .…”

Molluscum contagiosum mimicking sebacious hyperplasia

“…Presentation in immunocompromised patients, older patients and patients with presentation in the head and neck may be difficult to diagnose clinically [3].…”

“…These can grow so large that they often displace the nuclei peripherally and can range from eosinophilic to basophilic in color. They initially are found in the keratinocytes near the basal layer then progress toward the more superficial layers of the epidermis [3].…”