Skin, Malignant melanoma, nodular type [LMP11473]

LMP11473 Thumbnail
View the Zoomify Image
Image Details
Diagnostic Modality: 
Whole Slide Image
Disease Category: 
Neoplasia
Diagnosis: 
Malignant melanoma, nodular type
Species: 
Human
Organ System: 
Skin
Gender: 
Male
Age: 
41 years
Diagnosis Code: 
ICD-10: C43 | ICD-O: 8721/3
Slide Contributor Information
Forse, C., Ghazarian, D.

Keywords

melanoma, nodular

Clinical History

Rapidly expanding pigmented papule on the back.

Clinical Discussion

Nodular melanoma is a subtype of malignant melanoma which occurs exclusively in the vertical growth phase. The overlying epidermis is often thinned and effaced and may not have the upward pagetoid spread characteristic of other melanoma subtypes. The tumour is composed of epithelioid to spindled cells which form nests in the dermis. The melanocytes are pleomorphic and do not show maturation with increasing depth. Note the extensive pigmentation (melanin granules) in the malignant cells at the margin of the shave biopsy.

Once a melanoma is excised, the specimen must be examined for the following important features: 1) tumour depth (Breslow thickness); 2) number of mitoses; 3) evidence of tumour regression; 4) ulceration of epidermis; 5) the presence and amount of tumour infiltrating lymphocytes; 6) lymphovascular invasion; 7) microsatellitosis. The three most important prognostic factors are tumour depth, increased mitotic rate and ulceration.