Which subtype of malignant melanoma is characterised by absence of a recognisable radial (horizontal) growth phase, presenting as a rapidly enlarging nodule?

• A Desmoplastic melanoma
• B Superficial spreading melanoma
• C Nodular melanoma ✓
• D Acral lentiginous melanoma

Explanation

Nodular melanoma grows vertically from the outset, so it presents as a rapidly enlarging nodule that is often amelanotic and reaches greater Breslow thickness at diagnosis than other subtypes. Superficial spreading and lentigo maligna melanomas both pass through a prolonged intraepidermal radial growth phase before invasion, which is exactly the feature nodular melanoma lacks.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.