(3-8,16) Historically, three main subtypes of melanoma including superficial spreading melanoma (SSM), lentigo maligna melanoma (LMM) and
nodular melanoma (NM) were first described in 1969; (9) desmoplastic melanoma (DM) was added in 1971; (12) and acral lentiginous melanoma (ALM) was introduced in 197710 and defined in 1980.
The findings raise the possibility that these lesions are recognizable precursors of
nodular melanoma, he said.
(465,466) Other studies (453,455,462,464,471) have suggested that NRAS mutations are more frequently seen in
nodular melanomas. In addition, there is a correlation between increased tumor thickness and NRAS mutation, which mirrors the higher percentage of NRAS mutations in
nodular melanoma.
The most common scenarios in melanoma litigation cases include
nodular melanoma being misdiagnosed by a clinician or pathologist; a partial biopsy not capturing the most diagnostically relevant part of the lesion; malignant melanoma being misdiagnosed as a dysplastic or spitz nevus; unrecognized desmoplastic malignant melanoma; and metastatic malignant melanoma with an unknown primary or recurrence of melanoma (Am.
The most common scenarios in melanoma litigation cases include
nodular melanoma being misdiagnosed by a clinician or pathologist, a partial biopsy not capturing the most diagnostically relevant part of the lesion, malignant melanoma being misdiagnosed as a dysplastic or spitz nevus, unrecognized desmoplastic malignant melanoma, and metastatic malignant melanoma with an unknown primary or recurrence of melanoma (Am.
But these criteria do not apply to
nodular melanomas, which typically are round, elevated, red or pink, and uniform in color throughout.
Initially, 3 experts interpreted the lesion as a
nodular melanoma, while 1 considered it a DPN.
Superficial spreading and
nodular melanoma are the most common types in children.
Marghoob does not recommend following lesions in which the differential diagnosis includes
nodular melanoma. The article should have stated that "lesions should be biopsied when the differential diagnosis, no matter how remote, includes
nodular melanoma.
In superficial spreading or
nodular melanoma, epithelioid cells show severe degree of epithelioid cell atypia.
*
Nodular melanoma misdiagnosed as a nevus by the pathologist.
When the VGP appears de novo without preexisting RGP, it manifests as
nodular melanoma. Histologically, the VGP that supervenes on RGP appears as a new cell population with metastatic capability that determines the clinical course.
