Melanocytic tumors of uncertain malignant potential
Encyclopedia
Melanocytic tumors of uncertain malignant potential (MELTUMP) are melanocytic
lesion
s in the dermis
that cannot be classified by morphology
as either benign naevi (moles) or malignant melanoma
s because the mass shows features of both.
Several lesion types may be classified as MELTUMPs: these include atypical melanocytic proliferations with features that may overlap with atypical Spitz naevi/tumors, dysplastic naevi, pigmented epithelioid melanocytoma, deep penetrating naevi, congenital neavi, cellular nodules in congenital naevi, possible naevoid melanomas, and cellular blue naevi.
A related category of melanocytic proliferation is superficial atypical melanocytic proliferations of uncertain significance (SAMPUS). This category, unlike MELTUMP, which implies as yet undetermined potential for metastases even after complete excision, signifies lesions without metastatic potential at time of excision but with potential to progress upon incomplete excision. The SAMPUS category includes certain atypical junctional melanocytic proliferations and proliferations in both the epidermis and papillary dermis that are not accompanied by intradermal tumorigenic architecture or cell mitosis
.
Melanocyte
-External links: - "Eye: fovea, RPE" - "Integument: pigmented skin"...
lesion
Lesion
A lesion is any abnormality in the tissue of an organism , usually caused by disease or trauma. Lesion is derived from the Latin word laesio which means injury.- Types :...
s in the dermis
Dermis
The dermis is a layer of skin between the epidermis and subcutaneous tissues, and is composed of two layers, the papillary and reticular dermis...
that cannot be classified by morphology
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
as either benign naevi (moles) or malignant melanoma
Melanoma
Melanoma is a malignant tumor of melanocytes. Melanocytes are cells that produce the dark pigment, melanin, which is responsible for the color of skin. They predominantly occur in skin, but are also found in other parts of the body, including the bowel and the eye...
s because the mass shows features of both.
Several lesion types may be classified as MELTUMPs: these include atypical melanocytic proliferations with features that may overlap with atypical Spitz naevi/tumors, dysplastic naevi, pigmented epithelioid melanocytoma, deep penetrating naevi, congenital neavi, cellular nodules in congenital naevi, possible naevoid melanomas, and cellular blue naevi.
A related category of melanocytic proliferation is superficial atypical melanocytic proliferations of uncertain significance (SAMPUS). This category, unlike MELTUMP, which implies as yet undetermined potential for metastases even after complete excision, signifies lesions without metastatic potential at time of excision but with potential to progress upon incomplete excision. The SAMPUS category includes certain atypical junctional melanocytic proliferations and proliferations in both the epidermis and papillary dermis that are not accompanied by intradermal tumorigenic architecture or cell mitosis
Mitosis
Mitosis is the process by which a eukaryotic cell separates the chromosomes in its cell nucleus into two identical sets, in two separate nuclei. It is generally followed immediately by cytokinesis, which divides the nuclei, cytoplasm, organelles and cell membrane into two cells containing roughly...
.