Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Primary acquired melanosis (PAM), a disease that affects mostly middle-aged white patients, is predominantly a proliferative condition of the melanocytes that normally populate the conjunctival epithelium. Primary acquired melanosis without atypia (low risk for the development of melanoma) is typically created by increased numbers of melanocytes restricted to the basilar region of the epithelium without nuclear hyperchromasia or prominence of the nucleoli. Primary acquired melanosis with atypia, a formal precursor of melanoma, is characterized by the proliferation of small polyhedral cells, spindle cells, large dendritiform melanocytes, or epithelioid cells that may: remain restricted to the basilar region (basilar nests); form nests at all levels of the epithelium; spread individually to all levels of the epithelium (pagetoid extension); or proliferate in a sheet-like fashion approximating a melanoma in situ. Lesions composed of epithelioid cells or exhibiting intraepithelial pagetoid extension have, respectively, a 75 or 90% chance of eventuating in invasive melanoma. Primary acquired melanosis in an adult should not be confused with "a junctional nevus," which is almost always restricted to childhood. Invasive melanomas measuring less than 0.8 mm in thickness tend not to be associated with metastases; the tumor cells may be small polyhedral (in which case confusion with a compound nevus often arises), epithelioid, spindled, or ballooned. Nodules composed of spindle cells in part or in toto tend to have less metastatic potential at a given thickness measurement than comparable nodules composed of epithelioid or polyhedral cells. The clinical features, electron microscopic findings, and biologic principles underwriting clinical management are also presented.
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PMID:Clinicopathologic characteristics of premalignant and malignant melanocytic lesions of the conjunctiva. 264 38

Malignant melanomas of the conjunctiva are extremely rare in children. The authors report an 11-year-old boy who had a nodule at the limbus in a pigmented area since early childhood. The lesion was excised and the diagnosis of atypical compound nevus was made. Five months later, the patient returned with multiple nodules in the bulbar and palpebral conjunctiva. One of the lesions was excised, and the diagnosis was malignant melanoma. He was lost for follow-up for 6 months; then he presented a large pigmented, vascularized mass protruding through the palpebral aperture. Results of systemic workup for metastatic disease were negative, and an exenteration was performed. A few months later, cervical lymphadenopathy developed followed by extensive metastatic disease.
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PMID:Malignant melanoma of the conjunctiva. Report of a case. 368 6

Malignant melanomas normally arise at the dermoepidermal junction. Development of these tumours in deeper layers of the dermis without having contact with the junction is rare. A small congenital melanocytic nevus localized in the region of the waist band was excised because of mechanical irritation; it had not shown any changes over years. A thorough examination of the whole body did not give any clue to a malignant melanoma. Histologically a compound nevus with the typical architecture of a congenital melanocytic nevus was found. In the deeper dermis there was an isolated nodule of extremely atypical melanocytes with minimal pigmentation of melanin. S100 antigen could be demonstrated throughout the whole tumour whereas HMB45 was only found at the dermoepidermal junction. There was no marking of the tumour cells with a pancytokeratin antibody. A histological relationship between the new tumour and a mixed tumour of the left testicle, which had been excised 3 years ago, could be excluded. We did not find any metastases neither by image-aided methods nor by sentinel lymph node biopsy.
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PMID:[Occult dermal primary melanoma in congenital nevus-cell nevus]. 1124 93

12-Lipoxygenase (12-LOX), through its metabolite 12( )-hydroxyeicosatetraenoic acid [12( )-HETE], has been demonstrated to play a pivotal role in experimental melanoma invasion and metastasis, and 12-LOX expression may be important in early human melanoma carcinogenesis. We have studied the differences in 12-LOX protein expression during the progression of melanoma from human melanocytic cells to benign and dysplastic naevi to malignant metastatic disease. 12-LOX expression was determined in normal human skin melanocytes and in melanocytes found in compound naevi, dysplastic naevi and melanomas using a platelet-type 12-LOX antibody with a diaminobenzidine immunoperoxidase system detection system and was quantified using the analysis software NIH Image 1.62. Mean cellular pixel densities for 12-LOX staining ( = 50 cells/histological type) were unchanged in compound naevi ( = 0.14) and were increased in dysplastic naevi and melanomas compared with normal skin melanocytes ( = 0.03 and = 0.01, respectively). Similarly, melanomas had higher levels of expression compared with dysplastic naevi ( = 0.03). 12-LOX expression was significantly different between compound naevus and dysplastic naevus melanocytes ( = 0.01). These data suggest that 12-LOX may be an important novel marker for cancer progression within the melanoma system, and therefore could be a useful biomarker and therapeutic target for melanoma chemoprevention.
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PMID:Expression of 12-lipoxygenase as a biomarker for melanoma carcinogenesis. 1239 83

We report 4 cases of melanoma localized on the sole with some striking histological similarities to the compound nevi. One case showed inguinal lymph node metastases after a diagnosis of compound nevus made 5 years earlier. The other 3 cases were sent to us in consultation as suspected plantar lesions; a diagnosis of melanoma mimicking compound nevus was proposed: the sentinel lymph node technique was accordingly performed and resulted positive. These 4 index cases were compared with 26 cases of ordinary plantar melanoma and with 117 cases of benign compound plantar nevi. Histologically, the similarity of areas of these 4 cases of plantar melanoma to compound plantar nevi (namely Miescher, Clark, or acral lentiginous nevus) is so close that it may prove misleading in the diagnostic pathway. In such cases, an erroneous diagnosis of benign lesion may be made. The correct diagnosis of melanoma can, however, be done by combining the clinical and pathological findings. In fact, this deceptive form of melanoma mimicking a compound nevus is characterized by patients' advanced age (>45 years), large lateral diameters (>10 mm), and significant depth of the lesion (>1 mm). In our 4 cases, such features were combined with one or more of the following histological clues: lentiginous (ie, continuous) proliferation of enlarged and hyperchromatic melanocytes aligned in single units at the dermoepidermal junction; extensive eccrine duct melanocytic infiltration; dermal melanocytes with slight nuclear enlargement, nuclear membrane thickening and folding, and conspicuous central nucleoli; and cellular pleomorphism of the epidermal and dermal component. Moreover, mitotic figures were an inconstant but decisive indication of malignancy. In conclusion, a small group of plantar melanoma has striking similarities with compound nevi. Only the correlation of clinical data (old age of the patient and large size of the lesion) with subtle architectural and cytological alterations (depth of the lesion, lentiginous melanocytic epidermal and eccrine proliferation, and cellular alteration and mitoses) allows a correct diagnosis.
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PMID:Plantar melanoma that mimics melanocytic nevi: a report of 4 cases with lymph node metastases and with review of positive and negative controls. 1931 96