Melanoma, tumor markers

In phase I clinical trials 47 patients, all of whom had previously failed standard treatments for solid tumors, received the drug in the UK, Italy, and Switzerland on three different schedules.123,124 Dose-limiting toxicities have been defined as bone marrow depression and diarrhea. The latter is treatable with loperamide. Signs of biological activity were seen. Notably one patient with metastatic pancreatic cancer showed a partial response (for 4 months) and two further patients, one with metastatic melanoma and one with bronchoalveolar carcinoma, also showed partial responses. In a phase I trial in combination with 5-FU, a partial response in breast cancer was observed.125 Furthermore, a reduction in tumor marker levels was observed in two patients, one with ovarian cancer, and one with colon cancer. Phase II studies have shown partial responses in cisplatin-resistant ovarian and nonsmall-cell lung cancer.126,127 The indications are that the profile of clinical activity is different and complementary to the mononuclear platinum agents. 

Carbohydrate tumor marker tumor-related antigen GM3 1998 A Detection level of <10 cells, melanoma cells diluted in 2 million healthy blood lymphocytes Zhang et al. [96]... 

Measurement of Plasma l-DOPA and L-Tyrosine by High-Performance Liquid Chromatography as a Tumor Marker in Melanoma... 

The present review will focus on the analysis of l-DOPA and L-tyrosine by HPLC in plasma. Both are involved in the first step of melanogenesis controlled by a melanocyte-specific enzyme, tyrosinase. The plasma L-DOPA/L-tyrosine ratio has been evaluated as a tumor marker in melanoma during a 10-year collaboration between the Biochemistry Laboratory, the Dermatology Department of Saint-Louis Hospital (AP-HP) in Paris (France) and the Dermatology Department of the National Center of Oncology in Sofia (Bulgaria). 

Some gangliosides of the globo series (Globo-H, sLcx hexasaccharyl ceramide, etc.) are useful cancer cell markers because they are elevated in the membranes of certain types of tumor cells such as melanomas and metastatic brain tumors. A number of GSLs play a role as tumor-associated carbohydrate antigens (TACAs)... 

Table 7 lists S-100-positive tumors and their positivity with additional markers. Myelin basic protein (MBP) (30) is a single-chain polypeptide associated with the central and peripheral nervous system. Glial fibrillary acidic protein (GFAP) and neurofilament proteins (NFP) are intermediate filaments associated with glial cells and neural cells, respectively. HMB-45 is a mouse monoclonal antibody that reacts with an antigen present in premelanosomes. It is highly sensitive and specific for melanomas and certain nevi (junctional, congenital, blue nevi). EMA has been discussed in Section 3.1.3.1. 

S-100 protein reactivity generally should be considered as melanomas. This is especially true if concomitant positivity is obtained for HMB-45, HMB-50, tyrosinase, or MART-1, because the latter four markers are only rarely associated with nerve sheath tumors. Despite the production of collagen type IV by nerve sheath cells, the immunohistochemical detection of this marker has limited value in the diagnosis of schwannian neoplasms because cells with smooth muscle, endothelial, and myo-fibroblastic differentiation may also synthesize it. 

CD30, the most consistent marker of H/RSCs, is readily detected in formalin-fixed, paraffin-embedded tissues. " However, tumor cells in some nonlymphoid malignancies, including embryonic carcinoma, melanoma. 

FIGURE 7.16 Immunolabeling for tyrosinase in sarcomatoid melanoma less than 10% of examples of this tumor variant stain for melanocytic markers other than S-100 protein. 

In specific reference to the expression of melanocytic markers in metastatic tumors, Plaza and colleagues °° have demonstrated that there is little if any antigenic drift as compared with primary melanoma. 

The ability of melanoma to simulate the appearance of various soft tissue sarcomas is also well documented. These include malignant peripheral nerve sheath tumors, gastrointestinal stromal tumors, epithelioid angiosarcoma, rhabdoid tumors, osteosarcomas, and primitive neuroectodermal tumors, to name a few. The detailed immunophenotypic properties of those lesions are provided elsewhere in this book. However, none of them manifests reactivity for gplOO-related melanocytic markers or tyrosinase, making those markers essential to the differential diagnostic process. 

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