Quantification of melanoma micrometastases in sentinel lymph nodes using real-time RT-PCR.
Detection of micrometastases in the regional tumor-draining lymph nodes is critical for staging and prognosis in melanoma patients. We applied a quantitative multiple-marker RT-PCR assay to improve the detection of occult melanoma cells in the sentinel lymph node (SLN). From 139 patients with primary cutaneous melanoma who underwent sentinel lymphadenectomy, a total of 235 SLN were assessed for Melan-A and tyrosinase expression by real-time quantitative RT-PCR. Twenty-three patients (17%) were positive by histopathology and expressed messenger RNA of one or two markers. Of the patients with histopathologically negative SLN 39 (28%) were reclassified by positive RT-PCR. Patients were examined for tumor recurrences during a median follow-up period of 29 mo. Tumor recurrences were demonstrated in eight patients (35%) with histopathologically positive SLN, in four patients (10%) with submicroscopic tumor cells detected exclusively by real-time RT-PCR, and in none of the patients negative by both methods. The differences in recurrence rates were statistically significant (p=0.01). These data indicate that real-time quantitative RT-PCR for the detection of minimal residual melanoma in SLN improves the prediction of disease-free survival.
Giese
Thomas
T
Institute of Immunology, University of Heidelberg, Heidelberg, Germany. Thomas.Geise@urz.uni-heidelberg.de
Engstner
Monika
M
Mansmann
Ulrich
U
Hartschuh
Wolfgang
W
Arden
Bernhard
B
D000951:Antigens, Neoplasm / Q000235:genetics; D018572:Disease-Free Survival; D005500:Follow-Up Studies; D005820:Genetic Testing / Q000379:methods; D006801:Humans; D008197:Lymph Node Excision; D008207:Lymphatic Metastasis; D058965:MART-1 Antigen; D008545:Melanoma / Q000453:epidemiology / Q000235:genetics / Q000556:secondary*; D014442:Monophenol Monooxygenase / Q000235:genetics; D009363:Neoplasm Proteins / Q000235:genetics; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology / Q000235:genetics / Q000473:pathology; D018365:Neoplasm, Residual / Q000453:epidemiology / Q000235:genetics / Q000473:pathology; D011237:Predictive Value of Tests; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*; D012307:Risk Factors; D021701:Sentinel Lymph Node Biopsy; D012878:Skin Neoplasms / Q000453:epidemiology / Q000235:genetics / Q000473:pathology*
D000951:Antigens, Neoplasm; D058965:MART-1 Antigen; C548667:MLANA protein, human; D009363:Neoplasm Proteins; D014442:Monophenol Monooxygenase