Analysis of BRAF mutations in circulating tumor cells selected by size from patients with melanoma and comparision to the primary tumor
| Autor: | Naoual Benali-Furet, Fei Ye, Yvon E. Cayre, Marie Odile North, Janine Wechsler, Agnès Carlotti, Isbou Paraiso, F. Boitier, Marie-Françoise Avril, Eric Clauser |
|---|---|
| Rok vydání: | 2012 |
| Předmět: | |
| Zdroj: | Journal of Clinical Oncology. 30:e21014-e21014 |
| ISSN: | 1527-7755 0732-183X |
| DOI: | 10.1200/jco.2012.30.15_suppl.e21014 |
| Popis: | e21014 Background: The efficacy of anti-BRAF therapies in patients with melanoma has emphasized the need to identify BRAF mutations in the tumour. As circulating tumour cells (CTC) derive from the primary tumour (PT), their analysis may represent a non-invasive tool to follow the molecular-target in blood after tumour removal. Methods: This prospective study included 26 patients: 24 patients had confirmed melanoma, 2 patients had benign lesions (1 naevus and 1 pyogenic granuloma). Blood samples were taken at time of the PT surgical excision; 12 healthy donors were included as controls. The 24 patients, 13 females and 11 males, had invasive melanoma (13 superficial spreading melanoma, 7 nodular melanoma, 1 lentigo malignant melanoma, 1 desmoplastic melanoma, 2 unclassified melanoma.). The mean thickness was 7.8 mm. Cytology, immunophenotyping and analysis of BRAF mutations on exon 15 were performed comparatively in primary tumour and CTC from the same patient. CTC were selected by the ScreenCell method, a single-use innovative system to isolate rare tumour cells through a filter-membrane on the basis of their size. Nucleic acids DNA/RNA were extracted from live CTC after filtration. Results: Isolated CTC and microemboli were found in 21/24 patients and were found comparable to the primary melanoma cells. No CTC was found in 10 healthy donors and 2 patients with benign lesions. The mean number of CTC was 2 CTC per ml, the maximum was 4 CTC and 7 microemboli per ml. Malignancy of CTC was assessed on classic criteria: cell size larger than 15 microns, nucleo-cytoplasmic ratio > 0.5, presence of clusters composed of pleomorphic cells. CTC were positively immunostained either by S-100 or MART1/melanA or HMB45 antibodies; 4 patients were studied for BRAF mutations in both melanoma and CTC. The results (2 negative and 2 positive) were concordant in primary melanoma cells and CTC. The V600E-BRAF mutation was found in the 2 positive cases. Conclusions: The ScreenCell method of CTC selection by size allows to detect BRAF mutations in CTC of patients with melanoma. This simple method could be proposed to follow the molecular-target during the course of evolution and treatment after tumour removal. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|