Immunomagnetic detection of micrometastatic cells in bone marrow of uveal melanoma patients: a paradox
Our objective was to study survival rates with the bone marrow (BM) results in a cohort of uveal melanoma patients with long follow-up.Methods:
Mononuclear cell fractions isolated from BM were examined for tumour cells using our immunomagnetic separation (IMS) method. The patients were classified as BM positive or BM negative. Clinical follow-up, histopathological findings, vital status and cause of death were registered.Results:
The study included 328 consecutive patients with uveal melanoma from 1997 to 2006. Tumour cells were found in BM samples in 29% (95% CI, 25–34) at enrolment (96 cases). After a minimum follow-up time of 6 years, 156 (48%) (95% CI, 42–53) melanoma patients had died. The causes were as follows: melanoma metastases 92 (59%), another cancer 20 (13%) and non-cancer 44 (28%). Nine patients were still living with melanoma metastases. Until the latest work-up, 101(31%) (95% CI, 26–36) patients had developed melanoma metastases. Cyto- or histopathological verification of the metastatic lesions was obtained in 85 cases (84%). In the group with melanoma metastases, 28 tested BM positive at study entry (28%) (95% CI, 19–38). In total, 39 of 101 with metastases tested positive at least once after a maximum of three tests (39%) (95% CI, 29–49). The overall median survival from the first BM test was shorter for the BM negative patients (9.5 years) compared with the BM positive (14.4 years), p = 0.02, log rank test.Conclusion:
Ocular melanoma cells detected in BM seem to have a positive prognostic impact on survival in contrast to our original hypothesis.