Immunocytological detection of isolated tumour cells in the bone marrow of malignant melanoma patients: a new method for the detection of minimal residual disease.
OBJECTIVE
Immunocytologically detected isolated tumour cells indicate a poor prognosis. This has been shown in breast, gastrointestinal and lung cancer, and might thereby help to indicate adjuvant therapy. Immunocytology has been proved to be a reliable technique and enables a phenotypic tumour cell characterization. We find this technique superior to molecular biological techniques such as reverse transcriptase polymerase chain reaction RT-PCR. So far, immunocytological studies have not been performed in malignant melanoma patients and our study aimed to establish this approach in melanoma patients.


METHODS
Twenty melanoma patients who underwent surgery for lymph-node metastasis using a radical lymphadenectomy were studied. Using the immunoperoxidase method, cytospins of bone marrow aspirates (1.5x10(6)cells per patient) were stained with the monoclonal antibody HMB-45. Nineteen patients who were surgically treated but did not suffer from malignant melanoma were included as a control group.


RESULTS
Four of the 20 patients showed isolated tumour cells in the aspirate. Three of these patients had stage IV disease. One patient had a stage III tumour (1/7; 14.3%). One patient was classified as stage II and did not show tumour cells in the bone marrow. No staining cells were found in the control group (n=19).


CONCLUSIONS
Our study demonstrates that the immunocytological approach can be used as a new technique to detect occult tumour cell dissemination in malignant melanoma patients and supports previous findings in carcinoma of the stomach, colon, pancreas and other tumours.
Thybusch-Bernhardt
A
A
Department of Surgery, Christian-Albrechts-University, Kiel, Germany.
Klomp
H J
HJ
Maas
T
T
Kremer
B
B
Juhl
H
H
D000328:Adult; D000368:Aged; D001853:Bone Marrow / Q000473:pathology*; D019046:Bone Marrow Neoplasms / Q000175:diagnosis* / Q000556:secondary*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008545:Melanoma / Q000175:diagnosis* / Q000556:secondary*; D008875:Middle Aged