Clinical significance of the molecular detection of melanoma cells circulating in the peripheral blood in melanoma patients.

BACKGROUND: Blood circulating melanoma cells may be important for the spread of the disease. The current methods are not sensitive in detecting micro metastases. Tyrosinase mRNA can be detected in peripheral blood by a molecular test. As tyrosinase is expressed only in melanocytes and melanocytes normally do not circulate in the blood, the test may prove reliable in detecting circulating melanoma cells. EXPERIMENTAL DESIGN: we used a reverse-transcription polymerase chain reaction (RT-PCR) detecting tyrosinase mRNA in the blood. A prospective investigation in melanoma patients undergoing surgery was conducted; follow-up duration was 12 months. SETTING: University Department Laboratory and Melanoma Clinic of a Tertiary Hospital. PATIENTS: a total of 27 Greek patients with a diagnosis of malignant melanoma at different stages of the disease; 12 months follow-up after surgery. Samples form 12 healthy volunteers and 13 patients with chronic myelogenous leukemia served as controls. INTERVENTIONS: none. MEASURES: none. RESULTS: We detected mRNA tyrosinase in the peripheral blood in 16 out of 27 melanoma patients studied. No tyrosinase mRNA was detected in any of the 25 samples from the controls. Two of the 16 positive cases developed a metastasis within the next 12 months following testing. The other 14 positive cases remain metastasis free for this period, as also did the test negative cases. CONCLUSIONS: Detection of blood circulating melanoma cells by a RT-PCR technique, may be helpful in defining melanoma patients who are at risk for the spread of the disease.

Primary hydatid disease of the infratemporal fossa and the parotid gland.

Hydatid disease should be considered in the differential diagnosis of lesions causing swelling of the parotid area or exophthalmos in patients originating from countries where the incidence of the disease is high. An unusual case of hydatid disease located in the infratemporal fossa and the anterior parotid region is presented. Computed Tomography is a valuable tool for establishment of the diagnosis, before any surgical approach to the lesion is initiated and for postoperative follow-up and evaluation.