Tumor carcinoide bronquial y gammagrafía de receptores de somatostatina: detección de metástasis óseas

Abstract

Surgery is the treatment of choice for bronchial carcinoid tumor (BCT), whenever the staging is adequate. There is little information about the capability of the somatostatin receptor scintigraphy (SRS) to detect bone metastases in the carcinoid tumor. This work has aimed to evaluate retrospectively the diagnostic accuracy of the SRS in the detection of bone metastases in BCT. Based on their clinical indication, the patients were classified into two different groups: Group A (n = 4), staging of a known BCT; and Group B (n = 6), treatment control. The SRS results could be correlated with the CT results in all 4 patients from the group A, and in one patient from the group B, and the SRS results were compared with the clinical follow up during at least one year in the other 5 patients. The SRS scan detected the 4 BCT from the group A; in 2 of them the patient staging was superior when the SRS was used than with the CT, whereas the scan overestimated the tumor stage (BCT + sarcoidosis) in another patient. During the clinical course, one of these patients developed bone and liver metastases. The SRS was normal in 5 asymptomatic patients from group B, whereas the scan showed disseminated metastatic disease (liver, bone, spleen and lymph nodes) in another patient. In the 2 patients with bone metastases, the total number of bone metastases detected by the bone scan was 12, and by the SRS 8. The four lesions that were not detected by SRS were located in the ribs (n = 3) and 12-D (n = 1). The capability of the SRS to detect bone metastases makes it more useful in BCT staging. Over the next few years, the role of the bone scan and SRS in the detection of bone metastases in carcinoid tumors needs to be established.