Pii: S1010-7940(02)00109-4

We read with interest the paper by Dell’Asta et al. [1]. In 1995 we published an article in which we pointed out the importance of In-DTPA-Pentetreotide scintigraphy (Octreoscan) in the preoperative diagnosis of ACTH-producing bronchial carcinoid [2]. Neuroendocrine tumors (of which spectrum bronchial carcinoid are comprised [3]) of the lung and the thymus are most frequently responsible for ectopic ACTH-producing tumors. They express tissue receptors for somatostatin (sst1–sst5 subtype receptors) well detected by polymerase chain reaction (PCR) technique. The current generation of somatostatin analogs (octreotide, lanreotide) binds with high affinity to sst2 receptor subtype, with lower affinity to sst3 and sst5, and do not bind sst1 and sst4 [4]. In vivo expression of sst2 receptors is provided by Octreoscan: thus tumors expressing high quantity of these receptors became a potential target for octreotide or lanreotide. Octreoscan is effective in diagnosing neuroendocrine tumors of the lung (and of the thymus), their eventual metastases to mediastinal lymph nodes and their local or distant recurrences. Distant metastases or recurrences are often discovered in the absence of symptoms with higher accuracy than traditional radiological procedures [5]. We have recorded a recurrence of a radically resected ACTH-producing typical bronchial carcinoid in the mediastinum, promptly discovered by Octreoscan. The patient decided not to be submitted to re-intervention, and he received medical therapy with octreotide, with a good control of the symptoms. Positive Octreoscan can, in fact, influence a medical therapy with octreotide or lanreotide, in case of metastatic neuroendocrine tumors [5]. For example, with prolonged circulating half-life and non-toxic sideeffects octreotide is an excellent somatostatin analog for medical application. Recently, radiometabolic treatment with octreotide was proposed in patients with metastatic neuroendocrine tumors: this procedure can be used in selected cases in which surgery is not feasible. Surgery remains, in fact, the treatment of choice in these patients, but not always possible. We agree with the authors [1] in their diagnostic protocol for neuroendocrine ACTH-producing tumors, and we emphasize the utility of Octreoscan in the preoperative study and follow-up for all neuroendocrine neoplasm of the chest.