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Secondo Lastoria

Publications and source records attributed to Secondo Lastoria.

5 recordsLinked to original sources

Somatostatin analogs and prednisone in advanced refractory thymic tumors.

BACKGROUND: Therapeutic options to cure advanced, recurrent, and metastatic thymic tumors are limited. Evidence of a high uptake of indium-labeled octreotide ((111)In-DTPA-D-Phe(1)-octreotide) in thymic tumors and the curative application of somatostatin analogs and prednisone in one patient with thymoma and pure red cell aplasia led the authors to start a Phase II study. METHODS: Sixteen patients with advanced thymic tumors, unresponsive to conventional chemotherapeutic regimens, were enrolled in the study. The schedule includes administration of somatostatin analog octreotide (1.5 mg/day subcutaneously) associated with prednisone (0.6 mg/kg/day orally for 3 months, 0.2 mg/kg/day orally during follow-up). In 8 cases, octreotide was replaced by the long-acting analog lanreotide (30 mg/every 14 days intramuscolarly). Treatment was prolonged until progression of disease was documented. Overall response rate, survival, progression free survival, and toxicity were evaluated. RESULTS: The overall response rate among 16 evaluable patients was 37%. One patient (6%) had a complete response, 5 (31%) had a partial response, 6 obtained a stabilization of disease, and 4 progressed during the treatment. After a median follow-up of 43 months, the median survival was 15 months, and median time to progression was 14 months. Treatment was generally well tolerated with acceptable toxicity: cholelithiasis (1 patient), Grade 2 cushingoid appearance (3 patients), Grade 1 diarrhea (5 patients), Grade 2 hyperglycemia (3 patients). CONCLUSIONS: Treatment with somatostatin analogs and prednisone has shown efficacy in patients with recurrent and metastatic malignant thymic tumors refractory to standard therapeutic options. The results obtained are very satisfactory given the lack of effective alternative treatments. Such therapy is not burdened by the same toxicity of chemotherapy; thus, it can be administered to heavily pretreated patients. Somatostatin analogs and prednisone are well tolerated, and the long-acting analog lanreotide, which requires fewer injections, improves patients' compliance.

Administration, Oral↗

Functional imaging of Langerhans cell histiocytosis by (111)In-DTPA-D-Phe(1)-octreotide scintigraphy.

BACKGROUND: Langerhans cell histiocytosis is a rare group of diseases of unknown pathogenesis, variable clinical presentation, and behavior. It encompasses highly aggressive, often fatal, and indolent diseases, with a variety of intermediate forms between the two extremes. Localization and monitoring of Langerhans cell histiocytosis deposits are based on the combined use of different imaging modalities, which include magnetic resonance, computed tomography, and nuclear medicine procedures. Somatostatin receptor scintigraphy recently has been used to image immune-mediated diseases with excellent results. METHODS: In this study, the authors have evaluated the potential role of somatostatin receptor scintigraphy by using (111)In-DTPA-D-Phe(1)-octreotide in a series of patients with Langerhans cell histiocytosis. Eight consecutive patients (2 males, 6 females; mean age, 43 years; age range, 29-60 years) with histologically proven Langerhans cell histiocytosis, in various phases of their disease, were imaged 24 hours after intravenous injection of 111-222 MBq of (111)In-DTPA-D-Phe(1)-octreotide, by using total body and spot view images. The objective of the study was to preliminarily evaluate this technique in the evaluation of Langerhans cell histiocytosis. RESULTS: Most Langerhans cell histiocytosis deposits were clearly documented by somatostatin receptor scintigraphy, independently from the anatomic location (i.e., skeleton, mucosae, soft tissue, etc.). The correlation between conventional imaging modalities and somatostatin receptor scintigraphy results was fairly good, though this was not considered a primary objective of the study. CONCLUSIONS: Among the various imaging modalities for Langerhans cell histiocytosis, somatostatin receptor scintigraphy is unique, because it accurately depicts the active sites of disease and thus can help in monitoring the response to treatment, together with conventional imaging modalities. Further studies are necessary to confirm the diagnostic value of this technique and clarify the biologic significance of the expression of somatostatin receptors in Langerhans cell histiocytosis.

Adult↗

(99m)Technetium pentavalent dimercaptosuccinic acid scintigraphy in the follow-up of clinically nonfunctioning pituitary adenomas after radiotherapy.

BACKGROUND: It is still difficult to differentiate pituitary adenoma remnants from postradiotherapy fibrosis by computed tomography (CT) or magnetic resonance imaging (MRI), especially in patients with clinically nonfunctioning pituitary adenomas (NFA), lacking circulating markers to follow disease progression or cure. OBJECTIVE: We investigated the usefulness of scintigraphy with technetium-99m pentavalent dimercaptosuccinic acid [(99m)Tc(V)DMSA], shown previously to detect most pituitary GH- and PRL-secreting adenomas and NFA, with tumour-to-background ratios (T/B) as high as 25-fold. PATIENTS: Eighteen patients with NFA (study group), 10 patients with GH- and three patients with PRL-secreting adenomas (control group), all of whom had undergone previous surgery. DESIGN: The study was an open longitudinal design. Pituitary CT/MRI and (99m)Tc(V)DMSA scintigraphy was performed before and 1, 3 and 5 years after conventional radiotherapy. Tumour size was measured as maximal diameter of the residual lesion, while uptake of (99m)Tc(V)DMSA was measured as a T/B ratio. RESULTS: At study entry, pituitary (99m)Tc(V)DMSA uptake was found in 13 NFA (72.2%), seven GH-secreting (70%) and all PRL-secreting adenomas; remnant tumour was documented by CT/MRI in all 31 patients. Maximal remnant diameter was significantly higher in patients with positive (13.3 +/- 0.9 mm) than in those with negative scintigraphy (7.0 +/- 0.3 mm, P < 0.001). During the 5-year follow-up postradiotherapy, a significant decrease in (99m)Tc(V)DMSA uptake (9.7 +/- 0.8 vs. 3.2 +/- 0.5, P < 0.0001) occurred in all but three patients. Two NFA patients died of tumour invasion 19 and 36 months after radiotherapy and one acromegalic patient had no change in his hormone levels. In the eight negative patients (five NFA and three GH), scintigraphy remained negative throughout follow-up. A remarkable shrinkage of the remnant tumour was observed in both the patients with negative (from 7.0 +/- 0.3 to 1.9 +/- 0.6 mm, P < 0.001) and in those with positive scintigraphy (from 13.3 +/- 0.9 to 7.3 +/- 0.6 mm, P < 0.001). At the end of the study, CT/MRI showed evident remnant tumour in 13 of 16 NFA (81.2%), nine GH-secreting (90%) and all three prolactinomas (100%), while the scintigraphy was negative (T/B < 1) or faintly positive (T/B 1-2) in eight of 16 NFA (50%), five GH-secreting (50%) and one prolactinoma (33.3%). CONCLUSIONS: Functional imaging of pituitary remnant adenomas (> 10 mm in size) by (99m)Tc(V)DMSA depicts viable pituitary adenoma remnants. This approach may be of clinical value in patients with clinically nonfunctioning adenomas to monitor the effects of radiotherapy.

Adenoma↗

In vitro and in vivo expression of somatostatin receptors in intermediate and malignant soft tissue tumors.

BACKGROUND: Previous studies showed that the subtype 2 of somatostatin receptors (sstr2) is generally expressed by soft tissue sarcomas. MATERIALS AND METHODS: Using reverse transcription-polymerase chain reaction (RT-PCR), the present study evaluated the expression of sstr mRNA in 31 human intermediate and malignant soft tissue tumors. In 8 patients somatostatin receptor scintigraphy was performed to detect soft tissue tumor sites and visualize in vivo sstr expression. RESULTS: Somatostatin receptors were identified in 84% of the tumors analyzed by RT-PCR analysis. sstr1 and sstr2 were the receptors most frequently detected. Somatostatin receptor scintigraphy was able to identify primary and/or metastatic sites in 7 out of 8 patients, with an overall sensitivity per site of 87%. Concordant results were found between in vitro and in vivo techniques. CONCLUSION: The wide expression of sstrs in soft tissue tumors suggest a relevant role for these receptors in diagnosis and may have therapeutic applications.

Adult↗