Evaluation of response on treatment patients with progressive metastatic NETs using 90Y DOTA TATE

Abstract

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Objectives: The aim of this study was present our results of treatment patients with NET using 90Y DOTA TATEusing RECIST guidelines.

Methods: The case records of 19 patients (age range 23–72 years, mean 52 years old, everyone with histological diagnosis neuroendocrine carcinoma, 15 cases of GEP-NET (NECLM), midgut carcinoid (9pts and foregut tumour – pancreas 6pts. Additional 2pts had atypical bronchial carcinoid, next 2pts had malignant pheochromocytoma. All received 90Y DOTA TATE. An average overall dose was 14,8GBq (3.2-3,9GBq/treatment). Every patient had 3 or 4 therapy session and 6 weeks intervals. In each case response was assessed with cross sectional imaging (spiral CT), biochemical profile and evaluation of clinical symptoms. Next day post-therapeutic planar WB images using “Bremsstrahlung” were acquired.

Results: Overall 65 therapies using 90Y DOTA TATE were given over 12m without significant toxicity and side effects after treatment. Mean clinical follow-up was 4,1 months. Consider RECIST guidelines of objective response there were 5 patients (26%) with partial response (PR), 11 patients (58%) with disease stability (DS) and 3 patients (16%) had disease progression (DP). Those with PR there were 2 patients with midgut and 3 foregut tumour. In those with DS, 6 had midgut NECLM and 4 had forgut tumour, single patient had malignant pheochromocytoma. Biochemical response significant drop of CgA was noted in 8 patients (42%), 4 had midgut tumours, next 4 foregut, single case of non-secretory malignant pheochromocytoma had decrease level of VMA. In those patients with increase of CgA 3 of them had midgut and next 3 patients had foregut tumour. Clinical response was noted in 12 patients (63%) in terms of general physical examination and signs and symptoms of disease. Patients with clinical response, 6 had midgut tumour and 5 had foregut tumour, single had malignant pheochromocytoma. Disease stability with no change of clinical symptoms was noted in 6 patients (32%), 3 had midgut and other 3 hat foregut tumour. Only single patient with malignant pheochromocytoma had evidence of clinical progression with worsening of pain due to evidence of progression seen in CT

Conclusions: Therapy using 90Y DOTA TATE was without significant toxicity and side effects after treatment. Objective response on treatment using RECIST was similar as previous reports using 90Y DOTA TOC. Clinical response was better then objective response.