Management of neuroendocrine tumors: current and future therapies

Concomitant 177Lu-DOTATATE and Capecitabine Therapy in Patients With Advanced Neuroendocrine Tumors: A Long-term-Outcome, Toxicity, Survival, and Quality-of-Life Study

PURPOSE

The purpose of this study was to evaluate the outcome, toxicity, survival, and quality of life in patients with advanced neuroendocrine tumors.

METHODS

One hundred sixty-seven patients were enrolled in the study. All patients underwent baseline Ga-DOTANOC PET/CT scans. Lu-DOTATATE therapy was administered quarterly along with oral capecitabine therapy in group 1 patients (n = 88), whereas group 2 patients (n = 79) were treated only with Lu-DOTATATE. Hematologic, kidney function, liver function tests and chromogranin A levels were recorded before and after therapy at 2-week, 4-week, and 3-month intervals. Biochemical and morphological responses were assessed with the trend in chromogranin A levels and Response Evaluation Criteria in Solid Tumors 1.1 criteria, respectively.

RESULTS

There was no significant difference in the hemoglobin levels after Lu-DOTATATE therapy (P = 0.4892). In most patients, there was a decrease in the platelet levels; however, all the patients had platelet counts greater than 100,000/μL with no platelet toxicity. There was no toxicity related to leukocytes. Two patients showed renal insufficiencies. No hepatotoxicity was observed in any of the patients. According to Response Evaluation Criteria in Solid Tumors 1.1 criteria, in group 1 patients, the response was partial response in 34% of the patients, stable disease in 50.2%, and progressive disease in 6.8% versus partial response in 6.3%, stable disease in 60.9%, and progressive disease in 26.5% among group 2 patients. The median overall survival (OS) and progression-free survival (PFS) was not reached in group 1 patients. The median OS and PFS in group 2 patients were 48 months. Ki-67 tumor proliferation index was significantly associated with increased risk of disease progression.

CONCLUSIONS

Addition of capecitabine therapy with Lu-DOTATATE therapy lengthens the OS and PFS. Patients with aggressive disease may benefit from this synergetic therapeutic approach.

Paradigm shift in theranostics of neuroendocrine tumors: conceptual horizons of nanotechnology in nuclear medicine

We present a comprehensive review of Neuroendocrine Tumors (NET) and the current and developing imaging and therapeutic modalities for NET with emphasis on Nuclear Medicine modalities. Subsequently, nanotechnology and its emerging role in cancer management, especially NET, are discussed. The article is both educative and informative. The objective is to provide an insight into the developments made in nuclear medicine and nanotechnology towards management of NET, individually as well as combined together.

Somatostatin: One of the Rare Multifunctional Inhibitors of Mammalian Species

This review article has for major main objectives to give an overlook of the major physiological effects of somatostatin on different organs. It will cover first the general aspect of the hormone, its cDNA and its protein maturation process, as well as its characterization in various organs. This aspect will be followed by the factors involved in the control of its secretion, its intracellular mode of action, and its general action on physiological processes. Secondly, the review will focus on the pancreas, looking at its in vivo and in vitro actions with special attention on its effects on normal pancreas growth and pancreatic tumors.

A single fasting plasma 5-HIAA value correlates with 24-hour urinary 5-HIAA values and other biomarkers in midgut neuroendocrine tumors (NETs)

OBJECTIVES

5-Hydroxyindoleacetic acid (5-HIAA) is used for the evaluation of neuroendocrine tumors (NETs) but currently requires a 24-hour urine collection.

METHODS

We developed a gas chromatography mass spectroscopy-based plasma 5-HIAA assay. We compared 24-hour urine 5-HIAA values against plasma 5-HIAA values in 115 mixed-variety patients with NETs and in a subset of 72 patients with only small bowel NETs. We also compared the information gained from urinary and plasma 5-HIAA values with other biomarkers of midgut NET activity to determine the plasma assay's clinical implications.

RESULTS

In a group of 115 patients with all types of NETS, in a subset of patients with midgut NET and in a subgroup of midgut NETS with liver metastasis, the correlation between the urine and fasting plasma 5-HIAA values were statistically significant (P ≤ 0.0001). Comparison of the proportion of normal or abnormal urinary and plasma 5-HIAA values to the proportion of chromogranin, serotonin, neurokinin, or pancreastatin values that were in the normal or abnormal range yielded essentially identical information.

CONCLUSIONS

Plasma fasting 5-HIAA values are proportional to urinary 5-HIAA values and yielded identical clinical correlation with other biomarkers.