Immunotherapeutics at the spearhead: current status in targeting neuroendocrine neoplasms.

PURPOSE: Recent advances in the field of immunotherapy have significantly prolonged the survival of patients with aggressive carcinomas, but the role of immunotherapy in neuroendocrine neoplasms (NENs) remains to be elucidated. METHODS AND RESULTS: We report a patient diagnosed with a well-differentiated grade 3 pancreatic NEN (pNEN) and type 3 liver metastases who received compassionate nivolumab as a fifth line treatment and achieved a durable partial response of more than 34 months. We have performed a systematic review to the literature on tumor microenvironment and potential biomarkers in the field of NEN including the tumor mutational burden, the tumor infiltrating lymphocytes, the programmed cell death ligand 1, and the mismatch repair system. The potential role of the immune system modulation together with a critical assessment of the recent phase II clinical studies in NEN including monotherapy with anti-PD-1/PD-L1 monoclonal antibodies, and combination therapies including anti-PD-1 along with anti-CTLA-4 monoclonal antibodies are also provided. CONCLUSION: Immunotherapeutics are gaining a post in the field of NENs in cases progressing during the course of the disease, dictating urgently the identification of biomarkers that will enable selection of NEN patients who may benefit from this treatment.

Role of Receptor Profiling for Personalized Therapy in a Patient with a Growth Hormone-Secreting Macroadenoma Resistant to First-Generation Somatostatin Analogues.

BACKGROUND: Acromegaly is almost always caused by a pituitary adenoma and is associated with high morbidity and mortality when uncontrolled. Trans-sphenoidal removal of the adenoma is the mainstay of therapy, but fails to control the disease in a significant number of patients who require further treatment. Somatostatin analogues (SSAs) as monotherapy or in combination with growth hormone (GH)-receptor antagonists and/or dopamine agonists are used either alone or in combination following surgical failure to achieve disease control. The use of specific biomarkers may help to individualize the therapeutic plan after surgical failure and direct towards a more personalized approach. METHODS: We report a 41-year-old man with acromegaly and residual disease after repeated surgery that was resistant to first-generation SSAs. RESULTS: Biochemical and tumor control were achieved following the administration of a second-generation SSA, pasireotide, combined with pegvisomant, both at maximal doses and along with cabergoline. Histology specimens showed a sparsely-granulated GH-immunostaining pituitary adenoma with intense positivity for somatostatin receptors 2 and 5 and low levels of E-cadherin. CONCLUSION: Personalized medical therapy guided by currently available biomarkers, such as immunohistochemically-characterized receptor profiling or adhesion molecules, resulted in controlled insulin-like growth factor-1 (IGF-1) and GH levels and symptom alleviation following the combination of three drug-classes.

Magnetic Resonance Imaging or Endoscopic Ultrasonography for Detection and Surveillance of Pancreatic Neuroendocrine Neoplasms in Patients with Multiple Endocrine Neoplasia Type 1?

Our aim was to compare the clinical utility of Magnetic Resonance Imaging (MRI) and Endoscopic Ultrasonography (EUS) in identifying Pancreatic Neurondocrine Neoplasms (PanNENs) and monitoring size alterations in Multiple Endocrine Neoplasia type 1 (MEN1) patients. Thirty-one MEN1 patients with PanNENs and concurrent screening by EUS and abdominal MRI were included and 129 pancreatic lesions were detected in total. MRI detected fewer lesions than EUS (n=73 vs. 110, p=0.006). MRI sensitivity and specificity compared to EUS at 20 and 10 mm cut-offs of maximal lesion diameter were 96 and 88% (20 mm cut-off) and 90 and 82%(10 mm cut-off), respectively (concordance rates of 97 and 87% and Cohen's kappa=0.912 and 0.718, respectively). Lesions<1 cm were more often detected with EUS (p=0.025). Data from sequential concurrent imaging on lesion growth rate [n=7 (mean±SD: 2 mm/year±3.4 mm vs. 1.9 mm/year±3.6 mm)] over a period of at least two years as well as pathology data in connection to preoperative concurrent imaging were available in a small number of patients (n=7, p=0.933 for mean differences in maximal lesion diameter). MRI of the pancreas was more readily available and less expensive than EUS in an outpatient setting. In conclusion, MRI performs well compared to EUS for the detection and subsequent surveillance of MEN1-related panNENs larger than 10 mm and seems to be cost-effective. Both modalities could be used at initial assessment and MRI alone could be utilized thereafter in patient surveillance. EUS retains its value in surgical planning and the detection of small mostly functional PanNENs.

Anti-tumour activity of everolimus and sunitinib in neuroendocrine neoplasms.

Comparisons between everolimus and sunitinib regarding their efficacy and safety in neuroendocrine neoplasms (NENs) are scarce. We retrospectively analysed the clinicopathological characteristics and outcomes in 92 patients with well-differentiated (WD) NEN of different origin (57 pancreatic NENs (PanNENs)), treated with molecular targeted therapy (MTT) with everolimus or sunitinib, first- (73:19) or second-line (sequential; 12:22) for progressive disease. Disease control rates (DCR: partial response or stable disease) at first-line were higher in all patients treated with everolimus than sunitinib (64/73 vs 12/19, P = 0.012). In PanNENs, DCR at first-line everolimus was 36/42 versus 9/15 with sunitinib (P = 0.062). Progression-free survival (PFS) at first-line everolimus was longer than sunitinib (31 months (95% CI: 23.1-38.9) vs 9 months (95% CI: 0-18.5); log-rank P < 0.0001) in the whole cohort and the subset of PanNENs (log-rank P < 0.0001). Median PFS at second-line MTT was 12 months with everolimus (95% CI: 4.1-19.9) vs 13 months with sunitinib (95% CI: 9.3-16.7; log-rank P = 0.951). Treatment with sunitinib (HR: 3.47; 95% CI: 1.5-8.3; P value: 0.005), KI67 >20% (HR: 6.38; 95% CI: 1.3-31.3; P = 0.022) and prior chemotherapy (HR: 2.71; 95% CI: 1.2-6.3; P = 0.021) were negative predictors for PFS at first line in multivariable and also confirmed at multi-state modelling analyses. Side effect (SE) analysis indicated events of serious toxicities (Grades 3 and 4: n = 13/85 for everolimus and n = 4/41 for sunitinib). Discontinuation rate due to SEs was 20/85 for everolimus versus 4/41 for sunitinib (P = 0.065). No additive toxicity of second-line MTT was confirmed. Based on these findings, and until reliable predictors of response become available, everolimus may be preferable to sunitinib when initiating MTT in progressive NENs.

Current concepts in the diagnosis and management of neuroendocrine neoplasms of unknown primary origin.

Neuroendocrine neoplasms (NENs) of unknown primary origin (UPO-NENs) are advanced neoplasms constituting 11-22% of all NENs that by definition their primary tissue of origin has not been identified with standard diagnostic work-up. Delineating the primary site of origin of UPO-NENs has important implications for selecting the appropriate treatment and overall prognosis. The small bowel, followed by the lung and pancreas are the most prevalent primary sites of origin of UPO-NENs that are uncovered during an extensive and prolonged diagnostic work-up; however, a number of UPO-NENs may still remain occult even after prolonged follow-up. A number of diagnostic algorithms that incorporate histopathological, molecular, imaging (either morphological or functional imaging), and serum biomarkers can help to identify the primary tumor origin. It is expected that advances in these fields will help reduce significantly the number of UPO-NENs.

The prognosis and management of neuroendocrine neoplasms-related metastatic bone disease: lessons from clinical practice.

PURPOSE: To study the evolution and optimal management of metastatic bone disease (mBD) in patients with neuroendocrine neoplasms (NENs). METHODS: Seventy-four patients were recruited from four NEN centers in this observational multicenter study. RESULTS: Pancreas and small bowel were the most common primaries (30 and 27%, respectively). Almost all gastrointestinal (GI)-NENs were grades 1 and 2, whereas bronchopulmonary-thymic were atypical carcinoids. Thirty-two (43%) patients had synchronous metastatic bone disease (mBD) and three patients reported bone-specific symptoms; metachronous mBD developed at a median of 35 (range: 4-395) months. Thirty-six (86%) of patients with metachronous mBD had stage IV disease at diagnosis. Somatostatin receptor functional imaging and computed tomography were the modalities mostly used for mBD identification. Fifty-two patients received assessable bone-related therapy (bisphosphonates, denosumab, local radiotherapy, and radionuclide treatment). Improvement in mBD was seen in 5, stable disease in 22, and deterioration in 25 patients. The presence of synchronous mBD and the negative outcome of bone-related therapy negatively affected overall survival (OS). In the multivariate analysis, the stronger predictor of OS was the outcome of bone-related therapy (HR: 4.753; 95% CI: 1.589-14.213). Bisphosphonates therapy was the mostly used bone-specific treatment but its monthly administration did not affect OS. At last follow-up, 39 patients were alive with OS 50 (14-463) months. CONCLUSIONS: Early investigation for mBD offers a prognostic marker of patients with NENs, since synchronous mBD has a negative impact on survival. The outcome of bone-related therapy affects OS but the monthly administration of bisphosphonates did not show a benefit over less intense schemes.