Impact of age and gender on the efficacy and safety of upfront therapy with panitumumab plus FOLFOX followed by panitumumab-based maintenance: a pre-specified subgroup analysis of the Valentino study.

BACKGROUND: The safety and efficacy outcome of elderly metastatic colorectal cancer (mCRC) patients fit enough to receive combination chemotherapy plus biological agents is an issue of growing interest. Also, gender-specific differential toxicity and efficacy of anti-epidermal growth factor receptor (EGFR)-based upfront treatments need to be explored. PATIENTS AND METHODS: Valentino was a multicenter, randomized, phase II trial, investigating two panitumumab-based maintenance strategies following first-line panitumumab plus FOLFOX in RAS wild-type mCRC patients. We carried out a subgroup analysis, aimed at assessing the differences in efficacy, safety and quality of life (QoL) according to age (<70 versus ≥70 years) and gender (male versus female). Efficacy endpoints were progression-free survival (PFS), overall survival (OS) and overall response rate (ORR); safety endpoints were rates of any grade and grade 3/4 adverse events (AEs). RESULTS: No significant differences in terms of PFS, OS and ORR were observed between patients aged <70 or ≥70 years and the effect of the maintenance treatment arm on survival outcomes was similar in the two subgroups. The safety profile of both induction and maintenance treatment and the impact on QoL were similar in elderly and younger patients. No significant differences in PFS, OS, ORR or clinical benefit rate were observed according to gender. A significantly higher rate of overall grade 3/4 AEs (P = 0.008) and of grade 3/4 thrombocytopenia (P = 0.017), any grade and grade 3/4 neutropenia (P < 0.0001) and any grade conjunctivitis (P = 0.033) was reported in female as compared to male patients. Conversely, we reported a significantly higher incidence of any grade skin rash (P = 0.0007) and hypomagnesemia (P = 0.029) in male patients. CONCLUSIONS: The upfront choice of an anti-EGFR-based doublet chemotherapy followed by a maintenance strategy represents a valuable option in RAS wild-type mCRC irrespective of gender and age, though a careful evaluation of patients to maximize the risk/benefit ratio is warranted.

Second primary neoplasms in patients with lung and gastroenteropancreatic neuroendocrine neoplasms: Data from a retrospective multi-centric study.

BACKGROUND: Patients with sporadic neuroendocrine neoplasms may exhibit a higher risk of a second primary tumor than the general population. AIM: This study aimed to analyze the occurrence of second primary malignancies. METHODS: A retrospective cohort of 2757 patients with sporadic lung and gastro-entero-pancreatic neuroendocrine neoplasms, managed at eight Italian tertiary referral Centers, was included. RESULTS: Between 2000 and 2019, a second primary malignancy was observed in 271 (9.8%) neuroendocrine neoplasms patients with 32 developing a third tumor. There were 135 (49.8%) females and the median age was 64 years. The most frequent locations of the second tumors were breast (18.8%), prostate (12.5%), colon (9.6%), blood tumors (8.5%), and lung (7.7%). The second primary tumor was synchronous in 19.2% of cases, metachronous in 43.2%, and previous in 37.6%. As concerned the neuroendocrine neoplasms, the 5- and 10-year survival rates were 87.8% and 74.4%, respectively. PFS for patients with a second primary malignancy was shorter than for patients without a second primary malignancy. Death was mainly related to neuroendocrine neoplasms. CONCLUSION: In NEN patients the prevalence of second primary malignancies was not negligible, suggesting a possible neoplastic susceptibility. Overall survival was not affected by the occurrence of a second primary malignancy.

The impact of SST2 trafficking and signaling in the treatment of pancreatic neuroendocrine tumors.

Pancreatic neuroendocrine tumors (Pan-NETs), are heterogeneous neoplasms, whose incidence and prevalence are increasing worldwide. Pan-NETs are characterized by the expression of somatostatin receptors (SSTs). In particular, SST2 is the most widely distributed SST in NETs, thus representing the main molecular target for somatostatin analogs (SSAs). SSAs are currently approved for the treatment of well-differentiated NETs, and radionuclide-labeled SSAs are used for diagnostic and treatment purposes. SSAs, by binding to SSTs, have been shown to inhibit hormone secretion and thus provide control of hypersecretion symptoms, when present, and inhibit tumor proliferation. After SSA binding to SST2, the fate of the receptor is determined by trafficking mechanisms, crucial for the response to endogenous or pharmacological ligands. Although SST2 acts mostly through G protein-dependent mechanism, receptor-ligand complex endocytosis and receptor trafficking further regulate its function. SST2 mediates the decrease of hormone secretion via a G protein-dependent mechanism, culminating with the inhibition of adenylyl cyclase and calcium channels; it also inhibits cell proliferation and increases apoptosis through the modulation of protein tyrosine phosphatases. Moreover, SST2 inhibits angiogenesis and cell migration. In this respect, the cross-talk between SST2 and its interacting proteins, including Filamin A (FLNA) and aryl hydrocarbon receptor-interacting protein (AIP), plays a crucial role for SST2 signaling and responsiveness to SSAs. This review will focus on recent studies from our and other groups that have investigated the trafficking and signaling of SST2 in Pan-NETs, in order to provide insights into the mechanisms underlying tumor responsiveness to pharmacological treatments.

A novel insight into the anticancer mechanism of metformin in pancreatic neuroendocrine tumor cells.

The antidiabetic drug metformin displays anticancer properties in several neoplasms. In pituitary NETs, aryl hydrocarbon receptor-interacting protein (AIP) is up-regulated by the somatostatin analog octreotide. Metformin inhibited QGP-1 cell proliferation in a dose- and time-dependent manner, at concentrations similar to those achievable in treated patients (-31 ± 12%, p < 0.05 vs basal at 100 µM). Moreover, metformin decreased pancreatic neuroendocrine tumors (PAN-NETs) cell proliferation (-62 ± 15%, p < 0.0001 vs basal at 10 mM), without any additive effect when combined with octreotide. Both octreotide and metformin induced AIP up-regulation. AIP silencing abolished the reduction of mTOR phosphorylation induced by metformin and octreotide. Moreover, metformin decreased HSP70, increased Zac1 and AhR expression; these effects were abolished in AIP silenced QGP-1 cells. In conclusion, metformin acts as an anticancer agent in PAN-NET cells, its activity is mediated by AIP and its interacting proteins. These findings provide a novel insight into the antitumorigenic mechanism of metformin.

The Number of Metastatic Lymph Nodes is a Useful Predictive Factor for Recurrence after Surgery for Nonmetastatic Nonfunctional Neuroendocrine Neoplasm of the Pancreas.

Nodal involvement (actually categorized as positive or negative) is an important prognostic factor after surgery for pancreatic neuroendocrine neoplasms (pNENs). We aim to evaluate the predictive role of the number of nodal metastases after pancreatic resection for pNENs. We analyzed from a prospectively maintained database all pancreatic resections for nonmetastatic nonfunctioning pNENs performed in our institution from 2011 to 2016. According to the number of nodal metastases, enhancing the actual categorization, we distinguished the following: N0, no nodal metastases; N1, 1-3 metastatic lymph nodes; and N2, metastases in 4 or more regional lymph nodes. Recurrence and disease-free survival (DFS) were evaluated. The predictive value in terms of recurrence for each clinicopathological data, including the number of metastatic lymph nodes, was calculated. Univariate and multivariate analyses were conducted. 77 patients underwent pancreatic surgery for pNENs. N0, N1, and N2 resections were found in 52 (67.5%), 16 (20.8%), and 9 (11.7%) cases, respectively. Mean follow-up of the entire cohort was 48 (±25) months. The recurrence rate was 11.8%, and the mean time of recurrence was 12 (±14) months. DFS was 83.7 months (76.0 - 91.5). At a univariate analysis, factors associated with recurrence were mitotic count (OR 1.19, p = 0.001), Ki67 value (OR 1.06, p = 0.001), the presence of nodal metastases (OR 11.54, p = 0.002), and metastases in 4 or more regional lymph nodes (N2) (OR 30.19, p = 0.002). At a multivariate analysis, only mitotic count (OR 1.51, p = 0.005) and N2 resection (OR 134.74, p = 0.002) were found to be predictive factors of recurrence. The number of metastatic lymph nodes and mitotic count is the most significant predictive factors of recurrence after pancreatic surgery for nonmetastatic nonfunctioning pNENs.

Third generation EGFR TKIs in EGFR-mutated NSCLC: Where are we now and where are we going.

The therapeutic landscape of Non Small Lung Cancer (NSCLC) has been profoundly changed over the last decade with the clinical introduction of Epidermal Growth Factor Receptor (EGFR) tyrosine kinase inhibitors (TKIs) and the discovery of EGFR activating mutations as the major predictive factor to these agents. Despite impressive clinical activity against EGFR-mutated NSCLCs, the benefit seen with 1st and 2nd generation EGFR TKIs is usually transient and virtually all patients become resistant. Several different mechanisms of acquired resistance have been reported to date, but the vast majority of patients develop a secondary exon 20 mutation in the ATP-binding site of EGFR, namely T790M. The discovery of mutant-selective EGFR TKIs that selectively inhibit EGFR-mutants, including T790M-harboring NSCLCs, while sparing EGFR wild type, provide the opportunity for overcoming the major mechanism of acquired resistance to 1st and 2nd generation EGFR TKIs, with a relatively favorable toxicity profile. The development of this novel class of EGFR inhibitors poses novel challenges in the rapidly evolving therapeutic paradigm of EGFR-mutated NSCLCs and the next few years will witness the beginning of a new era for EGFR inhibition in lung cancer. The aim of this paper is to provide a comprehensive overview of the increasing body of data emerging from the ongoing clinical trials with this promising novel therapeutic class of EGFR inhibitors.