Radical Resection in Entero-Pancreatic Neuroendocrine Tumors: Recurrence-Free Survival Rate and Definition of a Risk Score for Recurrence.

BACKGROUND: Surgery with radical intent is the only potentially curative option for entero-pancreatic neuroendocrine tumors (EP-NETs) but many patients develop recurrence even after many years. The subset of patients at high risk of disease recurrence has not been clearly defined to date. OBJECTIVE: The aim of this retrospective study was to define, in a series of completely resected EP-NETs, the recurrence-free survival (RFS) rate and a risk score for disease recurrence. PATIENTS AND METHODS: This was a multicenter retrospective analysis of sporadic pancreatic NETs (PanNETs) or small intestine NETs (SiNETs) [G1/G2] that underwent R0/R1 surgery (years 2000-2016) with at least a 24-month follow-up. Survival analysis was performed using the Kaplan-Meier method and risk factor analysis was performed using the Cox regression model. RESULTS: Overall, 441 patients (224 PanNETs and 217 SiNETs) were included, with a median Ki67 of 2% in tumor tissue and 8.2% stage IV disease. Median RFS was 101 months (5-year rate 67.9%). The derived prognostic score defined by multivariable analysis included prognostic parameters, such as TNM stage, lymph node ratio, margin status, and grading. The score distinguished three risk categories with a significantly different RFS (p < 0.01). CONCLUSIONS: Approximately 30% of patients with EP-NETs recurred within 5 years after radical surgery. Risk factors for recurrence were disease stage, lymph node ratio, margin status, and grading. The definition of risk categories may help in selecting patients who might benefit from adjuvant treatments and more intensive follow-up programs.

Modulation of PKM alternative splicing by PTBP1 promotes gemcitabine resistance in pancreatic cancer cells.

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive and incurable disease. Poor prognosis is due to multiple reasons, including acquisition of resistance to gemcitabine, the first-line chemotherapeutic approach. Thus, there is a strong need for novel therapies, targeting more directly the molecular aberrations of this disease. We found that chronic exposure of PDAC cells to gemcitabine selected a subpopulation of cells that are drug-resistant (DR-PDAC cells). Importantly, alternative splicing (AS) of the pyruvate kinase gene (PKM) was differentially modulated in DR-PDAC cells, resulting in promotion of the cancer-related PKM2 isoform, whose high expression also correlated with shorter recurrence-free survival in PDAC patients. Switching PKM splicing by antisense oligonucleotides to favor the alternative PKM1 variant rescued sensitivity of DR-PDAC cells to gemcitabine and cisplatin, suggesting that PKM2 expression is required to withstand drug-induced genotoxic stress. Mechanistically, upregulation of the polypyrimidine-tract binding protein (PTBP1), a key modulator of PKM splicing, correlated with PKM2 expression in DR-PDAC cell lines. PTBP1 was recruited more efficiently to PKM pre-mRNA in DR- than in parental PDAC cells. Accordingly, knockdown of PTBP1 in DR-PDAC cells reduced its recruitment to the PKM pre-mRNA, promoted splicing of the PKM1 variant and abolished drug resistance. Thus, chronic exposure to gemcitabine leads to upregulation of PTBP1 and modulation of PKM AS in PDAC cells, conferring resistance to the drug. These findings point to PKM2 and PTBP1 as new potential therapeutic targets to improve response of PDAC to chemotherapy.

Endoscopic Evaluation of the Upper Gastrointestinal Tract is Worthwhile in Premenopausal Women with Iron-Deficiency Anaemia Irrespective of Menstrual Flow.

BACKGROUND: In premenopausal women, iron-deficiency anaemia is common and menstrual flow is often held responsible, but it is not clear whether these women should be submitted to gastrointestinal (GI) evaluation. We aim to prospectively investigate whether premenopausal women with iron-deficiency anaemia benefit from GI evaluation regardless of menstrual flow. METHODS: The study population comprised 59 consecutive premenopausal women with iron-deficiency anaemia. Excluded were women with obvious or suspected causes of anaemia and those ≤21 years. Heavy menstrual loss was not considered an exclusion criterion. All subjects had: complete blood count, ferritin, non-invasive testing by faecal occult blood (FOB), 13C-urea breath test (13C-UBT), anti-tissue transglutaminase antibodies (tTG) and gastrin levels. Gastroscopy with antral (n = 3), corporal (n = 3) and duodenal (n = 2) biopsies was performed in women with positive 13C-UBT or tTG titre or hypergastrinaemia. RESULTS: Heavy menstrual loss was present in 50.8%. Non-invasive tests were positive in 40/59 (67.8%): 30 had positive 13C-UBT, 12 had hypergastrinaemia, 7 had positive tTG and 3 had positive FOB. Women tested positive were similar to those tested negative as far as concerned age, haemoglobin and ferritin levels and heavy menstrual flow (55% versus 42.1%). All 40 women tested positive underwent gastroscopy with biopsies. Four (10%) had bleeding-associated lesions and 34 (85%) had non-bleeding-associated lesions. As regards upper GI findings, no differences were observed between women with normal and those with heavy menstrual flow. No lower GI tract lesions were detected in the three women with positive FOB. CONCLUSIONS: Our data suggest that premenopausal women with iron-deficiency anaemia benefit from endoscopic evaluation of the upper GI tract irrespective of menstrual flow.