The SUNEVO (GETNE-1408) trial to evaluate the activity and safety of thecombination of sunitinib with evofosfamide (TH-302) in patients with G1/G2 metastatic pancreatic neuroendocrine tumours (pNETs) naïve forsystemic treatment: A phase II study of the Spanish Task Force Group for Neuroendocrine and Endocrine Tumors (GETNE)

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Background: Angiogenesis plays an important role in tumorigenesis and progression of pNETs. Evofosfamide (EVO) is a DNA alkylator prodrug that selectively activates under hypoxia. Sunitinib as monotherapy shows a wide range of responses (9-24%) in similar populations. We hypothesized that sunitinib-induced hypoxia might increase the cytotoxic activity of EVO in patients with metastatic pNETS and naïve for systemic treatment other than somatostatin analogues (SSA). Methods: This is a phase-II, single-arm, and multicenter trial of EVO (340mg/m2 on days 8, 15 and 22 every 4 weeks) and sunitinib (37.5mg/day continuously). Primary endpoint was Objective Response Rate (ORR) by RECIST v1.1 assessed every 8 weeks. A Simon two-stage optimal design was used, considering a minimum of 3 responses in the first 18 pts in order to start with the second stage (power = 0.80, alpha = 0.05). Results: Between May/2015 and May/2018, 17 pts were included (median age was 62.4 y.o). Prior SSA was reported in 7 (41.2%) pts and 8 (47.1%) had a Ki-67 > 10%. There were 2 responders (11.8%; n = 1 complete and n = 1 partial response); stable disease was observed in 76.5%. Median (range) PFS and duration of response were 10.4 months (m) (2.9-17.9m) and, respectively 24.4m (13.7-35.2m), respectively. Grade 3 or 4 adverse events occurred in 11 (64.7%) pts, being neutropenia (33.3%), fatigue (16.7%), thrombocytopenia (11.1%), hand-foot syndrome (5.6%), and pancreatitis (5.6%) the most frequent. Toxicity led to treatment discontinuation in 5 (38.5%) pts. Dose reductions were reported in 20% (sunitinib) and 100 % (EVO) of pts. Conclusions: Combination of sunitinib and EVO failed to demonstrate activity in terms of tumor shrinkage as only two patients achieved response, therefore, second stage was not proceeded. While cross trial comparisons are difficult, response rate of 12% with the combination was disappointing. Concerns over toxicity arose; translational analysis are undergoing. Clinical trial information: NCT02402062.

Impact of gender on multikinase inhibitors (MKIs) toxicity in patients (pts) with advanced pancreatic and gastrointestinal neuroendocrine tumors (NETs): A pooled analysis of two phase II trials with pazopanib and lenvatinib

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Background: Retrospective data in some cancer types suggested a possible different toxicity profile with chemotherapy and targeted therapies according to gender. However, data from prospective studies are still very limited, especially in infrequent tumors such as NETs. Methods: Pts with advanced pancreatic and gastrointestinal NETs treated with pazopanib or lenvatinib in the multicenter open-label phase II studies PAZONET and TALENT respectively, were included in the analysis. Both studies were performed by Spanish Task Force Group for Neuroendocrine Tumors (GETNE). All toxicity grades with an incidence higher than 5% were considered for univariate review. Additionally, all grade 3-4 toxicities were analyzed separately. Results: 155 pts (47.7% female) with 1213 adverse events (AEs) (20% G3-4) divided in 121 categories were included. In female patients, liver toxicity, headache, pyrexia, nausea/vomiting, hair/skin disorders and dizziness were significantly more common (table). The only toxicity with higher incidence in men was dysphonia (OR 0.42, 95% CI 0.2-0.9, p 0.02). There were no gender differences in grade 3-4 toxicities. Conclusions: We observed significant differences in toxicity AEs by gender in two prospective phase II studies with MKIs in NETs patients. Potential different approach to manage toxicity may be adopted based on gender. [Table: see text]

Final results of the TALENT trial (GETNE1509): a prospective multicohort phase II study of lenvatinib in patients (pts) with G1/G2 advanced pancreatic (panNETs) and gastrointestinal (giNETs) neuroendocrine tumors (NETs)

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Background: Approved systemic therapies for advanced NETs have showed limited tumor shrinkage and no data of activity after progression to prior targeted agents (TA) is available. Lenvatinib, a potent VEGFR1-3 & FGFR1-4 inhibitor may increase efficacy and revert primary and acquired resistance to TA. We report the final results of the TALENT trial. Methods: Two independent cohorts were included: panNETs and giNETs. All pts had baseline documented progression disease (PD) by RECIST. For panNETs, PD to TA was mandatory, regardless of prior therapy with somatostatin analogs (SSAs) or chemotherapy (CHT); and for giNETs, PD on SSAs. Pts were treated with lenvatinib at 24 mg qd until PD or intolerable toxicity. The primary endpoint was overall response rate (ORR) by central radiology review. Progression-free (PFS) and overall survival (OS) were assessed by investigator. With 55 pts per arm, our study was powered to identify an ORR ≥25% (90% power, 5% α-error). Results: We recruited 111 pts: 55 panNETs and 56 giNETs (78% from small intestine). Prior therapies were CHT 32%, SSAs 87%, everolimus 70% and sunitinib 30% for panNETs. ORR was 29%, 42.3% for panNETs and 16.3% for giNETs. With a median follow-up of 19 m, PFS and OS for panNETs were 15.5 m (95% CI 11.3-not reached (NR)) and 29.2 m (95% CI 23.2-NR); and 15.4 m (95% CI 11.5-19.4) and NR for giNETs, respectively. Pts who obtained a response by RECIST had a significantly better PFS compared with non-responders (NR vs 11.2 m in panNETs (p=0.004); 37.2 m vs 14.9 m in giNETs (p=0.005). In the subgroup analyses, all pts obtained the same benefit in PFS and ORR, including tumor grade, prior therapies, hormone release, primary location and tumor burden. The most frequent G3/4 adverse events were hypertension (22%), fatigue (11%) and diarrhea (11%). Dose reductions/interruptions were needed in 91.8% with a median dose of 20 mg qd. Conclusions: To our knowledge, we report the highest ORR by central radiology assessment with a TA in this setting. Lenvatinib showed a promising PFS and OS in a pretreated population with benefit across subgroups. Further development in advanced NETs is warranted. Clinical trial information: NCT02678780.

Molecular profile of ampulla of vater carcinoma (AVC): A rare tumor type with meaningful molecular alterations

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Background: AVC is a rare type of cancer with dismal prognosis and limited therapeutic options due to the lack of specific clinical trials. Two histologic subtypes predominate, namely pancreatobiliary and intestinal. A variety of molecular alterations have been described in AVC, but their clinical and therapeutic implications have not been studied in detail. Methods: Retrospective cohort study of patients (pts) diagnosed with AVC treated in our institution from 2010 to 2018. We routinely performed Next Generation Sequencing in all AVC tumors. Our main objectives were to describe the molecular profile of AVC and correlate with clinical outcomes. Results: Out of 26 pts with AVC, 13 pts were male (50%), median age 65 (range 43-83), 7 pts (27%) had stage IV disease at diagnosis. Histologic type was pancreatobiliary in 18 pts (69%), intestinal in 7 pts (27%) and mixed in one case (4%). We identified KRAS mutations (mut) in 10 pts (7 pancreatobiliary, 2 intestinal, 1 mixed), TP53 mut in 6 pts (4/1/1), PIK3CA mut in 3 pts (3/0/0), ERBB2 mut in 3 pts (2/1/0), CTNNB1 mut in 3 pts (2/1/0). In pancreatobiliary we found single cases with RNF43, BRCA1 and CHEK2 mut; while in intestinal we found single cases with NRAS and BRAF mut. One tumor of intestinal subtype had microsatellite instability (MSI). Three pts were included in phase I clinical trials, 2 of them with trials based on tumor profile (ERBB2 mut with pan-HER inhibitor and MSI with immunotherapy). Median overall survival (OS) was 21 months for pts with stage I, II and III disease (95% CI 12.37-not reached) and 13.2 months for stage IV disease at diagnosis (95% CI 5.73-not reached). In cox models, median OS was not dependent on KRAS or TP53 mutation status, or histological subtypes. Conclusions: AVC is a rare type of cancer with two differentiated histological subtypes harboring unique molecular alterations that can be matched to investigational therapies. A broader knowledge of the biology of these tumors is needed to improve patient outcomes.

The Role of Fluoropirimidines in Gastrointestinal Tumours: from the Bench to the Bed

PURPOSE

Gastrointestinal tumours are one of the most common types of cancer. Therapeutic options include surgery, radiotherapy, local ablation techniques, targeted agents, and chemotherapy. Fluoroprimidines are one of the most active drug families in digestive tumours and remains the cornerstone of the most commonly used chemotherapy schemes.

METHODS

We review the molecular basis of thymidylate synthase inhibition and the mechanisms of action of 5-fluorouracil, next generation oral fluoropyrimidines (capecitabine, tegafur and the latest S-1 and TAS-102) and antifolates.

RESULTS

In addition, mechanisms and biomarkers of resistance and toxicity are explored. Finally, new fluoropyrimidines development and clinical trials ongoing in digestive tumours are reviewed.

CONCLUSIONS

Further research is necessary to avoid resistance mechanisms, improve clinical outcomes and continue reducing toxicities. Until new drugs become available, the optimization of current therapies should be a priority.

Prognostic models in advanced gastric cancer in first and second line chemotherapy treatment in Spanish population

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Background: No globally accepted prognostic score has been developed in advanced gastric cancer (AGC). The purpose of this study is to explore baseline host or tumor related prognostic factors in spanish AGC patients in first and second line chemotherapy treatment. In addition we compare our scores with previously published scores in asian and european population. Methods: A total of 166 patients with AGC treated in our institution between 2012 and 2016 were screened. 119 received first line chemotherapy (CT) and 47 of them also received second line CT and were included in the analysis. Prognostic factors were evaluated using the Cox proportional hazard model. We use as comparators four first line and three second line scores published in literature. Results: The overal survival (OS) in first line and second line patients were 9 and 5 months. To construct first line CT score we selected four risk factors: ECOG≥2, Her2 negative, Irinotecan based CT and albumin < 3,6mg/dl. OS were 23 months in low risk group, who had zero or one risk points, 15 months for patients in the moderate risk group, who had two or three risk points, and 5 months for patients in the high risk group, who had all four risk points. In the second line CT score we included four risk factors: ECOG ≥2, albumin < 3.6mg/dl, Hb < 11.5mg/dl and CA19.9 reduction less than 30% after 2 CT cycles. OS were 30 months in low risk group, who had zero or one risk points, 16 months for patients in the moderate risk group, who had two or three risk points, and 3 months for patients in the high risk group, who had all four risk points. Conclusions: In the present study, we propose two new prognostic scores for patients with AGC developed in the same cohort and including HER2 status. This prognostic model could help clinicians choose and applicable treatment based on the stimated prognosis. [Table: see text]

Metastatic extraskeletal Ewing's sarcoma treated with trabectedin: A case report

The Ewing's sarcoma family of tumors (ESFT) comprises a number of rare malignant tumors. Standard first-line treatment for patients with these tumors includes chemotherapy with a five-drug regimen of vincristine, doxorubicin (Adriamycin^®) and cyclophosphamide, alternating with ifosfamide and etoposide (VAC/IE). In cases of inadequate response, there are a number of second-line regimens available. However, further treatment options are required for those patients with disease unresponsive to standard treatment. Trabectedin is a novel treatment option for patients with ESFT. The present study reports the case of a Caucasian 69-year-old female patient who presented with a soft tissue mass on the chest wall that had developed 7 months earlier. A computed tomography scan revealed a 9×8×7-cm mass on the anterior chest wall above the pectoral muscle. Histopathological evaluations and molecular analysis indicated that it was consistent with a metastatic extraskeletal Ewing's sarcoma. The patient was treated with an alternating VAC/IE regimen; however, an inadequate response was observed. The patient received second-line treatment with a gemcitabine and dacarbazine combination regimen, but the disease progressed. Subsequently, treatment with trabectedin (1.5 mg/m² as a 24-h continuous infusion every 3 weeks) was initiated. Trabectedin treatment resulted in long-lasting (18 months) progression-free survival. It is vital that novel drugs continue to being developed for patients with ESFT following progression subsequent to standard chemotherapy. The current report presents a case of a patient with metastatic, pre-treated Ewing's sarcoma achieving disease stabilization with trabectedin. Based on these results and the observed tolerability profile, trabectedin represents an alternative treatment for patients with ESFT. Further studies are required in order to determine the efficacy of trabectedin as monotherapy or in combination with other drugs. It is also important to identify which tumor subtypes, specific translocations and patient profiles will benefit the most from treatment with trabectedin.

Brain metastasis in basaloid undifferentiated anal carcinoma: A case report

Anal cancer is a rare tumor that accounts for 2% of all colorectal neoplasms. The brain is a rarely affected organ. The aim of the present study was to the review the only four cases of anal cancer brain metastases previously published in the literature. In addition, the current study presents the case of a 69-year-old male diagnosed with basaloid undifferentiated carcinoma of the anal canal (stage IV with liver, lung and bone metastasis). Despite the patient’s good response to chemotherapy and the achievement of a partial response that was maintained for 14 months, brain metastases developed. Although radiotherapy was administered, the patient succumbed to the condition 12 weeks after the diagnosis of brain metastasis.