The new WHO classification of gastroenteropancreatic (GEP) neuroendocrine tumors (NET) implies that G3 neoplasms with mitotic index >20 and/or Ki67 index >20% are neuroendocrine carcinomas (NEC), described as poorly differentiated, small or large cell types, by analogy with lung NEC. To characterize the subgroup of non-small-cell-type GEP and thoracic NET with mitotic index >20 and/or Ki67 >20% according to their pathological features, response to cisplatin and overall survival (OS). We reviewed pathological and clinical presentation of G3 non-small-cell-type NET referred to our institution for 5 years. Data from 166 patients with metastatic thoracic and GEP-NET were collected. Twenty-eight patients (17%) fulfill the inclusion criteria. Tumors were classified as well-differentiated NET (G3-WDNET) in 42.8% of cases and poorly differentiated, large-cell NEC (G3-LCNEC) in 57.2% of cases. Plasma chromogranin A or neuron-specific enolase were elevated in 42 and 25% respectively of G3-WDNET and 31 and 50% of G3-LCNEC. Somatostatin receptor scintigraphy was positive in 88 and 50% of G3-WDNET or G3-LCNEC respectively. Complete or partial response to cisplatin was observed in 31% of cases, all classified as G3-LCNEC. The median OS was 41 months for G3-WDNET but 17 months for G3-LCNEC (P=0.34). Short survival was observed in 25% of G3-WDNET but 62.5% of G3-LCNEC patients (P=0.049). G3 ENETS GEP and thoracic neuroendocrine neoplasms (NEN) could constitute a heterogeneous subgroup of NEN as regards diagnosis, prognosis, and treatment. If confirmed, future classifications may consider splitting them into two groups according to their morphological differentiation.

Cyclophosphamide–dacarbazine–vincristine regimen is recommended for the treatment of malignant pheochromocytoma and paraganglioma (MPP); however, dacarbazine is the only recognized active drug in neuroendocrine tumours. We investigated the therapeutic benefit of temozolomide (TMZ), an oral alternative to dacarbazine, in patients with MPP. This is a retrospective study of consecutive patients with documented progressive MPP. We examined the correlation between Succinate dehydrogenase B (SDHB) mutation and O(6)‐methylguanine‐DNA methyltransferase (MGMT) promoter methylation and MGMT expression in the French nation‐wide independent cohort of 190 pheochromocytomas or paragangliomas (PP). Progression‐free survival (PFS) according to RECIST 1.1 and PERCIST 1.0 criteria was the primary end point. Fifteen consecutive patients with MPP were enrolled; ten (67%) carried a mutation in SDHB. The mean dose intensity of TMZ was 172 mg/m²/d for 5 days every 28 days. Median PFS was 13.3 months after a median follow‐up of 35 months. There were five partial responses (33%), seven stable (47%) and three progressive diseases (20%). Grade 3 toxicities were lymphopenia in two patients and hypertension in one. Partial responses were observed only in patients with mutation in SDHB. MGMT immunohistochemistry was negative in tumour samples from four patients who responded to treatment. SDHB germline mutation was associated with hypermethylation of the MGMT promoter and low expression of MGMT in 190 samples of the French nation‐wide independent cohort. This study demonstrates that TMZ is an effective antitumour agent in patients with SDHB‐related MPP. The silencing of MGMT expression as a consequence of MGMT promoter hypermethylation in SDHB‐mutated tumours may explain this finding.

Purpose: KEYNOTE-158 (ClinicalTrials.gov identifier: NCT02628067) investigated the efficacy and safety of pembrolizumab across multiple cancers. We present results from patients with previously treated advanced well-differentiated neuroendocrine tumors (NET). Patients and Methods: Pembrolizumab 200 mg was administered every 3 weeks for 2 years or until progression, intolerable toxicity, or physician/patient decision. Tumor imaging was performed every 9 weeks for the first year and then every 12 weeks. Endpoints included objective response rate (ORR) per RECIST v1.1 by independent central radiologic review (primary) and duration of response (DOR), progression-free survival (PFS), overall survival (OS), and safety (secondary). Results: A total of 107 patients with NETs of the lung, appendix, small intestine, colon, rectum, or pancreas were treated. Median age was 59.0 years (range, 29–80), 44.9% had ECOG performance status 1, 40.2% had received ≥3 prior therapies for advanced disease, and 15.9% had PD-L1–positive tumors (combined positive score ≥1). Median follow-up was 24.2 months (range, 0.6–33.4). ORR was 3.7% (95% CI, 1.0–9.3), with zero complete responses and four partial responses (three pancreatic and one rectal) all in patients with PD-L1–negative tumors. Median DOR was not reached, with one of four responses ongoing after ≥21 months follow-up. Median PFS was 4.1 months (95% CI, 3.5–5.4); the 6-month PFS rate was 39.3%. Median OS was 24.2 months (95% CI, 15.8–32.5). Treatment-related adverse events (AE) occurred in 75.7% of patients, 21.5% of whom had grade 3–5 AEs. Conclusions: Pembrolizumab monotherapy showed limited antitumor activity and manageable safety in patients with previously treated advanced well-differentiated NETs.

Anaplastic thyroid carcinoma (ATC) is a rare and undifferentiated form of thyroid cancer. Its prognosis is poor: the median overall survival (OS) of patients varies from 4 to 10 months after diagnosis. However, a doubling of the OS time may be possible owing to a more systematic use of molecular tests for targeted therapies and integration of fast-track dedicated care pathways for these patients in tertiary centers. The diagnostic confirmation, if needed, requires an urgent biopsy reread by an expert pathologist with additional immunohistochemical and molecular analyses. Therapeutic management, defined in multidisciplinary meetings, respecting the patient’s choice, must start within days following diagnosis. For localized disease diagnosed after primary surgical treatment, adjuvant chemo-radiotherapy is recommended. In the event of locally advanced or metastatic disease, the prognosis is very poor. Treatment should then involve chemotherapy or targeted therapy and decompressive cervical radiotherapy. Here we will review current knowledge on ATC and provide perspectives to improve the management of this deadly disease.

There is no standard for second-line chemotherapy in poorly differentiated grade 3 neuroendocrine carcinoma (G3-NEC) patients. We analyzed the antitumor efficacy of 5-fluorouracil and oxaliplatin (FOLFOX) chemotherapy in this population. A single-center retrospective analysis of consecutive G3-NEC patients treated with FOLFOX chemotherapy after failure of a cisplatinum-based regimen between December 2003 and June 2012 was performed. Progression-free survival (PFS), overall survival (OS), response rate, and safety were assessed according to RECIST 1.1 and NCI.CTC v4 criteria. Twenty consecutive patients were included (seven males and 13 females; median age 55; range 23–87 years) with a performance status of 0–1 in 75% of them. Primary location was gastroenteropancreatic in 12, thoracic in four, other in two, and unknown in two patients. There were 12 (65%) large-cell and 7 (30%) small-cell G3-NEC tumors, and 1 (5%) unknown. All patients had distant metastases. Twelve (60%) patients received FOLFOX as second-line treatment and 8 (40%) as third-line treatment or later and the median number of administered cycles was 6 (range 3–14). The median follow-up was 19 months. Median PFS was 4.5 months. Among the 17 evaluable patients, five partial responses (29%), six stable diseases (35%), and six progressive diseases (35%) were observed. Median OS was 9.9 months. Main Grade 3–4 toxicities were neutropenia (35%), thrombopenia (20%), nausea/vomiting (10%), anemia (10%), and elevated liver transaminases (10%). Our results indicate that the FOLFOX regimen could be considered as a second-line option in poorly differentiated G3-NEC patients after cisplatinum-based first-line treatment but warrant further confirmation in future larger prospective studies.