Temozolomide-based combination for advanced neuroendocrine neoplasms: a systematic review of the literature

Observational Study on Antibody Response to COVID-19 Vaccines in PAtients with Gastro-Entero-PanCreatic Cancers and NeuroendocrIne NeoplAsms on Systemic TreatmEnts (VACCINATE)

The coronavirus disease-19 (COVID-19) pandemic dramatically impacted oncological patients' care. Since the introduction of vaccines and the demonstration of their benefit on frail patients, COVID-19 vaccinations were indicated to also be beneficial to oncological population. However, data about the impact of anticancer-treatments and the timing between vaccinations and systemic therapy delivery were not available. We aimed to evaluate potential factors influencing the outcome of the COVID-19 vaccination in cancer patients. We prospectively collected data of patients undergoing the COVID-19 vaccination with gastro-entero-pancreatic and neuroendocrine neoplasms, treated at our institute, between 03/2021 and 12/2021. We enrolled 46 patients, 63.1% males; at the time of data collection, 86.9% had received two-doses of Pfizer-BioNTech and the rest had received the Moderna vaccine. All patients obtained a subsequent immune-response. Chemotherapy seems to determinate a significantly lower antibody response after vaccination compared to the other anti-cancer agents (p = 0.004). No significant effect on immune-response was reported for both vaccinations performed ≤7 vs. >7 days from the last systemic treatment (p = 0.77) and lymphocytes count (p = 0.11). The findings suggest that the optimal timing for COVID-19 vaccination and lymphocytes count are not the issue, but rather that the quality of the subset of lymphocytes before the vaccination determine the efficacy level of immune-response in this population.

Capecitabine and Temozolomide (CAPTEM) in Advanced Neuroendocrine Neoplasms (NENs): A Systematic Review and Pooled Analysis

Background

Retrospective studies and single center experiences suggest a role of capecitabine combined with temozolomide (CAPTEM) in neuroendocrine tumors (NENs).

Methods

We performed a systematic review to assess the efficacy and safety of CAPTEM in patients affected with NENs, with the aim to better clarify the role of this regimen in the therapeutic algorithm of NENs.

Results

A total of 42 articles and 1818 patients were included in our review. The overall disease control rate was 77% (range 43.5%-100%). The median progression free survival ranged from 4 to 38.5 months, while the median overall survival ranged from 8 to 103 months. Safety analysis showed an occurrence of G3-G4 toxicities in 16.4% of the entire population. The most common toxicities were hematological (27.2%), gastrointestinal (8.3%,) and cutaneous (3.2%).

Conclusion

This systematic review demonstrated that CAPTEM was an effective and relatively safe treatment for patients with advanced well-moderate differentiated NENs of gastroenteropancreatic, lung and unknown origin.

The optimal duration of capecitabine plus temozolomide in patients with well-differentiated pancreatic NETs with or without maintenance therapy

BACKGROUND

The optimal duration of capecitabine combined with temozolomide (CapTem) for metastatic pancreatic neuroendocrine tumours (PanNETs) remains controversial. The present study aimed to assess the activity and safety of prolonged CapTem and Cap maintenance therapy in patients with metastatic PanNETs.

METHODS

Retrospective real-world data of 94 patients with metastatic PanNETs were obtained from one cancer centre. Fifteen patients were treated with Cap maintenance therapy after fixed 12-13 cycles of CapTem (group I), 44 patients were treated with prolonged CapTem until disease progression (group II), and 35 patients were treated with fixed 12-13 cycles of CapTem (group III).

RESULTS

The mean ± SE follow-up period was 41.79 ± 26.31 months. The median CapTem treatment duration was 12 months in group I and 14 months in group II. The median time to best partial response was 12 months both in groups I and group II. The objective response rates of groups I and II were significantly higher than those of group III (73.3%, 41.9%, and 20%, respectively, p = .002). The median progression-free survival (mPFS) of group I and group II was significantly higher than that of group III (35 months, 26 months vs. 19 months, p < .001). Safety analysis of the three groups indicated rare events of grade 3-4 toxicities, with nausea, vomiting, fatigue, and anaemia being the most common adverse effects.

CONCLUSIONS

Patients with PanNETs who responded well to CapTem treatment may benefit from prolonged CapTem and Cap maintenance therapy after fixed cycles. Prospective studies are encouraged to further explore the prolonged CapTem treatment and maintenance therapy.

Rational Multitargeted Drug Design Strategy from the Perspective of a Medicinal Chemist

The development of multitarget-directed ligands (MTDLs) has become a widely focused research topic, but rational design remains as an enormous challenge. This paper reviews and discusses the design strategy of incorporating the second activity into an existing single-active ligand. If the binding sites of both targets share similar endogenous substrates, MTDLs can be designed by merging two lead compounds with similar functional groups. If the binding sites are large or adjacent to the solution, two key pharmacophores can be fused directly. If the binding regions are small and deep inside the proteins, the linked-pharmacophore strategy might be the only way. The added pharmacophores of second targets should not affect the binding mode of the original ones. Moreover, the inhibitory activities of the two targets need to be adjusted to achieve an optimal ratio.

Combination of PARP inhibitor and temozolomide to suppress chordoma progression

Chordoma, a malignant bone cancer, is highly resistant to conventional therapeutic approaches; this greatly limits radio- and chemotherapeutic options and disease management. In the present study, we investigated three patient-derived chordoma cell lines to elucidate the molecular mechanism of resistance to therapeutics. An in vitro high-throughput chemical screening assay and an in vivo xenograft model were used to identify novel chemosensitizers for chordoma. We found that patient-derived chordoma cell lines recapitulated disease phenotypes, which were highlighted by robust resistance to medical therapy manifested as lack of DNA damage accumulation. Mechanistically, the PARP DNA repair pathway was found to play a central role in this resistance. Chemical screening confirmed that PARP inhibitors could strikingly enhance temozolomide (TMZ) therapy in chordoma cells. Combining the FDA-approved PARP inhibitor, olaparib, with chemotherapeutics not only potentiated DNA damage accumulation, cell cycle arrest, and apoptosis in vitro but also suppressed chordoma xenograft expansion in vivo. We conclude that combining PARP inhibition with TMZ could be an effective therapeutic approach for the clinical management of chordoma. KEY MESSAGES: The PARP DNA repair pathway enhances chemoresistance in chordoma cells. Combining PARP inhibitors with genotoxic agents induces chordoma cell cytotoxicity. PARP inhibitor combining with temozolomide suppresses growth of chordoma in vivo.

Activity and Safety of Standard and Prolonged Capecitabine/Temozolomide Administration in Patients with Advanced Neuroendocrine Neoplasms

BACKGROUND

Capecitabine and temozolomide combination (CAPTEM) is associated with high response rates in patients with advanced neuroendocrine neoplasms (NENs). We evaluated the real-world activity and safety of CAPTEM from 3 NEN centers.

METHODS

Clinicopathological characteristics and outcomes of patients treated with CAPTEM for bulky or progressive disease (PD) were retrospectively analyzed. -Results: Seventy-nine patients with gastroenteropancreatic (grades 1-2 [n = 38], grade 3 [n = 24]) and lung/thymic (n = 17) NENs were included. Median treatment duration was 12.1 months (range 0.6-55.6). Overall, partial responses (PRs) occurred in 23 (29.1%), stable (SD) in 24 (30.4%), and PD in 28 (35.4%) patients. Median progression-free survival (PFS) and overall survival (OS) were 10.1 (6-14.2) and 102.9 months (43.3-162.5), respectively. On univariate analysis, NENs naive to chemotherapy and low Ki67 were associated with favorable responses (partial response [PR] + SD; p = 0.011 and 0.045), PFS (p < 0.0001 and 0.002) and OS (p = 0.005 and 0.001). Primary site (pancreas and lung/thymus) was also a significant prognostic factor for PFS (p < 0.0001) and OS (p < 0.0001). On multivariate analysis, gastrointestinal and unknown primary NENs (hazard ratio [HR] 0.3, 95% CI 0.1-0.8, p = 0.009 and p = 0.018) and prior surgery (HR 2.4, 95% CI 11-4.9, p = 0.021) were independent prognostic factors for PFS. Ki-67 was a poor predictor for favorable response in receiver operating characteristic analysis (area under the curve 0.678). Safety analysis of CAPTEM indicated rare events of serious (grades 3-4) toxicities (n = 4) and low discontinuation rates (n = 8) even in patients with prolonged administration (>12 months).

CONCLUSIONS

CAPTEM treatment can be an effective and safe treatment even after prolonged administration for patients with NENs of various sites and Ki67 labeling index, associated with significant favorable responses and PFS.

Safety and efficacy of combining capecitabine and temozolomide (CAPTEM) to treat advanced neuroendocrine neoplasms: A meta-analysis

Retrospective studies have suggested that capecitabine combined with temozolomide (CAPTEM) is effective for treating patients with advanced neuroendocrine neoplasms (NENs); however, the efficacy and safety of this regimen needs to be verified by high-quality evidence or results of randomized controlled trials.We carried out a meta-analysis to evaluate the safety and effectiveness of a CAPTEM protocol for patients with advanced NENs. Systematic electronic literature searches were conducted using PubMed, EMBASE, and the Cochrane Library, and among meeting abstracts of the American Society of Clinical Oncology, European Society for Medical Oncology, European Neuroendocrine Tumor Society, and North American Neuroendocrine Tumor Society, up to June 30, 2017. We selected studies describing CAPTEM regimens for treating advanced NENs and reported on tumor response and/or toxicities according to clear World Health Organization (WHO) grading of patients. Three reviewers independently and repeatedly identified studies, extracted data, and assessed the quality of the literature. A single-proportion meta-analysis was applied to included articles.Fifteen studies with a total of 384 individuals were included. Medium overall survival in most studies was more than 12 months, whereas medium progression-free survival was similar or slightly higher than that in studies using other treatment regimes. Disease control rate of CAPTEM administration for patients with NENs was 72.89% (95% confidence interval, 64.04-81.73%; I = 82.4%; P < .01). WHO grade 3 to 4 toxicities, such as thrombocytopenia (3.36%), neutropenia (0.69%), lymphopenia (0.65%), anemia (0.59%), mucositis (0.57%), fatigue (0.54%), diarrhea (0.49%), nausea (0.39%), and transaminase elevation (0.13%) were reported in the trials included.CAPTEM is effective and relatively safe for treating patients with advanced NENs.

Advanced neuroendocrine tumours of the small intestine and pancreas: clinical developments, controversies, and future strategies

In this Review, we discuss clinical developments and controversies in the treatment of neuroendocrine tumours (NETs) that are relevant for clinicians and clinical researchers. We describe advances in genetics, blood-based biomarkers, functional imaging, and systemic therapy of advanced NETs and discuss results of recent phase 3 studies, systemic treatment of advanced disease with peptide receptor radionuclide therapy, biotherapy, chemotherapy, and molecularly targeted therapy, and the potential role of immunotherapy in the treatment of NETs. Suggested treatment algorithms for NETs of ileal or jejunal origin and of pancreatic origin are presented.

[Neuroendocrine tumors of the breast: Myth or reality? A systematic review]

Primary neuroendocrine breast carcinomas are rare and little-known tumors. Only a limited number of studies on neuroendocrine breast carcinomas have been reported in the literature, and the vast majority of them are small retrospective series or case reports. According to the World Health Organization (WHO), they account for only 2 % to 5 % of breast cancers. Their diagnosis relies on the presence of a neuroendocrine architecture and the expression of neuroendocrine markers (chromogranin A and/or synaptophysin). The revised 2012 WHO classification subdivides them into three categories: (i) well-differentiated neuroendocrine carcinomas, (ii) poorly differentiated neuroendocrine carcinomas or small-cell carcinomas, and (iii) invasive breast carcinomas with neuroendocrine differentiation. Their clinical features and radiological characteristics are not different from those of other types of breast cancer. Because of discordant results, their clinical outcome is still poorly defined. So far, no standard treatment has been established, and most clinicians draw on their experience of invasive ductal cancer. The role of specific treatments like platinum-based chemotherapy, somatostatin analogues, peptide receptor radionucleide therapy or temozolomide remains unclear. A better knowledge of the molecular pathways involved in their carcinogenesis could help to identify new potential therapeutic targets. The efficacy of targeted therapies has to be studied.

Combination therapy with capecitabine and temozolomide in patients with low and high grade neuroendocrine tumors, with an exploratory analysis of O6-methylguanine DNA methyltransferase as a biomarker for response

Recent advances in the treatment of neuroendocrine tumors (NET), including the combination regimen of capecitabine and temozolomide (CAPTEM), have mostly focused on grade 1 and 2 pancreatic neuroendocrine tumors (pNET). We undertook a retrospective review of 38 patients with advanced NET treated with CAPTEM, including patients with non-pancreatic tumors as well as grade 2 and 3 tumors. O⁶-methylguanine DNA methyltransferase (MGMT) expression was assessed as a predictive biomarker. We found that CAPTEM demonstrated activity in patients with all grades and in pNET and non-pNET. Median progression free survival (mPFS) was 13.0 months (95% CI: 5.6-17.0) and median overall survival (mOS) 29.3 months (95% CI 17.7 - 45.3). Among evaluable patients, there were 11 (38%) partial responses, 15 (52%) stable disease, and 3 (10%) progressive disease for a disease control rate of 90%. A higher rate of partial responses occurred in patients whose tumors had low levels of MGMT expression (63%) compared to intermediate-high (17%) (p=0.19). Our results show that CAPTEM therapy is active in patients with NET including in previously treated patients and in those with poorly-differentiated histology. We observed a trend towards increased response rate, median PFS, and median OS in patients whose tumors had low MGMT protein expression.

Treatment of Lung Carcinosarcoma and Other Rare Histologic Subtypes of Non-small Cell Lung Cancer

OPINION STATEMENT

Lung carcinosarcoma (PCS) and other histological subtypes of non-small cell lung cancer, such as primary pulmonary lymphoma (PPL), pulmonary carcinoid (PC), and primary pulmonary lymphoepithelioma-like carcinoma (LELC), are rare. For their low incidence, the diagnosis and treatment are still controversial. Some patients only need surgery, while others may need chemotherapy, radiotherapy, or targeted therapy. In this paper, we retrospectively reviewed the literature of some rare histological subtype of NSCLC for the recent 20 years, and try to get some conclusions.

Increased Grade in Neuroendocrine Tumor Metastases Negatively Impacts Survival

BACKGROUND

Tumor grade is an important predictor of survival in gastroenteropancreatic (GEP) neuroendocrine tumors (NETs), as determined by Ki-67 expression and mitotic rate. NETs generally grow indolently, but some cells may acquire traits facilitating metastasis. It is unclear how frequently metastases differ in grade from their primary tumors, and whether increasing grade in metastases affects prognosis.

METHODS

Ki-67 immunohistochemistry was performed on resected GEPNET specimens and cases with results for both primary tumors and concurrent metastases were identified. Grade was determined using a modified World Health Organization classification (Ki-67: G1 = 0-2%; G2 > 2-20%; G3 > 20%).

RESULTS

Ki-67 was performed on both the primary tumor and metastases in 103 patients. Tumor grade was higher in metastases from 25 (24%) patients, 24 increased from G1 to G2, and 1 increased from G2 to G3; 68 (66%) patients had no change in grade (42 G1 and 26 G2), and 10 (10%) decreased from G2 to G1. No clinicopathologic factors were predictive of higher grade in metastases. The 5-year progression-free survival (PFS) was 55% for patients with stable grade versus 8% of patients with increased grade, while 5-year overall survival (OS) was 92 and 54%, respectively. The 5-year OS of patients who had stable grade with G1 and G2 primaries was 92 and 64%, respectively.

CONCLUSIONS

Nearly one-third of patients had metastases with a different grade than their primary, and, when grade increased, both PFS and OS significantly decreased. Determining the grade in both the primary tumor and a metastasis is important for estimating prognosis and to help inform decisions regarding additional therapies.

The potential of combi-molecules with DNA-damaging function as anticancer agents

DNA-damaging agents, such as methylating agents, chloroethylating agents and platinum-based agents, have been extensively used as anticancer drugs. However, the side effects, high toxicity, lack of selectivity and resistance severely limit their clinical applications. In recent years, a strategy combining a DNA-damaging agent with a bioactive molecule (e.g., enzyme inhibitors) or carrier (e.g., steroid hormone and DNA intercalators) to produce a new 'combi-molecule' with improved efficacy or selectivity has been attempted to overcome these drawbacks. The combi-molecule simultaneously acts on two targets and is expected to possess better potency than the parent compounds. Many studies have shown DNA-damaging combi-molecules exhibiting excellent anticancer activity in vitro and in vivo. This review focuses on the development of combi-molecules, which possess increased DNA-damaging potency, anticancer efficacy and tumor selectivity and reduced side reactions than the parent compounds. The future opportunities and challenges in the discovery of combi-molecules were also discussed.

Refractory carcinoid syndrome: a review of treatment options

Carcinoid syndrome (CSy) is a constellation of symptoms that may commonly present in patients with well differentiated neuroendocrine tumors (NETs), with somatostatin analogs (SSAs) being the first-line option for symptom management. However, symptomatic progression eventually occurs and in this scenario of a refractory CSy; several treatment options have been studied such as dose escalation of SSA, interferon and liver-directed therapies. Nevertheless, recent phase III trials have contributed to the understanding and management of this condition. We performed a comprehensive review of interventional studies examining refractory CSy to provide the evidence for current treatment options and propose a treatment sequence.

New therapeutic approaches to metastatic gastroenteropancreatic neuroendocrine tumors: A glimpse into the future

Neuroendocrine (NE) gastroenteropancreatic tumors are a heterogeneous group of neoplasias arising from neuroendocrine cells of the embryological gut. Their incidence have increased significantly over the past 3 decades probably due to the improvements in imaging and diagnosis. The recent advances in molecular biology have translated into an expansion of therapeutic approaches to these patients. Somatostatin analogs, which initially were approved for control of hormonal syndromes, have recently been proven to inhibit tumor growth. Several new drugs such as antiangiogenics and others targeting mammalian target of rapamycin pathways have been approved to treat progressive pancreatic neuroendocrine tumors (NETs) although their role in non-pancreatic is still controversial. The treatment of NETs requires a coordinated multidisciplinary approach. The management of localized NETs primarily involves surgical resection followed by surveillance. However, the treatment of unresectable and/or metastatic disease may involve a combination of surgical resection, systemic therapy, and liver-directed therapies with the goal of alleviating symptoms of peptide release and controlling tumor growth. This article will review the current therapeutic strategies for metastatic gastroenteropancreatic NETs and will take a glimpse into the future approaches.

Role of Locoregional and Systemic Approaches for the Treatment of Patients with Metastatic Neuroendocrine Tumors

Although gastroenteropancreatic neuroendocrine tumors are often perceived as being indolent tumors, more than half of the patients will harbor liver metastases at the time of diagnosis. Gastroenteropancreatic neuroendocrine tumors have the potential to be aggressive and resistant to therapy, making the integration of both locoregional and systemic therapy even more critical in the treatment of patients with locally advanced or metastatic lesions. Over the last several years, significant advancements have been made in the surgical treatment, liver-directed therapy, and medical management of gastroenteropancreatic neuroendocrine tumors. While surgical resection is the cornerstone of therapy, cytoreductive surgery, orthotopic liver transplantation, local ablation, and intra-arterial therapy all improve the prognosis of patients suffering with locally advanced or metastatic disease. In addition, great strides have been made in the medical management of gastroenteropancreatic neuroendocrine tumors, particularly with the evolution of novel molecular targeted therapy, such as everolimus and sunitinib. Hence, gastroenteropancreatic neuroendocrine tumor is becoming a disease process requiring more of a multi-disciplinary approach with the integration of both locoregional and systemic therapies for improved outcomes.