Andrea Spallanzani

The evolving role of microsatellite instability in colorectal cancer: A review

Microsatellite instability (MSI) is a molecular marker of a deficient mismatch repair (MMR) system and occurs in approximately 15% of colorectal cancers (CRCs), more frequently in early than late-stage of disease. While in sporadic cases (about two-thirds of MSI-H CRCs) MMR deficiency is caused by an epigenetic inactivation of MLH1 gene, the remainder are associated with Lynch syndrome, that is linked to a germ-line mutation of one of the MMR genes (MLH1, MSH2, MSH6, PMS2). MSI-H colorectal cancers have distinct clinical and pathological features such as proximal location, early-stage (predominantly stage II), poor differentiation, mucinous histology and association with BRAF mutations. In early-stage CRC, MSI can select a group of tumors with a better prognosis, while in metastatic disease it seems to confer a negative prognosis. Although with conflicting results, a large amount of preclinical and clinical evidence suggests a possible resistance to 5-FU in these tumors. The higher mutational load in MSI-H CRC can elicit an endogenous immune anti-tumor response, counterbalanced by the expression of immune inhibitory signals, such as PD-1 or PD-L1, that resist tumor elimination. Based on these considerations, MSI-H CRCs seem to be particularly responsive to immunotherapy, such as anti-PD-1, opening a new era in the treatment landscape for patients with metastatic CRC.

The somatic affairs of BRAF: tailored therapies for advanced malignant melanoma and orphan non-V600E (V600R-M) mutations

BRAF V600R-M-D are uncommon mutations, not included in the experimental protocols of BRAF selective inhibitors. We report the evaluation of correlations among different types of BRAF somatic mutations in melanoma and their management with BRAF inhibitors. 21 patients with BRAF mutated metastatic melanoma were enrolled in the protocol with BRAF inhibitors for compassionate use at the University of Modena. Hot spot V600E mutations were found in 19 patients. V600R mutation and double (V600E -V600M) mutation were identified in two melanomas. In one case, V600K mutation was found. Two screening failures were noted. Mean progression free survival at follow-up of to 8 weeks, was 7.6 months. Five patients had a very short follow-up and the experimental protocol is still ongoing, so we cannot provide complete follow-up data. However, all of them are still under treatment and disease progression free. An objective response with few side effects was observed in all patients. in vitro studies with the aim of testing drug sensitivity.

Correlation between MGMT promoter methylation and response to temozolomide-based therapy in neuroendocrine neoplasms: an observational retrospective multicenter study

PurposeTemozolomide (TEM) based therapy has been reported being effective in the treatment of metastatic neuroendocrine neoplasms (NEN), with response rates ranging from 30 to 70%. Among patients affected by advanced glioblastoma or melanoma and treated with TEM, loss of tumoral O6-methylguanine DNA methyltransferase (MGMT) is correlated with improved survival. In NEN patients, the role of MGMT deficiency in predicting clinical outcomes of TEM treatment is still under debate.MethodsIn this study we evaluated 95 patients with advanced NENs undergoing treatment with TEM-based therapy. MGMT promoter methylation status was evaluated with two techniques: methylation specific-polymerase chain reaction or pyrosequencing.ResultsTreatment with TEM-based therapy was associated with an overall response rate of 27.4% according to RECIST criteria (51.8% of patients with and 17.7% without MGMT promoter methylation). Response to therapy, progression free survival and overall survival was correlated to MGMT status at univariate and multivariate analysis. Methylation of MGMT promoter could be a strong predictive factor of objective response and an important prognostic factor of a longer PFS and OS.ConclusionAccording to our results, MGMT methylation status, evaluated with methylation specific-polymerase chain reaction or pyrosequencing, should have an important role in patients with metastatic NENs, in order to guide therapeutic options. These results need further confirmation with prospective studies.

Regorafenib for Patients with Metastatic Colorectal Cancer Who Progressed After Standard Therapy: Results of the Large, Single-Arm, Open-Label Phase IIIb CONSIGN Study

BACKGROUND In the phase III CORRECT trial, regorafenib significantly improved survival in treatment-refractory metastatic colorectal cancer (mCRC). The CONSIGN study was designed to further characterize regorafenib safety and allow patients access to regorafenib before market authorization. METHODS This prospective, single-arm study enrolled patients in 25 countries at 186 sites. Patients with treatment-refractory mCRC and an Eastern Cooperative Oncology Group performance status (ECOG PS) ≤1 received regorafenib 160 mg once daily for the first 3 weeks of each 4-week cycle. The primary endpoint was safety. Progression-free survival (PFS) per investigator assessment was the only efficacy evaluation. RESULTS In total, 2,872 patients were assigned to treatment and 2,864 were treated. Median age was 62 years, ECOG PS 0/1 was 47%/53%, and 74% had received at least three prior regimens for metastatic disease. Median treatment duration was three cycles. Treatment-emergent adverse events (TEAEs) led to dose reduction in 46% of patients. Regorafenib-related TEAEs led to treatment discontinuation in 9%. Grade 5 regorafenib-related TEAEs occurred in <1%. The most common grade ≥3 regorafenib-related TEAEs were hypertension (15%), hand-foot skin reaction (14%), fatigue (13%), diarrhea (5%), and hypophosphatemia (5%). Treatment-emergent grade 3-4 laboratory toxicities included alanine aminotransferase (6%), aspartate aminotransferase (7%), and bilirubin (13%). Ongoing monitoring identified one nonfatal case of regorafenib-related severe drug-induced liver injury per DILI Working Group criteria. Median PFS (95% confidence interval [CI]) was 2.7 months (2.6-2.7). CONCLUSION In CONSIGN, the frequency and severity of TEAEs were consistent with the known safety profile of regorafenib. PFS was similar to reports of phase III trials. ClinicalTrials.gov: NCT01538680. IMPLICATIONS FOR PRACTICE Patients with metastatic colorectal cancer (mCRC) who fail treatment with standard therapies, including chemotherapy and monoclonal antibodies targeting vascular endothelial growth factor or epidermal growth factor receptor, have few treatment options. The multikinase inhibitor regorafenib was shown to improve survival in patients with treatment-refractory mCRC in the phase III CORRECT (N = 760) and CONCUR (N = 204) trials. However, safety data on regorafenib for mCRC in a larger number of patients were not available. The CONSIGN trial, carried out prospectively in more than 2,800 patients across 25 countries, confirmed the safety profile of regorafenib from the phase III trials and reinforced the importance of using treatment modifications to manage adverse events.

Immunotherapy in the treatment of colorectal cancer: a new kid on the block

In the last few years, the success of anti-PD1 and anti-PDL1 drugs in solid cancers treatment and the advances in molecular biology have provided new potential treatment strategies for patients with metastatic colorectal cancer. Unfortunately, only patients with mismatch repair deficiency seem to benefit from immunotherapy and they represent a small subset of the metastatic population. New ongoing studies focus on converting an immune ignorant tumour into an inflamed one by combination therapies and on introducing an immunotherapeutic approach in earlier stages of disease (neoadjuvant and adjuvant setting). In this review we summarize the current knowledge about the molecular and immune landscape of colorectal cancer and propose new potential combination strategies to enhance the efficacy

Beyond the Beyond: A Case of an Extraordinary Response to Multiple Lines of Therapy in a de novo Metastatic HER2-Negative Gastric Cancer Patient

Background: Gastric cancer is the fourth cause of cancer-related death in Europe and the prognosis of these patients remains dismal. It has been demonstrated that chemotherapy improved survival compared with best supportive care and recently, subsequent lines of therapy, also with new drugs, obtained positive results. Summary: We present the case of a patient diagnosed with a de novo metastatic gastric cancer who experienced an extraordinary long response to multiple lines of chemotherapy (FOLFOX6, paclitaxel plus ramucirumab, FOLFIRI, rechallenge with FOLFOX6). Key Message: Gastric cancer therapy should be considered as the result of a strategy based on the patient’s condition, and tolerance and response to various therapies. The emerging evidence of the role of subsequent lines of therapy, along with the recognition of the pivotal role of nutritional support and the availability of new drugs, should help clinicians in the management of patients with gastric cancer. Practical Implications: We propose a practical therapeutic algorithm in order to help clinicians who deal with patients with gastric cancer.

Lenvatinib as a therapy for unresectable hepatocellular carcinoma

ABSTRACT Introduction: Since 2007 Sorafenib has represented the only approved drug for first-line treatment of advanced hepatocellular carcinoma (HCC). Lenvatinib, an orally active inhibitor of multiple receptor tyrosine kinases (VEGFR 1–3, FGFR 1–4, PDGFRa, RET and KIT), showed preclinical and clinical activity in the treatment of solid tumors, including HCC. Areas covered: In this review, we summarize the current therapeutic paradigm for the systemic treatment of advanced HCC, focusing on Lenvatinib pre-clinical and clinical development. Keywords ‘Lenvatinib’, ‘ Target therapy’, ‘REFLECT trial’, ‘Hepatocellular carcinoma’, ‘HCC’, ‘Sorafenib’ were used for literature search on PubMed. Expert commentary: In Phase-III multicentric REFLECT trial Lenvatinib demonstrated a non-inferior overall survival (OS) compared to Sorafenib in the first-line treatment of advanced HCC, with a manageable toxicity profile, becoming a valid alternative option in the therapeutic repertoire of this disease. Nevertheless, the potential role of Lenvatinib in real-life clinical practice has still to be defined, especially in the light of the positive results that have been achieved with other new therapeutic agents (e.g. immunotherapy).

Advanced gastric cancer: is there an optimal chemotherapy regimen?

ABSTRACT Introduction: Gastric cancer (GC) is the fifth most common cancer and the third leading cause of cancer-related death worldwide. For patients with advanced gastric cancer (AGC), systemic chemotherapy remains the standard of care, improving survival and quality of life (QoL); however prognosis remains poor. Areas covered: Several clinical trials have been evaluated the efficacy of different combination regimens in AGC patients. This review will underline existing literature on the role of chemotherapy in the management of AGC, discussing the key determinants of treatment decision aiming at identify the optimal chemotherapy regimen for individual patients and the role of addition of biological agents in these regimens. Expert commentary: Despite the progress in understanding of the molecular subtypes of GC, chemotherapy remains the backbone of treatment for all-line setting in well-selected AGC patients. Moreover, several trials have failed to demonstrate a benefit of targeted agents and to date only trastuzumab and ramucirumab and apatinib only in China are approved in the treatment of this disease. Therefore, an improved patient selection before and during therapy with a better definition of predictive biomarkers are really needed.

A Dose-finding and Biomarker Evaluation Phase Ib Study of Everolimus in Association With 5-Fluorouracil and Pelvic Radiotherapy as Neoadjuvant Treatment of Locally Advanced Rectal Cancer (E-LARC Study)

Micro‐Abstract Neoadjuvant chemoradiation represents the mainstay of the treatment of locally advanced rectal cancer (LARC). However, despite substantial improvements in previous years, patients still develop relapses and eventually die of metastatic disease. In the present phase Ib dose‐escalation trial, everolimus added to standard chemoradiation did not seem to worsen toxicity. The activity of this combination warrants further evaluation in larger clinical trials. Background During the past 20 years, considerable improvement has occurred in the treatment of patients with locally advanced rectal cancer (LARC). With the introduction of multimodal treatment, refinements in preclinical staging and improvements in surgical skills, local relapse is no longer the major problem for patients with LARC. However, many patients die of metastatic disease. The present phase Ib study aimed to establish the maximum tolerated dose of everolimus combined with 5‐fluorouracil and radiotherapy in patients with LARC. Patients and Methods Patients were sequentially assigned to 4 cohorts with an increasing dose of everolimus, starting from 14 days before 5‐fluorouracil and radiotherapy and continuing throughout concomitant treatment. The secondary endpoints were the Dworak tumor regression grade, pathologic complete response rate, neoadjuvant rectal score, biomarker assessment (phosphorylated mTOR [mammalian target of rapamycin] protein and phosphorylated‐p70S6K protein). Results At the time of this report, 12 patients had been treated, and no dose‐limiting toxicity was recorded. The most frequently reported acute toxicities were rectal tenesmus, skin rash, diarrhea, and dysuria. All 12 patients underwent curative R0 resection. Two patients had Dworak tumor regression grade 4 (pathologic complete response). No everolimus‐related postoperative complications were observed. No relationship was found between biomarker expression and the clinicopathologic outcomes. Conclusion Although the addition of everolimus did not appear to worsen the toxicity of chemoradiation in patients with LARC, evaluation of its activity deserves further investigation in larger clinical trials.