Liquid Biopsy-Driven Cetuximab Rechallenge Strategy in Molecularly Selected Metastatic Colorectal Cancer Patients.

Background: Rechallenge with EGFR inhibitors represents a promising strategy for patients with RAS wild type (WT) colorectal cancer (CRC) but definitive selection criteria are lacking. Recently, the RAS WT status on circulating tumor DNA (ct-DNA) emerged as a potential watershed for this strategy. Our study explored the liquid biopsy-driven cetuximab rechallenge in a RAS and BRAF WT selected population. Methods: CRC patients with RAS and BRAF WT both on tumor tissue and on ct-DNA at baseline receiving rechallenge with cetuximab were eligible for our analysis. Ct-DNA was analyzed for RAS-BRAF mutations with pyro-sequencing and nucleotide sequencing assays. Real-time PCR and droplet digital PCR were performed to confirm the RAS-BRAF mutational status. Results: A total of 26 patients were included in our analysis. In the global population, RR was 25.0%, median overall survival (mOS) was 5.0 months, and median progression-free survival (mPFS) was 3.5 months. Previous response to anti-EGFR was associated with improved mPFS (5.0 vs. 2.0 months, HR: 0.26, p = 0.048); anti-EGFR free interval > 14 months and anti-EGFR free interval > 16 months were associated with improved mPFS (respectively 7.0 vs. 3.0 months, HR: 0.27, p = 0.013 and not reached vs. 3.0 months, HR: 0.20, p = 0.002) and with improved mOS (respectively 13.0 vs. 5.0 months, HR: 0.27, p = 0.013 and 13.0 vs. 5.0 months, HR: 0.20, p = 0.002). Previous lines >2 were correlated with improved mPFS (4.0 vs. 1.0 month, HR: 0.05, p = 0.041) and with improved mOS (7.0 vs. 1.0 month, HR: 0.045, p = 0.034). In a multiple logistic regression model, only the anti-EGFR free interval was confirmed to be a significant predictor for mOS and mPFS. Conclusions: Liquid biopsy-driven cetuximab rechallenge was confirmed to be effective. The clinical outcome was consistent with available results from phase II studies. In addition to the molecular selection through the analysis of ct-DNA for RAS, the long anti-EGFR free interval is confirmed as a prospective selection criterion for this therapeutic option.

Retrospective Comparative Analysis of KRAS G12C vs. Other KRAS Mutations in mCRC Patients Treated With First-Line Chemotherapy Doublet + Bevacizumab.

BACKGROUND: KRAS mutations in metastatic colorectal cancer (mCRC) define a subset of tumors that have primary resistance to anti-EGFR-based therapy. Data concerning whether different KRAS mutations may also have a prognostic value are lacking. Furthermore, novel KRAS G12C inhibitors are currently in development. The aim of our analysis was to compare response rates in patients treated with first-line chemotherapy doublet + Bevacizumab among different KRAS variants. Secondary end-points were progression free survival (PFS) and overall survival (OS). METHODS: Patients with KRAS mutated mCRC treated with either FOLFIRI/FOLFOX/XELOX + Bevacizumab were eligible for enrollment. Patients whose tumor harbored NRAS mutations or that coexpressed also BRAF mutations were excluded from this retrospective analysis. Patients' individual data were collected from patients' records. Propensity score matching (nearest method, 1:2 ratio) was used to define the two different groups of patients for comparison (KRAS G12C mutated vs other KRAS variants). Eastern Cooperative Oncology Group Performance Status (ECOG PS), sex, metastatic site of involvement, synchronous vs metachronous metastatic disease, tumor sidedness, mucinous histology, primary tumor surgery, more than two lines of treatment for metastatic disease, and radical surgery of metastases were used as matching factors. Response rate (RR) was calculated by RECIST 1.1 criteria. Both progression free-survival and overall survival were calculated by Kaplan-Meier method. Categorical variables were compared by Fisher exact test for binomial variables and by chi-square test for all other instances. The level of statistical significance p was set at 0.05 for all tests. RESULTS: A total of 120 patients were assessed in the final analysis. Out of the 120 patients, 15 (12%) were KRAS G12C mutated. In the whole cohort of patients, 59/120 (49%) had partial response (PR), 42/120 (35%) had stable disease (SD), and 19/120 (16%) had progressive disease (PD) as the best response. In KRAS G12C patients, 4/15 (27%) had PR, 6/15 (40%) had SD, and the remaining 5/15 (33%) had PD as the best response. In patients with other KRAS mutations, 55/105 (52%) had PR, 37/105 (35%) had SD, and the remaining 13/105 (12%) had PD as the best response. The difference in RR between the two groups of patients was statistically significant (p=0.017). On the other hand, no difference in PFS (p=0.76) and OS (p=0.56) was observed. After matching procedures, the difference in response rates between KRAS G12C mutated patients vs the matched cohort of patients with other KRAS mutations remained statistically significant (p=0.016). KRAS G12C mutations were not associated with differences in sites of metastatic involvement, sex, and ECOG PS. On the other hand, synchronous vs metachronous metastatic disease (p=0.039), age > 75 years (p=0.043), and mucinous histology (p=0.008) were more frequent in G12C mutated tumors. CONCLUSIONS: In our cohort of patients, it was observed that KRAS G12C mutations are associated with worse response rates compared to other KRAS variants when treated with standard chemotherapy doublet + Bevacizumab. On the other hand, both PFS and OS were not significantly different. Based on these findings, we believe that new treatment options focused on KRAS G12C inhibition should be tested mainly in first-line setting and in addition to standard chemotherapy doublet + Bevacizumab for mCRC patients, as they might "fill the gap" in response rates that was seen in our study.

Beyond Microsatellite Instability: Evolving Strategies Integrating Immunotherapy for Microsatellite Stable Colorectal Cancer.

OPINION STATEMENT: Advanced colorectal cancer (CRC) is a heterogeneous disease, characterized by several subtypes with distinctive genetic and epigenetic patterns. During the last years, immune checkpoint inhibitors (ICIs) have revamped the standard of care of several tumors such as non-small cell lung cancer and melanoma, highlighting the role of immune cells in tumor microenvironment (TME) and their impact on cancer progression and treatment efficacy. An "immunoscore," based on the percentage of two lymphocyte populations both at tumor core and invasive margin, has been shown to improve prediction of treatment outcome when added to UICC-TNM classification. To date, pembrolizumab, an anti-programmed death protein 1 (PD1) inhibitor, has gained approval as first-line therapy for mismatch-repair-deficient (dMMR) and microsatellite instability-high (MSI-H) advanced CRC. On the other hand, no reports of efficacy have been presented in mismatch-repair-proficient (pMMR) and microsatellite instability-low (MSI-L) or microsatellite stable (MSS) CRC. This group includes roughly 95% of all advanced CRC, and standard chemotherapy, in addition to anti-EGFR or anti-angiogenesis drugs, still represents first treatment choice. Hopefully, deeper understanding of CRC immune landscape and of the impact of specific genetic and epigenetic alterations on tumor immunogenicity might lead to the development of new drug combination strategies to overcome ICIs resistance in pMMR CRC, thus paving the way for immunotherapy even in this subgroup.

Safety and Efficacy of Degradable Starch Microspheres Transcatheter Arterial Chemoembolization as a Bridging Therapy in Patients with Early Stage Hepatocellular Carcinoma and Child-Pugh Stage B Eligible for Liver Transplant.

In patients with early-stage hepatocellular carcinoma, awaiting liver transplantation, current guidelines by AASLD and ESMO recommend a bridging therapy with a loco-regional treatment to prevent progression outside transplantation criteria. The standard of care in delaying disease progression has been recognized to be the transarterial chemoembolization. Permanent occlusion of tumor feeding vessels has effects on tumour stromal microenvironment by inducing intra- and intercellular signaling processes counteracting hypoxia, such as the release of vascular endothelial growth factor, a promoter of neoangiogenesis, tumour proliferation and metastatic growth. Among chemoembolization interventions, TACE with degradable starch microspheres represents an alternative to conventional cTACE and DEB-TACE and it minimizes detrimental effects on tumour stromal microenvironment, guaranteeing a transient occlusion of tumour feeding arteries and avoiding VEGF overexpression.Between January 2015 and September 2020, 54 consecutive patients with early-stage hepatocellular carcinoma and Child-Pugh stage B, who had undergone DSM-TACE as a bridging therapy while awaiting liver transplantation, were eligible for the study. A total of 154 DSM-TACE was performed, with a mean number of 2.85 procedures per patient. 18 patients (33.3%) succeeded in achieving liver transplantation, with a mean waiting time-to-transplantation of 11.7 months. The cumulative rates of patients still active on the WL at 6 months were about 91 and 93% when considering overall drop-out and tumour-specific drop-out respectively. Overall survival was about 96% at 6 months and 92% at 12 months. 17 patients experienced adverse events after the chemoembolizations. For patients with HCC in the transplant waiting list and within the Child-Pugh B stage, life expectancy may be dominated by the liver dysfunction, rather than by the tumour progression itself. In this population subset, the choice of LRT is critical because LRT itself could become a dangerous tool that is likely to precipitate liver dysfunction to an extent that survival is shortened rather than prolonged. Hence, the current study demonstrates that DSM-TACE is not far from being an ideal LRT, because it has an excellent safety profile, maintaining an efficacy that guarantees a clear advantage on the dropout rate with respect to the non-operative strategy, thus justifying its use.

An observational retrospective analysis of the main metastatic site and corresponding locoregional treatment as a prognostic factor in metastatic gastric cancer.

Despite novel drugs, the prognosis for patients with metastatic gastric cancer remains poor. In rare instances, locoregional therapies are used in addition to standard chemotherapy in patients with oligometastatic involvement. This type of approach has not been supported by solid published evidence. The aim of the present retrospective study was to assess the prognostic impact of factors such as metastatic site, tumour histology and locoregional treatment in patients with metastatic gastric cancer. A total of 184 patients with metastatic gastric or gastroesophageal junction adenocarcinoma who received at least one line of palliative therapy with doublet or triplet chemotherapy were enrolled in the current analysis. Median overall survival (OS) was 8.32 months (95% CI, 7.02-9.41) and median progression-free survival (PFS) was 4.16 months (95% CI, 3.24-5.08). Lung metastases vs. other sites of metastatic involvement [hazard ratio (HR), 0.27; P=0.0133] and intestinal histology (HR, 0.48; P=0.08) were significantly associated with an improved OS. Improved PFS was also observed (HR, 0.49; P=0.10 and HR, 0.72; P=0.08 for lung metastases and intestinal histology, respectively). Second line chemotherapy and locoregional treatment of metastases (surgery or radiotherapy) were associated with improved OS (HR, 0.52; P<0.0001 and HR, 0.35; P<0.0001, respectively). Multivariate analysis confirmed an independent prognostic role for OS only for locoregional treatment, second line treatment and intestinal histology. The present results suggested that the presence of lung metastases alone was not a relevant prognostic factor and was influenced by the availability of further lines of treatment or by locoregional treatments. Locoregional treatments in patients with oligometastatic disease should be offered as they allow prolonged survival in patients with otherwise relatively short life expectancy.

Systemic immune-inflammation index: a prognostic tiebreaker among all in advanced pancreatic cancer.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) detains a dismal prognosis and has a limited number of prognostic factors. Inflammation has been demonstrated to play a key role both in PDAC initiation and progression and several inflammation-based prognostic scores have been investigated in a wide range of malignancies. We compared the most analyzed inflammation-based prognostic scores in order to establish their potential impact on prediction of the outcome in advanced PDAC patients. METHODS: A total of 234 advanced PDAC patients undergoing first-line chemotherapy in our institute were retrospectively analyzed. Baseline clinicopathological and pre-treatment laboratory data were collected. Survival was estimated using Kaplan-Meier method and survival differences were evaluated using the log-rank test. Level of statistical significance P was set at 0.05. Only those variables that proved to be associated with statistically significant differences in outcome were compared in multivariate analysis using multiple Cox regression, as to identify their independent role and their relative power against each other. RESULTS: In the whole cohort, median overall survival (OS) was 8.7 months (95% CI: 7.8-9.4 months), median progression-free survival (PFS) was 3.8 months (95% CI: 3.1-4.2 months). At univariate analysis high systemic immune-inflammation index (SII) was related to shorter OS [hazard ratio (HR) =2.04, 95% CI: 1.59-4.19, P=0.0001] and PFS (HR =1.52, 95% CI: 1.11-2.20, P=0.01). This was maintained at multivariate analysis both for OS (HR =2.11, 95% CI: 1.29-3.46, P=0.003) and PFS (HR =1.64, 95% CI: 1.14-2.37, P=0.008), whereas other inflammation-based scores lost their independent role. Elevated SII (≥1,200) was associated with low albumin levels (P=0.03) and with elevated lactate dehydrogenase (LDH) (P=0.01). CONCLUSIONS: Elevated SII represents an independent negative prognostic factor above all others for both OS and PFS in advanced PDAC patients treated with first-line chemotherapy, thus confirming a pivotal role of systemic inflammation on PDAC progression and on patient outcome.

Impact of Polypharmacy for Chronic Ailments in Colon Cancer Patients: A Review Focused on Drug Repurposing.

Colorectal cancer is characterized by high incidence worldwide. Despite increased awareness and early diagnosis thanks to screening programmes, mortality remains high, particularly for patients with metastatic involvement. Immune checkpoint inhibitors or poly (ADP-ribose) polymerase (PARP)-inhibitors have met with disappointing results when used in this setting, opposed to other malignancies. New drugs with different mechanisms of action are needed in this disease. Drug repurposing might offer new therapeutic options, as patients with metastatic colorectal cancer often share risk factors for other chronic diseases and thus frequently are on incidental therapy with these drugs. The aim of this review is to summarise the published results of the activity of drugs used to treat chronic medications in patients affected by colorectal cancer. We focused on antihypertensive drugs, Non-Steroid Anti-inflammatory Drugs (NSAIDs), metformin, antidepressants, statins and antibacterial antibiotics. Our review shows that there are promising results with beta blockers, statins and metformin, whereas data concerning antidepressants and antibacterial antibiotics seem to show a potentially harmful effect. It is hoped that further prospective trials that take into account the role of these drugs as anticancer medications are conducted.

Acute Peripheral Motor Neuropathy Induced by Oxaliplatin-Correlated Hypokalaemia.

Neurotoxicity is one of the most common side effects of oxaliplatin-based therapy. Most patients who receive at least 3-4 months of treatment suffer from peripheral sensory neurotoxicity (PSN), characterised by the loss or impairment of tactile and proprioceptive sensory function. Motor impairment, such as muscle weakness or palsy, has been rarely described, and the physiopathology of PSN, as well as the motor symptoms due to oxaliplatin-based treatment, are not adequately understood. Here we report the case of a patient who experienced severe acute peripheral motor neuropathy as a side effect of oxaliplatin-based treatment. We also review other cases of PSN published in the literature and suggest a novel hypothesis on the physiopathology of this particular event. Take-away lessons: Not all of the neurological symptoms observed during oxaliplatin-based treatment can be traced back directly to the oxaliplatin itself, and other factors, such as electrolyte imbalances, may contribute to the symptoms. Patients with gastro-intestinal malignancies are the patients most affected by neurotoxicity due to the side effects of chemotherapy and the disease itself.