Localized Colonic Small-Cell Carcinoma with Pathological Complete Response after Neoadjuvant Cisplatin and Etoposide: A Case Report

Extrapulmonary small-cell carcinoma (SCC) is a rare neoplasm that shares certain features with its pulmonary counterpart and occurs predominantly in the gastrointestinal tract (GIT). It is a high-grade and poorly differentiated neuroendocrine tumor, usually diagnosed in advanced stages, with a poor prognosis and few therapeutic options in that setting. This is a case report of a 77-year-old Spanish male patient with localized SCC of the colon, who presented a pathological complete response in the surgical specimen after neoadjuvant chemotherapy with cisplatin and etoposide. To date, 5 years after surgery, the patient remains without evidence of tumor recurrence. As clinical guidelines for the management of this entity are lacking, and therefore its management has not been standardized, an attempt to summarize the current evidence in the literature was made.

Clinical and survival characteristics of patients with BRAF-mutated metastatic colorectal cancer (mCRC) who receive metastases surgery in a Spanish cohort

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Background: Patients with mCRC harboring BRAF mutation have worse prognosis and poor outcomes. However, those who have resectable metastatic disease and undergo surgery may have better outcomes compared to those who do not. Differences in clinical characteristics are not well known and may be critical to identify patients with better prognosis. Methods: We performed a retrospective analysis of 299 patients with mCRC in a tumor registry from 2015 to 2021. We compared the clinical characteristics and survival trends of both cohorts (BRAF mutated and BRAF wild type). Furthermore, we analyzed clinical and survival features of 23 patients with BRAF mutated mCRC who received metastases resection. Results: We identified 34 patients with BRAF mutation (11.37%). Several characteristics were significantly more frequent in this group: age <65 years (n = 24, OR 1.38, p = 0.03), female sex (n = 24, OR 1.74, p = 0.008), primary tumor in the right colon (n = 15, OR 1.93, p = 0.003), peritoneal carcinomatosis (n = 18, OR 2.29, p = 0.007) and increased CA19.9 levels at diagnosis (n = 18, OR 1.79, p = 0.003). They received more peritoneal surgery (n = 12, OR 4.27, p = 0.000) and less liver metastases resection (n = 7, OR 0.51, p = 0.011). Median PFS in the first line of treatment was shorter in patients with BRAF mutation (9.5 vs 12.6 months; HR 1.69; IC 95%: 1.16 – 2.45; p = 0.006); however, we did not found differences in OS. Within the 23 patients with BRAF mutated mCRC who underwent surgery (67,64%), we found significant differences compared with those without metastases surgery: primary tumor resection (n = 21, OR 2.51, p = 0.0017) and having a single metastatic location (n = 18, OR 2.04, p = 0.01). Other features were more frequent in patients who underwent surgery but did not reach statistical significance: right colon location (63.6% vs 37.5%), metachronic disease (47.8% vs 18.2%), normal CEA (50% vs 25%) and CA19.9 (45% vs 12%) at diagnosis, and receiving 3 or more lines of systemic treatment (57% vs 22%). Median PFS after metastasectomy was 14.9 months, but we found no differences between both groups. Conclusions: In our cohort, BRAF mutated mCRC patients were more frequently younger, women, had right-sided primary tumors, higher rates of peritoneal metastases and abnormal CA19.9 levels at diagnosis, including worse outcomes in terms of PFS. On the other hand, resection of the primary tumor and single metastatic location were associated with higher probability of having metastases surgery, although in this study no subsequent survival benefit was found, probably due to the small number of BRAF mutated patients analyzed.

Clinical characteristics and survival trends of patients with metastatic colorectal cancer (mCRC) and peritoneal carcinomatosis who receive metastases surgery in a Spanish cohort

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Background: Peritoneal metastases in patients with mCRC are commonly associated with poor outcomes. Some of these patients are candidates to undergo metastases surgery, which may result in better prognosis; however, clinical and molecular characteristics of these patients remain uncertain. Methods: We conducted a retrospective analysis of 166 patients with mCRC and peritoneal metastases in a tumor registry from 2015 to 2021, analyzing the clinical and molecular characteristics, as well as progression-free survival (PFS) and overall survival (OS) of patients who received peritoneal surgery versus those who did not. Results: From the whole population, 65 patients (39%) underwent peritoneal metastases surgery, and several characteristics were more frequent in this subgroup: ECOG 0 (n = 26, OR 2.75, p = 0,0069), age &lt;65 years (n = 43, OR 2.29, p = 0,0162), absence of hepatic metastases (n = 56, OR 3.31, p = 0,0037), single metastatic location (n = 43, OR 3.48, p = 0,0002), normal CEA levels at diagnosis (n = 33, OR 2.02, p = 0,0455) and BRAF mutation (n = 12, OR 3.32, p = 0,0345). Moreover, these patients received more lines of systemic treatment (2.8 vs 2, p = 0,006) and more metastases surgeries (1.7 vs 0.9, p = 0,000). Significant differences in tumor mutational status regardless of BRAF (KRAS, NRAS, MSI, PI3K and HER2), sex and primary tumor location between groups were not found. PFS was longer in patients receiving metastases surgery (median, 13.68 vs 7.76 months; HR for progression 0.64; 95 % confidence interval (CI) 0.46 to 0.89; p = 0,009), as well as overall survival (median NR vs 29.53; HR for death 0.39; 95 % CI, 0.25 to 0.60; p = 0,000). Conclusions: In our cohort, patients with mCRC and peritoneal carcinomatosis who underwent metastases surgery had more frequently less than 65 years, ECOG 0, absence of liver metastases, single metastatic location, normal CEA levels at diagnosis and BRAF mutation. Moreover, this subgroup showed better outcomes with a statistically significant increase in PFS and OS.

Limited T cell response to SARS-CoV-2 mRNA vaccine among patients with cancer receiving different cancer treatments

INTRODUCTION

Patients with cancer (PC) are at high risk of acquiring COVID-19 and can develop more serious complications. Deeper understanding of vaccines immunogenicity in this population is crucial for adequately planning vaccines programs. The ONCOVac study aimed to comprehensively assess the immunogenicity of mRNA-1273 vaccine in terms of humoral and cellular response.

METHODS

We conducted a prospective, single-center study including patients with solid tumours treated with cyclin-dependent kinases 4 and 6 inhibitors (CDK4/6i), immunotherapy (IT) or chemotherapy (CT). Patients were enrolled previously to vaccination with mRNA-1273. We also involved health care workers (HCW) to serve as a control group. We took blood samples before first dose administration (BL), after first dose (1D), and after second dose (2D). The primary objective was to compare the rate and magnitude of T cell response after second dose whereas safety and humoral response were defined as secondary objectives. We also collected patient reported outcomes after both the first and second vaccine dose and a six-month follow-up period to diagnose incident COVID-19 cases was planned.

RESULTS

The rate of specific anti-S serologic positivity (anti-S IgG cut-off point at 7,14 BAU/mL) was significantly higher in HCW compared to PC after 1D (100% versus 83.8%; p = 0.04), but similar after 2D (100% versus 95.8%; p = 0.5). This difference after 1D was driven by PC treated with CT (100% versus 64.5%; p = 0.001). Cellular response after 2D was significantly lower in PC than in HCW for both CD4+ (91.7% versus 59.7%; p = 0.001) and CD8+ (94.4% versus 55.6%; p < 0.001) T cells. We found a difference on pre-existing CD4+ T cell response in HCW comparing to PC (36% and 17%, p = 0.03); without difference in pre-existing CD8+ T cell response (31% and 23%, p = 0.5). After excluding patients with pre-existing T cell response, PC achieved even lower CD4+ (50.9% versus 95.5%, p < 0.001) and CD8+ (45.5% versus 95.5%, p < 0.001) T cell response compared with HCW. Regarding safety, PC reported notably more adverse events than HCW (96.6% versus 69.2%, p < 0.001).

CONCLUSION

We demonstrated that PC showed a similar humoral response but a lower T cell response following two doses of mRNA-1273 vaccination. Further studies are needed to complement our results and determine the implication of low T cell response on clinical protection of PC against COVID-19.

Analysis of survival trends, clinical, and molecular characteristics of patients with early-onset colorectal cancer (EOCRC)

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Background: Over the last decades the incidence of EOCRC (age 50 or less) has dramatically increased, and so has the scientific interest in this field, given that clinical and molecular characteristics in these patients are not well understood, and may be critical to identify prognostic factors. Methods: We conducted a retrospective analysis of 554 patients with metastatic colorectal cancer (mCRC), analyzing the PFS and OS of 68 (12.25%) patients with EOCRC, as well as their clinical and molecular characteristics. We used a log-rank test to compare PFS and OS, and the estimate of hazard ratio (HR) between the studied groups was calculated by means of Cox proportional hazard model. We also used the exact test of Fisher to identify significant association between categoric variants, while Mann-Whitney test was applied to identify significant differences between numeric values. Results: We performed a survival analysis: those patients with EOCRC had significantly higher median PFS in first line of treatment (16.2 vs. 11.3 months, p = 0.042) and significantly higher median OS (121.5 vs. 58.1 months, p = 0.011). Several characteristics were significantly more frequent in patients with EOCRC (n=68): BMI < 18.5 (n = 16, OR = 1.9, p = 0.046), primary tumor site at transverse colon (n = 9, OR = 2.61, p = 0.03) and ECOG 0 (n = 32, OR = 2.21, p = 0.003). Having peritoneal metastases almost reached statistical signification (n = 17, OR = 1.82, p = 0.055). Some other characteristics were less frequent: BMI 25-30 (n = 13, OR = 0.51, p = 0.046), primary tumor site at sigmoid colon (n = 14, OR = 0.49, p = 0.038) and former-smoker status (n = 7, OR = 0.44, p = 0.048). Moreover, mean values of LDH at diagnosis were significantly higher in EOCRC patients (359 U/L vs. 280 U/L, p = 0.015). EOCRC patients received a significantly higher number of lines of chemotherapy (2.94 vs. 2.38, p = 0.027) and underwent more surgeries (2,42 vs. 1.24, p < 0,001) than patients with > 50 years. Significant differences in tumor mutational status (BRAF, KRAS, NRAS, MSI, PI3K and HER2), sex, primary tumor resection or number of metastatic sites between groups were not found. Conclusions: This retrospective analysis showed that EOCRC patients had significant higher rates of PFS in first-line treatment and OS. Moreover, EOCRC patients had more frequently BMI < 18.5, primary tumor located at transverse colon and ECOG 0.

Incidence of venous thromboembolic disease (VTE) in a cohort of patients with colorectal cancer (CRC) according to KRAS, NRAS and BRAF status

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Background: A recent study has suggested that KRAS mutation could increase the risk of VTE in patients with CRC. The role of others biomarkers, such as BRAF, in this setting is unknown. The aim of this study is to analyze the incidence of cancer-associated thrombosis in a cohort of patients with CRC based on KRAS, NRAS and BRAF status. Methods: We performed a retrospective review of patients with metastatic CRC and KRAS/NRAS/BRAF status known, attended in the Medical Oncology Department of the Hospital General Universitario Gregorio Marañón (Madrid, Spain) between January 2010 and January 2018. Results: 194 patients were identified and included in the analysis. The median age was 64 years (18-86). Most were metastatic at diagnosis (58.1%). Khorana’s predictive model: low-risk 67.7%, intermediate-risk 31.0%, high-risk 2.3%. The median follow-up was 35 months (2-240). 41 patients (21.1%) experienced VTE (11 pulmonary embolism, 15 lower extremity deep-vein thrombosis, 12 visceral vein thrombosis, 2 catheter-related thrombosis, 1 unknown). Most had metastatic disease at the moment of VTE (90.2%). 40% of the events occurred at the time of diagnosis or within the first 6 months. 65% were incidental events. Khorana’s predictive model in VTE patients: low-risk 63.4%, intermediate-risk 24.5%, high-risk 7.3%. According to biomarkers, the incidence was 19.1% (13/68) in KRAS/NRAS mutated patients, 28.6% (6/21) in BRAF mutated patients and 21% (22/105) in triple-wild-type patients. 6/38 patients (15.8%) developed recurrent thrombosis. In the univariate analysis, the presence of chronic kidney disease (p = 0.022), ECOG ≥ 2 (p = 0.038) and high-risk Khorana score (p = 0.011) were significantly associated with increased risk of VTE. Metastatic disease showed a trend towards the statistical significance (p = 0.053). In the multivariate model, including this variables, age, sex and biomarkers, only ECOG ≥ 2 remained independent predictor of VTE (OR 8.73; CI 95% 1.32-57.82; p = 0.025). Conclusions: The biomarkers have not been associated with the risk of VTE. We have observed a high incidence of VTE in BRAF mutated patients that should be investigated in further studies.

Retrospective analysis of clinical characteristics of mCRC patients receiving three or more lines of chemotherapy

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Background: Prognostic and predictive factors are becoming more important in mCRC patients, and may have an impact in overall survival and in the number of lines of chemotherapy that a patient can receive. Methods: We conducted a retrospective analysis of 334 patients with mCRC. We analyzed the clinical characteristics of 113 (33.8%) mCRC patients who received ≥3 lines of chemotherapy. We apply the statistical test Chi square in order to identify significant association. Results: Several characteristics were significantly associated with receiving ≥ 3 lines of chemotherapy (n = 113): age < 80 years (n = 93, OR = 3.07, p = 0.001), ECOG 0-1 (n = 98, OR = 3.21, p = 0.055), primary tumor resection (n = 62, OR = 2.36, p = 0.000) and resection of metastases (n = 56, OR = 2.07, p = 0.002). Partial or complete response rate in the first line of chemotherapy was also significantly associated with receiving ≥ 3 lines of treatment (n = 65, p = 0.011). Tumor mutational status was analyzed in 333 patients: KRAS mutation was detected in 163 over 333 patients genotyped (48.9%), NRAS in 25/206 (12.1%), BRAF in 15/217 (6.9%) and PI3K in 31/213 (14.5%). In the group of patients receiving ≥ 3 lines of chemotherapy (n = 113): KRAS mutation was found in 60/113 patients (53.1%), NRAS in 5/77 (6.5 %), BRAF in 5/84 (5.9%) and PI3K in 8/80 (11.1%). Tumor mutations were not significantly associated with ≥ 3 lines of chemotherapy. No significant association was found between sex, tumor location (right [n = 33, 29.2%] or left [n = 76, 73%]), liver or lung isolated metastases and 3 or later lines of chemotherapy. We also performed in our database a survival analysis in the 334 patients: those who received ≥3 lines of chemotherapy had significantly higher survival rates (median OS 18 m in the group of < 3 lines of treatment vs. 37.2 m in the group of ≥ 3 lines of chemotherapy, HR = 1,6; CI 95% 1,2-2.1; p < 0,001). Conclusions: This retrospective analysis showed that mCRC patients with < 80 years, ECOG 0-1, primary tumor and or metastases resected and those with complete or partial response in the first line of treatment have a higher probability of receiving ≥ 3 lines of chemotherapy. [Table: see text]