Addition of Bevacizumab to First-Line Palliative Chemotherapy in Patients with Metastatic Small Bowel Adenocarcinoma: A Population-Based Study

Genomic landscape and clinical impact of homologous recombination repair gene mutation in small bowel adenocarcinoma

BACKGROUND

Small bowel adenocarcinoma (SBA) is a rare malignancy with a poor prognosis and limited treatment options. Although homologous recombination deficiency has been studied as a biomarker for other cancer types, the clinical and genomic implications of homologous recombination repair (HRR) gene mutations in SBA remain unclear.

METHODS

We retrospectively analyzed the data of 628 patients with advanced or recurrent SBA from a nationwide genomic database. Patients were categorized into HRR mutation and non-HRR mutation groups and compared for their clinical and genomic characteristics including tumor mutational burden (TMB) and microsatellite instability-high (MSI-H) were compared. Treatment efficacy and overall survival (OS) were assessed based on HRR gene mutation status and primary tumor site (duodenal adenocarcinoma [DA] vs. small intestinal carcinoma [SIC]).

RESULTS

Patients with the HRR mutations had higher frequencies of TMB and MSI-H than those without the mutation (P < 0.0001). In DA, HRR gene mutation positivity was associated with improved OS and higher overall response rates (ORR) to platinum-based chemotherapy (OS: not reached vs. 23.5 months, P = 0.040; ORR: 33 % vs. 19 %, P = 0.046), whereas no significant associations were observed with SIC.

CONCLUSION

HRR gene mutation may be a potential biomarker for platinum-based chemotherapy efficacy in SBA, especially in DA, highlighting the need for site-specific therapies.

Small intestinal metastasis from primary breast cancer: a case report and review of literature

Small intestinal metastasis from primary breast cancer remains a rare clinical occurrence. Despite extensive research into its clinicopathological features and treatment options, the specific pathogenesis and optimal management strategies remain incompletely understood. This case report presents a patient with breast cancer that metastasized to the small intestine. The primary breast tumor was diagnosed as classic invasive lobular carcinoma. Subsequent surgical intervention successfully addressed the intestinal obstruction and confirmed the metastatic origin of the small intestinal tumor. Interestingly, the metastatic lesions exhibited features suggestive of pleomorphic lobular carcinoma. A PET-CT scan was performed to evaluate the distant metastasis status of this patient. Notably, hormonal receptor status shifted from positive to negative, while HER2 expression changed from negative to low between the primary tumor and metastatic lesions. The presence of an undiagnosed pleomorphic component in the primary tumor might explain the disease's progressive nature. In this case, systemic treatment with trastuzumab deruxtecan yielded favorable therapeutic outcomes. Overall, our findings suggest that re-evaluation of receptor status in breast cancer metastases is crucial for tailoring treatment strategies. Furthermore, a combination of palliative resection of small intestinal metastases and targeted therapy for HER2-low breast cancer may potentially improve survival.

Enhancing treatment strategies for small bowel cancer: a clinical review of targeted therapy and immunotherapy approaches

Small bowel cancer (SBC) is a rare and aggressive disease with a poor prognosis, necessitating the exploration of novel treatment approaches. This narrative review examines the current evidence on targeted therapy and immunotherapy for SBC, focusing on the two most common subtypes: adenocarcinoma and neuroendocrine tumor. A comprehensive search of PubMed, Scopus, and Google Scholar databases was conducted to identify relevant clinical trials and case reports published in English up to September 2023. The review includes 17 clinical trials and 10 case reports, indicating that targeted therapy and immunotherapy can have the potential to improve survival rates in patients with SBC. Notably, promising targeted medicines include bevacizumab, cetuximab, and trastuzumab, while pembrolizumab and nivolumab show potential as immunotherapies. However, it should be noted that the magnitude of the increase in survival rates with these interventions was small. Further research is needed to determine the optimal combination of targeted therapy and immunotherapy for individual patients with SBC.

Evaluation of Systemic Treatments of Small Intestinal Adenocarcinomas: A Systematic Review and Meta-analysis

Importance

Although small intestinal adenocarcinomas (SIAs) are rare, they have a poor prognosis, and the optimal treatment strategies are largely unknown. Because of the lack of high-quality evidence, guidelines for colorectal cancer are often followed in the treatment of SIAs.

Objective

To review the current evidence regarding survival benefit of systemic therapies, including chemotherapy, targeted agents, and immunotherapy, for patients with SIAs.

Data Sources

Following the Preferred Reporting Items for Systematic Reviews and Meta-analyses, MEDLINE and Embase were searched for articles published from January 1, 2005, until June 1, 2022.

Study Selection

Retrospective cohort studies and prospective phase 2 or 3 trials describing survival after systemic therapies for patients with SIAs were eligible for inclusion. Assessment of study eligibility was blinded and performed by 3 reviewers.

Data Extraction and Synthesis

The reviewers independently extracted data. Random effects, inverse variance, pairwise meta-analyses were performed.

Main Outcomes and Measures

Primary outcomes were overall survival (OS) and progression-free survival (PFS) of patients with SIAs after systemic therapies. Measures of interest included hazard ratios for survival and median survival times.

Results

Overall, 57 retrospective cohort and phase 2 studies of 35 176 patients were included. Adjuvant chemotherapy, generally fluoropyrimidine-based, was associated with increased OS in stage I to III SIAs (hazard ratio [HR], 0.60; 95% CI, 0.53-0.68), especially in stage III tumors (HR, 0.55; 95% CI, 0.48-0.64), irrespective of tumor localization. Palliative chemotherapy was also associated with an OS benefit (HR, 0.48; 95% CI, 0.40-0.58). Fluoropyrimidine-oxaliplatin combinations were superior to other regimens (OS: HR, 0.54; 95% CI, 0.30-0.99; PFS: HR, 0.46; 95% CI, 0.30-0.71). Furthermore, bevacizumab added to chemotherapy compared with chemotherapy alone was associated with significantly prolonged PFS (HR, 0.62; 95% CI, 0.43-0.89). Immunotherapy showed a 50% overall response rate in previously treated defective mismatch repair tumors.

Conclusions and Relevance

In this systematic review and meta-analysis, adjuvant and palliative chemotherapy were both associated with improved survival of patients with SIAs, especially fluoropyrimidine-based regimens and fluoropyrimidine-oxaliplatin combinations. Adding bevacizumab to chemotherapy appears to prolong PFS and deserves further investigation. Immunotherapy seems beneficial and should be considered for patients with defective mismatch repair tumors. International collaborations should be undertaken to confirm and improve efficacy of systemic therapies for patients with SIAs.

Small Bowel Adenocarcinoma: From Molecular Insights to Clinical Management

Small bowel adenocarcinoma (SBA) is a rare malignancy, with a rising incidence in recent decades, and accounts for roughly 40% of all cancers of the small bowel. The majority of SBAs arise in the duodenum and are associated with a dismal prognosis. Surgery remains the mainstay of treatment for localized disease, while systemic treatments parallel those used in colorectal cancer (CRC), both in the adjuvant and palliative setting. In fact, owing to the lack of prospective data supporting its optimal management, SBA has historically been treated in the same way as CRC. However, recent genetic and molecular data suggest a distinct profile from other gastrointestinal malignancies and support a more nuanced approach to its management. Herein, we briefly review the state-of-the-art in the clinical management of early-stage and advanced disease and recent discoveries of potentially actionable genetic alterations or pathways along with the most promising ongoing clinical trials, which will hopefully revolutionize the treatment landscape of this orphan disease in the foreseeable future.

Vascular endothelial growth factor-A is an Immunohistochemical biomarker for the efficacy of bevacizumab-containing chemotherapy for duodenal and jejunal adenocarcinoma

BACKGROUND

The efficacy and safety of bevacizumab-containing chemotherapy for patients with metastatic duodenal and jejunal adenocarcinoma (mDJA) are unclear. The present study aimed to evaluate the efficacy of bevacizumab and to explore immunohistochemical markers that can predict the efficacy of bevacizumab for patients with mDJA.

METHODS

This multicentre study included patients with histologically confirmed small bowel adenocarcinoma who received palliative chemotherapy from 2008 to 2017 at 15 hospitals. Immunostaining was performed for vascular endothelial growth factor-A (VEGF-A), TP53, Ki67, β-catenin, CD10, MUC2, MUC5AC, MUC6, and mismatch repair proteins.

RESULTS

A total of 74 patients were enrolled, including 65 patients with mDJA and 9 with metastatic ileal adenocarcinoma. Patients with mDJA who received platinum-based chemotherapy with bevacizumab as first-line treatment tended to have a longer progression-free survival and overall survival than those treated without bevacizumab (P = 0.075 and 0.077, respectively). Multivariate analysis extracted high VEGF-A expression as a factor prolonging progression-free survival (hazard ratio: 0.52, 95% confidence interval: 0.30-0.91). In mDJA patients with high VEGF-A expression, those who received platinum-based chemotherapy with bevacizumab as a first-line treatment had significantly longer progression-free survival and tended to have longer overall survival than those treated without bevacizumab (P = 0.025 and P = 0.056, respectively), whereas no differences were observed in mDJA patients with low VEGF-A expression.

CONCLUSION

Immunohistochemical expression of VEGF-A is a potentially useful biomarker for predicting the efficacy of bevacizumab-containing chemotherapy for patients with mDJA.

Metastatic small bowel adenocarcinoma: role of metastasectomy and systemic chemotherapy

Background

Metastatic small bowel adenocarcinoma (SBA) has a poor prognosis. Due to its rarity, high-quality data are lacking to guide treatment. This retrospective analysis was conducted to help characterize the treatment options for patients with metastatic SBA while providing clinically meaningful prognostic information.

Patients and methods

In total, 437 patients who initially presented with or developed metastatic SBA between September 1977 and September 2019 were identified from the MD Anderson Tumor Registry. Clinical data were collected from review of the medical record. Overall response rates (ORR), time to progression (TTP), and overall survival (OS) were assessed across various treatments and treatment lines.

Results

The median OS from diagnosis of metastatic disease was 15.9 months [95% confidence interval (CI): 14.3-17.9]. Seventy-five patients (17.1%) underwent metastasectomy, which was associated with a median OS of 34.5 versus 17.1 months among patients who received chemotherapy alone (P < 0.001). Fluoropyrimidine plus platinum (n = 164) was the most common first-line chemotherapy, associated with an ORR of 59% and TTP of 8.1 months. Irinotecan with 5-FU (n = 101) was the most common second-line therapy associated with an ORR of 31% and TTP of 4.0 months. Twenty-two patients received immunotherapy; 5 of 6 patients with deficient mismatch repair (dMMR) responded, while 0 of 16 with proficient mismatch repair (pMMR) responded. Taxane-based chemotherapy was given to 34 patients with an ORR of 21% and a median TTP of 2.4 months. Among 11 patients who received anti-epidermal-growth-factor-receptor (EGFR) monotherapy, the best response was stable disease (SD) in 1 patient.

Conclusions

In well-selected patients with SBA, metastasectomy appears to be associated with improved OS. This improvement was seen across metastasectomy sites, including liver, lung and peritoneal. Anti-programmed cell death protein 1 (PD-1) based immunotherapy was active for dMMR SBA but not pMMR SBA. While taxane-based chemotherapy demonstrates therapeutic activity, the activity of anti-EGFR therapy was limited.

•

Metastasectomy for well-selected metastatic SBA patients was associated with improved OS.

•

Anti-PD1-based immunotherapy was active for dMMR SBA but not pMMR SBA.

•

Taxane-based chemotherapy demonstrated clinical activity in refractory SBA.

•

Anti-EGFR therapy demonstrated minimal activity in SBA.