Localized stomach cancer: Perioperative or postoperative approach? A meta‐analysis of phase III studies

Background and Aim

Despite the development and standardization of surgical techniques in the treatment of localized gastric adenocarcinoma, the loco‐regional and metastatic recurrence rate remains high. A combined radiochemotherapeutic regimen (the MacDonald regimen) as well as perioperative chemotherapy allows a significant improvement in the survival of patients with localized gastric adenocarcinoma with a reduction in the recurrence rate compared to surgery alone. The purpose of this review is to specify the best therapeutic approach in the treatment of localized gastric cancer.

Methods

We performed a systemic search of Medline, Embase, and the Cochrane Central Register of Controlled Trials using PubMed, Google Scholar, and Ovid without language restriction. Hazard ratio (HR) with 95% confidence interval (CI) was reported.

Results

We pooled 727 patients from two phase III randomized controlled trials. There was a benefit of perioperative chemotherapy versus surgery alone on the overall survival (OS) (HR = 0.72, 95% CI: 0.55–0.95) and on disease free survival (DFS) (HR = 0.65, CI: 0.50–0.85). Adjuvant chemotherapy was superior to surgery alone based on OS and disease free survival (CLASSIC study HR = 0.72, CI: 0.52–1 and HR = 0.56, CI: 0.44–0.72, respectively). Adjuvant radiochemotherapy was superior to surgery alone (HR = 1.35, 95% CI: 1.09–1.66; P = 0.005).

Conclusion

A face‐to‐face comparison of perioperative chemotherapy versus adjuvant chemotherapy versus chemoradiotherapy is necessary.

Optimal Timing to Surgery After Neoadjuvant Chemotherapy for Locally Advanced Gastric Cancer

BACKGROUND

The relationship between time to surgery (TTS) and survival benefit is not sufficiently demonstrated by previous studies in locally advanced gastric cancer (LAGC). This study aims to assess the impact of TTS after neoadjuvant chemotherapy (NACT) on long-term and short-term outcomes in LAGC patients.

METHODS

Data were collected from patients with LAGC who underwent NACT between January 2007 and January 2018 at our institution. Outcomes assessed were long-term survival, pathologic complete response (pCR) rate, and postoperative complications.

RESULTS

This cohort of 426 patients was divided into five groups by weeks of TTS. Under cox regression, compared to other groups, the 22-28 days and 29-35 days groups revealed a better OS (≤21 vs. 22-28 days: HR 1.54, 95% CI = 0.81-2.93, P = 0.185; 36-42 vs. 22-28 days: HR 2.20, 95% CI = 1.28-3.79, P = 0.004; 43-84 vs. 22-28 days: HR 1.83, 95% CI = 1.09-3.06, P = 0.022) and PFS (≤21 vs. 22-28 days: HR 1.54, 95% CI = 0.81-2.93, P = 0.256; 36-42 vs. 22-28 days: HR 2.20, 95% CI = 1.28-3.79, P = 0.111; 43-84 vs. 22-28 days: HR 1.83, 95% CI = 1.09-3.06, P = 0.047). Further analysis revealed a better prognosis in patients with TTS within 22-35 days (OS: HR 1.78 95% CI = 1.25-2.54, P = 0.001; PFS: HR 1.49, 95% CI = 1.07-2.08, P = 0.017). Postoperative stay was significantly higher in the ≤21 days group, while other parameters revealed no statistical significance (P > 0.05). Restricted cubic spline depicted the nonlinear relationship between TTS and OS/PFS.

CONCLUSION

Patients who received surgery within 3-5 weeks experienced the maximal survival benefit without an increase in postoperative complications or lowering the rate of pCR. Further investigations are warranted.

The importance of Epstein-Barr virus infection in the systemic treatment of patients with gastric cancer

The Epstein-Barr virus (EBV) may directly cause the development of EBV-associated gastric cancer (EBVaGC). The prevalence of EBVaGC ranges from 4% to 18%, with a 2-fold higher frequency in males, and in tumors arising in the gastric cardia or corpus and 4 times higher frequency in gastric stump carcinoma. The vast majority of EBVaGC are lymphoepithelioma-like carcinomas. Despite extensive nodal involvement and distant metastases at initial diagnosis, EBVaGC seems to be a distinct etiologic entity with a favorable prognosis. However, the lymphoepithelioma-like carcinomas subtype in EBVaGC cannot be recognized in the current molecular classifications. Neither is there an association between EBV positivity and survival of patients after curative gastrectomy if they received standard adjuvant chemotherapy, nor EBV positivity and prediction of response to neoadjuvant platinum/5-FU-based chemotherapy. Alterations in chemokines and PD-L1 provide theoretical justification for clinical evaluation of immune checkpoint therapy in EBVaGC. Moreover, a higher degree of host immune response was demonstrated in EBVaGC. The current histologic and molecular GC classification does not influence clinical practice. Further research is expected to find convenient methods to assess gastric subtypes in day-to-day practice and to tailor therapy to improve overall survival.

The Survival Benefit From the Addition of Radiation to Chemotherapy in Gastric Cancer Patients Following Surgical Resection

AIMS

The survival benefit of radiation therapy in gastric cancer patients who underwent curative resection remains contentious.

MATERIALS AND METHODS

Gastric cancer patients who underwent curative resection followed by adjuvant chemotherapy or chemoradiation therapy (CRT) between 2004 and 2014 were identified from the National Cancer Database. Survival analyses were carried out with the Kaplan-Meier method and the Cox regression model.

RESULTS

In total, 4347 patients were included in this study. Of these patients, 1185 patients received postoperative chemotherapy alone and 3162 patients received postoperative CRT. For all patients included in the analysis, patients who received CRT had significantly better overall survival than those who received chemotherapy alone (5-year overall survival: 54.8% versus 46.8%, P < 0.001). The survival benefit primarily occurred in patients with stage II (5-year overall survival: 58.7% versus 53.8%, P = 0.03), stage III (42.5% versus 30.3%, P < 0.001) and lymph node-positive (5-year overall survival: 52.2% versus 41.9%, P = 0.03) gastric cancer. Multivariable analysis confirmed the improvement in overall survival in patients who received postoperative CRT (hazard ratio = 0.78; 95% confidence interval, 0.661-0.926; P < 0.001) was independent of all known prognostic factors. For lymph node-positive patients with lymphovascular invasion (LVI), postoperative CRT significantly improved overall survival compared with chemotherapy alone (5-year overall survival: 49.0% versus 39.4%, P = 0.001). However, there was no survival difference between CRT and chemotherapy alone if lymph node-positive patients had no LVI (5-year overall survival: 54.5% versus 52.7%, P = 0.55).

CONCLUSION

The current study suggests that postoperative CRT provides a survival benefit in gastric cancer patients with concurrent lymph node-positive and LVI-positive disease. A randomised clinical trial may further evaluate the benefit of adjuvant CRT in this subgroup.

Optimal management of gastroesophageal junction cancer

Although recent decades have witnessed incremental improvements in the treatment of gastroesophageal junction (GEJ) carcinoma, outcomes remain modest. For locally advanced esophageal cancer, the addition of chemotherapy and/or radiation to surgery is considered the standard of care. Chemotherapy remains the primary treatment for metastatic disease and improves survival over best supportive care. However, the prognosis for patients with GEJ cancers, which are treated along the same paradigms as esophageal and gastric carcinomas, remain poor because of the emergence of chemoresistance and limited targeted therapeutic approaches, which include agents that target the HER2 and vascular endothelial growth factor pathways. Evaluation of immune checkpoint inhibitors in the chemorefractory setting have confirmed the activity of immunotherapy in esophagogastric cancer. Ongoing immunotherapeutic strategies are being evaluated in both the locally advanced and metastatic settings. This review focuses on the treatment of locally advanced and metastatic GEJ carcinomas, which encompass all tumors that have an epicenter within 5 cm proximal or distal to the anatomical Z-line (Siewert classification). Because the vast majority of GEJ tumors are adenocarcinoma, the management of adenocarcinoma is the focus of this review. Evolving approaches and areas of clinical equipoise are discussed.

Treatment in resectable non-metastatic adenocarcinoma of stomach: Changing paradigms

Adjuvant treatment in gastric adenocarcinoma has been a challenge for the treating specialists, and despite several trials, a clear consensus is yet to be defined. The higher propensity for lymph nodal involvement and locoregional recurrences led to the hypothesis that locoregional and systemic treatments need to be equally aggressive to achieve better outcomes in the management of gastric adenocarcinoma. Regional, ethnic, and biological differences between the Eastern and Western population are also found to reflect in the tumor behavior and its response to treatment. The MAGIC (Medical Research Council Adjuvant Gastric Infusional Chemotherapy), Intergroup 0116, ACTS-GC (Adjuvant Chemotherapy Trial of S-1 for Gastric Cancer), CLASSIC (Capecitabine and Oxaliplatin Adjuvant Study in Stomach Cancer), ARTIST (Adjuvant Chemoradiation Therapy in Stomach Cancer), and the recently published CRITICS (Chemoradiotherapy after Induction Chemotherapy in Cancer of the Stomach) trials were a few of the randomized controlled trials that tried to give a clearer perspective of this tumor, though it still remains a dilemma. A study incorporating the tumor and demographic factors along with the availability of skilled talent and resources might generate an answer.

Texture analysis of computed tomography data using morphologic and metabolic delineation of esophageal cancer-relation to tumor type and neoadjuvant therapy response

The prognostic values of image-based tumor texture analysis based on computed tomography (CT) and of limiting the segmented tumor volume to metabolically active regions using fludeoxyglucose-positron emission tomography (FDG-PET) were studied in 25 patients with esophageal adenocarcinoma and 11 patients with squamous cell carcinoma. The aims of this study are to describe their CT-image-based texture characteristics before and after neoadjuvant therapy and to evaluate whether limiting the examined tumor volume to metabolically active regions detected with FDG-PET image data would further improve their value. Textural parameters (homogeneity, energy, entropy, contrast, and correlation) based on gray-level co-occurrence matrices (GLCM) were calculated for 3D volumes of segmented esophageal tumors before and after neoadjuvant chemotherapy or radiochemotherapy. Histopathological data after surgical resection and textural parameters before and after neoadjuvant treatment were compared using the Mann-Whitney U test. Significant differences in the textural parameters were observed between adenocarcinoma and squamous cell carcinoma for homogeneity, energy, inertia, and correlation. The use of contrast media during scanning resulted in significant differences in homogeneity, energy, entropy, and inertia for adenocarcinoma but not squamous cell carcinoma. There was also a significant difference in all textural parameters between pathological T status for ypT0-ypT2 and ypT3-ypT4 adenocarcinomas, but not in squamous cell carcinoma patients. No additional value was found from using PET image data to aid segmentation of CT images.

Prognostic Value of Nodal Response After Preoperative Treatment of Gastric Adenocarcinoma

Background: Pathologically positive lymph nodes (ypN+) after preoperative chemotherapy are associated with poor survival in patients with gastric cancer. Little is known about the association between response to preoperative therapy and the benefit of postoperative therapy. Methods: This retrospective cohort study of the National Cancer Database included patients with clinically node-positive (cN+) gastric cancer treated with preoperative therapy followed by surgery (2006-2014). Preoperative treatment modality was categorized as the inclusion of radiation therapy (RT) or chemotherapy alone. Pretreatment clinical and pathologic stages were used to determine pathologic treatment response rates. The association between overall risk of death and preoperative treatment, disease response, and adjuvant therapy use was evaluated using multivariable Cox regression. Results: Preoperative RT was used in 53.6% of 1,976 patients with cN+ gastric cancer, (74.3% cardia and 10.1% noncardia). The nodal response rate was 38.9% and was higher with RT than with chemotherapy alone (cardia, 46.0% vs 29.1%; P<.001; noncardia, 43.8% vs 31.9%; P=.06). Preoperative RT was associated with an approximate 2-fold increase in the odds of pathologic response compared with chemotherapy. Overall, use of adjuvant therapy was not associated with a decreased risk of death. A primary tumor response with residual nodal disease was not associated with survival (hazard ratio [HR], 1.03; 95% CI, 0.66-1.60). However, a nodal response with residual primary disease was significantly associated with survival (HR, 0.54; 95% CI, 0.44-0.65). Conclusions: More than one-third of node-positive gastric cancers showed pathologic nodal response with preoperative treatment. RT is associated with a higher response than chemotherapy. Patients with ypN+ disease have worse survival, regardless of whether they receive postoperative therapy. Future gastric cancer trials should evaluate the role of preoperative RT and individualize postoperative therapy use.

Association between hospital volume and quality of gastric cancer surgery in the CRITICS trial

BACKGROUND

Studies investigating the association between hospital volume and quality of gastric cancer surgery are lacking. In the present study, the effect of hospital volume on quality of gastric cancer surgery was evaluated by analysing data from the CRITICS (ChemoRadiotherapy after Induction chemotherapy In Cancer of the Stomach) trial.

METHODS

Patients who underwent gastrectomy with curative intent in the Netherlands were selected from the CRITICS trial database. Annual hospital volume of participating centres was derived from the Netherlands Cancer Registry. Hospital volume was categorized into very low (1-10 gastrectomies per year per institution), low (11-20), medium (21-30) and high (31 or more), and linked to the CRITICS database. Quality of surgery was analysed by surgicopathological compliance (removal of at least 15 lymph nodes), surgical compliance (removal of indicated lymph node stations) and the Maruyama Index. Postoperative morbidity and mortality were also compared between hospital categories.

RESULTS

Between 2007 and 2015, 788 patients were included in the CRITICS study, of whom 494 were analysed. Surgicopathological compliance was higher (86·7 versus 50·4 per cent; P < 0·001), surgical compliance was greater (52·9 versus 19·8 per cent; P < 0·001) and median Maruyama Index was lower (0 versus 6; P = 0·006) in high-volume hospitals compared with very low-volume hospitals. There was no statistically significant difference in postoperative complications or mortality between the hospital volume categories.

CONCLUSION

Surgery performed in high-volume hospitals was associated with better surgical quality than surgery carried out in lower-volume hospitals.

Recent advances in the management of gastric adenocarcinoma patients

Gastric adenocarcinoma (GAC) is one of the most aggressive malignancies and has a dismal prognosis. Therefore, multimodality therapies to include surgery, chemotherapy, targeted therapy, immunotherapy, and radiation therapy are needed to provide advantage. For locally advanced GAC (>cT1B), the emerging strategies have included preoperative chemotherapy, postoperative adjuvant chemotherapy, and (occasionally) postoperative chemoradiation in various regions. Several novel therapies have been assessed in clinical trials, but only trastuzumab and ramucirumab (alone and in combination with paclitaxel) have shown overall survival advantage. Pembrolizumab has been approved by the US Food and Drug Administration on the basis of response rate only for patients with microsatellite instability (MSI-H) or if PD-L1 expression is positive (≥1% labeling index in tumor/immune cells in the presence of at least 100 tumor cells in the specimen). Nivolumab has been approved in Japan on the basis of a randomized trial showing significant survival advantage for patients who received nivolumab compared with placebo in the third or later lines of therapy. The cure rate of patients with localized GAC in the West is only about 40% and that for metastatic cancer is very poor (only 2-3%). At this stage, much more target discovery is needed through molecular profiling. Personalized therapy of patients with GAC remains a challenge.

Gastric cancer: French intergroup clinical practice guidelines for diagnosis, treatments and follow-up (SNFGE, FFCD, GERCOR, UNICANCER, SFCD, SFED, SFRO)

INTRODUCTION

This document is a summary of the French Intergroup guidelines regarding the management of gastric cancer published in October 2016, available on the website of the French Society of Gastroenterology (SNFGE) (www.tncd.org), updated in October 2017.

METHODS

This collaborative work was realized under the auspices of several French medical societies involved in management of gastric cancer. Recommendations are graded in three categories (A-C), according to the amount of evidence found in the literature until July 2017.

RESULTS

There are several known risk factors for gastric cancer, including Helicobacter pylori and genetic predispositions, both requiring a specific screening for patients and their relatives. The diagnosis and staging evaluation are essentially based on gastroscopy plus biopsies and computed tomography scan. The endoscopic ultrasonography can be used for superficial tumors in case of discussion for endoscopic resection (T1N0). For local disease (N+ and/or T > T1), the strategic therapy is based on surgery associated with perioperative chemotherapy. In the absence of preoperative treatment (for any raison), the postoperative chemoradiotherapy (or chemotherapy) should be discussed for patients with stage II or III tumor. For metastatic disease, the treatment is based on "palliative" chemotherapy consisting in a doublet or triplet regimens depending of age, performance status and HER2 tumor status. For patients with limited metastatic disease, surgical resection could be discussed in multidisciplinary meeting in case of stable disease after chemotherapy.

CONCLUSION

These guidelines in gastric cancer are done to help decision for daily clinical practice. These recommendations are permanently being reviewed. Each individual case must be discussed within a multidisciplinary team.

CURRENT STATUS OF THE MULTIDISCIPLINARY TREATMENT OF GASTRIC ADENOCARCINOMA

Background:

The complexity of the management of gastric cancer requires a multidisciplinary evaluation of patients with this tumor. Several treatments have been employed, associated to the surgical resection.

Objective:

To review the available therapeutic alternatives for the treatment of gastric adenocarcinoma.

Methods:

A review of selected articles on multidisciplinary treatment of gastric adenocarcinoma in the Pubmed and Medline databases between 2000 and 2017 was carried out. The following headings were related: stomach cancer, treatment, chemotherapy and radiotherapy.

Results:

There are several valid alternatives, with good results for the treatment of gastric cancer: chemoradiotherapy or chemotherapy in the adjuvant scenario; perioperative chemotherapy; and chemoradiotherapy after neoadjuvance with isolated chemotherapy.

Conclusion:

Current evidences suggest that combined multidisciplinary treatment is superior to surgery alone. However, the optimal treatment regimen is not yet established, and depends on a number of factors, especially the type of surgical resection employed. Therefore, the therapeutic decision should be made by a multidisciplinary team, assessing patient’s personal characteristics, biology of the tumor, residual disease, risks and side effects.

Is There a Precise Adjuvant Therapy for Esophagogastric Carcinoma?

Esophagogastric cancer remains a leading cause of cancer-related mortality worldwide. The prognosis for patients with locally advanced disease is poor and the majority of patients with operable tumors treated with surgery alone will have recurrent disease. A multimodal approach to treatment with adjunctive chemotherapy or chemoradiotherapy is therefore the standard of care for these patients. However, there is no global consensus on the optimal treatment strategy and international guidelines vary. National clinical trials inform local practice: neoadjuvant, perioperative, and adjuvant chemotherapy and radiotherapy combinations are all possible treatment options in the management of resectable esophagogastric cancer. A number of clinical trials are ongoing, which seek to directly compare multimodal treatment options and hope to provide clarity in this area. Furthermore, increased understanding of the molecular and genetic features of esophagogastric cancer may help to guide management of operable disease by determining optimal patient selection through identification of predictive biomarkers of response and the application of novel targeted agents.

Automated VMAT planning for postoperative adjuvant treatment of advanced gastric cancer

Background

Postoperative/adjuvant radiotherapy of advanced gastric cancer involves a large planning target volume (PTV) with multi-concave shapes which presents a challenge for volumetric modulated arc therapy (VMAT) planning. This study investigates the advantages of automated VMAT planning for this site compared to manual VMAT planning by expert planners.

Methods

For 20 gastric cancer patients in the postoperative/adjuvant setting, dual-arc VMAT plans were generated using fully automated multi-criterial treatment planning (autoVMAT), and compared to manually generated VMAT plans (manVMAT). Both automated and manual plans were created to deliver a median dose of 45 Gy to the PTV using identical planning and segmentation parameters. Plans were evaluated by two expert radiation oncologists for clinical acceptability. AutoVMAT and manVMAT plans were also compared based on dose-volume histogram (DVH) and predicted normal tissue complication probability (NTCP) analysis.

Results

Both manVMAT and autoVMAT plans were considered clinically acceptable. Target coverage was similar (manVMAT: 96.6 ± 1.6%, autoVMAT: 97.4 ± 1.0%, p = 0.085). With autoVMAT, median kidney dose was reduced on average by > 25%; (for left kidney from 11.3 ± 2.1 Gy to 8.9 ± 3.5 Gy (p = 0.002); for right kidney from 9.2 ± 2.2 Gy to 6.1 ± 1.3 Gy (p <  0.001)). Median dose to the liver was lower as well (18.8 ± 2.3 Gy vs. 17.1 ± 3.6 Gy, p = 0.048). In addition, Dmax of the spinal cord was significantly reduced (38.3 ± 3.7 Gy vs. 31.6 ± 2.6 Gy, p <  0.001). Substantial improvements in dose conformity and integral dose were achieved with autoVMAT plans (4.2% and 9.1%, respectively; p <  0.001). Due to the better OAR sparing in the autoVMAT plans compared to manVMAT plans, the predicted NTCPs for the left and right kidney and the liver-PTV were significantly reduced by 11.3%, 12.8%, 7%, respectively (p ≤ 0.001). Delivery time and total number of monitor units were increased in autoVMAT plans (from 168 ± 19 s to 207 ± 26 s, p = 0.006) and (from 781 ± 168 MU to 1001 ± 134 MU, p = 0.003), respectively.

Conclusions

For postoperative/adjuvant radiotherapy of advanced gastric cancer, involving a complex target shape, automated VMAT planning is feasible and can substantially reduce the dose to the kidneys and the liver, without compromising the target dose delivery.

Electronic supplementary material

The online version of this article (10.1186/s13014-018-1032-z) contains supplementary material, which is available to authorized users.

Chemoradiotherapy versus chemotherapy as adjuvant treatment for localized gastric cancer: a propensity score-matched analysis

BACKGROUND

Treatment of localized gastric cancer (LGC) consists of surgical resection followed by adjuvant treatment. Both chemoradiation (CRT) and chemotherapy (CT) regimens have shown benefit in survival outcomes versus observation. However, there are few data comparing these approaches.

METHODS

This study included consecutive patients with LGC treated at Instituto do Cancer do Estado de Sao Paulo (ICESP) from 2012 to 2015. CRT was based on the INT-0116 regimen and CT consisted of a platinum and fluoropyrimidine doublet. Treatment choice was based on physician preference. Toxicity was evaluated for every cycle. Overall survival (OS) analysis was performed by Kaplan-Meier. A propensity score-matched analysis was performed to minimize selection bias.

RESULTS

A total of 309 patients were evaluated, 227 in CRT group and 82 in CT group. The most prevalent grade 3/4 toxicities in CRT and CT groups were: nausea/vomiting (9.25 vs 4.9%), fatigue (9.3% vs 2.4%), mucositis (4.4% vs 1.2%), neutropenia (37.8% vs 20.9%), febrile neutropenia (3.9% vs 0%), anemia (4.3% vs 6.1%), thrombocytopenia (2.6% vs 4.9%), neuropathy (0 vs 2.4%) and hand-foot syndrome (0.4% vs 2.4%). Two grade 5 toxicities (febrile neutropenia and anemia) occurred in CRT group. There was no difference in the pattern of recurrence. After a median follow-up of 23.5 months (CRT) and 20.6 months (CT), there was no difference in OS between groups.

CONCLUSIONS

CT and CRT present similar efficacy and tolerability as adjuvant treatment for LGC.

Adjuvant chemoradiation for gastric carcinoma: State of the art and perspectives

An estimated 990,000 new cases of gastric cancer are diagnosed worldwide each year. Surgical excision, the only chance for prolonged survival, is feasible in about 20% of cases. Even after surgery, the median survival is limited to 12 to 20 months due to the frequency of locoregional and/or metastatic recurrences. This led to clinical trials associating surgery with neoadjuvant or adjuvant treatments to improve tumor control and patient survival. The most studied modalities are perioperative chemotherapy and adjuvant chemoradiotherapy. To date, evidence has shown a survival benefit for postoperative chemoradiotherapy and for perioperative chemotherapy. Phase III trials are ongoing to compare these two modalities. The aim of this review is to synthesize current knowledge about adjuvant chemoradiotherapy in the management of gastric adenocarcinoma, and to consider its prospects by integrating modern radiotherapy techniques.

Medical management of gastric cancer: a 2017 update

Gastric cancer remains a considerable health burden throughout the world. The Cancer Genome Atlas (TCGA) analysis has recently unveiled 4 genotypes of gastric cancer with data not ready to change treatment strategy yet. A multimodality approach to therapy is the cornerstone of screening, diagnosing, staging, treating and supporting patients with gastric cancer. The evidence-based approach to localized gastric cancer (>cT1b) is to use an either preoperative or postoperative strategy to maximize the benefit of surgery. The focus of future research is to optimize chemotherapy regimens, determine the role of radiation therapy and investigate the effect of treatment timing. In metastatic gastric cancer, biologic therapies have been introduced targeting markers shown to be prognostic. The results of ongoing randomized controlled phase 3 trials using targeted and immunotherapy agents, either in combination or alone, have the potential to alter the current treatment landscape of advanced gastric cancer.

Factors contributing to variation in the use of multimodality treatment in patients with gastric cancer: A Dutch population based study

BACKGROUND

Substantial variation in the use of (neo) adjuvant treatment in patients with gastric cancer exists. The aim of this study was to identify underlying (organizational and process) factors associated with the use of perioperative therapy.

PATIENTS AND METHODS

Patients with resectable gastric cancer who underwent surgery between 2012 and 2014 were selected from the Dutch Upper gastrointestinal Cancer Audit (DUCA). The proportion of perioperatively treated patients was defined per hospital. Five hospitals with the lowest percentage (LP group) and 5 hospitals with the highest percentage (HP group) of perioperative therapy were identified. In the selected hospitals additional information was obtained from patients' medical records using a structured list with predefined variables.

RESULTS

In total, 429 patients (231 in LP group, 198 in HP group) from 9 different hospitals were included. Perioperative therapy was given in 16.0% of patients in the LP group compared to 40.4% in the HP group. In the LP group, patients were enrolled in a clinical trial less frequently (10.8% versus 26.8%, P<.001), and a higher percentage grade III-IV toxicity was observed during neoadjuvant treatment (25.7% versus 46.3%, P=.007). Multivariable analysis showed that, besides known casemix factors, consultation with ≥3 upper GI specialists prior to treatment decision was positively associated with initiating perioperative therapy (OR 2.08, 95% CI 1.19-3.66).

CONCLUSION

Results of this study confirm considerable hospital variation in the use of perioperative therapy in patients with gastric cancer. Besides known casemix factors, use of perioperative therapy was associated with the level of involvement of multidisciplinary care.

The Role of Systemic Therapy in Resectable Gastric and Gastro-oesophageal Junction Cancer

OPINION STATEMENT

Approximately 20% of patients with cancer of the stomach or gastro-oesophageal junction (GOJ) present with resectable disease. Long-term outcome after surgery alone in these patients is poor, and a combined treatment approach is the standard of care. The two approaches to managing patients with cancer of the GOJ are perioperative chemotherapy or preoperative chemoradiotherapy. Based upon the most recent evidence, patients treated with a perioperative approach and deemed suitable for a triplet regimen should be considered for pre- and post-operative FLOT (5-fluorouracil [5-FU], leucovorin, oxaliplatin and docetaxel) and those suitable for a doublet regimen should be considered for a fluoropyrimidine/platinum combination such as capecitabine and oxaliplatin. Alternatively, such patients may be considered for preoperative chemoradiotherapy according to the CROSS regimen. True gastric cancers may be treated with a perioperative approach or, as is commonly used in Asia, postoperative adjuvant chemotherapy.

Perioperative chemotherapy for resectable gastric cancer - what is the evidence?

The UK MAGIC trial published in 2006 was the first RCT to identify improved long-term survival rates using preoperative chemotherapy for resectable gastric or gastroesophageal cancer. Overnight, the treatment regimen impacted European guidelines. However, the majority of patients underwent limited lymph node dissection, and analyses of the rates of curative resection, downsizing and downstaging were not by intention to treat, rightfully raising concerns about their validity. For the subset of true gastric cancers, meta-analyses may even question the claims of improved long-term survival rates by present-day regimens. A rhetorical question can be posed as to whether downstaging and improved survival rates by preoperative (radio)-chemotherapy for cancers of the distal esophagus or gastric cardia, has confounded our conclusions on the (lack of) effect of present-day regimens of perioperative chemotherapy for true gastric cancers, let alone in a situation with proper lymph node dissection. At present, a plea can be made to move one step back and revert to an RCT with a surgery alone arm. Inclusion criteria and analyses of future RCTs must stratify on tumor location and the Lauren type and embrace the newly developed scheme of sub-classification of gastric cancers based on extensive molecular profiling as reported in the seminal Cancer Genome Atlas Study.

Treatment of localized gastric and gastroesophageal adenocarcinoma: the role of accurate staging and preoperative therapy

Gastric cancer is the third most common cause of cancer death worldwide, although it is not in the top 10 causes of cancer death in Northern America. Due to clear differences in incidence, screening, risk factors, tumor biology, and treatment between gastric cancers from Eastern and Western countries, our treatment is primarily guided by trials from Western countries. Patients undergo an extensive staging evaluation including high-quality CT imaging, endoscopic ultrasound, and diagnostic laparoscopy with peritoneal washings for cytology. Patients are presented in multidisciplinary conference with input from medical, radiation, and surgical oncology, in addition to further evaluation of existing studies and biopsy results by diagnostic radiology and pathology colleagues. Due to the well-documented difficulty in tolerating postoperative therapy, patients are frequently treated with preoperative chemotherapy and chemoradiotherapy. Extended lymph node (D2) dissection is routinely performed during subtotal or total gastrectomy. Ongoing trials in Western populations comparing preoperative chemotherapy to chemoradiotherapy will help inform the decision regarding the optimal treatment for patients with resectable gastric cancer. Additional studies are needed to identify predictors of treatment response to identify the optimal preoperative or perioperative approach. As peritoneal disease is the most common site of recurrence, studies are also urgently needed for more accurate methods of detecting peritoneal disease at diagnosis, and also investigating potential treatment modalities such as hyperthermic intraperitoneal chemotherapy.

Gastric Adenocarcinoma: A Multimodal Approach

Despite its declining incidence, gastric cancer (GC) remains a leading cause of cancer-related deaths worldwide. A multimodal approach to GC is critical to ensure optimal patient outcomes. Pretherapy fine resolution contrast-enhanced cross-sectional imaging, endoscopic ultrasound and staging laparoscopy play an important role in patients with newly diagnosed ostensibly operable GC to avoid unnecessary non-therapeutic laparotomies. Currently, margin negative gastrectomy and adequate lymphadenectomy performed at high volume hospitals remain the backbone of GC treatment. Importantly, adequate GC surgery should be integrated in the setting of a multimodal treatment approach. Treatment for advanced GC continues to expand with the emergence of additional lines of systemic and targeted therapies.

Gastric adenocarcinoma

Gastric cancers, with gastric adenocarcinoma (GAC) as the most common histological type, impose a considerable global health burden. Although the screening strategies for early detection have been shown to be successful in Japan and South Korea, they are either not implemented or not feasible in most of the world, leading to late diagnosis in most patients. Helicobacter pylori infection contributes to the development of many endemic GACs, and pre-emptive eradication or early treatment of this bacterial infection might provide effective primary prevention. GACs are phenotypically and genotypically heterogeneous. Localized (clinical stage I) GAC is best treated either endoscopically or with limited surgical resection, but clinical stage II or stage III tumours require multidisciplinary adjunctive approaches in addition to surgery. Although GAC is highly treatable in its early stages, advanced (clinical stage IV) GAC has a median survival of just ∼9-10 months. However, detailed molecular and immune profiling of GAC is yielding promise; early studies with immune checkpoint inhibitors suggest that GAC is amenable to immune modulation. Molecular studies have yielded a vast quantity of new information for potential exploitation. Nevertheless, advances against GACs have lagged compared with other tumours of similar incidence, and more research is necessary to overcome the obstacles to prolong survival.

Adjuvant radiotherapy improves overall survival in patients with resected gastric adenocarcinoma: A National Cancer Data Base analysis

BACKGROUND

For patients with resectable gastric adenocarcinoma, perioperative chemotherapy and adjuvant chemoradiotherapy (CRT) are considered standard options. In the current study, the authors used the National Cancer Data Base to compare overall survival (OS) between these regimens.

METHODS

Patients who underwent gastrectomy for nonmetastatic gastric adenocarcinoma from 2004 through 2012 were divided into those treated with perioperative chemotherapy without RT versus those treated with adjuvant CRT. Survival was estimated and compared using univariate and multivariate models adjusted for patient and tumor characteristics, surgical margin status, and the number of lymph nodes examined. Subset analyses were performed for factors chosen a priori, and potential interactions between treatment and covariates were assessed.

RESULTS

A total of 3656 eligible patients were identified, 52% of whom underwent perioperative chemotherapy and 48% of whom received postoperative CRT. The median follow-up was 47 months, and the median age of the patients was 62 years. Analysis of the entire cohort demonstrated improved OS with adjuvant RT on both univariate (median of 51 months vs 42 months; P = .013) and multivariate (hazard ratio, 0.874; 95% confidence interval, 0.790-0.967 [P = .009]) analyses. Propensity score-matched analysis also demonstrated improved OS with adjuvant RT (median of 49 months vs 39 months; P = .033). On subset analysis, a significant interaction was observed between the survival impact of adjuvant RT and surgical margins, with a greater benefit of RT noted among patients with surgical margin-positive disease (hazard ratio with RT: 0.650 vs 0.952; P for interaction <.001).

CONCLUSIONS

In this National Cancer Data Base analysis, the use of adjuvant RT in addition to chemotherapy was associated with a significant OS advantage for patients with resected gastric cancer. The survival advantage observed with adjuvant CRT was most pronounced among patients with positive surgical margins. Cancer 2017;123:3402-9. © 2017 American Cancer Society.

Exclusive neoadjuvant chemotherapy in locally advanced resectable gastric and gastro-esophageal junction adenocarcinoma

BACKGROUND

Perioperative chemotherapy improves the prognosis of patients with locoregionally advanced resectable gastric and gastro-esophageal junction adenocarcinoma. Nevertheless, only 50% of operated patients could receive the postoperative component chemotherapy. An exclusive preoperative chemotherapy is therefore an interesting strategy. We report the clinical course of patients with operable gastric and gastroesophageal junction adenocarcinoma treated with an intention of exclusive preoperative chemotherapy.

METHODS

The medical records of all consecutive patients with an operable gastric or gastroesophageal junction adenocarcinoma and treated with an intention of exclusive preoperative chemotherapy were analysed.

RESULTS

Between 1999 and 2014, 90 eligible patients were identified. Fifty-eight patients (64%) presented with clinical T3-T4 tumour and 63 (70%) had a lymph node involvement. Eighty (90%) patients were treated with 4 cycles of preoperative chemotherapy containing docetaxel, 5-fluorouracil (5FU) and a platinum salt. All patients had surgery with a D2 lymphatic dissection and R0 resection rates in 91% and 88% respectively. Median progression-free survival was 6.1 years (95% confidence intervals (CI): 1.6, NC) with median overall survival of 8.1 years (95% CI: 4.1, NC).

CONCLUSION

Our study suggests that an exclusive neoadjuvant approach when associated with a D2 lymph node dissection in resectable gastric and gastro-esophageal junction adenocarcinoma appears a feasible strategy with encouraging survival.

Locoregional relapse after gastrectomy with D2 lymphadenectomy for gastric cancer

BACKGROUND

Risk for and site of locoregional relapse have not been well studied in patients undergoing gastrectomy with D2 lymphadenectomy for gastric cancer.

METHODS

Patients who had undergone gastrectomy with D2 lymphadenectomy for gastric cancer between 2004 and 2007 were identified from an institutional database. The locoregional relapse rate was estimated by competing risk analysis, and risk groups were derived according to locoregional relapse risk using recursive partitioning analysis (RPA). The locations of nodal relapses were evaluated according to Japanese Classification of Gastric Carcinoma criteria.

RESULTS

Some 2618 patients were included. With a median follow-up of 78·0 (range 28·5-122·6) months, relapse was diagnosed in 471 of 2618 patients (18·0 per cent). The cumulative incidence of locoregional relapse at 5 years was 8·5 (95 per cent c.i. 7·4 to 9·6) per cent. The 5-year locoregional recurrence rates for high-risk (N3), intermediate-risk (N1-2) and low-risk (N0) groups were 32·4, 12·3 and 1·7 per cent respectively (P < 0·001). Among patients with regional relapse, 90·4 per cent had involvement outside the D2 dissected area, and the most commonly involved site was station 16b1. This pattern was maintained in the RPA risk groups (P = 0·329).

CONCLUSION

Locoregional relapse at 5 years after gastrectomy with D2 lymphadenectomy was 8·5 per cent, and was most often seen outside the D2 dissected area.

Potentially Curable Cancers of the Esophagus and Stomach

Gastric and gastroesophageal adenocarcinomas continue to be a major health burden globally and collectively represent the third leading cause of cancer death. Among patients with metastatic disease, most die of their cancer because of the limited number of modestly effective treatment regimens available today. The progress against these cancers has been slow compared with many other solid tumors despite many attempts. In-depth molecular profiling has also not been completed. Even when these cancers are localized, they impose considerable challenges for the patient, relatives, and treatment team alike. Localized gastric or gastroesophageal cancer is best managed with a multidisciplinary approach. This review focuses on the management of localized cancers by reviewing the current literature and explaining certain principles that help guide therapy for these patients. The future, however, will afford numerous opportunities, including exploitation of initial data from The Cancer Genome Atlas, to identify novel targets and drugs, harness the prowess of the immune system, and customize therapy for each patient.

Gastric cancer adjuvant therapy

From a global perspective, gastric cancer is one of the most common and lethal forms of cancer. The incidence of gastric cancer is very high in East Asia and varies considerably in countries of the Western hemisphere. Even after curative resection, the relapse rates are high in stages II and III. Therefore, adjuvant treatment with chemotherapy has been studied with positive results, especially in East Asian populations. In the Western World, where many locally advanced and borderline resectable gastric cancers are diagnosed, perioperative chemotherapy has become a standard of care. Perioperative chemotherapy increases the chances for curative resection. The additional role of radiation therapy, either in the neoadjuvant or in the adjuvant setting, needs to be defined by studies with a quality assurance for all treatment modalities.