Neoadjuvant or adjuvant therapy for resectable gastric cancer: a systematic review and practice guideline for North America

Immunosuppressive MFAP2+ cancer associated fibroblasts conferred unfavorable prognosis and therapeutic resistance in gastric cancer

PURPOSE

To explore the predictive merit of MFAP2+ cancer associated fibroblasts (CAFs) infiltration for clinical outcomes and adjuvant chemotherapy or immunotherapy responsiveness in gastric cancer (GC).

METHODS

In this study, several independent cohorts were included respectively to dissect the relationship of clinical outcomes, therapeutic responses and tumor microenvironment with different MFAP2+ CAFs infiltration. Drug sensitivity analysis was conducted to predict the relationship between MFAP2+ CAFs infiltration and targeted drug response. Kaplan-Meier curves and the log-rank test were used to compare clinical outcomes of patients with different MFAP2+ CAFs infiltration.

RESULTS

High MFAP2+ CAFs infiltration yielded inferior prognosis in terms of overall survival, progress free survival and recurrence free survival in GC. Patients with low MFAP2+ CAFs infiltration were more likely to gain benefit from adjuvant therapy. Moreover, low MFAP2+ CAFs infiltration could predict a promising response to immunotherapy in GC patients. MFAP2+ CAFs with immunosuppressive features were highly relevant to immune evasive contexture characterized by the dysfunction of CD8+ T cells. We found that MFAP2+ CAFs communicated with T cells, B cells and Macrophages through releasing macrophage migration inhibitor factor (MIF), which further suggested that MFAP2+ CAFs might promote therapeutic resistance through regulating T cells dysfunction and M2 macrophages polarization.

CONCLUSION

Immunosuppressive MFAP2+ CAFs constructed an immune evasive tumor microenvironment characterized by incapacitated immune effector cells, consequently predicting inferior clinical outcomes and response on adjuvant therapy and immunotherapy in patients with GC. The potential of immunosuppressive MFAP2+ CAFs as a therapeutic target for GC deserved thoroughly exploration.

Transcriptomic profiling on localized gastric cancer identified CPLX1 as a gene promoting malignant phenotype of gastric cancer and a predictor of recurrence after surgery and subsequent chemotherapy

BACKGROUND

Localized gastric cancer (GC) becomes fatal once recurring. We still have room for improving their prognoses.

METHODS

Transcriptomic analysis was done on surgically resected specimens of 16 patients with UICC stage III GC who underwent curative gastrectomy and adjuvant oral fluoropyrimidine monotherapy. Four of them were free from disease for longer than 5 years, and the others experienced metachronous metastasis within 2 years after surgery. Quantitative RT-PCR determined mRNA expression levels of primary gastric cancer tissues, which were collected from 180 patients who underwent gastric resection for stage II-III GC without preoperative treatment between 2001 and 2014. We tested alteration of malignant phenotypes including drug resistance of GC cell lines by siRNA and shRNA-mediated knockdown and forced expression experiments.

RESULTS

CPLX1 was identified as a candidate biomarker for GC recurrence among 57,749 genes. Inhibiting and forced expression experiments indicated that CPLX1 promotes proliferation, motility, and invasiveness of GC cells, and decreases apoptosis and sensitivity to fluorouracil. Subcutaneous xenograft mouse models revealed that shRNA-mediated knockdown of CPLX1 also attenuated tumor growth of MKN1 cells in vivo. Overexpression of CPLX1 in gastric cancer tissue correlated with worse prognosis and was an independent risk factor for peritoneal recurrence in subgroups receiving adjuvant chemotherapy.

CONCLUSIONS

CPLX1 may represent a biomarker for recurrence of gastric cancer and a target for therapy.

Neoadjuvant chemoradiotherapy for resectable gastric cancer: A meta-analysis

Objectives

To evaluate the clinical curative effects and toxicity of neoadjuvant chemoradiotherapy for resectable gastric cancer compared to those of neoadjuvant chemotherapy.

Methods

A systematic review and meta-analysis of the randomized controlled trials (RCTs) of neoadjuvant chemoradiotherapy versus neoadjuvant chemotherapy were performed in patients with resectable gastric cancer.

Results

Seven RCTs were included (601 patients; 302 in the neoadjuvant chemoradiotherapy group and 299 in the neoadjuvant chemotherapy group). The neoadjuvant chemoradiotherapy group had an increased number of patients with a complete response [odds ratio (OR) = 3.79, 95% confidence interval (CI): 1.68–8.54, p = 0.001] and improved objective response rate (OR = 2.78, 95% CI: 1.69–4.57, p < 0.0001), 1-year (OR = 3.51, 95% CI: 1.40–8.81, p = 0.007) and 3-year (OR = 2.14, 95% CI: 1.30–3.50, p = 0.003) survival rates, R0 resection rate (OR = 2.21, 95% CI: 1.39–3.50, p = 0.0008), and complete pathologic response (OR = 4.39, 95% CI: 1.59–12.14, p = 0.004). Regarding the incidence of adverse effects after neoadjuvant therapy, only the occurrence rate of gastrointestinal reaction in the neoadjuvant chemoradiotherapy group was higher than that in the neoadjuvant chemotherapy group (OR = 1.76, 95% CI: 1.09–2.85, p = 0.02), and there was no significant difference in other adverse effects. There was no difference in the incidence of postoperative complications between the two groups.

Conclusion

Neoadjuvant chemoradiotherapy for resectable gastric cancer has several advantages in terms of efficacy and safety compared to neoadjuvant chemotherapy. Therefore, neoadjuvant chemoradiotherapy has great potential as an effective therapy for resectable gastric cancers.

Systematic Review Registration

https://inplasy.com/inplasy-2022-3-0164, registration number INPLASY202230164.

Development and external validation of a prognostic nomogram for patients with gastric cancer after radical gastrectomy

Background

Gastric cancer (GC) is one of the most malignant diseases and threatens the health of individuals across the globe. Hitherto, the identification of prognosis risk stratification on GC has mainly depended on the TNM staging, but owing to its inaccuracy and incompleteness, the prognostic value it offers remains controversial in the current clinical setting. Thus, an effective prognostic model for GC after radical gastrectomy is still needed.

Methods

Patients with pathologically confirmed GC who underwent radical gastrectomy from 2 different centers were retrospectively enrolled into a training and the validation cohort, respectively. The least absolute shrinkage and selection operator (LASSO) algorithm was applied to select variables among multiple factors, including clinical characteristics, pathological parameters, and surgery- and treatment-related indicators. The multivariate Cox regression method was used to establish the model to predict 1-, 2-, and 3-year survival. Both internal and external validations of the nomogram were then completed in terms of discrimination, calibration, and clinical utility. Finally, prognostic risk stratification of GC was conducted with X-tile software.

Results

A total of 1,424 patients with GC were eligible in this study, including 1,010 in the training cohort and 414 in the validation cohort. Seven indicators were selected by LASSO to develop the nomogram, including the number of positive lymph nodes, tumor size, adjacent organ invasion, vascular invasion, the level of carbohydrate antigen 125 (CA 125), depth of invasion, and human epidermal growth factor receptor 2 (HER2) status. The nomogram demonstrated a robust predictive capacity with favorable accuracy, discrimination, and clinical utility both in the internal and external validations. Moreover, we divided the population into 3 risk groups of survival according to the cutoff points generated by X-tile, and in this way, the nomogram was further improved into a risk-stratified prognosis model.

Conclusions

We have developed a prognostic risk stratification nomogram for GC patients after radical gastrectomy with 7 available indicators that may guide clinical practice and help facilitate tailored decision-making, thus avoiding overtreatment or undertreatment and improving communication between clinicians and patients.

Laparoscopic D2 gastrectomy in advanced gastric cancer: Postoperative outcomes and long-term survival analysis

INTRODUCTION

Data on laparoscopic treatment of operable gastric cancer from India is sparse. This study aims to document outcomes of laparoscopic D2 gastrectomy in an Indian population.

MATERIALS AND METHODS

Data of patients who underwent laparoscopic D2 gastrectomy for operable advanced gastric cancer between February 2012 and January 2017 were collected from electronic hospital records supplemented by telephonic interviews and analyzed. Survival was evaluated using Kaplan-Meier survival analysis curves.

RESULTS

In total 121 patients were included. Conversion to open gastrectomy was 5.7%. One hundred and fourteen patients (73 laparoscopic subtotal gastrectomy and 41 laparoscopic total gastrectomy) were included for analysis. D2 lymphadenectomy was done in all cases; mean number of dissected lymph nodes was 23.12 ± 9.14 (12-45). Major complications (Clavien-Dindo Grade III and IV) was seen in 6.1% of cases with reoperation rate of 3.5% (4/114). Stage 3 disease was seen in 60.6% cases and stage 2 disease in 32.5%. Follow-up data were available for 76.3% of patients with mean follow-up of 29.5 months. Overall survival across all stages was 38.7 months. Five-year disease-free survival and overall survival were 36.7% and 55.9% respectively, across all stages.

CONCLUSION

Laparoscopic D2 gastrectomy is safe, feasible with similar postoperative complications and comparable survival outcomes across all stages when compared to available literature on open gastrectomy cases.

FLOT Neoadjuvant Chemotherapy Followed by Laparoscopic D2 Gastrectomy in the Treatment of Locally Resectable Advanced Gastric Cancer

BACKGROUND

The prognosis of patients with advanced gastric cancer remains unsatisfactory, highlighting the need for improved therapeutic strategies. We analyzed 23 resectable advanced gastric cancer patients who received FLOT followed by laparoscopic gastrectomy with D2 lymphadenectomy to evaluate the efficacy and safety.

METHODS

Patients aged 18-75 years with gastric adenocarcinoma (stage cT3-4 and/or N + M0) underwent neoadjuvant FLOT therapy (four preoperative and four postoperative 2-week cycles) at Shanghai East Hospital. Laparoscopic gastrectomy was scheduled 3-4 weeks after completion of the last cycle of preoperative chemotherapy. The type of surgical procedure was determined by the location and extent of the primary tumor.

RESULTS

23 patients were reviewed in the study. 20 patients (81.2%) received four courses of FOLT therapy, while 3 patients (18.8%) received three courses of treatment. There were 3 (13.0%) complete responses, 13 (56.5%) partial responses, 4 (26.1%) of stable disease, and 1 (4.3%) of progressive disease. The clinical efficacy response rate was 69.6%. The R0 resection rate was 91.3%. Only one patient exhibited grade III postoperative complications. The pathologic complete remission was 13%. The common grade 3/4 adverse events from chemotherapy were leucopenia (17.4%), neutropenia (30.4%), anemia (13%), anorexia (13%), and nausea (17.4%). Postoperative complications occurred in 5 patients (26.1%). There was no treatment-related mortality or reoperation. The most reason for not completing chemotherapy was the patient's request.

CONCLUSIONS

These findings suggest that FLOT neoadjuvant chemotherapy, followed by laparoscopic D2 gastrectomy, is effective and safe in advanced, resectable advanced gastric cancer.

In vivo antitumour activity of Britanin against gastric cancer through nuclear factor-κB-mediated immune response

OBJECTIVES

Britanin was explored for the antitumour effect on gastric cancer, which is a sesquiterpene lactone (SL) extracted from Inula japonica.

METHODS

In the present study, cell viability assays were performed to evaluate the antiproliferation effect of Britanin on gastric cancer cells. Tumour development in BGC-823 cell-bearing nude mice was monitored in real-time after Britanin treatment via a bioluminescent imaging method. Western blotting analysis and enzyme-linked immunosorbent assays detected proteins associated with the nuclear factor (NF)-κB signalling pathway.

KEY FINDINGS

Britanin can suppress the proliferation of gastric cancer cells in vitro and the growth of tumours in vivo. In the treatment group, decreased levels of p65 and phosphorylated (p)-p65 were observed. This indicated that NF-κB plays an important role in the antitumour effect of Britanin. Furthermore, considering the additional role of NF-κB in the immune system, the levels of the downstream molecules interleukin (IL)-2 and the cytokine IL-10 were subsequently determined in vivo. An increase in the IL-2 level and a decrease in the IL-10 level indicated that Britanin elicited an enhanced immune response.

CONCLUSIONS

Britanin may be a promising candidate for gastric cancer chemotherapy, and its anticancer effect likely depends on an NF-κB-mediated immune response.

Neoadjuvant Chemoradiation Treatment for Resectable Esophago-Gastric Cancer: A Systematic Review and Meta-Analysis

Background: Neoadjuvant chemoradiation (CRT) remains controversial in the treatment of the oesophagus or gastro-oesophageal junction (GOJ) carcinomas.

Methods: We conducted a meta-analysis to assess the efficacy and safety of Neoadjuvant CRT plus surgery comparing with neoadjuvant CT plus surgery or surgery alone. Feasible studies were searched from electronic databases. The outcomes of survival, R0 resection rate and adverse effects were analyzed. The outcomes were measured with relative risk (RR) and odds ratio(OR).

Results: Seventeen records including 4095 patients were included. Neoadjuvant CRT improved 1-,2-,3-and 5-year survival. The relative risk (RR) [95% confidence interval (CI),P value] was respectively 1.08(1.03-1.14,0.002), 1.21(1.12-1.32,<0.00001),1.31(1.09-1.58,0.004),1.38(1.17-1.62, <0.001).In subgroup analysis, patients with squamous cell carcinoma benefited more survival advantage from neoadjuvant CRT than those with adenocarcinoma[1.23(1.15-1.33)vs1.11 (1.03-1.19)]. A significant advantage was observed in analysis of neoadjuvant CRT for PFS [1.32 (1.22-1.44),<0.00001]. Tests for DFS between neoadjuvant CRT and neoadjuvant CT or surgery alone were not statistically significant[1.06 (0.97-1.17,0.19)]. Neoadjuvant CRT was associated with higher R0 resection [2.58(1.75-3.82),<0.00001] and pCR rate [4.37(2.68-7.13),<0.00001]. Neoadjuvant CRT lowered the local recurrence rate [0.52(0.39-0.69),<0.00001] and didn't control distant metastasis rate[0.85(0.67-1.08),0.19].There was no evidence that neoadjuvant CRT increased the treatment-related mortality[1.27(0.95-1.71),0.11]. Neoadjuvant CRT plus surgery did not increase the risk of adverse events morbidity[1.14(0.99-1.32),0.08].

Conclusion: Patients with oesophagus or GOJ carcinomas can obtain a survival advantage from neoadjuvant CRT. The addition of radiation was efficacy and safe in range. However, these results need further high-quality prospective RCTs confirmation.

Neoadjuvant therapy in gastric cancer: Current status and future perspectives

Gastric cancer (GC) remains one of the most common tumors in China. Most patients with GC in China are already in a locally advanced stage at the time of diagnosis. Neoadjuvant therapy has attracted increasing attention. Clinical literature and meta-analyses show that neoadjuvant therapy results in a significant survival benefit for resectable locally advanced GC, and preoperative chemoradiotherapy also should be a standard treatment for advanced GC vs surgery alone. The optimal regimens of neoadjuvant therapy and comparisons between preoperative chemotherapy and chemoradiotherapy still need to be studied further.

Preoperative Therapy for Gastric Adenocarcinoma is Protective for Poor Oncologic Outcomes in Patients with Complications After Gastrectomy

BACKGROUND

Postoperative complications (POC) are associated with poor oncologic outcomes in gastric cancer. We sought to evaluate the impact of POC on survival in patients with gastric cancer treated with upfront surgery (UpSurg) versus those treated with preoperative therapy (PreT).

METHODS

We analyzed data from a prospectively maintained database of patients who had undergone resection of their gastric cancer at our institution. Patients with T1N0 or M1 lesions, recurrent disease, and mortality within 90 days were excluded. Survival was compared between patients with and without POC in the UpSurg and PreT groups. Cox regression analyses were used to examine factors associated with overall survival (OS) and disease-free survival (DFS).

RESULTS

A total of 421 patients underwent resection of gastric cancer: 30% underwent upfront surgery, and 51% had a POC. Among patients who had POCs, 71% were infectious and 53% were Clavien-Dindo grade III or IV. UpSurg patients with a POC had shorter OS (5-year, 47 vs. 85%; p < 0.001) and DFS (5-year, 46 vs. 76%; p < 0.001) than those without a POC. In contrast, there was no difference in OS (5-year, 57 vs. 63%; p = 0.77) and DFS (5-year, 52 vs. 52%; p = 0.52) between PreT patients with and without POC. Multivariable Cox regression model demonstrated that a POC in UpSurg patients had significant impact on DFS (2.6 [95% confidence interval (CI) 1.48-4.74]), whereas it did not in PreT patients (0.9 [95% CI 0.70-1.33]).

CONCLUSIONS

The use of preoperative therapy negated the impact of POCs on OS and DFS in patients undergoing resection for gastric cancer.

Gastric cancer in Alaska Native people: A cancer health disparity

AIM

To evaluate recent trends in gastric cancer incidence, response to treatment, and overall survival among Alaska Native (AN) people.

METHODS

A retrospective analysis of the Alaska Native Medical Center patient database was performed. Patient history, clinical, pathological, response to treatment and patient outcomes were collected from one-hundred and thirty-two AN gastric cancer patients. The Surveillance, Epidemiology and End Result database 18 was used to collect comparison United States non-Hispanic White (NHW) and AN gastric cancer patient data between 2006-2014.

RESULTS

AN gastric cancer patients have a higher incidence rate, a poorer overall survival, and are diagnosed at a significantly younger age compared to NHW patients. AN patients differ from NHW patients in greater prevalence of non-cardia, diffuse subtype, and signet ring cell carcinomas. AN females were more likely to be diagnosed with later stage cancer, stage IV, compared to AN males. Diminished overall survival was observed among AN patients with increasing stage, O+ blood type, < 15 lymph nodes examined at resection, and no treatment. This study is the first report detailing the clinicopathologic features of gastric cancer in AN people with outcome data.

CONCLUSION

Our findings confirm the importance of early detection, treatment, and surgical resection for optimizing AN patient outcomes. Further research on early detection markers are warranted.

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.

Comparison of DWI and 18F-FDG PET/CT for assessing preoperative N-staging in gastric cancer: evidence from a meta-analysis

The diagnostic values of diffusion weighted imaging (DWI) and ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) for N-staging of gastric cancer (GC) were identified and compared. After a systematic search to identify relevant articles, meta-analysis was used to summarize the sensitivities, specificities, and areas under curves (AUCs) for DWI and PET/CT. To better understand the diagnostic utility of DWI and PET/CT for N-staging, the performance of multi-detector computed tomography (MDCT) was used as a reference. Fifteen studies were analyzed. The pooled sensitivity, specificity, and AUC with 95% confidence intervals of DWI were 0.79 (0.73–0.85), 0.69 (0.61–0.77), and 0.81 (0.77–0.84), respectively. For PET/CT, the corresponding values were 0.52 (0.39–0.64), 0.88 (0.61–0.97), and 0.66 (0.62–0.70), respectively. Comparison of the two techniques revealed DWI had higher sensitivity and AUC, but no difference in specificity. DWI exhibited higher sensitivity but lower specificity than MDCT, and ¹⁸F-FDG PET/CT had lower sensitivity and equivalent specificity. Overall, DWI performed better than ¹⁸F-FDG PET/CT for preoperative N-staging in GC. When the efficacy of MDCT was taken as a reference, DWI represented a complementary imaging technique, while ¹⁸F-FDG PET/CT had limited utility for preoperative N-staging.

Comparative effectiveness of adjuvant chemoradiotherapy after gastrectomy among older patients with gastric adenocarcinoma: a SEER-Medicare study

BACKGROUND

Since the INT-0116 trial reported a survival advantage, postoperative chemoradiotherapy (CRT) has been a care standard for US patients in whom gastric adenocarcinoma has been diagnosed. We sought to estimate the association between treatment and survival among the older US Medicare population.

METHODS

This is a retrospective cohort study of Medicare beneficiaries aged 65-79 years with stage IB-III gastric adenocarcinoma diagnosed between 2002 and 2009 in a Surveillance, Epidemiology, and End Results region. Patients were categorized on the basis of treatment: (1) gastrectomy only and (2) gastrectomy plus adjuvant CRT. We examined factors associated with receipt of adjuvant CRT, including stage at diagnosis, comorbidity, and tumor subtype. Overall survival was measured from 90 days after gastrectomy until death or the censoring date of December 31, 2010.

RESULTS

Of the 1519 patients who underwent gastrectomy, 41.7% received adjuvant CRT. Factors associated with adjuvant CRT included age younger than 75 years at cancer diagnosis and stage II or stage III cancer. The median overall survival from the time of gastrectomy was 25.1 months (interquartile range 43.7 months) for gastrectomy only and 26.9 months (interquartile range 40.9 months) for adjuvant CRT. Multivariable and propensity-score-stratified models demonstrated a survival benefit associated with adjuvant CRT [hazard ratio (HR) 0.58; 95% confidence interval (CI) 0.50-0.67], although the magnitude was greater for stage II tumors (HR 0.50; 95% CI 0.39-0.61) and stage III tumors (HR 0.58; 95% CI 0.45-0.73) than for stage IB tumors (HR 1.02; 95% CI 0.71-1.45).

CONCLUSIONS

Adjuvant CRT, in conjunction with gastrectomy, was associated with a survival benefit among older patients with stage II or stage III tumors.

Impact of c-erbB-2 protein on 5-year survival rate of gastric cancer patients after surgery: a cohort study and meta-analysis

OBJECTIVE

To explore the association of c-erbB-2 protein expression with clinicopathological characteristics and prognosis of gastric cancer (GC) after surgery.

METHODS

A total of 133 patients undergoing surgical resection for GC between March 2006 and January 2009 in the Second Affiliated Hospital of Wenzhou Medical University were included in this study. c-erbB-2 protein expression was determined by immunohistochemistry. Afterwards, a meta-analysis was performed to further confirm the association between c-erbB-2 protein expression and GC by employing stringent inclusion and exclusion criteria. All data analyses were conducted with STATA 12.0 and SPSS 19.0.

RESULTS

There was no significant difference in c-erbB-2 expression among patients with various parameters including age, gender and histological types (all p>0.05). Among 133 GC patients, 32 patients presented c-erbB-2-positive expression and 101 presented c-erbB-2-negative expression (24.1% vs. 75.9%). The c-erbB-2-positive expression rate was significantly higher in GC tissues of patients with lymph node metastasis than those without. Similarly, a significant increase in c-erbB-2 expression was observed in well/moderately differentiated GC tissues compared with poorly differentiated GC. Patients with negative c-erbB-2 expression had a higher 5-year survival rate than those with positive c-erbB-2 expression, which was consistent with the results of the meta-analysis (OR = 0.54, 95% CI 0.37-0.80, p = 0.002).

CONCLUSIONS

Our study demonstrated that high expression of c-erbB-2 protein was strongly associated with lymph node metastasis, histological differentiation and 5-year survival rate in GC patients after surgery.

Patterns of Care for Radiotherapy in the Neoadjuvant and Adjuvant Treatment of Gastric Cancer: A Twelve-Year Nationwide Cohort Study in Korea

Purpose

Although Korea has the highest incidence of gastric cancer worldwide and D2-lymphadenectomies are routinely performed, radiotherapy (RT) practice patterns have not been well studied. Therefore, we examined RT usage trends for neoadjuvant/adjuvant patients and identified factors associated with RT. We also examined survival benefits and net medical cost advantages of adding RT.

Materials and Methods

Patients diagnosed with gastric cancer who underwent gastrectomy from 2002-2013 were identified using National Health Insurance Service-National Sample Cohort.

Results

Annually, 30.9 cases per 100,000 population in crude rate underwent gastrectomy in 230 hospitals and 49.8% received neoadjuvant/adjuvant therapy in 182 hospitals. For neoadjuvant/adjuvant patients, postoperative chemo-RT was administered in 4% of cases in 26 hospitals. No significant trends regarding treatment type were observed over time. Having undergone RT was inversely associated with being ≥ 60 years old and having a low income. Having undergone RT was positively related to having a Charlson comorbidity index ≥ 4, hospital location and hospital volume (≥ 2,000 beds). Significant portions of patients treated with RT in this nation (52%) were concentrated in one large-volume hospital. Use of RT linked to increased cost of primary treatment, yet not to reduced overall medical expense. RT did not influence both on overall and disease-specific survivals after adjusting for potential confounders (p > 0.05).

Conclusion

RT was uncommonly utilized as adjuvant or neoadjuvant treatment by physicians in Korea. Despite intrinsic drawback in this data, we did not find either survival benefit or net medical cost advantage by adding RT in adjuvant treatment.

Recent insights in the therapeutic management of patients with gastric cancer

Gastric cancer remains frequent and one of the most lethal malignancies worldwide. In this article, we aimed to comprehensively review recent insights in the therapeutic management of gastric cancer, with focus on the surgical and perioperative management of resectable forms, and the latest advances regarding advanced diseases. Surgical improvements comprise the use of laparoscopic surgery including staging laparoscopy, a better definition of nodal dissection, and the development of hyperthermic intraperitoneal chemotherapy. The best individualized perioperative management should be assessed before curative-intent surgery for all patients and can consists in perioperative chemotherapy, adjuvant chemo-radiation therapy or adjuvant chemotherapy alone. The optimal timing and sequence of chemotherapy and radiation therapy with respect to surgery should be further explored. Patients with advanced gastric cancer have a poor prognosis. Nevertheless, they can benefit from doublet or triplet chemotherapy combination, including trastuzumab in HER2-positive patients. Upon progression, second-line therapy can be considered in patients with good performance status. Although anti-HER2 (trastuzumab) and anti-VEGFR (ramucirumab) may yield survival benefit, anti-EGFR and anti-HGFR therapies have failed to improve outcomes. Nevertheless, combination regimens containing cytotoxic drugs and targeted therapies should be further evaluated; keeping in mind that gastric cancer biology is different between Asia and the Western countries.

Capecitabine plus paclitaxel induction treatment in gastric cancer patients with liver metastasis: a prospective, uncontrolled, open-label Phase II clinical study

AIM

To determine the overall survival rate, radical resection rate, objective response rate and safety of capecitabine plus paclitaxel induction chemotherapy in gastric cancer patients with liver metastases.

PATIENTS & METHODS

A total of 30 patients (median age: 59.5 years) diagnosed as gastric adenocarcinoma with liver metastasis received ≥3 cycles of capecitabine and paclitaxel therapy followed by radical resection 4-6 weeks after termination of chemotherapy.

RESULTS

The median survival time was 11.4 months, and the objective response rate was 53.3%. The radical resection rate was 23.3% (95% CI: 9.9-42.3). Major toxicities included grade 3 neutropenia (10.0%) and grade 3 diarrhea (3.3%).

CONCLUSION

Capecitabine plus paclitaxel chemotherapy may be effective and safe to improve overall survival and the resection rate of gastric cancer patients with liver metastases. ClinicalTrials.gov identifier: NCT0116704.

Clinical significance and prognostic impact of the total diameter of enlarged lymph nodes on preoperative multidetector computed tomography in patients with gastric cancer

BACKGROUND AND AIM

This study was designed to evaluate the clinical significance and prognostic impact of the total diameter of enlarged lymph nodes (TDL) on preoperative multidetector computed tomography (MDCT) in gastric cancer (GC).

METHODS

Of a total of 480 GC patients between 2005 and 2009, 70 patients with a preoperative diagnosis of nodal metastasis on MDCT were included in this study. All regional lymph nodes showing metastatic involvement were preoperatively counted and measured.

RESULTS

The TDL was calculated, and using a receiver operating characteristic curve, a cutoff value of 45 mm in the two groups of large TDL (LTDL) and small TDL was found to be appropriate for TDL. No significant differences were observed in clinicopathological features, except for tumor recurrence, between the two groups. Univariate survival analysis revealed that patients with LTDL had a worse prognosis as well as an upper tumor location, deeper tumor depth, and further advanced pathological stage. Multivariable prognostic analysis identified LTDL as an independent worse prognostic factor (P = 0.0128).

CONCLUSIONS

GC patients with the total nodal diameter measuring 45 mm or more on MDCT have a worse prognosis. GC patients with the novel surrogate indicator of worse prognosis for a preoperative imaging diagnosis may have need of multimodal treatment to improve the survival.

Both GLUT-1 and GLUT-14 are Independent Prognostic Factors in Gastric Adenocarcinoma

BACKGROUND

The role of glucose transporter 14 (GLUT-14/SLC2A14) in tumor biology is entirely unknown, and the significance of hypoxia inducible factor 1-alpha (HIF1-α) for gastric adenocarcinoma is controversial. The impact of GLUT-1/SLC2A1 has never been confirmed in a Caucasian cohort.

METHODS

Between 1996 and 2007, 124 patients underwent gastrectomy for gastric adenocarcinoma. Tumor sections were incubated with GLUT-1, GLUT-14, and HIF1-α antibodies. Expression was analyzed for correlations with histopathology, marker coexpression, and patient survival by uni- and multivariate analyses.

RESULTS

Expressions of GLUT-1, GLUT-14, and HIF1-α were detectable in 50, 77.4, and 27.1 %, respectively. Expression of GLUT-1 was associated with pT-category (p = 0.019), pN-category (p = 0.019), tubular (WHO, p = 0.008), and intestinal (Lauren classification; p = 0.002) histologic subtypes. Expression of GLUT-14 was correlated with pT category (p = 0.043), whereas HIF1-α did not show any correlation with histopathology or survival. The median survival period was 14 months (95 % confidence interval [CI] 9.2-18.8 months) for GLUT-1-positive patients and 55 months (95 % CI 25.8-84.2; p = 0.01) for GLUT-1-negative patients. An inferior prognosis also was seen for GLUT-14-positive cases compared with GLUT-14-negative cases (p = 0.004). Thus, worst survival was seen with both GLUT-1- and GLUT-14-positive expression followed by single-positive and then double-negative cases (p = 0.004). In multivariate analysis including International Union Against Cancer (UICC) stages, R category, Lauren classification, surgery alone versus neoadjuvant/perioperative chemotherapy, and marker expression as covariates, GLUT-1 (p = 0.011) and GLUT-14 (p = 0.025) kept their prognostic independence.

CONCLUSIONS

The study findings suggest that detection of GLUT-1 and GLUT-14 is of high prognostic value. It gives additional information to UICC stages and identifies patients with inferior prognosis. If confirmed in prospective studies, these markers need to be considered for future classification systems.

Postoperative chemoradiotherapy vs. preoperative chemoradiotherapy for locally advanced (operable) gastric cancer: clarifying the role and technique of radiotherapy

BACKGROUND

Worldwide, almost one million new cases of stomach cancer were diagnosed in 2012, making it the fifth most common cancer, and the third leading cause of cancer deaths. The current tumor node metastasis (TNM) staging system represents a consensus between the East and the West, and will serve as a strong foundation upon which to build future evidence. In this review article, we first discuss the definition and optimal surgery for locally advanced gastric cancer, followed by the general principles when considering a pre vs. postoperative radiotherapy (RT) strategy. We then provide a synthesis of the existing randomized trial evidence in an attempt clarify the role of pre and postoperative RT in the management of locally advanced gastric cancer.

METHODS

A Medline search 1966-Jun 2014 was undertaken. Randomized trials including patients with locally advanced gastric cancer (using established definitions), comparing RT [with or without chemotherapy (CT)], with surgery alone or other treatment modalities were included. Systematic reviews and evidence based practice guidelines that include this body of primary studies were preferentially discussed. Medline, Cochrane Library, Clinicaltrial.gov, Guidelines Clearinghouse were searched.

RESULTS

Sixteen randomized trials, three systematic reviews and one practice guideline were included as the evidence base. In this group of studies, two reports compared postoperative chemoradiotherapy (CRT) with surgery alone. Driven predominantly by INT0116, they established the role of postoperative CRT to provide a survival benefit in a patient group that underwent surgery with predominantly D0-1 dissections. Preoperative RT (four studies) showed promise for survival benefit but the risks of bias in these trials were high. Postoperative CRT compared with CT alone (eight trials) showed no survival benefit with the addition of radiation although some evidence of activity can be observed with improved local regional control.

CONCLUSIONS AND FUTURE DIRECTIONS

Technical expertise to enable the delivery of high quality RT to complex target volumes as is required in gastric cancer, and surgical standards to ensure the delivery of high quality surgery, have matured in recent years. Six trials with large sample sizes are currently ongoing to better define the role of preoperative CRT (two studies) and postoperative CRT (four studies), when used in conjunction with high quality surgery and RT, and contemporary CT regimens. The moderate likelihood of locoregional recurrences and the favorable therapeutic ratio with using RT preoperatively in other settings, provide optimism that preoperative CRT would have a pivotal role to play in locally advanced gastric cancer. Active accrual into ongoing trials is strongly encouraged.

Clinical utility of perioperative staging laparoscopy for advanced gastric cancer

BACKGROUND

Perioperative staging laparoscopy is a useful tool for the detection of occult peritoneal metastases in gastrointestinal cancers. This retrospective study aimed to determine the clinical value of staging laparoscopy for advanced or recurrent gastric cancer.

METHODS

A total of 178 patients with advanced or recurred gastric cancer who underwent perioperative staging laparoscopy were enrolled. In the absence of peritoneal deposits (P1) and positive peritoneal cytology (CY1), gastrectomy with lymph node dissection was indicated with curative intent. If P1 or CY1 was detected intraoperatively, patients received intensive chemotherapy and laparoscopic surgical intervention.

RESULTS

Curative gastrectomy was performed in 104 patients after confirmation of P0 and CY0 status. P1 or CY1 was detected for the first time in 23 (15%) patients. A total of 13 patients were converted from gastrectomy to intensive chemotherapy after detection of P1 or CY1. Additional laparoscopic interventions included insertion of intraperitoneal reservoir port in 54 patients, insertion of a metallic stent in five, ileostomy for colon stricture in six, jejunostomy in 19, and gastrojejunostomy in 16. Of eight patients treated with intensive chemotherapy who underwent R0 gastrectomy after second-look laparoscopy, five are currently free from recurrence of gastric cancer for 25.5 months.

CONCLUSIONS

Occult peritoneal dissemination was detected in about 14% in patients with tumors deeper than T2. Moreover, additional laparoscopic interventions can be utilized for P1 or CY1 patients. The excellent surgical outcomes of R0 gastrectomy after chemotherapy and second-look laparoscopy indicate that confirmation of P0 and CY0 status by staging laparoscopy is of value to determine treatment strategy in patients with advanced gastric cancer.

Adjuvant therapy for gastric cancer: Current and future directions

The management of gastric cancer continues to evolve. Whilst surgery alone is effective when tumours present early, a large proportion of patients are diagnosed with loco-regionally advanced disease, resulting in high loco-regional and distant relapse rates, with subsequent poor survival. Early attempts at improving outcomes following resection were disappointing; however, randomized trials have now established either post-operative chemoradiotherapy (INT0116) or peri-operative chemotherapy as standard adjuvant therapies in the Western world. There remain, however, significant differences in the approach to management between the West and East. In Asia, where there is the highest incidence of gastric cancer, extended resection followed by adjuvant chemotherapy represents the standard of care. This review discusses current standard adjuvant therapy in gastric adenocarcinoma, as well as recent and ongoing trials investigating novel (neo)adjuvant approaches, which hope to build on the successes of previous studies.

Postoperative chemo-radiotherapy versus chemotherapy for resected gastric cancer: a systematic review and meta-analysis

INTRODUCTION

This study conducted a systematic review and meta-analysis (direct and indirect) of published randomised controlled trials (RCTs) to compare the effects of postoperative chemo-radiotherapy (ChRT) with chemotherapy (Ch) on overall and disease-free survival (DFS) for patients with resectable gastric cancer.

METHODS

We searched MEDLINE and CENTRAL from the date of inception and annual meeting proceedings of American Society of Clinical Oncology and American Society for Radiation Oncology from 1999 to November 2012 for RCTs comparing postoperative ChRT with Ch, postoperative ChRT with surgery alone and postoperative Ch with surgery alone. The primary outcome was overall survival (OS); secondary outcomes included DFS and toxicity. Hazard ratios (HRs), confidence intervals (CIs) and P values (P) were estimated with fixed effects models using Revman 5.1.

RESULTS

We found six trials comparing postoperative ChRT with Ch (n = 1171). Meta-analysis of direct comparison trials showed that postoperative ChRT significantly improved both OS (HR 0.80, 95% CI 0.65-0.98, P = 0.03) and DFS (HR 0.76, 95% CI 0.63-0.91, P = 0.003) when compared with Ch. There were no significant differences in toxicity between the two groups.

CONCLUSIONS

This study suggests a survival benefit of postoperative ChRT over Ch in patients with resected gastric cancer.

Role of (chemo)-radiotherapy in resectable gastric cancer

The prognosis of patients with locally advanced gastric cancer remains poor, despite radical surgical resection. Adjuvant therapy has been shown to improve survival and, in Western countries, is delivered either postoperatively (chemoradiotherapy) or perioperatively (chemotherapy). Debate continues as to which of these represents the optimal strategy. High-dose gastric irradiation comes at the expense of significant toxicity, and increasing efforts have focused on attempts to reduce toxicity and normal tissue doses. The development of advancing radiotherapy technologies now allows improved target delineation and coverage. However, gastric irradiation remains technically challenging and requires an understanding of postoperative surgical anatomy, patterns of failure and lymph node drainage, as well as an appreciation of the uncertainties around organ motion and filling. Ongoing trials are examining the optimal strategy in which to incorporate (chemo)-radiotherapy, as well as the addition of targeted therapies, in gastric cancer. This overview discusses the current role and evidence for (chemo)-radiotherapy, as well as the technical challenges encountered in the radiotherapeutic management of resectable gastric cancer.

Relationships between abnormal MMP2 expression and prognosis in gastric cancer: a meta-analysis of cohort studies

We carried out this current meta-analysis of relevant cohort studies in an attempt to investigate the relationships between abnormal matrix metalloproteinases-2 (MMP2) expression and gastric cancer (GC) prognosis. A range of electronic databases were searched for relevant articles without any language restrictions: Web of Science (1945-2013), the Cochrane Library Database (Issue 12, 2013), PubMed (1966-2013), EMBASE (1980-2013), CINAHL (1982-2013), and the Chinese Biomedical Database (CBM) (1982-2013). Meta-analysis was conducted using the STATA 12.0 software. Crude hazard ratios (HRs), with 95% confidence intervals (95% CIs), were calculated. Ten clinical cohort studies with a total of 1669 GC patients were included in this meta-analysis. The results of our meta-analysis suggested that MMP2-positive patients display a shorter overall survival (OS) than MMP2-negative patients (HR=1.31, 95% CI=0.98-1.63, p<0.001). Subgroup analysis based on ethnicity revealed that abnormal MMP2 expression was associated with significantly worse OS in patients with GC among both Caucasian and Asian populations (all p<0.05). Our meta-analysis indicated that abnormal MMP2 expression may be strongly correlated with poor prognosis in patients with GC. Thus, MMP2 expression may serve as an independent prognostic factor for GC.

Efficacy of SOX regimen versus XELOX regimen in concurrent chemoradiotherapy for postoperative recurrent gastric carcinoma

AIM: To evaluate the efficacy and safety of SOX regimen (S-1 + L-OHP) versus XELOX regimen (capecitabine + L-OHP) in concurrent chemoradiotherapy for postoperative recurrent gastric carcinoma.

METHODS: Sixty-six elderly patients with postoperative recurrent gastric cancer were randomly divided into two groups: an SOX group (n = 34) and a XELOX group (n = 32). The SOX group received oral S-1 (< 1.25 m², 40 mg; 1.25-1.5 m2, 50 mg; > 1.5 m², 60 mg), twice daily, d1-14; L-OHP (85 mg/m², d1); and three-dimensional conformal radiation (1.8 Gy/d, 5 d/wk and the total dose was 45 Gy). The XELOX group was treated with capecitabine (2000 mg/m², separated to twice, d1-14), plus the same regimen of radiation and L-OHP as those in the SOX group. Each cycle lasted three weeks. The efficacy and toxicity were evaluated after two cycles of treatment.

RESULTS: The efficacy and toxicity could be evaluated in 66 cases. There were no significant differences in the overall response rate (55.9% vs 46.9%), median time to progression (TTP) (6.3 mo vs 5.8 mo) or median overall survival (OS) (12.8 mo vs 12.2 mo) (P > 0.05) between the two groups. The most common toxicities in the two groups were neutropenia, thrombopenia, nausea, vomiting and diarrhea, all of which could be tolerated. However, the incidence of hand-foot syndrome was significantly higher in the SOX group than in the XELOX group (P < 0.05).

CONCLUSION: The efficacy of chemoradiotherapy based on the SOX regimen for postoperative recurrent gastric carcinoma is better than that of concurrent chemoradiotherapy based on the XELOX regimen in terms of well-tolerated toxicity.

Diagnosis and evaluation of gastric cancer by positron emission tomography

Gastric cancer is the second leading cause of cancer mortality worldwide. The diagnosis of gastric cancer has been significantly improved with the broad availability of gastrointestinal endoscopy. Effective technologies for accurate staging and quantitative evaluation are still in demand to merit reasonable treatment and better prognosis for the patients presented with advanced disease. Preoperative staging using conventional imaging tools, such as computed tomography (CT) and endoscopic ultrasonography, is inadequate. Positron emission tomography (PET), using (18)F-fluorodeoxyglucose (FDG) as a tracer and integrating CT for anatomic localization, holds a promise to detect unsuspected metastasis and has been extensively used in a variety of malignancies. However, the value of FDG PET/CT in diagnosis and evaluation of gastric cancer is still controversial. This article reviews the current literature in diagnosis, staging, response evaluation, and relapse monitoring of gastric cancer, and discusses the current understanding, improvement, and future prospects in this area.

Role of imaging in predicting response to neoadjuvant chemotherapy in gastric cancer

With the proven overall benefit of neoadjuvant chemotherapy in patients with locally advanced gastric cancer, there has come a need to discriminate responders from non-responders. In this article, the current role of anatomical and molecular imaging in the prediction of response to neoadjuvant therapy in gastric cancer is outlined and future prospects are discussed.

Chemoradiation therapy versus chemotherapy alone for gastric cancer after R0 surgical resection: a meta-analysis of randomized trials

OBJECTIVE

Current national guidelines include category 1 recommendations for perioperative chemotherapy or adjuvant chemoradiation with surgical resection for patients with stage IB-IIIB gastric cancer. We conducted a meta-analysis of randomized trials in which chemotherapy was prospectively tested against chemoradiation with surgical resection.

METHODS

We electronically searched PubMed and EMBASE for randomized, controlled clinical trials involving patients with gastric adenocarcinoma, status post-R0 resection. The interventions compared were adjuvant chemotherapy versus chemoradiation, with any chemotherapy regimen. The primary outcomes of interest were disease-free survival and overall survival. The Mantel-Haenszel random-effects model was used to calculate effect sizes.

RESULTS

Six trials that included 1,171 patients were evaluated; 599 were randomized to adjuvant chemoradiation and 572 to chemotherapy alone. Chemoradiation was associated with a significant increase in disease-free survival (odds ratio 1.48, 95% confidence interval 1.08-2.03) when compared to chemotherapy alone. However, there was no significant difference in overall survival (odds ratio 1.27, 95% confidence interval 0.95-1.71). Five trials found no statistically significant differences in toxicities between the two groups.

CONCLUSION

In patients with gastric cancer status post-R0 resection, adjuvant chemoradiation was associated with higher disease-free survival when compared to chemotherapy alone. It remains appropriate to design trials testing new systemic agents with radiotherapy.

Population-based outcome of stage IA-IIA resected gastric adenocarcinoma: who should get adjuvant treatment?

BACKGROUND

The benefit of adjuvant treatment in gastric adenocarcinoma was demonstrated by randomized, controlled trials of patients with locally advanced tumors. Thus, its role for stage IIB-IIIC disease is widely accepted. We aimed to identify patients with stage IA-IIA gastric adenocarcinoma who have a poor prognosis and thus may benefit from adjuvant treatment.

METHODS

Patients with gastric adenocarcinoma who underwent surgical resection with pathological evaluation of ≥15 lymph nodes and had available disease-specific survival (DSS) data were identified from the Surveillance Epidemiology and End Results Registry. Survival differences were evaluated with the log-rank test and Cox multivariate analysis.

RESULTS

Stage and TN grouping strongly predicted DSS (P < 0.001, P < 0.001). Stage IA tumors had an excellent outcome: 91 ± 1.2 % 5-year DSS. The TN groupings of stages IB and IIA had the next best outcomes with 5-year DSS from 66 ± 4.6 % to 81 ± 2.3 %. Older age (P < 0.001), higher grade (P = 0.004), larger tumor size (P < 0.001), and proximal tumor location (P < 0.001) were independent predictors of worse DSS in stage IB-IIA tumors. We devised a risk stratification scheme for stage IB-IIA tumors where 1 point was assigned for age >60 years, tumor size >5 cm, proximal tumor location, and grade other than well-differentiated. Five-year DSS was 100 % for patients with 0 points; 86 ± 4.3 %, 1 point; 76 ± 3 %, 2 points; 72 ± 2.8 %, 3 points; and 48 ± 4.9 %, 4 points (P < 0.001).

CONCLUSIONS

Patients with stage IB-IIA gastric adenocarcinoma and ≥2 adverse features (age >60 years, tumor size >5 cm, proximal location, and high-grade) have 5-year DSS ≤76 %. Adjuvant therapy may be warranted for these patients.

Adjuvant chemoradiotherapy after d2-lymphadenectomy for gastric cancer: the role of n-ratio in patient selection. results of a single cancer center

Background

Adjuvant chemoradiotherapy is part of a multimodality treatment approach in order to improve survival outcomes after surgery for gastric cancer. The aims of this study are to describe the results of gastrectomy and adjuvant chemoradiotherapy in patients treated in a single institution, and to identify prognostic factors that could determine which individuals would benefit from this treatment.

Methods

This retrospective study included patients with pathologically confirmed gastric adenocarcinoma who underwent surgical treatment with curative intent in a single cancer center in Brazil, between 1998 and 2008. Among 327 patients treated in this period, 142 were selected. Exclusion criteria were distant metastatic disease (M1), T1N0 tumors, different multimodality treatments and tumors of the gastric stump. Another 10 individuals were lost to follow-up and there were 3 postoperative deaths. The role of several clinical and pathological variables as prognostic factors was determined.

Results

D2-lymphadenectomy was performed in 90.8% of the patients, who had 5-year overall and disease-free survival of 58.9% and 55.7%. The interaction of N-category and N-ratio, extended resection and perineural invasion were independent prognostic factors for overall and disease-free survival. Adjuvant chemoradiotherapy was not associated with a significant improvement in survival. Patients with node-positive disease had improved survival with adjuvant chemoradiotherapy, especially when we grouped patients with N1 and N2 tumors and a higher N-ratio. These individuals had worse disease-free (30.3% vs. 48.9%) and overall survival (30.9% vs. 71.4%).

Conclusion

N-category and N-ratio interaction, perineural invasion and extended resections were prognostic factors for survival in gastric cancer patients treated with D2-lymphadenectomy, but adjuvant chemoradiotherapy was not. There may be some benefit with this treatment in patients with node-positive disease and higher N-ratio.

Quality Research in Radiation Oncology analysis of clinical performance measures in the management of gastric cancer

BACKGROUND

The specific aim was to determine national patterns of radiation therapy (RT) practice in patients treated for stage IB-IV (nonmetastatic) gastric cancer (GC).

METHODS AND MATERIALS

A national process survey of randomly selected US RT facilities was conducted which retrospectively assessed demographics, staging, geographic region, practice setting, and treatment by using on-site record review of eligible GC cases treated from 2005 to 2007. Three clinical performance measures (CPMs), (1) use of computed tomography (CT)-based treatment planning; (2) use of dose volume histograms (DVHs) to evaluate RT dose to the kidneys and liver; and (3) completion of RT within the prescribed time frame; and emerging quality indicators, (i) use of intensity modulated RT (IMRT); (ii) use of image-guided tools (IGRT) other than CT for RT target delineation; and (iii) use of preoperative RT, were assessed.

RESULTS

CPMs were computed for 250 eligible patients at 45 institutions (median age, 62 years; 66% male; 60% Caucasian). Using 2000 American Joint Committee on Cancer criteria, 13% of patients were stage I, 29% were stage II, 32% were stage IIIA, 10% were stage IIIB, and 12% were stage IV. Most patients (43%) were treated at academic centers, 32% were treated at large nonacademic centers, and 25% were treated at small to medium sized facilities. Almost all patients (99.5%) underwent CT-based planning, and 75% had DVHs to evaluate normal tissue doses to the kidneys and liver. Seventy percent of patients completed RT within the prescribed time frame. IMRT and IGRT were used in 22% and 17% of patients, respectively. IGRT techniques included positron emission tomography (n=20), magnetic resonance imaging (n=1), respiratory gating and 4-dimensional CT (n=22), and on-board imaging (n=10). Nineteen percent of patients received preoperative RT.

CONCLUSIONS

This analysis of radiation practice patterns for treating nonmetastatic GC indicates widespread adoption of CT-based planning with use of DVH to evaluate normal tissue doses. Most patients completed adjuvant RT in the prescribed time frame. IMRT and IGRT were not routinely incorporated into clinical practice during the 2005-2007 period. These data will be a benchmark for future Quality Research in Radiation Oncology GC surveys.

Gastrointestinal lymphomas: Morphology, immunophenotype and molecular features

Primary gastrointestinal lymphoma comprises 10-15% of all non-Hodgkin lymphomas and encompasses 30-40% of the total extranodal lymphomas. Approximately 60-75% of cases occur in the stomach, and then the small bowel, ileum, cecum, colon and rectum. Lymphoid neoplasms may consist of mature B, T and less commonly extranodal NK/T cells. Of these, the two most frequently encountered histologic subtypes are extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma), where Helicobacter pylori infection is implicated in a number of cases, and diffuse large B cell lymphoma. Several B cell lymphomas are associated with chromosomal aberrations. Enteropathy-associated T cell lymphoma, type I in particular, usually arises in a background of celiac disease. T cell gene rearrangement confirms clonality. NK/T cell neoplasms are invariably associated with Epstein-Barr virus infection and are often aggressive; thus, differentiation from a benign NK-cell enteropathy is paramount. Although incidence of other hematopoietic malignancies in the gastrointestinal tract such as plasma cell myeloma associated with amyloidosis, plasmablastic lymphoma, Hodgkin disease, histiocytic sarcoma and mast cell sarcoma is extremely rare, these entities have been documented, with the latter two demonstrating aggressive clinical behavior. Endoscopic ultrasonography is an important adjunct in disease staging and follow-up. Conservative antibiotic treatment of stage I MALT lymphomas with associated Helicobacter pylori infection achieves good clinical outcome with high remission rate. Chemotherapy, radiation and rarely surgery are reserved for advanced diseases or cases resistant to conservative therapy and those not associated with Helicobacter pylori infection.