Changing gastric cancer treatment in the United States and the pursuit of quality

A global and physical mechanism of gastric cancer formation and progression

Gastric cancer is regarded as a major health issue for human being nowadays. The Helicobacter pylori (H. pylori) infection has been found to accelerate the development of gastritis and gastric cancer. Significant efforts have been made towards the understanding of the biology of gastric cancer on both genetic and epigenetic levels. However the physical mechanism behind the gastric cancer formation is still elusive. In this study, we constructed a model for investigating gastric cancer formation by explored the gastric cancer landscape and the flow flux. We uncovered three stable state attractors on the landscape: normal, gastritis and gastric cancer. The definition of each attractor is based on the biological function and gene expression levels. The global stabilities and the switching processes were quantified through the barrier heights and dominant kinetic paths. To investigate the underlying mechanism of the process from normal through the gastritis to the gastric cancer caused by genetic or epigenetic factors, we simulate the oncogenesis of gastric cancer through changes of several gene regulation strengths and H. pylori infection. The simulated results can illustrate the developmental and metastasis process of gastric cancer. Different H. pylori infection degrees accelerating the process from gastritis to gastric cancer can be quantified. Then we applied global sensitivity analysis, one key gene and four key regulations were found. These results are consist with the experimental results and can be used to design the polygenic anti-cancer agents through multiple key genes or regulations. The landscape approach provides a physical and simple strategy for analyzing gastric cancer in a systematic and quantitative way. It also offers new insight into treatment strategy for gastric cancer by adjusting relevant polygenic genes and regulations.

Morbidity and mortality associated with gastrectomy for gastric cancer

BACKGROUND

Surgery alone is often inadequate for advanced-stage gastric cancer. Surgical complications may delay adjuvant therapy. Understanding these complications is needed for multidisciplinary planning.

MATERIAL AND METHODS

The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database was queried for patients who underwent gastrectomy for malignancy (ICD-9 code 151.x) from 2005 to 2010. Thirty-day mortality and morbidity were evaluated.

RESULTS

Overall, 2,580 patients underwent gastrectomy for malignancy, divided as total gastrectomy 999 (38.7 %) and partial gastrectomy 1,581 (61.3 %). Overall, serious morbidity occurred in 23.6 %, and the 30-day mortality was 4.1 %. Patients receiving a total gastrectomy were younger and healthier than those receiving a partial gastrectomy for the following measured criteria: age, diabetes, chronic obstructive pulmonary disease and hypertension. Serious morbidity and mortality were significantly higher in the total gastrectomy group than the partial gastrectomy group (29.3 vs. 19.9 %, p < 0.001; and 5.4 vs. 3.4 %, p < 0.015, respectively). The inclusion of additional procedures increased the risk of mortality for the following: splenectomy (odds ratio [OR] 2.8; p < 0.001), pancreatectomy (OR 3.5; p = 0.001), colectomy (OR 3.6; p < 0.001), enterectomy (OR 2.7; p = 0.030), esophagectomy (OR 3.5; p = 0.035). Abdominal lymphadenectomy was not associated with increased morbidity (OR 1.1; p = 0.41); rather, it was associated with decreased mortality (OR 0.468; p = 0.028).

CONCLUSIONS

Gastrectomy for cancer as currently practiced carries significant morbidity and mortality. Inclusion of additional major procedures increases these risks. The addition of lymphadenectomy was not associated with increased morbidity or mortality. Strategies are needed to optimize surgical outcomes to ensure delivery of multimodality therapy for advanced-stage disease.

Optimal management of gastric cancer: results from an international RAND/UCLA expert panel

OBJECTIVE

Defining processes of care, which are appropriate and necessary for management of gastric cancer (GC), is an important step toward improving outcomes.

METHODS

Using a RAND/UCLA Appropriateness Method, an international multidisciplinary expert panel created 22 statements reflecting optimal management. All statements were scored for appropriateness and necessity.

RESULTS

The following tenets were scored appropriate and necessary: (1) preoperative staging by computed tomography of abdomen/pelvis; (2) positron-emission tomographic scans not routinely indicated; (3) consideration for adjuvant therapy; (4) further clinical trials; (5) multidisciplinary decision making; (6) sufficient support at hospitals; (7) assessment of 16 or more lymph nodes (LNs); (8) in metastatic disease, surgery only for palliation of major symptoms; (9) surgeons experienced in GC management; (10) and surgeons experienced in both GC management and advanced laparoscopic surgery for laparoscopic resection. The following were scored appropriate, but of indeterminate necessity: (1) diagnostic laparoscopy before treatment; (2) a multidisciplinary approach to linitis plastica; (3) genetic assessment for diffuse GC and family history, or age less than 45 years; (4) endoscopic removal of select T1aN0 lesions; (5) D2 LN dissection in curative intent cases; (6) D1 LN dissection for early GC or patients with comorbidities; (7) frozen section analysis of margins; (8) nonemergent cases performed in a hospital with a volume of more than 15 resections per year; and (9) by a surgeon with more than 6 resection per year.

CONCLUSIONS

The expert panel has created 22 statements for the perioperative management of GC patients, to provide guidance to clinicians and improve the care received by patients.

Quality of gastric cancer care in designated cancer care hospitals in Japan

OBJECTIVE

To develop a set of process-of-care quality indicators (QIs) that would cover a wide range of gastric cancer care modalities and to examine the current state of the quality of care provided by designated cancer care hospitals in Japan.

DESIGN

A retrospective medical record review.

SETTING

Eighteen designated cancer care hospitals throughout Japan.

PARTICIPANTS

A total of 1685 patients diagnosed with gastric cancer in 2007.

MAIN OUTCOME MEASURES

Provision of care to eligible patients as described in the 29 QIs, which were developed using an adaptation of the RAND/UCLA (University of California, Los Angeles) appropriateness method by a panel of nationally recognized experts in Japan.

RESULTS

Overall, the patients received 68.3% of the care processes recommended by the QIs. While 'deep venous thrombosis prophylaxis before major surgery' was performed for 99% of the cases, 'documentation before endoscopic resection' was completed for only 12% of the cases. The chemotherapy care was less likely to meet the QI standards (61%) than pre-therapeutic care (76%), surgical treatment (66%) and endoscopic resection (71%; overall difference: P < 0.001). A comparison based on the types of care showed that documentation and patient explanation were performed less frequently (60 and 53%, respectively) than were diagnostic and therapeutic processes as recommended in the QIs (85%; overall P < 0.001).

CONCLUSIONS

Although many required care processes were provided, some areas with room for improvement were revealed, especially with respect to chemotherapy, documentation and patient explanation. Continuous efforts to improve the quality and develop a system to monitor this progress would be beneficial in Japan.

Myofibrillogenesis regulator-1 overexpression is associated with poor prognosis of gastric cancer patients

AIM: To investigate the expression of myofibrillogenesis regulator-1 (MR-1) in relation to clinicopathological parameters and postoperative survival in a group of Chinese patients with gastric cancer.

METHODS: In our previous study of human whole-genome gene expression profiling, the differentially expressed genes were detected in the gastric cancer and its adjacent noncancerous mucosa. We found that MR-1 was associated with the location and differentiation of tumors. In this study, MR-1 protein expression was determined by immunohistochemistry in specimens of primary cancer and the adjacent noncancerous tissues from gastric cancer patients. A set of real-time quantitative polymerase chain reaction assays based on the Universal ProbeLibrary-a collection of 165 presynthesized, fluorescence-labeled locked nucleic acid hydrolysis probes-was designed specifically to detect the expression of MR-1 mRNA. The correlation was analyzed between the expression of MR-1 and other tumor characteristics which may influence the prognosis of gastric cancer patients. A retrospective cohort study on the prognosis was carried out and clinical data were collected from medical records.

RESULTS: MR-1 mRNA and protein could be detected in gastric cancer tissues as well as in matched noncancerous tissues. MR-1 was up-regulated at both mRNA (5.459 ± 0.639 vs 1.233 ± 0.238, P < 0.001) and protein levels (34.2% vs 13.2%, P = 0.003) in gastric cancer tissues. Correlation analysis demonstrated that high expression of MR-1 in gastric cancer was significantly correlated with clinical stage (P = 0.034). Kaplan-Meier analysis showed that the postoperative survival of the MR-1 positive group tended to be poorer than that of the MR-1 negative group, and the difference was statistically significant (P = 0.002). Among all the patients with stage I-IV carcinoma, the 5-year survival rates of MR-1 positive and negative groups were 50.40% and 12.70%, respectively, with respective median survival times of 64.27 mo (95%CI: 13.41-115.13) and 16.77 mo (95%CI: 8.80-24.74). Univariate and multivariate analyses were performed to compare the impact of MR-1 expression and other clinicopathological parameters on prognosis. In a univariate analysis on all 70 specimens, 6 factors were found to be significantly associated with the overall survival statistically: including MR-1 expression, depth of invasion, distant metastasis, lymph node metastasis, vascular invasion and the tumor node metastasis (TNM) stage based on the 7th edition of the International Union against Cancer TNM classification. To avoid the influence caused by univariate analysis, the expressions of MR-1 as well as other parameters were examined in multivariate Cox analysis. Clinicopathological variables that might affect the prognosis of gastric cancer patients were analyzed by Cox regression analysis, which showed that MR-1 expression and TNM stage were independent predictors of postoperative survival. The best mathematical multivariate Cox regression model consisted of two factors: MR-1 expression and TNM stage. Our results indicated that MR-1 protein could act as an independent marker for patient overall survival [Hazard ratio (HR): 2.215, P = 0.043].

CONCLUSION: MR-1 is an important variable that can be used to evaluate the outcome, prognosis and targeted therapy of gastric cancer patients.

Decreased expression of RASSF6 is a novel independent prognostic marker of a worse outcome in gastric cancer patients after curative surgery

BACKGROUND

Our previous study observed that the expression of RASSF6, a member of the Ras-association domain family, was down-regulated in gastric cancer cells. The present study further investigated the clinical significance of RASSF6 in gastric cancer.

METHODS

Using real-time PCR, Western blot analysis, tissue microarray (TMA), and immunohistochemical staining, we evaluated RASSF6 mRNA and protein levels in tumor tissues and in the paired adjacent normal mucosa from patients with gastric cancers at different stages.

RESULTS

RASSF6 mRNA and protein levels were decreased in gastric cancer tissues compared with the adjacent normal mucosa. Immunohistochemical detection of RASSF6 in a TMA that contained 264 paired specimens showed that a decreased cytoplasmic RASSF6 expression was significantly associated with the extent of cancer invasion, lymph node metastasis, distant metastasis, tumor histological grade, advanced clinical stage, and Ki-67 proliferative index. Moreover, RASSF6 expression in metastatic lymph nodes was lower than in the paired primary tumors. Patients with RASSF6-negative tumors had extremely higher disease recurrence rates and poorer survival than patients with RASSF6-positive tumors even after radical surgery. Stratification analysis revealed RASSF6 as an independent predictor for tumor recurrence in patients with gastric cancers irrespective of tumor stage.

CONCLUSIONS

RASSF6 might contribute to the progression of gastric carcinogenesis and may function as a novel independent prognostic marker for the prediction of the recurrence of cancer in patients after curative operations.

Surgeons' knowledge of quality indicators for gastric cancer surgery

BACKGROUND

Gastric cancer survival in the West is inferior to that achieved in Asian centers. While differences in tumor biology may play a role, poor quality surgery likely contributes to understaging. We hypothesize that the majority of surgeons performing gastric cancer surgery in North America are unaware of the recommended standards.

METHODS

Using the Ontario College of Physicians and Surgeons registry, surgeons who potentially included gastric cancer surgery in their scope of practice were identified. A questionnaire was mailed to 559; of those, 206 surgeons reported managing gastric cancer. Results were evaluated by chi(2) and logistic regression; P < 0.05 was considered significant.

RESULTS

Eighty-six percent of respondents were male and 53% practiced in an urban nonacademic setting. Forty percent reported operating on two to five cases of gastric cancer per year, and 42% on fewer than two cases per year. One-third of surgeons identified 4 cm or less to be the desired gross proximal margin. Half used frozen section to evaluate margin status. Twenty percent of surgeons were unsure of the number of lymph nodes (LN) needed to accurately stage gastric cancer, and the median number reported by the remainder was 10 (range, 0-30). Only 16 of 206 identified both a proximal margin of 5 cm or less and 15 or more LN as desired targets. Those performing more than five gastric resections per year were more likely to report a D2 resection (P = 0.008).

CONCLUSION

The majority of surgeons operating on gastric cancer in Ontario did not identify recommended quality indicators of gastric cancer surgery. A continuing medical education program should be designed to address this knowledge gap to improve the quality of surgery and patient outcomes.

Expression of vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR) is an independent prognostic indicator of worse outcome in gastric cancer patients

BACKGROUND

Unlike other human tumors, gastric cancer remains a great therapeutic challenge since no standardized postoperative treatment exists. Knowledge of molecular pathways determining the behavior of individual gastric tumors seems to be crucial for therapeutic decisions, and evaluation of vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR) expression might be critical for prognosis, assessment, and identification of patients that could be treated with tailored therapies.

METHODS

VEGF and EGFR determination was performed in 88 gastric cancer samples as well as 25 normal gastric mucosa specimens from non-cancer patients using a commercially available immunohistochemistry kit. In all samples, the correlation of VEGF and EGFR expression was investigated with each other, and with other prognostic indicators in all samples, and, finally, with survival rates in 69 patients undergoing potentially curative surgery.

RESULTS

Forty-eight per cent (42 cases) of gastric cancers expressed VEGF, and 44% (39 cases) stained for EGFR. In curatively treated patients, VEGF and EGFR expression was demonstrated to correlate with worse survival in both univariate and multivariate analyses. Molecular profiling was shown to more accurately estimate the risk of cancer-related death than TNM stage, and, of most interest, to allow sorting out high-risk patients within the same stage.

CONCLUSIONS

These findings provide evidence that contemporary evaluation of VEGF and EGFR expression may be crucial to select gastric cancer patients with poor prognosis who may benefit of tailored treatments.

Self-reported experience and outcomes of care among stomach cancer patients at a median follow-up time of 27 months from diagnosis

GOALS OF WORK

We aimed to identify clinical experiences associated with outcomes of care among stomach cancer patients.

MATERIALS AND METHODS

Four hundred thirty-two patients who had a diagnosis of stage I-III stomach cancer from 2001 through 2002 from two hospitals in South Korea responded to a survey questionnaire including sociodemographic and clinical data, information about care experiences, satisfaction with care, and quality of life (QOL).

MAIN RESULTS

Involvement in decision making [adjusted odds ratio (aOR) = 1.81; 95% confidence interval (CI), 1.13 to 2.89] and reflection of patients' opinions in treatment decisions (aOR = 2.54; 95% CI, 1.65 to 3.93) were associated with decision satisfaction. The factors associated with willingness to choose the same treatment over again were involvement in decision making (aOR = 2.37; 95% CI, 1.53 to 3.68) and no treatment toxicity (aOR = 0.50; 95% CI, 0.29 to 0.87). Involvement in decision making, reflection of patients' opinions in treatment decisions, and treatment toxicity were associated with some functioning subscales of QOL (p < 0.05). Regular follow-up, however, was associated with poor social functioning.

CONCLUSIONS

Quality improvement efforts for stomach cancer patients should focus not only on the quality of primary tumor therapy but also on how patients experience their care, such as patient-centered decision making, experience of treatment toxicity, and regular follow-up.

Epidermal growth factor receptor (EGFR) expression is associated with a worse prognosis in gastric cancer patients undergoing curative surgery

BACKGROUND

In gastric cancer, the recurrence rate is high even after curative surgery. A relevant issue is the identification of independent prognostic factors to select high-risk patients; such features can be used as predictive factors for tailored therapies. In this study we have investigated the role of epidermal growth factor receptor (EGFR) expression as a prognostic marker for predicting cancer behavior and clinical outcome in gastric cancer patients undergoing potentially curative surgery.

METHODS

Epidermal growth factor receptor determination using a commercially available immunohistochemistry (IHC) kit was performed in tissues from 82 gastric cancer patients receiving primary surgical treatment and in 25 normal gastric mucosa specimens from noncancer patients. The EGFR positivity was correlated with disease recurrence and survival in univariate and multivariate analyses.

RESULTS

Forty-four percent (36 cases) of gastric cancers were EGFR positive. In 66 curatively treated patients, EGFR expression correlated with disease recurrence and poorer survival in both univariate and multivariate analyses. In a multivariate model for predicting recurrence and survival, advanced tumor extension (T(3) or T(4)), nodal metastases, and EGFR expression were the only independent covariates. In particular, EGFR expression was shown to be a significant predictor of poor prognosis among gastric cancer patients having the same stage according to the current TNM staging system.

CONCLUSIONS

These findings suggest that EGFR expression may be useful in identifying high-risk gastric cancer patients undergoing potentially curative surgery. Multimodal treatments should be considered in the adjuvant treatment of these patients.

Health-related quality of life among disease-free stomach cancer survivors in Korea

Previous studies about the quality of life (QOL) in stomach cancer survivors focused on selected clinical parameters and did not consider the broader implications for overall health and QOL. We evaluated the impact of demographic and treatment-related factors on the QOL of stomach cancer survivors. We asked 391 stage I-III stomach cancer survivors who had been disease-free for at least 1 year after surgery to complete a demographic questionnaire, the European Organization for Research and Treatment of Cancer QLQ-C30 questionnaire, and its stomach module, QLQ-STO22.Survivors undergoing total gastrectomy reported greater eating restrictions than those undergoing subtotal gastrectomy. Receiving chemotherapy or radiotherapy did not significantly affect any QLQ-C30 or QLQ-STO22 scores. Role and emotional functioning improved with increasing age, and stomach-specific symptoms (pain, eating restrictions, and anxiety) lessened. Compared with female survivors, male survivors had better physical and role functioning. Smoking status was also a significant negative predictor of physical functioning and anxiety. Comorbidities and selected demographic characteristics had a greater effect than type of treatment on the QOL of post-operative stomach cancer patients.