Surgical treatment results of intestinal and diffuse type gastric cancer. Implications for a differentiated therapeutic approach?

AIM

To study the outcome of patients who were surgically treated for primary gastric cancer with specific attention to differences in treatment results for intestinal and diffuse type tumours.

METHODS

All patients who underwent a potentially curative gastric resection between 1995 and 2011 in our institute were included. Patient, tumour and treatment characteristics were obtained retrospectively. Binary logistic and Cox regression models were used for multivariate analysis.

RESULTS

A consecutive series of 132 patients was included. Median follow-up was 53 months. There were no significant differences between patients with intestinal (N = 62) versus diffuse type (N = 70) gastric cancer with regard to the proportion of patients who underwent (neo)adjuvant treatment. Postoperative mortality was 2%. Pathological T- and N-stage were significantly more advanced for patients with diffuse type tumours. There was a significant difference in the percentage of microscopically irradical resections (2% versus 24%, p < 0.001) and median overall survival (129 versus 17 months, p < 0.001) between patients with intestinal type tumours and those with diffuse type tumours. On multivariate analysis, diffuse type histology was the only factor significantly associated with an R1 resection. In a multivariate Cox regression model, diffuse type histology was a significant adverse prognostic factor for overall survival.

CONCLUSIONS

Striking differences were found between patients with diffuse type tumours and those with intestinal type tumours. These differences call for a differentiated approach in the potentially curative treatment of these two tumour types.

Differences in outcomes of oesophageal and gastric cancer surgery across Europe

BACKGROUND

In several European countries, centralization of oesophagogastric cancer surgery has been realized and clinical audits initiated. The present study was designed to evaluate differences in resection rates, outcomes and annual hospital volumes between these countries, and to analyse the relationship between hospital volume and outcomes.

METHODS

National data were obtained from cancer registries or clinical audits in the Netherlands, Sweden, Denmark and England. Differences in outcomes were analysed between countries and between hospital volume categories, adjusting for available case-mix factors.

RESULTS

Between 2004 and 2009, 10 854 oesophagectomies and 9010 gastrectomies were registered. Resection rates in England were 18·2 and 21·6 per cent for oesophageal and gastric cancer respectively, compared with 28·5-29·9 and 41·4-41·9 per cent in the Netherlands and Denmark (P < 0·001). The adjusted 30-day mortality rate after oesophagectomy was lowest in Sweden (1·9 per cent). After gastrectomy, the adjusted 30-day mortality rate was significantly higher in the Netherlands (6·9 per cent) than in Sweden (3·5 per cent; P = 0·017) and Denmark (4·3 per cent; P = 0·029). Increasing hospital volume was associated with a lower 30-day mortality rate after oesophagectomy (odds ratio 0·55 (95 per cent confidence interval 0·42 to 0·72) for at least 41 versus 1-10 procedures per year) and gastrectomy (odds ratio 0·64 (0·41 to 0·99) for at least 21 versus 1-10 procedures per year).

CONCLUSION

Hospitals performing larger numbers of oesophagogastric cancer resections had a lower 30-day mortality rate. Differences in outcomes between several European countries could not be explained by differences in hospital volumes. To understand these differences in outcomes and resection rates, with reliable case-mix adjustments, a uniform European upper gastrointestinal cancer audit with recording of standardized data is warranted.

Anticancer therapy and apoptosis imaging

Early response prediction is considered an essential tool to obtain a more customized anticancer treatment because it allows for the identification of patients who will benefit most from a particular therapy and prevents the exposure of those patients to toxic, non-effective regimens. Recent discoveries of novel markers in functional imaging have created exciting opportunities for in vivo visualization and quantification of cell death. This review will focus on in vivo apoptosis imaging with various radiotracers as predictive tools for tumor response after anticancer therapy. Particular focus will be on annexin V imaging, a technique with the largest clinical experience to date. This article is part of a Special Issue entitled "Apoptosis: Four Decades Later".

Bcl-2 is a better ABT-737 target than Bcl-xL or Bcl-w and only Noxa overcomes resistance mediated by Mcl-1, Bfl-1, or Bcl-B

The novel anticancer drug ABT-737 is a Bcl-2 Homology 3 (BH3)-mimetic that induces apoptosis by inhibiting pro-survival Bcl-2 proteins. ABT-737 binds with equal affinity to Bcl-2, Bcl-xL and Bcl-w in vitro and is expected to overrule apoptosis resistance mediated by these Bcl-2 proteins in equal measure. We have profiled ABT-737 specificity for all six pro-survival Bcl-2 proteins, in p53 wild-type or p53-mutant human T-leukemic cells. Bcl-B was untargeted, like Bfl-1 and Mcl-1, in accord with their low affinity for ABT-737 in vitro. However, Bcl-2 proved a better ABT-737 target than Bcl-xL and Bcl-w. This was reflected in differential apoptosis-sensitivity to ABT-737 alone, or combined with etoposide. ABT-737 was not equally effective in displacing BH3-only proteins or Bax from Bcl-2, as compared with Bcl-xL or Bcl-w, offering an explanation for the differential ABT-737 sensitivity of tumor cells overexpressing these proteins. Inducible expression demonstrated that BH3-only proteins Noxa, but not Bim, Puma or truncated Bid could overrule ABT-737 resistance conferred by Bcl-B, Bfl-1 or Mcl-1. These data identify Bcl-B, Bfl-1 and Mcl-1, but also Bcl-xL and Bcl-w as potential mediators of ABT-737 resistance and indicate that target proteins can be differentially sensitive to BH3-mimetics, depending on the pro-apoptotic Bcl-2 proteins they are complexed with.

Influence of hospital type on outcomes after oesophageal and gastric cancer surgery

BACKGROUND

Outcomes after oesophagectomy and gastrectomy vary considerably between hospitals. Possible explanations include differences in case mix, hospital volume and hospital type. The present study examined the distribution of oesophagectomies and gastrectomies between hospital types in the Netherlands, and the relationship between hospital type and outcome.

METHODS

Data were obtained from the nationwide Netherlands Cancer Registry. Hospitals were categorized as university hospitals (UH), non-university teaching hospitals (NUTH) and non-university non-teaching hospitals (NUNTH). Hospital type-outcome relationships were analysed by Cox regression, adjusting for case mix, hospital volume, year of diagnosis and use of multimodal therapies.

RESULTS

Between 1989 and 2009, 10 025 oesophagectomies and 14 221 gastrectomies for cancer were performed in the Netherlands. The percentage of oesophagectomies and gastrectomies performed in UH increased from 17·6 and 6·4 per cent respectively in 1989 to 44·1 and 12·9 per cent in 2009. After oesophagectomy, the 3-month mortality rate was 2·5 per cent in UH, 4·4 per cent in NUTH and 4·1 per cent in NUNTH (P = 0·006 for UH versus NUTH). After gastrectomy, the 3-month mortality rate was 4·9 per cent in UH, 8·9 per cent in NUTH and 8·7 per cent in NUNTH (P < 0·001 for UH versus NUTH). Three-year survival was also higher in UH than in NUTH and NUNTH.

CONCLUSION

Oesophagogastric resections performed in UH were associated with better outcomes but, owing to variation in outcomes within hospital types, centres of excellence cannot be designated solely on hospital type. Detailed information on case mix and outcomes is needed to identify centres of excellence.

Preoperative chemotherapy does not influence the number of evaluable lymph nodes in resected gastric cancer

BACKGROUND

While it is suggested that more than 15 lymph nodes (LNs) should be evaluated for accurate staging of gastric cancer, LN yield in western countries is generally low. The effect of preoperative chemotherapy on LN yield in gastric cancer is unknown. The aim of the present study is to determine whether preoperative chemotherapy is associated with any difference in the number of LNs obtained from specimens of patients who underwent curative surgery for gastric adenocarcinoma.

PATIENTS AND METHODS

In 1205 patients from Memorial Sloan-Kettering Cancer Center (MSKCC) and 1220 patients from the Netherlands Cancer Registry (NCR) who underwent a gastrectomy with curative intent for gastric adenocarcinoma without receiving preoperative radiotherapy, LN yield was analyzed, comparing patients who received preoperative chemotherapy and patients who received no preoperative therapy.

RESULTS

Of the 2425 patients who underwent a gastrectomy, 14% received preoperative chemotherapy. Median LN yields were 23 at MSKCC and 10 in the NCR. Despite this twofold difference in LN yield between the two populations, with multivariate Poisson regression, chemotherapy was not associated with LN yield of either population. Variables associated with increased LN yield were institution, female sex, lower age, total (versus distal) gastrectomy and increasing T-stage.

CONCLUSIONS

In this patient series, treatment at MSKCC, female sex, lower age, total gastrectomy and increasing primary tumor stage were associated with a higher number of evaluated LNs. Preoperative chemotherapy was not associated with a decrease in LN yield. Evaluating more than 15 LNs after gastrectomy is feasible, with or without preoperative chemotherapy.

The effect of preoperative chemotherapy on lymph node yield in gastric cancer

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Background: While a minimum of 15 lymphnodes (LNs) should be evaluated for accurate staging of gastric cancer, LN yield in western countries is generally low. With the increasing use of preoperative chemotherapy, it is unknown what the effect of this treatment is on lymph node yield. The aim of the study is therefore to determine whether preoperative chemotherapy influences the number of LNs that can be obtained from specimens of patients who underwent curative surgery for gastric adenocarcinoma.

Methods: In1,205 patients from a high-volume U.S. center and 1,220 patients from the Netherlands Cancer Registry (NCR) who underwent a total or distal gastrectomy with curative intent for gastric adenocarcinoma, the LN yield was compared between patients who received preoperative chemotherapy and patients who received no neoadjuvant therapy. Multivariate Poisson regression was used to identify significant predictors of LN retrieval.

Results: Of the 2,425 patients who underwent a gastrectomy, 340 patients (14%) received preoperative chemotherapy. Median LN yields were 23 in the U.S. institution and 10 in the NCR. Separate multivariate analyses of the U.S. institution data and the NCR population showed in both groups that preoperative chemotherapy was not associated with a significant difference in LN yield (Table). Factors that were associated with higher LN yield were the same in both groups: female sex, younger age (6% more nodes with every 10 years decrease in age), total gastrectomy (vs. distal gastrectomy) and increasing tumor (T) stage.

Conclusions: In both a high-volume cancer center, and a population-based cancer registry, female sex, younger age, total gastrectomy and advanced tumor stage were associated with an increase in lymph node retrieval in surgical specimens. Preoperative chemotherapy did not influence lymph node yield after a resection for gastric cancer. The threshold for what should constitute an adequate assessment of regional lymph nodes after curative surgery for gastric cancer should not be changed after administration of preoperative chemotherapy.

[Table: see text]

No significant financial relationships to disclose.

Conditional survival nomogram after an R0 resection for gastric cancer

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Background: The risk of dying of cancer is highest in the first two years after a curative resection for gastric cancer. Therefore, the prognosis of patients who did not recur in the first two years is improved because they survived this critical period, a phenomenon called conditional survival. The US-derived gastric cancer nomogram predicts disease-specific survival (DSS) based on pathological variables. However, a disease-free interval after surgery, which improves the prognosis, is not captured by the nomogram. Therefore, it has only been used directly after surgery and not in the follow-up setting. The purposes of this study were to develop a conditional survival nomogram for 1, 2 and 3-year survivors (step 1) and to test if the introduction of follow-up variables would improve predictive accuracy of the nomogram in the follow-up setting (step 2).

Methods: In a combined US-Dutch population of 1642 patients who underwent an R0 resection for gastric cancer and for whom the old nomogram variables were available, a conditional survival nomogram based on the original variables was developed for one (N=1147), two (N=879) and three (N=721) year survivors (step 1). To improve predictive accuracy in the follow-up setting, weight loss, performance status (PS), hemoglobin (HGB), and albumin (ALB) at one year after resection were retrospectively collected and added to the baseline variables in a new nomogram (step 2).

Results: The conditional survival nomograms for 1, 2 and 3-year survivors (step 1) showed a high predictive accuracy in the calibration plots. Surviving one, two and three years shows a median improvement of 5-year DSS of 4%, 9% and 14% respectively. The introduction of weight loss, PS, HGB, and ALB at one year after surgery (step 2) did not improve this nomogram, but availability of these variables was limited.

Conclusions: A strongly predictive conditional survival nomogram was developed, giving an improved prognosis for 1, 2 and 3-year survivors of gastric cancer. Introduction of variables available at one year after resection did not further improve this nomogram. This might be caused by the limited availability of follow-up data, as well as the strong predictive accuracy of the original variables.

No significant financial relationships to disclose.

Toxicity and complications of preoperative chemoradiotherapy for locally advanced rectal cancer

BACKGROUND

Capecitabine is an attractive radiosensitizer. In this study acute toxicity and surgical complications were evaluated in patients with locally advanced rectal cancer following total mesorectal excision (TME) after preoperative chemoradiotherapy (CRT) with capecitabine.

METHODS

Between 2004 and 2008, consecutive patients with clinical tumour category (cT) 3-4 (with a threatened circumferential resection margin or cT3 within 5 cm of the anal verge) or clinical node category 2 rectal cancer were treated with preoperative CRT (25 × 2 Gy, capecitabine 825 mg/m(2) twice daily, days 1-33). TME followed 6 weeks later. Toxicity was scored according to the Common Terminology Criteria (version 3.0) and Radiation Therapy Oncology Group scoring systems. Treatment-related surgical complications were evaluated for up to 30 days after discharge from hospital using the modified Clavien-Dindo classification.

RESULTS

Some 147 patients were analysed. The mean cumulative dose of capecitabine was 95 per cent and 98·0 per cent of patients received at least 45 Gy. One patient died from sepsis following haematological toxicity. Grade 3-5 toxicity developed in 32 patients (21·8 per cent), especially diarrhoea (10·2 per cent) and radiation dermatitis (11·6 per cent). There were no deaths within 30 days after surgery. Anastomotic leakage and perineal wound complications developed after 13 of 47 low anterior resections and 23 of 62 abdominoperineal resections. Surgical reintervention was required in 30 patients. Twenty-seven patients (19·6 per cent) of 138 patients who had a laparotomy were readmitted within 30 days after initial hospital discharge.

CONCLUSION

Preoperative CRT with capecitabine is associated with acceptable acute toxicity, significant surgical morbidity but minimal postoperative mortality.