Evaluation of Clinical Efficacy of New Medical Treatments in Advanced Colorectal Cancer. Results of a Workshop Organized by the Eortc Gitccg

During the last few years several factors have contributed to an increasing change in the medical treatment of advanced colorectal cancer. Among them are the more general acceptance of the impact of chemotherapy on quality of life and survival in first as well as in second-line treatment, the introduction of new drugs and the definition of novel endpoints which can roughly be defined as “patient benefit”. For this reason the European Organization for Research and Treatment of Cancer (EORTC) Gastrointestinal Tract Cancer Cooperative Group (GITCCG) felt it was appropriate to organize a workshop with experts from different countries and national groups to discuss in depth several aspects concerning the treatment of patients with advanced colorectal cancer.

Pulmonary Lymphangioleiomyomatosis: A Case Report in Postmenopausal Woman Treated with Pleurodesis and Progesterone (Medroxyprogesterone Acetate)

The main problem in the treatment of pulmonary lymphangioleiomyomatosis, which frequently occurs in the reproductive age, is the control of chylothorax and disease progression. We herein report a case of a 62-year-old woman who underwent surgery for recurrent chylothorax. Histologic examination of lung and lymph node biopsies demonstrated lymphangioleiomyomatosis. Thirty-six months after tetracycline pleurodesis and high-dose medroxyprogesterone acetate therapy, the disease was stable and chylothorax effectively controlled. It would therefore appear that hormonal treatment with medroxyprogesterone acetate may be beneficial in postmenopausal women.

Genetic Heterogeneity of Variable Number Tandem Repeats in Thymidylate Synthase Gene in Colorectal Cancer Patients

Purpose

To analyze the genetic variability in a variable number of tandem repeats (VNTR) in the thymidylate synthase (TS) enhancer promoter region and assess the influence of functional alterations in mismatch repair genes by analyzing constitutional and tumoral DNA from patients with colorectal adenocarcinoma with a high microsatellite instability (MSI-H) or microsatellite stability (MSS) status.

Patients and methods

Patients who underwent surgery for colorectal adenocarcinoma were selected from the colorectal database of our institute and, on the basis of MSI status, assigned to a study group and a control group: group A, MSI-H; group B, MSS. Microsatellite status was investigated using the Bethesda recommended panel (BAT-26, BAT-25, D2S123, D5S346, D17S250). In MSI-H patients an additional analysis was made of the microsatellite loci D18S61 and D18S58, both mapping in the region containing the TS gene (18p11.2–11.32). Based on the number of altered microsatellites (≥2, 1, or 0), tumors were considered as having high (MSI-H) or low (MSI-L) instability or microsatellite stability (MSS), respectively. Genotyping for thymidylate synthase promoter polymorphism was carried out on constitutional and tumor DNA of each patient by PCR amplification of the polymorphic region.

Results

MSI-H was found in 55 patients (group A) and MSS in 50 patients (group B). In none of the MSI-H patients was microsatellite instability found in the additional D18S61 and D18S58 loci. In five group A and ten group B cases the analysis was not performed because constitutional DNA and/or tumoral DNA were not amplifiable. Homozygotes for the triple repeat variant (3R/3R) displayed only the large PCR product, homozygotes for the double repeat variant (2R/2R) displayed only the smaller PCR product, while heterozygotes (2R/3R) displayed both the larger and smaller PCR products. In 3/50 (6%) group A patients and 5/40 (12%) group B patients repeat variations were found in tumoral DNA.

Conclusion

Our findings demonstrate that there is genetic homogeneity between constitutional and tumoral DNA but do not support the hypothesis that mismatch repair genes are involved in VNTR recombinant events in TS gene variability.

Hyperthermic Isolated Perfusion with Low-Dose TNFα and Doxorubicin in Patients with Locally Advanced Soft Tissue Limb Sarcomas

We report here the results of 27 patients who underwent hyperthermic isolated limb perfusion with low-dose TNFalpha (1 mg) and doxorubicin (8.5 mg/l of limb volume) for locally advanced soft tissue sarcomas. A tumor response was observed in 85% of cases. After a median follow-up of 30 months, limb salvage and local disease control were achieved in 82 and 85% of patients, respectively. Locoregional toxicity was low or mild in 14 patients, while 2 patients had severe limb toxicity. Systemic side effects were negligible. The perfusate/plasma area under the curve (AUC) ratio for TNFalpha was 56. HILP with low-dose TNFalpha and DXR proved to be an active neoadjuvant drug regimen against limb-threatening STS.

Systematic review of surgical treatment of subclinical Cushing's syndrome

BACKGROUND

Subclinical Cushing's syndrome (SCS) is a condition of biochemical cortisol excess without the classical clinical features of overt hypercortisolism; it may be associated with some consequences of metabolic syndrome. The most appropriate treatment remains controversial. This study aimed to assess the outcomes of adrenalectomy for SCS.

METHODS

A systematic review was performed. MEDLINE, Embase and Cochrane Databases (1980-2013) were searched for studies reporting the outcomes of unilateral adrenalectomy with respect to hypertension, diabetes, dyslipidaemia, obesity and osteoporosis in patients with SCS. Studies with a questionable diagnosis of SCS, bilateral adrenal involvement and insufficient data were excluded.

RESULTS

Of the 105 papers screened, seven were selected; there were six retrospective studies and one randomized clinical trial, including 230 patients. Data analysis was limited by heterogeneity in definition of SCS and endpoints. Hypercortisolism was cured in all operated patients. Laparoscopy was the preferred approach, with a morbidity rate of 0·8 per cent. A beneficial effect of surgery on blood pressure, glucometabolic control and obesity was evident in all studies, with cure or improvement in 72, 46 and 39 per cent of patients respectively, compared with conservative management. The results for lipid metabolism were equivocal, because of a decrease in triglyceridaemia but discordant effects on cholesterol metabolism among the different studies. No beneficial effects on osteoporosis were found.

CONCLUSION

Laparoscopic adrenalectomy seems to be beneficial in reversing several metabolic effects of hypercortisolism, with a low morbidity rate. However, the heterogeneity and low quality of the available studies preclude definitive recommendations.

Randomized trial on adjuvant treatment with FOLFIRI followed by docetaxel and cisplatin versus 5-fluorouracil and folinic acid for radically resected gastric cancer

BACKGROUND

Some trial have demonstrated a benefit of adjuvant fluoropirimidine with or without platinum compounds compared with surgery alone. ITACA-S study was designed to evaluate whether a sequential treatment of FOLFIRI [irinotecan plus 5-fluorouracil/folinic acid (5-FU/LV)] followed by docetaxel plus cisplatin improves disease-free survival in comparison with 5-FU/LV in patients with radically resected gastric cancer.

PATIENTS AND METHODS

Patients with resectable adenocarcinoma of the stomach or gastroesophageal junction were randomly assigned to either FOLFIRI (irinotecan 180 mg/m(2) day 1, LV 100 mg/m(2) as 2 h infusion and 5-FU 400 mg/m(2) as bolus, days 1 and 2 followed by 600 mg/m(2)/day as 22 h continuous infusion, q14 for four cycles) followed by docetaxel 75 mg/m(2) day 1, cisplatin 75 mg/m(2) day 1, q21 for three cycles (sequential arm) or De Gramont regimen (5-FU/LV arm).

RESULTS

From February 2005 to August 2009, 1106 patients were enrolled, and 1100 included in the analysis: 562 in the sequential arm and 538 in the 5-FU/LV arm. With a median follow-up of 57.4 months, 581 patients recurred or died (297 sequential arm and 284 5-FU/LV arm), and 483 died (243 and 240, respectively). No statistically significant difference was detected for both disease-free [hazard ratio (HR) 1.00; 95% confidence interval (CI): 0.85-1.17; P = 0.974] and overall survival (OS) (HR 0.98; 95% CI: 0.82-1.18; P = 0.865). Five-year disease-free and OS rates were 44.6% and 44.6%, 51.0% and 50.6% in the sequential and 5-FU/LV arm, respectively.

CONCLUSIONS

A more intensive regimen failed to show any benefit in disease-free and OS versus monotherapy.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01640782.

Gastrointestinal carcinoid: epidemiological and survival evidence from a large population-based study (n = 25 531)

BACKGROUND

Owing to its rarity, the published evidence on gastrointestinal (GI) carcinoid is often based on small series of patients or population-based studies regarding all neuroendocrine tumors. Here, we present a comprehensive epidemiological and survival analysis of the largest cohort of patients with GI carcinoid ever reported.

PATIENTS AND METHODS

Patients with histological diagnosis of GI carcinoid (n = 25 531) were identified from the Surveillance Epidemiology End Results (SEER) database (including 18 USA cancer registries and spanning the 1973-2009 time frame). Demographic and disease data were used for epidemiological and survival analyses.

RESULTS

The incidence of GI carcinoid is steadily increasing over the past three decades at a rate higher than any other cancer [annual percentage change (APC) = 4.4, 95% confidence interval (CI) 4.0-4.8]. These patients have a higher risk of further primary tumor (standardized incidence ratio, SIR = 1.15, 95% CI 1.10-1.21), but also a reduced risk of skin melanoma (SIR = 0.64, 95% CI 0.41-0.95). Despite the overall favorable prognosis (5-year disease-specific and relative survival rate: 91.3% and 87.4%, respectively), the mortality rate is increasing over time (APC = 3.5, 95% CI 3.0-4.0) and the 5-year survival rate of patients dying of GI carcinoid (28.5%), though better than that reported for GI cancers in general (8.4%), cannot be considered satisfactory. Finally, a nomogram is provided to predict patient survival on the basis of clinico-pathological factors independently associated with prognosis at multivariate analysis.

CONCLUSIONS

These findings can be clinically useful for the management of patients with GI carcinoid and eagerly prompt the continuous effort to develop more effective therapeutic strategies against this slow-growing but chemoresistant tumor.

Circulating cell-free DNA: a promising marker of regional lymphonode metastasis in breast cancer patients

PURPOSE

We undertook the current study with untreated breast cancer to (1) role the variations in the plasma levels of cfDNA and the size distribution in early stage, (2) determine the frequency in plasma of methylation of three candidate genes, RASSF1A, MAL, and SFRP1, and (3) to determine whether detection of cfDNA variations and methylation changes in plasma might have specific clinical utility.

METHODS AND MATERIALS

Thirty-nine patients woman patients (median age 64 years; range, 36-90 years) who underwent surgery for primary BR and 49 healthy females' subjects (control group without any breast lesion) were evaluated. The cfDNA levels were analyzed using quantitative real-time polymerase chain reaction of β-globin. Based on the ALU repeats, the cfDNA was considered as either total (fragments of 115 bp, ALU115) or tumoral (fragments of 247 bp, ALU247). The association between the levels of the ALU247, ALU115 repeat, and ALU 247/115and the pathologic tumor characteristics was analyzed. Used methylight qPCR method, cfDNA from plasma samples of healthy donors and patients with breast cancer were evaluated for the diagnotic value of the methylation status of three genes (RASSF1A, MAL, SFRP1) frequently methylated in breast cancer.

RESULTS

The baseline levels of cfDNA were significantly higher in the patients with cancer, and the level of ALU247 was the most accurate circulating cfDNA marker in discriminating the cancer from non-cancer subjects. A high statistical significance was found by considering the T stage and patients with regional LN metastasis positive cancers showed significantly higher cfDNA level of ALU247. Moreover, patients with methylation of at least one of the gene under investigate showed a higher quantity of cfDNA ALU115 (p< 0.0001) and ALU247 level (p< 0.0001).

CONCLUSIONS

We observed that necrosis could be a potential source of circulating tumour-specific cfDNA ALU247; and that cfDNA ALU247 and methylated cfDNA (RASSF1A, MAL and SFRP1) are both a phenotypic feature of tumour biology.

Adherence to treatment guidelines for primary sarcomas affects patient survival: a side study of the European CONnective TIssue CAncer NETwork (CONTICANET)

BACKGROUND

The impact of adherence to clinical practice guidelines (CPGs) for loco-regional treatment (i.e. surgery and radiotherapy) and chemotherapy on local disease control and survival in sarcoma patients was investigated in a European study conducted in an Italian region (Veneto).

PATIENTS AND METHODS

The completeness of the adherence to the Italian CPGs for sarcomas treatment was assessed by comparing the patient's charts and the CPGs. Propensity score-adjusted multivariate survival analysis was used to assess the impact of CPGs adherence on patient clinical outcomes.

RESULTS

A total of 151 patients were included. Adherence to CPGs for loco-regional therapy and chemotherapy was observed in 106 out of 147 (70.2%) and 129 out of 139 (85.4%) patients, respectively. Non-adherence to CPGs for loco-regional treatment was independently associated with AJCC stage III disease [odds ratio (OR) 1.77, P = 0.011] and tumor-positive excision margin (OR 3.55, P = 0.003). Patients not treated according to the CPGs were at a higher risk of local recurrence [hazard ratio (HR) 5.4, P < 0.001] and had a shorter sarcoma-specific survival (HR 4.05, P < 0.001), independently of tumor stage.

CONCLUSIONS

Incomplete adherence to CPGs for loco-regional treatment of sarcomas was associated with worse prognosis in patients with non-metastatic tumors.

Telomerase is an independent prognostic marker of overall survival in patients with colorectal cancer

Background:

Colorectal cancer (CRC) is an important cause of cancer-related death. Prediction of recurrence is an important issue in the treatment of disease, particularly for stage II patients. The level of telomere-specific reverse transcriptase (hTERT), the catalytic component of the telomerase complex, increases along with CRC progression, but its prognostic value is still unclear.

Methods:

One hundred and thirty-seven CRC patients were studied for hTERT expression in tumour cells by real-time PCR. hTERT level was evaluated as a prognostic factor of overall survival (OS) in all patients and of disease recurrence in a subgroup of 50 stage II patients.

Results:

The median hTERT level was 93.8 copies (interquartile range 48–254). Patients with high hTERT levels (above the median) showed a significantly worse survival than those with low hTERT levels (below the median; log-rank test P<0.0001; hazard ratio (HR)=3.30 (95% confidence interval (CI) 1.98–5.52); P<0.0001). The negative prognostic value of high hTERT level is independent of the pathological stage and microsatellite instability (HR=2.09 (95% CI 1.20–3.64), P=0.009). Moreover, in stage II CRC, high hTERT levels identified patients with a higher risk of disease recurrence (HR=3.06 (95% CI 1.03–9.04), P=0.043) and death (HR=3.24 (95% CI 1.37–7.71), P=0.008).

Conclusion:

hTERT level is an independent prognostic marker of OS in CRC patients. In addition, assessment of hTERT level could improve stratification of stage II CRC patients for the risk of disease recurrence.

Multivariate analysis approach to the serum peptide profile of morbidly obese patients

BACKGROUND

Obesity is currently epidemic in many countries worldwide and is strongly related to diabetes and cardiovascular disease. Mass spectrometry, in particular matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) is currently used for detecting different pattern of expressed protein. This study investigated the differences in low molecular weight (LMW) peptide profiles between obese and normal-weight subjects in combination with multivariate statistical analysis.

MATERIALS

Serum samples of 60 obese patients and 10 healthy subjects were treated by cut-off membrane (30000 Da) to remove the most abundant proteins. The filtrates containing the LMW protein/peptides were analyzed by MALDI-TOF mass spectrometry. Dataset was elaborated to align and normalize the spectra. We performed cluster analysis and principal component analysis to detect some ionic species that could characterize and classify the subject groups.

RESULTS

We observed a down-expression of ionic species at m/z 655.94 and an over-expression of species at m/z 1518.78, 1536.77, 1537.78 and 1537.81 in obese patients. Furthermore we found some ionic species that can distinguish obese patients with diabetes from those with normal glucose level.

CONCLUSION

Serum peptide profile of LMW associate with multivariate statistical approach was revealed as a promising tool to discriminate and characterize obese patients and it was able to stratify them in relation to comorbidity that usually are associated with this disease. Further research involving a larger sample will be required to validate these findings.

Histopathological characteristics of subsequent melanomas in patients with multiple primary melanomas

BACKGROUND

Multiple primary melanomas (MPM) occur in up to 20% of melanoma patients, and subsequent tumours seem to have a favourable histopathological pattern.

OBJECTIVE

A prospectively collected cohort of 194 patients with MPM was retrospectively reviewed to investigate clinical and histopathological features of first and subsequent melanomas.

METHODS

Patients with MPM who were diagnosed at our Department (1985-2011) and who attended at least a follow-up control yearly were identified.

RESULTS

The number of nevi was <10, 10-50 and >50 in 8.7%, 41% and 50.3% of patients respectively. Histopathological dysplastic nevi have been diagnosed in 105 patients. During a median follow-up of 58 months, 159 (81.9%), 24 (12.3%), 7 (3.6%) and 4 (2%) patients developed 2, 3, 4 and ≥ 5 melanomas, respectively. The median time to second primary melanoma was 45 months. The second primary melanoma was diagnosed within 1-year and after 5-year from the first melanoma in 36.6% and 17.3% of patients respectively. First and second primary melanomas were in situ in 41 (21%) and 104 (54%) patients respectively (P < 0.001). Among patients with ≥ 2 invasive melanomas (N = 80), median tumour thickness and ulceration of first and second primaries were 0.91 and 0.44 mm (P <0.001), and 32% and 7.7% (P = 0.001) respectively.

CONCLUSIONS

Subsequent melanomas occurred within 1-year from the appearance of the first melanoma in 36% of patients with MPM, while a late melanoma diagnosis was detected in 17% of cases. Second primary melanoma had favourable histopathological features. Our findings support long-term skin surveillance to detect subsequent melanomas at an early stage.

Validation of the new AJCC TNM staging system for gastric cancer in a large cohort of patients (n = 2,155): focus on the T category

BACKGROUND

The prognostic value of T subclassification in patients with gastric carcinoma has been just implemented in the new AJCC TNM staging system, which has reclassified T2a and T2b into T2 and T3 tumors, respectively. The aim of the present study was to validate the prognostic significance of the new T categorization within the frame of the latest TNM staging system.

METHODS

We retrospectively reviewed the records of 686 T2/T3 patients among 2155 subjects who underwent radical resection for gastric carcinoma at six Italian centers from 1988 through 2006.

RESULTS

Upon multivariate analysis, the new T categories, extent of lymph node dissection (D) and patient's age were retained by the survival model as independent prognostic factors. In particular, the death risk for patients with T3 tumors was higher than that of patients with T2 tumors (HR: 1.42, P = 0.005). Among the 686 patients previously classified as having T2 tumors, patients with T2 and T3 disease were 270 (39.4%) and 416 (60.6%), respectively. After a median follow-up of 55 months, the 5-year overall survival rates were 67.3% and 52.3% for patients with T2 and T3 tumors, respectively (P < 0.001). The survival advantage for the T2 as compared to T3 category was maintained even when N0 and N+ patients were separately considered (P = 0.0154 and P < 0.001, respectively).

CONCLUSIONS

Our data confirm the prognostic difference between the newly proposed T2 and T3 categories, which should be implemented in the routine clinical practice to improve risk stratification of patients with gastric cancer.

p53 gene alterations and protein accumulation in colorectal cancer

Aim-To correlate immunohistochemical staining with single strand conformation polymorphism (SSCP) analysis of the p53 gene in colorectal cancer in order to understand how the findings provided by the two techniques complement each other in defining p53 functional status.Methods-Frozen tumour tissue from 94 patients with colorectal cancer was studied for p53 protein accumulation and gene mutations. Accumulation of p53 protein was detected by immunohistochemistry using PAb1801 and BP53-12-1 monoclonal antibodies. The findings were then compared with SSCP analysis of exons 5 to 8 of the p53 gene. All cases with a positive result by SSCP analysis were confirmed by sequencing.Results-Nuclear staining was observed in 51 (54.2%) cases. SSCP analysis of the DNA amplified by PCR revealed that the electrophoretic pattern had shifted in 30 cases; sequence analysis confirmed the occurrence of a mutation in 29 cases and of a polymorphism in one. In 27 cases both assays gave a positive result, and in 40 both were negative; therefore, concordance between PCR-SSCP and immunohistochemistry was seen in 72% of cases.Conclusion-The data indicate that positive immunostaining corresponds with the presence of a mutation in most, but not all, cases studied; other mechanisms could be responsible for stabilisation and accumulation of p53 protein in the nucleus. Nonsense mutations which do not confer stability on the protein will not be detected by immunohistochemistry and false negative results can also occur with SSCP analysis.

Tumor response is predicted by patient genetic profile in rectal cancer patients treated with neo-adjuvant chemo-radiotherapy

The aim of the study was the identification of a pharmacogenetic profile predictive of the tumor regression grade (TRG), considered as tumor response parameter, after neo-adjuvant treatment in rectal cancer patients. A total of 238 rectal cancer patients treated in a neo-adjuvant setting by a fluoropyrimidines-based chemo-radiotherapy (RT) were genotyped for 25 genetic polymorphisms in 16 genes relevant for treatment-associated pathways. Two polymorphisms were associated with TRG in a multivariate analysis: hOGG1-1245C > G, which can affect radiosensitivity and MTHFR-677C > T, which is involved in fluoropyrimidines action. Patients bearing at least one variant allele had a lower chance to get TRG ≤ 2 (OR = 0.46 95% CI 0.23-0.90, P = 0.024; and OR = 0.48 95% CI 0.24-0.96, P = 0.034; respectively). An association trend was observed for ABCB1-3435C > T, which is responsible for the multi-drug resistance (odds ratio (OR) = 1.96, 95% confidence interval (CI) 0.98-3.95, P = 0.057). Exploratory classification and regression tree (CART) analysis highlighted high-order gene-gene and gene-environment interactions and a genetic signature associated with differential response, with hOGG1-1245C > G as the most predictive factor. Other significant variables were: ABCB1-3435C > T, MTHFR-677C > T, ERCC1-8092C > A, ABCC2-1249G > A, XRCC1-28152G > A, XRCC3-4541A > G and patients gender. On the basis of CART results, patients were categorized into three groups according to tumor response probability: intermediate and high profiles had a higher probability to get TRG ≤ 2 as compared with low profiles (OR = 4.12 95% CI 1.46-11.65, P < 0.001 and OR = 12.44, 95% CI 5.52-28.04, P < 0.0001, respectively). This study evidences a major role of hOGG1-1245C > G and MTHFR-677C > T polymorphisms in the tumor response of rectal cancer patients treated with chemo-RT in neo-adjuvant setting, and shows the relevance of gene-gene and gene-environment interactions for complex phenotypes as tumor response.

Peptide-based anticancer vaccines: recent advances and future perspectives

Anticancer active immunotherapy embodies the ideal antitumor therapy, as it theoretically combines target specificity with long-term disease control. Peptide-based cancer vaccines represent the most specific approach to polarize the immune system against malignant cells, since they are preparations made of single epitopes, the minimal immunogenic region of an antigen. Despite the strong rational, the promising preclinical results and the frequent induction of antigen-specific immune responses, peptide-based cancer vaccines have yielded relatively poor results in the clinical setting, a phenomenon likely due to the immunosuppressive properties of the tumor microenvironment that allow malignant cells to evade both naturally occurring and therapeutically induced immune surveillance. Nevertheless, advances in the engineering of peptides and in our understanding of the molecular mechanisms underlying an effective immune response against tumors have renewed the enthusiasm for peptide-based vaccination regimens in the setting of cancer, and a variety of clinical trials are being conducted based on the use of peptides. This review will describe the most recent insights in the rational design of peptide-based cancer vaccines, as well as the challenges to successful anticancer immunotherapy based on these short amino acid chains.

[Adjuvant chemotherapy after radical liver resection in the treatment of metastases from colorectal carcinoma]

Liver metastases are the leading cause of death in patients with colorectal carcinoma: approximately 25% present with metastases at diagnosis of the primary tumor and 30-50% will eventually develop metastases. Surgical therapy for metastases is the only curative treatment that will ensure five-year survival in 30-60% of patients; however, in 30-50% of these patients liver disease will recur. To improve these rates, various different studies have investigated the efficacy of postsurgical adjuvant therapy. The majority of randomized studies evaluated the efficacy of intra-arterial infusion associated or not with postsurgical systemic adjuvant treatment: this approach demonstrated benefit in terms of control of recurrent of liver disease but not in terms of overall survival. A reduction in the recurrence of liver disease was found in the two randomized studies published to date on the efficacy of systemic adjuvant therapy, and an improvement in survival in one trial. Given these data and the results obtained with the use of last generation chemotherapeutic agents (oxaliplatin and irinotecan) in the treatment of unresectable liver metastases from colorectal carcinoma, it can be conjectured that ongoing randomized clinical trials may confirm a significant advantage of adjuvant chemotherapy in the control of recurrence of liver disease and overall survival.

Use of a prognostic pathway signature for colorectal cancer comprised of EGFR/COX2 and imatinib drug target activation to predict occult metastasis in M0 CRC

4042

Background: Development of distant metastasis is the main cause of death among CRC patients. Approximately 30% of CRC patients initially staged M0-N0 die from tumor recurrence. Previously, we determined that members of EGFR/PDGFR/cAbl/cKit pathways were hyperactivated in hepatic synchronous CRC metastasis compared to primary tumor. In order to determine if this signature was a distinguished repertoire of the early stage primary tumor, we analyzed 58 CRC M0 at the moment of the diagnosis that upon 5 yr follow-up had differing disease progressions. Methods: All tissues were immediately snap frozen after surgery. Reverse phase protein microarray (RPMA) was performed using microdissected material to generate multiplexed pathway profiling. For each sample 75 different endpoints were analyzed. Results: Statistical comparison of the 75 endpoints in 8 M0 patients who progressed to M1 and 50 patients who remained M0 regardless of initial staging, revealed a number of signaling proteins whose activation/phosphorylation were elevated and subsumed in a linked pathway. Specifically COX2 and c-Kit/PDGFR/Notch were highly activated in the 8 patients with occult metastasis. A prognostic pathway signature comprised of 13 interlinked molecules was developed. Univariate, ROC and Kaplan-Meier analysis of this signature revealed a statistically significant prognostic signature with an AUC of 0.87 and a 95% confidence interval. Conclusions: A signaling portrait of 13 interlinked proteins provided a strong prognostic indicator for metastasis regardless of stage. This signature was comprised of the phosphorylation/activation of growth factor receptors, including the entire suite of Gleevec targets. A large number of these prognostic signature components were previously found activated in the metastatic lesions themselves which indicates a potential functional role of this linked protein network in metastatic progression and maintenance. If validated in larger study sets, clinical trials to test Gleevec therapy combined with Cox2 /EGFR inhibitors to prevent/delay development of distant metastasis in patients with M0 should be considered.

[Table: see text]

Cell-free circulating DNA as a promising marker of colorectal cancer detection and progression

11059

Background: Since the pathologic stage is the most powerful prognostic factor for colorectal cancer (CRC), there is a strong need of non-invasive methods for early detection. Cell-free circulating DNA (cfDNA) released from cancer cells varies in size. It has been suggested that cfDNA (ALU repeats of 115 bp, representative of total DNA; ALU repeats of 247 DNA, representative of tumor DNA) may be associated with presence of tumor. Aim of this study was then to investigate whether the cfDNA may have a role as marker of CRC detection and progression. Methods: cfDNA was extracted from plasma samples from 136 patients with primary CRC at different stages [median age 64 yrs; male/female 78/58; stages I-II, 61; stages III-IV, 75], and from 24 patients with adenomas [median age 67 yrs; male/female 17/7)] and from 55 clean-colon healthy subjects [median age 56 yrs; male/female 13/43). cfDNA was assessed by quantitative real-time PCR (qPCR) of ALU repeats with 2 sets of primers (115 and 247 bp) amplifying different lengths of DNA. The levels of cfDNA (ALU-115, ALU-247) of CRC patients (stages I-II and stages III-IV) were compared with those of healthy subjects and patients with adenoma. Results: The median concentrations of total cfDNA (ALU115) in the plasma samples from patients with stages III-IV and stages I-II CRC, adenoma and normal controls were 52,4, 11.9; 1.9, and 1.7 ng/ml, respectively (p<.0001). The corresponding figures for tumor-related cfDNA (ALU247) were 48.8, 4.7, 2.2, and 0.7 ng/ml, respectively. (p<.0001). With a cut-off of 4.86 ng/ml, total DNA (ALU115) showed a sensitivity of 78.52 (95% CI 70.6–85.1) and a specificity of 86.08 (95% CI 76.4–92.8) in distinguishing patients with CRC from non-CRC [AUC: 0.860 (95% CI 0.81–0,90), p-value=.0001]. With a cut-off of 3.04, cfDNA tumor-related (ALU247) showed a sensitivity of 77.94 (95% CI 70.0–84.6) and a specificity of 82.28 (95% CI 72.1–90.0) in distinguishing patients with CRC from non-CRC [AUC: 0.864 (95% CI 0.81–0,91), p-value=.0001]. Conclusions: Both ALU115 and ALU 247 fragments of circulating cfDNA seem promising non-invasive molecular markers of detection and progression of CRC. The findings of the current study require to be confirmed on larger cohorts of patients with CRC and colonic adenoma.

No significant financial relationships to disclose.

Resection line involvement after gastric cancer surgery: clinical outcome in nonsurgically retreated patients

PURPOSE

Resection line infiltration (RLI) after surgical treatment represents an unfavorable prognostic factor in advanced gastric cancer. We performed a retrospective analysis of 89 patients with resection line involvement who did not undergo reoperation.

METHODS

On behalf of the Italian Research Group for Gastric Cancer, we present the characteristics and outcome of 89 patients who were submitted to surgical resection for gastric cancer from 1988 to 2001 and did not undergo reoperation because of disease extension or associated pathologies.

RESULTS

RLI was significantly higher in patients with T4 tumors and diffuse histological type. Anastomotic leakages were observed in 4.8% of infiltrated esophageal resection margins, whereas 1.9% of infiltrated duodenal resection lines showed duodenal fistulas. Five-year overall survival of patients with RLI was 29%. Prognosis was not affected by RLI in early forms (100% 5-year survival); however, 5-year survival in T2 and T3 stages was significantly lower with respect to the same stages without residual tumor. The influence of RLI on prognosis was confirmed in N0 as well as in N1 and N2 patients. RLI also was an independent prognostic at multivariate analysis (odds ratio = 1.5; 95% confidence interval, 1.08-2.08; P = 0.0144).

CONCLUSIONS

RLI significantly affects long-term survival of advanced gastric cancer. The impact on prognosis is independent of lymph node involvement. Patients in good general condition for whom radical surgery is possible should be considered for reoperation.

Prognostic value of subclassification of T2 tumours in patients with gastric cancer

BACKGROUND

This study was designed to evaluate the prognostic value of tumour stage T2 subcategorization (T2a and T2b) in patients with gastric carcinoma.

METHODS

Clinicopathological details of a prospective series of patients who had radical resection of gastric adenocarcinoma in a single institution were analysed. Univariable and multivariable survival analyses were performed with the log rank test and Cox's model respectively.

RESULTS

Of 373 evaluable patients, 49 (13.1 per cent) had a T2a and 143 (38.3 per cent) a T2b tumour. At a median follow-up of 35.5 months, the 5-year overall survival rate was 73 and 31.1 per cent for patients with T2a and T2b lesions respectively (P < 0.001). On multivariable analysis, T stage remained an independent prognostic factor. Compared with T1a, the mortality risk for patients with T1b (hazard ratio (HR) 1.00; P = 0.992) and T2a (HR 0.97; P = 0.916) tumours was similar; by contrast, the risk of death associated with T2b (HR 1.81; P = 0.031) and T3 (HR 1.89; P = 0.038) lesions was significantly greater than for T1a tumours.

CONCLUSION

Subclassification of T2 tumours should be undertaken routinely in order to stratify patients with gastric cancer more accurately in terms of their mortality risk.

Metachronous hepatic metastases from gastric carcinoma: a multicentric survey

BACKGROUND

The treatment of hepatic metastases from gastric cancer is controversial, due to biologic aggressiveness of the disease.

OBJECTIVE

To survey the clinical approach to the subset of patients presenting with metachronous hepatic metastases as sole site of recurrence after curative resection of gastric cancer, focusing on the results achieved by different therapies and to investigate the prognostic factors of major clinical relevance.

METHODS

Retrospective multi-center chart review evaluating 73 patients, previously submitted to D >or= 2 gastrectomy for gastric cancer, who developed exclusive hepatic recurrence. Prognostic factors related to the patient, to the gastric malignancy and its treatment, and to the metastatic disease and its therapy were evaluated.

RESULTS

Forty-five patients received supportive care, 17 were submitted to chemotherapy, and 11 to hepatic resection. Survival was independently influenced by the variables T (p=0.019), N (p=0.05) and G (p=0.018) of the gastric primary and by the therapeutic approach to the metastases (p<0.005). In particular, T4 gastric cancer, presence of lymph-node metastases and G3 tumor displayed a negative prognostic value. Therapeutic approach to the metastases was the principal prognostic variable: 1, 2, and 3 years survival rates were 22.2%, 4.4% and 2.2%, respectively, for patients without specific treatment; 44.9%, 12.8% and 6.4% after chemotherapy (p=0.08) and 80.8%, 30.3% and 20.2% after surgical resection (p<0.001).

CONCLUSIONS

Our data suggest some clinical criteria that may facilitate selection of therapy for patients with hepatic recurrence after primary gastric cancer resection. The best survival rates are associated with surgical treatment, which should be chosen whenever possible.

Indexes of surgical quality in gastric cancer surgery: experience of an Italian network

BACKGROUND

Short-term results of gastric cancer surgery vary remarkably worldwide, and international surgical quality criteria are urgently needed. To contribute to defining these criteria, we reviewed short-term results of gastrectomy for gastric cancer in three centers of the Italian Research Group for Gastric Cancer, with an average of 24.7, 29.5, and 18 gastrectomies per year.

METHODS

Between 1988 and 2002, 1,032 patients underwent gastrectomy for gastric cancer in Verona, Siena, and Padua. D1, D2, and D3 lymphadenectomy were performed, respectively, in 228, 584, and 220 cases.

RESULTS

The median number of retrieved lymph nodes was 14 (interquartile range 9-18.75) after D1, 29 (21-38) after D2, and 46.5 (37-57) after D3. Fewer than 15 nodes were retrieved in 54.5%, 6.2%, and 1.4% of cases undergoing, respectively, D1, D2, and D3. Adjacent organ removal was rare during D1 (splenectomy: 6.1%, splenopancreasectomy: 1.8%), and quite common during D3 (11.4%, 11.4%). Forty patients (3.9%) died postoperatively. Neither postoperative morbidity nor mortality was significantly associated with extension of lymphadenectomy.

CONCLUSION

We conclude that at least D2 lymphadenectomy is necessary to achieve adequate disease staging (>or=15 nodes retrieved). Spleen and pancreas tail are more frequently removed during D3, but this removal is not associated with higher postoperative morbidity or mortality.

Impact of recent legislative bills regarding clinical research on Italian ethics committee activity

AIMS AND BACKGROUND

The present work assessed the impact of two decrees on ethics committees in Italy, aimed at bringing the national laws on the conduct of clinical trials into line with the rest of the EC, and regulating and facilitating not-for-profit research.

MATERIAL AND METHODS

Prospectively collected data from an Italian multicentre study were examined with respect to the ethics review process. Administrative and time elements of the review process were audited. Main outcome measures were time between the application submission and the ethics committee definitive opinion, type and number of application submission forms, number of ethics committees that refused fee exemption, and time between the ethics committee approval and the administrative authorisation.

RESULTS

A total of 134 local research ethics committees (LRECs) were approached. Application submission procedures and application forms varied greatly; paper submission was mandatory. The median time from submission to approval was 72 days. Only two LRECs refused the fee exemption. The median time from LREC approval to administrative agreement was 50 days and only 9.6% of local authorities came to a verbal agreement with the sponsor.

CONCLUSIONS

Italian LRECs are still not sufficiently efficient in complying with the Directive 2001/20/EC requirement (60 days). Better coordination of LRECs work is needed although the optimal level of coordination between them is still not known. In the meantime, national guidelines are needed concerning the application of Directive 2001/20/EC. The behaviour of Italian LRECs towards not-for-profit research was excellent although only the fee exemption was requested.

Proximal colon cancer in patients aged 51-60 years of age should be tested for microsatellites instability. A comment on the Revised Bethesda Guidelines

PURPOSE

The Bethesda guidelines suggest to perform microsatellite instability (MSI) test in early onset rectal cancer and not in patients>50 years with proximal colon cancer. The aim of the study was to evaluate whether the risk of high MSI (MSI-H) is greater in proximal colon cancer of patients 51-60 years old than in early-onset rectal cancer.

METHODS

Consecutive colorectal cancer (CRC) patients were evaluated. Tumor location, cancer family history, MSI status and histology were recorded. Mutations in MLH1/MSH2 were investigated in MSI-H tumors. Patients were subdivided into groups: group A, proximal colon cancer patients 51-60 years old and groups B, C and D, patients<or=50 years old, with rectal cancer, proximal and distal colon cancer, respectively.

RESULTS

Out of 409 CRC patients evaluated, 48 (12%) showed tumors with MSI-H. No MSI-H tumors were found in distal and rectal tumors of patients at sixth decade of life. Group A included 27 patients, eight (29.7%) MSI-H cancers, four missense mutations in MLH1/MSH2; groups B, C and D included 26, 11 and 11 patients with two (7.7%), two (18%) and two (18%) MSI-H cancers, respectively. One missense mutation on MSH2 in group B, one pathogenetic mutation on MSH1 in group C and one pathogenetic mutation on MSH2 in group D were found. Tumors of group A showed an increased probability to have MSI-H if compared to those of group B (OD=4.907, p=0.043).

CONCLUSIONS

The Bethesda criteria should be broadened to include patients 51-60 years old with proximal colon cancer.

Clinical impact of false-negative sentinel lymph nodes in breast cancer

AIMS

To evaluate the incidence of false-negative (FN) sentinel lymph node (SLN) cases, their correlation with a series of clinico-pathologic parameters and their impact on adjuvant treatment indications and on clinical axillary relapse in the setting of a multicentric clinical trial comparing SLN biopsy with axillary lymph node dissection (ALND).

METHODS

A series of 697 patients with primary breast cancer < or = 3 cm were randomized to SLN biopsy associated with ALND (ALND arm) or to SLN biopsy followed by ALND only if the SLN was metastatic (SLN arm). The FN SLN rate was assessed in the ALND arm. A series of 11 clinico-pathological parameters were tested for a possible association with FN results. The indications for adjuvant treatments were evaluated by considering both the FN nodal stages, as indicated by the SLN, and the true positive axillary status, as indicated by completion ALND. The occurrence of clinically evident axillary recurrences was evaluated in the two arms.

RESULTS

The FN rate was 16.7%. Of the clinico-pathologic parameters tested, only a tumour size < or = 2 cm and the presence of a single metastatic axillary node was significantly associated with a risk of FN (p = 0.033 and p = 0.018, respectively). The FN SLN would have led to different adjuvant therapy indications in 12/18 cases. At 56 months, no clinically evident axillary nodal recurrences were present in the ALND arm patients, whereas one case of axillary recurrence was detected in the SLN arm patients.

CONCLUSIONS

FN SLN biopsy is not uncommon, especially in the presence of a small primary tumour with a single nodal metastasis. An FN finding can lead to less than optimal adjuvant treatment. However, the clinical impact of FN in terms of axillary recurrence at 56 months was minimal.

Association of p53 polymorphisms and colorectal cancer: modulation of risk and progression

OBJECTIVES

p53 Gene variants BstUI RFLP at codon 72 in exon 4, 16bp tandem repeat in intron 3 and MspI RFLP in intron 6, which code for two functionally different protein isoforms, have been shown to modulate susceptibility to different types of human neoplasms.

METHODS

p53 genotype was assessed in 90 CRC patients, 321 age-matched controls and 322 centenarians.

RESULTS

The p53 codon 72 arginine, the p53 16bp deletion, and the MspI RFLP were significantly more frequent in CRC patients in comparison to the controls and to the centenarians (odd ratio 1.44 and 1.93). In the CRC group, the BstUI RFLP polymorphism was the more frequent combination (62.2%), and it was significantly associated with highly infiltrating (p<0.01), poorly differentiated (p<0.01), and metastatic (p<0.05) tumours. Our findings indicate that the p53 codon 72 polymorphisms are associated with a higher risk of CRC and are associated with more advanced and undifferentiated tumours.

Prediction of rectal lymph node metastasis by pelvic computed tomography measurement

AIM

Rectal cancer staging represents a crucial step to select the best treatment for this tumour. Particularly after neo-adjuvant chemoradiotherapy (CRT), it may influence the surgical procedure (e.g. radical resection vs. local excision). The aim of this study was to determine the best lymph node size cut-off at computed tomography (CT) to predict nodal metastasis in rectal cancer patients with and without preoperative CRT.

METHODS

A consecutive series of patients operated on for primary mid-low rectal adenocarcinoma, all staged with pelvic CT scan, were subdivided as follows: those who underwent surgery alone treatment without CRT (Group A) and those who underwent preoperative CRT (Group B). All CT scans were re-viewed by a single radiologist and, based on the lymph node size, findings were compared with pathologic lymph node status (pN). At each lymph node size cut-off value, the following were calculated: accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). The best cut-off value was defined as having an accuracy >or=70% with the highest NPV.

RESULTS

The study population consisted of 162 patients: Group A (n=52) and Group B (n=110). Patients classified as pN-positive (n=45) had a higher number of and larger sized lymph nodes by CT scan than patients classified as pN-negative (n=117). The cut-off values with an accuracy >or=70% ranged between 7 and 11 mm in Group A and between 9 and 14 mm in Group B. The cut-off with the best NPV was 7 mm for Group A and 10mm for Group B.

CONCLUSIONS

Acknowledging the limitations of the dimensional criterion, lymph node size cut-off values found in our study may be useful for planning rectal cancer treatment using CT scan.

Hepatic arterial infusion (HAI) compared to systemic chemotherapy for the treatment of unresectable liver metastases from colorectal carcinoma: A systematic review and meta-analysis of randomized controlled trials

14519

Background: The treatment of unresectable liver confined metastatic disease from colorectal cancer is a challenging issue. Although locoregional treatments such as HAI claim the advantage of delivering higher doses of anticancer agents directly into the affected organ, the evidence for benefit in terms of overall survival (OS) is conflicting. We aimed to quantitatively summarize the results so far described in randomized trials comparing HAI to systemic chemotherapy. Methods: To date, ten randomized controlled trials (RCT) have been published, for a total of 1,277 patients enrolled. Seven RCT (n=1,098) enrolling at least 50 patients per arm (the minimum sample size required to achieve a type II error lower than 20%) were considered for OS meta-analysis, which was based on the inverse of variance method. For tumor response rates, hazard ratios (HR) and their 95% confidence intervals (CI) were obtained from raw data; for OS, HR and CI were obtained from reported Cox model survival analyses or were calculated from Kaplan-Meier survival curves according to the Parmar method. Results: HAI regimens were based on floxuridine (FUDR) in nine out of ten RCT, while in one case 5-fluorouracil (5FU) + leucovorin (LV) were used. Systemic chemotherapy consisted of FUDR, 5FU, 5FU + LV, or a miscellany of 5FU and best supportive care in three, one, four and two studies, respectively. Tumor response and median OS were better in the HAI arm in eight and three RCT, respectively. At meta-analysis, median tumor response rate was 38.84% and 17.30% for HAI and systemic chemotherapy, respectively (HR: 2.24, CI: 1.80- 2.81; P < 0.0001); on average, median OS was 16.04 and 12.64 months, respectively (HR: 0.83, CI: 0.58–1.19; P value 0.30). Conclusions: Although HAI regimens are followed by significantly higher tumor response rates, no OS advantage can be demonstrated for this locoregional treatment as compared to systemic chemotherapy. Since HAI has been so far compared to systemic chemotherapy regimens not containing modern and more effective antineoplastic agents (e.g. oxaliplatin, irinotecan), these findings do not support the clinical or investigational use of FUDR-based HAI.

No significant financial relationships to disclose.

Identification of patients who most benefit from hepatic arterial infusion (HAI) combined or not with systemic chemotherapy for the treatment of unresectable colorectal liver metastases

14565

Background: Although locoregional treatments such as hepatic arterial infusion (HAI) claim the advantage of delivering higher doses of anticancer agents directly into the affected organ, there is substantial lack of evidence for benefit in terms of overall survival (OS). To test the hypothesis that systemic chemotherapy affects OS of patients with unresectable colorectal liver metastases treated with HAI. Furthermore, we investigated patient- and tumor-related predictive factors that might identify patients who most benefit from HAI regimen. Methods: In this retrospective study, 153 consecutive patients treated at our institution were considered. In group-A (n=72), patients were treated with HAI alone (floxuridine (FUDR) 0.2 mg/Kg + leucovorin (LV) 4 mg/m2 + desamethasone 20 mg 14 days/month) between 1994 and 1999. In group-B (n=81), patients were treated with the same HAI regimen combined with systemic chemotherapy (5-fluorouracil (5FU) 450 mg/m2 + LV 20 mg/m2) between 1999 and 2003. Results: No difference in OS was observed between group-A and group-B (median OS: 18.0 and 19.1 months, respectively). Considering all patients (group A + group B), low tumor load was associated with a better tumor response rate, but none of the traditional clinico-pathological prognostic factors correlated with OS. Median OS was better in patients with less than 50% of liver parenchyma involvement (21.3 vs 13.2 months; P<0.0001) as well as in responders (complete or partial response) versus non-responders (24.4 vs 13.4 months; P<0.0001). The combination of low tumor load with good tumor response to HAI was the only variable retained at multivariate analysis, and identified a subgroup of patients with a very favorable clinical outcome (median survival: 34.2 months; hazard ratio: 0.347, CI: 0.249–0.564, P< 0.0001). Conclusions: Combination with 5FU+LV systemic chemotherapy did not lead to an OS benefit over FUDR-based HAI alone. The identification of tumor response predictors is urgently needed, as it would lead to the tailored treatment of patients with low load but unresectable metastatic liver disease who most benefit from HAI therapy.

No significant financial relationships to disclose.

Personalized therapy for metastatic colorectal cancer: A closer possibility?

4131

Background: Colorectal cancer (CRC) is the second leading cause of cancer related death in the Western world, and survival rate is closely associated with the development of metastases. Personalized targeted therapies promise to have a dramatic impact on the treatment of cancer over the next decade. The molecular fingerprint of a patient’s tumor is the basis for specific targeted therapy. Most often, we are not measuring what we are treating. If we choose therapy based on the primary tumor, but we are treating the metastasis, we are likely giving the wrong therapy if the two microenvironments are not equivalent. In this study we employed reverse phase protein microarrays (RPPA) to compare the protein kinases signal pathway derangements in the primary CRC and in its synchronous liver metastasis. Methods: Pure cell populations of 34 cases of patient-matched CRC and hepatic metastases (collected at the same surgical time) were isolated through laser capture microdissection and then lysed. The lysed cells were evaluated using RPPA technology that allowed us to analyze the activation status of 80 different kinases. Data analysis was performed using commercially available software. Results: Of the 80 kinases only 20 endpoints were significantly (p< 0.05) altered between the two populations. These endpoints were contained within just a few signaling pathways, including the PI3K-AKT prosurvival pathway and the c-kit/PDGFr/c-abl growth factor pathway. We noted a significant increase in phosphorylation of AKT along with a decrease in phosphorylation of PTEN in the liver metastasis compared to the matched primary tumors. This is in keeping with what is known about AKT since phosphorylation of PTEN serves to destabilize the protein, which serves as a natural upstream suppressor of AKT kinase. Conclusions: Specific cell signaling pathways, such as the PI3K-AKT and the c-kit/PDGFr/c-abl growth factor signaling pathway, are significantly altered and activated in hepatic metastasis compared to the primary colorectal site. Since the data reveals elevation in kinase activity increases on a pathway-wide level, a rational hypothesis can be developed whereby combinations of drugs such as an AKT- mTOR inhibitor and/or Gleevec may be an effective and novel therapeutic strategy for the treatment of metastatic CRC.

No significant financial relationships to disclose.

The prognostic value of N-ratio in patients with gastric cancer: validation in a large, multicenter series

AIMS

The proportion between metastatic and examined lymph nodes (N-ratio) has been proposed as an independent prognostic factor in patients with gastric cancer. In the present work we validated the reliability of N-ratio in a large, multicenter series.

PATIENTS AND METHODS

We retrospectively reviewed the data of 1853 patients who underwent radical resection for gastric carcinoma. Survival of patients with >15 (Group-1, n=1421) and those with < or =15 (Group-2, n=432) lymph nodes examined was separately analyzed in order to evaluate the influence of lymph node dissection on disease staging. N-ratio categories (N-ratio 0, 0%; N-ratio 1, 1-9%; N-ratio 2, 10-25%; N-ratio 3, >25%) were determined by the best cut-off approach.

RESULTS

At multivariate analysis, N-ratio (but not TNM N-category) was retained as an independent prognostic factor both in Group-1 and Group-2 (HR for N-ratio 1, N-ratio 2 and N-ratio 3=1.67, 2.96 and 6.59, and 1.56, 2.68 and 4.28, respectively). After a median follow-up of 45.5 months, the 5-year overall survival rates of TNM N0, N1 and N2 patients were significantly different in Group-1 vs Group-2. This was not the case when adopting the N-ratio classification, suggesting that a low number of excised lymph nodes can lead to patients being understaged using the N-category, but not N-ratio. Moreover, N-ratio identified subsets of patients with significantly different survival rates within TNM N1 and N2 categories in both groups.

CONCLUSIONS

N-ratio is a simple and reproducible prognostic tool that can stratify patients with gastric cancer, including those cases with limited lymph node dissection. These data support the rationale to propose the implementation of N-ratio into the current TNM staging system.