Outcomes of Rural Men with Breast Cancer: A Multicenter Population Based Retrospective Cohort Study

Background: Breast cancer is rare in men. This population-based study aimed to determine outcomes of male breast cancer in relation to residence and other variables. Methods: In this retrospective cohort study, men diagnosed with breast cancer in Saskatchewan during 2000–2019 were evaluated. Cox proportional multivariable regression analyses were performed to determine the correlation between survival and clinicopathological and contextual factors. Results: One hundred-eight eligible patients with a median age of 69 years were identified. Of them, 16% had WHO performance status ≥ 2 and 61% were rural residents. The stage at diagnosis was as follows: stage 0, 7%; I, 31%; II, 42%; III, 11%; IV, 8%. Ninety-eight percent had hormone receptor-positive breast cancer. The median disease-free survival of urban patients was 97 (95% CI: 50–143) vs. 64 (46–82) months of rural patients (p = 0.29). The median OS of urban patients was 127 (94–159) vs. 93 (32–153) months for rural patients (p = 0.27). On multivariable analysis, performance status ≥ 2, hazard ratio (HR) 2.82 (1.14–6.94), lack of adjuvant systemic therapy, HR 2.47 (1.03–5.92), and node-positive disease, HR 2.32 (1.22–4.40) were significantly correlated with inferior disease-free survival in early-stage invasive breast cancer. Whereas stage IV disease, HR 7.8 (3.1–19.5), performance status ≥ 2, HR 3.25 (1.57–6.71), and age ≥ 65 years, HR 2.37 (1.13–5.0) were correlated with inferior overall survival in all stages. Conclusions: Although residence was not significantly correlated with outcomes, rural men had numerically inferior survival. Poor performance status, node-positive disease, and lack of adjuvant systemic therapy were correlated with inferior disease-free survival.

Early discontinuation of adjuvant chemotherapy in patients with early-stage pancreatic cancer correlates with inferior survival: A multicenter population-based cohort study

Background

The current study aimed to determine the association between timing and completion of adjuvant chemotherapy and outcomes in real-world patients with early-stage pancreatic cancer.

Methods

In this multi-center cohort study patients with early-stage pancreatic cancer who were diagnosed from 2007–2017 and underwent complete resection in the province of Saskatchewan were examined. Cox proportional multivariate analyses were performed for correlation with recurrence and survival.

Results

Of 168 patients, 71 eligible patients with median age of 69 years and M:F of 37:34 were identified. Median time to the start of adjuvant therapy from surgery was 73 days. Of all patients, 49 (69%) patients completed adjuvant chemotherapy and 22 (31%) required early treatment discontinuation. Median recurrence-free survival of patients who completed treatment was 22 months (95%CI:15.8–28.2) vs. 9 months (3.3–14.7) if treatment was discontinued early (P<0.001). Median overall survival of those who completed treatment was 33 (17.5–48.5) vs. 16 months (17.5–48.5) with early treatment discontinuation (P<0.001). In the multivariate analysis, treatment discontinuation was significantly correlated with recurrent disease, hazard ratio (HR), 2.57 (1.41–4.68), P = 0.002 and inferior survival, HR, 2.55 (1.39–4.68), P = 0.003. No correlation between treatment timing and survival was noted.

Conclusions

Early discontinuation but not the timing of adjuvant chemotherapy correlates with inferior outcomes.

Outcomes of patients with small intestine adenocarcinoma (SIA) in a Canadian province: A population-based cohort study

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Background: SIA is a rare cancer. Limited data is available about clinicopathological factors and interventions that correlate with its outcomes. The current study aims to determine outcomes of patients with SIA who were diagnosed in a Canadian province. Methods: In this retrospective population-based cohort study patients with biopsy proven SIA diagnosed during 2008-2017 in the province of Saskatchewan were assessed. A Cox Proportional multivariate regression analysis was performed to determine correlation between survival and exploratory factors. Results: 112 eligible patients with median age of 73 yrs and M:W 53: 59 were identified. 75% had a comorbid illness, 34% had a secondary cancer and 45% had WHO performance status (PS) < 2. Of 112 patients, 51 (46%) had early-stage disease and 61 (54%) had advanced-stage disease. Median neutrophil: lymphocyte (NLR) was 4.5. The median overall survival (mOS) in relation to stage of the disease were as follow: stage 1, 59 months, stage 2, 30 months, stage 3, 20 months and stage 4, 3 months (P < 0.001). The patients with early-stage disease had mOS of 36.0 months (95% CI: 8.0-64.0) vs. 3.0 months (1.74-4.26) with advanced disease (P < 0.0001). Of 21 patients with stage 3 disease their median disease-free survival was 26 months (23.1-28.9) with chemotherapy vs. 4 months (0.0-9.1) with no chemotherapy, p = 0.04. Patients with stage 4 disease who had surgery and or chemotherapy had mOS of 18 months (13.70-23.32) vs. 4 months (2.20-5.82) with chemotherapy alone p = 0.03. On univariate analysis age ≥70 yrs, WHO PS > 1, stage 4 disease, low albumin, elevated creatinine, high alkaline phosphatase, duodenal cancer, lack of surgery, and NLR of > 4.50 were significantly correlated with inferior survival. On multivariate analysis stage 4 disease, HR, 3.20 (95%CI:1.84-5.40), WHO PS > 1, HR, 2.22 (1.42-3.45), no surgery, HR, 2.10 (1.25-3.50), and NLR > 4.5, HR, 1.72 (1.10-2.71) were significantly correlated with inferior survival. Conclusions: Most patients with SIA were diagnosed with advanced-stage. In addition to advanced-stage disease and poor PS, lack of surgery and baseline LNR of > 4.5 were significantly correlated with inferior survival.

Three dimensional microelectrodes enable high signal and spatial resolution for neural seizure recordings in brain slices and freely behaving animals

Neural recordings made to date through various approaches—both in-vitro or in-vivo—lack high spatial resolution and a high signal-to-noise ratio (SNR) required for detailed understanding of brain function, synaptic plasticity, and dysfunction. These shortcomings in turn deter the ability to further design diagnostic, therapeutic strategies and the fabrication of neuro-modulatory devices with various feedback loop systems. We report here on the simulation and fabrication of fully configurable neural micro-electrodes that can be used for both in vitro and in vivo applications, with three-dimensional semi-insulated structures patterned onto custom, fine-pitch, high density arrays. These microelectrodes were interfaced with isolated brain slices as well as implanted in brains of freely behaving rats to demonstrate their ability to maintain a high SNR. Moreover, the electrodes enabled the detection of epileptiform events and high frequency oscillations in an epilepsy model thus offering a diagnostic potential for neurological disorders such as epilepsy. These microelectrodes provide unique opportunities to study brain activity under normal and various pathological conditions, both in-vivo and in in-vitro, thus furthering the ability to develop drug screening and neuromodulation systems that could accurately record and map the activity of large neural networks over an extended time period.

Comparison of Perioperative Chemotherapy versus Postoperative Chemoradiotherapy for Operable Stomach Cancer: A Western Canadian Province Experience

Background: The standard approaches for resectable stomach cancer are postoperative chemoradiotherapy (PCR) or perioperative chemotherapy (PC). Limited evidence is available regarding the superiority of one of the two approaches. We aimed to compare the survival of patients with operable stomach cancer who were treated with PC or PCR. Methods: In this retrospective cohort study, patients with operable stomach cancer diagnosed between 2005–2015 in the province of Saskatchewan were identified and, based on type of treatment, were placed into PCR and PC groups. A Cox proportional multivariate analysis was performed to assess independent prognostic variables, including survival advantage of PC over PCR. Results: A total of 88 eligible patients with a median age of 66 (56–71) and a male to female ratio of 1:0.44 were identified. Seventy-three (83%) patients had pathologically node positive disease. Sixty-seven (76%) patients received PCR, while 21 (24%) patients received PC. The median overall survival of the whole group was 34 months, with 38 months (95% CI 24.6–51.3) in the PCR group vs. 30 months (14.3–45.7) in the PC group (p = 0.29). Median relapse-free survival was 34 months (20.7–47.3) in the PCR group vs. 23 months (6.7–39.3) in the PC group (p = 0.20). Toxicities were comparable. On multivariate analysis, T ≥ 3 tumor (HR, 3.57 (1.39–8.56)), neutrophil to lymphocyte ratio (LNR) > 2.8 (HR, 1.85 (1.05–3.25)), and positive resection margins (HR, 1.89 (1.06–3.37)) were independently correlated with inferior survival. Conclusions: This well-designed population based cohort study suggests a lack of survival benefit of PC over PCR. Both treatment options remain viable approaches for resectable stomach cancer.

Second-line Chemotherapy Prolongs Survival in Real World Patients With Advanced Biliary Tract and Gallbladder Cancers: A Multicenter Retrospective Population-based Cohort Study

BACKGROUND

Limited evidence is available regarding the survival benefit of second-line therapy in real world patients with advanced biliary tract and gallbladder cancer. Until very recently, there was a lack of randomized clinical trials to address this important question. In this multicenter population-based cohort study, the authors evaluated whether second-line therapy improves the survival of real world patients with advanced biliary tract and gallbladder cancer.

METHODS

Patients with biopsy-proven advanced biliary tract and gallbladder cancer who were diagnosed during the period of 2006 to 2015 and had received first-line chemotherapy were assessed. Cox proportional multivariate analysis was performed to determine the survival benefit of second-line therapy.

RESULTS

One hundred thirty-six eligible patients with a median age of 66 years and male:female ratio of 1:1.34 were identified. Sixty-eight percent of patients had metastatic disease. Primary tumor sites were as follows: gallbladder 31%, intrahepatic cholangiocarcinoma 36%, extrahepatic bile duct 23%, and ampullary cancer 10%. Overall, 37% of patients received second-line therapy. The median overall survival of the treatment group was 17 months (95% confidence interval [CI]: 12.5-21.5) compared with 7 months (95% CI: 5.3-8.7) in the control (P<0.0001). Patients who received combination chemotherapy had a median overall survival of 20 months (14.0-26.1) compared with 17 months (13.5-20.5) if they received single-agent second-line therapy (P=0.73). Multivariate analysis of second-line therapy, hazard ratio: 0.55 (95% CI: 0.36-0.83) and neutrophil to lymphocyte ratio >2, HR: 1.10 (1.05-1.15) showed a significant correlation with survival.

CONCLUSIONS

This well-designed population-based retrospective cohort study suggests that second-line chemotherapy improves survival of real world patients with advanced biliary tract and gallbladder cancers and should be offered to the patients who are potential candidates for chemotherapy.

Current status of systemic therapy in hepatocellular cancer

Hepatocellular cancer (HCC) is a common cancer and an important cause of cancer-related death globally. Although surgery is the primary curative treatment, most patients at diagnosis are not surgical candidates and are treated with liver-directed therapy and or systemic therapy. Over the past decade, the systemic treatment options for patients with advanced HCC have evolved. This paper reviews recent progress in systemic therapy and the results of major clinical trials involving novel compounds in patients with HCC. A literature search was performed using keywords related to HCC and systemic therapy. The evidence shows that at the present time an effective adjuvant systemic therapy is not available for patients with early-stage HCC following surgery. In patients with advanced HCC, in addition to sorafenib at least four other targeted agents and several immune checkpoint inhibitors, alone or in combination have been shown to be associated with improved progression-free and overall survival. The optimal sequence of agents, is currently not known, and is determined by patient characteristics, toxicities profile, patients and physicians preference. The future identification of novel active agents and predictive biomarkers are vital to personalize systemic therapy in HCC.

The prognostic and predictive role of 21-gene recurrence scores in hormone receptor-positive early-stage breast cancer

Over the past two decades, gene expression profiling of breast cancer has emerged as an important tool in early-stage breast cancer management. The approach provides important information on underlying biological mechanisms, breast cancer classification, future risk potential of developing recurrent metastatic disease, and provides beneficial clues for adjuvant chemotherapy in hormone receptor (HR) positive breast cancer. Of the commercially available genomic tests for breast cancer, the prognostic and predictive value of 21-gene recurrence score tests have been validated using both retrospective data and prospective clinical trials. In this paper, we reviewed the current evidence on 21-gene expression profiles for HR-positive HER2-negative early-stage breast cancer management. We show that current evidence supports endocrine therapy alone as an appropriate adjuvant systemic therapy for approximately 70% of women with HR-positive, HER2-negative, node-negative breast cancer. Evolving evidence also suggests that 21-gene recurrence scores have predictive values for node-positive breast cancer and that chemotherapy can be avoided in more than half of women with nodes 1 to 3 positive HR-positive breast cancer. Furthermore, retrospective data also supports the predictive role of 21-gene recurrence scores for adjuvant radiation therapy. A prospective trial in this area is ongoing.

Rate of conversion from unresectable to resectable metastatic colorectal cancer (mCRC) in real-world patients (RWP) treated with FOLFIXIRI ± bevacizumab: A population-based retrospective cohort study

21

Background: Recent evidence from randomized trials suggests that FOLFOXIRI (5FU, oxaliplatin, and irinotecan) ± bevacizumab is associated with higher response rates with a potential for conversion of unresectable to resectable disease in mCRC. Yet limited evidence is available about efficacy and safety of this regimen in RWP with mCRC. The current study aims to evaluate conversion rate and safety of FOLFOXIRI ± bevacizumab in RWP with unresectable mCRC. Methods: Each year about 175 patients are diagnosed with mCRC in Saskatchewan. Patients who were diagnosed with unresectable mCRC between Jan 2015 to Dec 2018 and received FOLFOXIRI ±bevacizumab were assessed. Kaplan Meier survival methods and log rank test were performed. Logistic regression analysis was performed to assess factors correlate with conversion. Results: 28 eligible patients with median age of 51 yrs (IQR:39-60) and M:F of 11:16 were identified. 42% patients had a comorbid illness, and 43% had WHO performance status of 0. 39% had rectal cancer, 46% had extrahepatic disease and 46% had bilobar liver metastases. 58% patients had a positive response to therapy, 60% had grade 3/4 toxicity & 32% required hospital admission. No treatment-related mortality was noted. 54% patients underwent metastasectomy (liver 73%, peritoneum and or ovaries 20%, lung 6%). 68% had primary tumor resection, 29% received rectal radiation, 21% had ablation and 18% had second surgery for recurrence. At 4 years 50% patients are alive. Median progression free survival of patients who underwent surgery is 18 (95%CI:11.3-24.7) vs. 11 months (4-18.1) without surgery (P = 0.28). Median overall survival of patients with surgery is 33 (17.5-48.5) vs. 16 months (8.3-23.7) without surgery (P = 0.03). Positive response to treatment is correlated with conversion (odd ratio 21.7, p = 0.002). Conclusions: In the real world setting younger patients with good performance status received FOLFIRINOX ± bevacizumab. Despite high rates of toxicity, more than half of patients were able to undergo surgery. A positive response to treatment significantly correlates with metastasectomy.

Effects of early discontinuation of adjuvant chemotherapy (EDAC) and the timing of treatment on outcomes in patients with early-stage pancreatic cancer (ESPC): Result from a population-based retrospective cohort study

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Background: Although evidence suggests that a delay in initiation of adjuvant chemotherapy (AC) results in inferior outcomes in some cancers, little is known about its detrimental effects in patients with ESPC. Moreover, it is not known if EDAC has been associated with high risk of recurrence and poor survival. The current study aims to determine association between timing and completion of AC and outcomes in ESPC. Methods: Patients with ESPC who were diagnosed from Jan 2007 to Dec 2017 and underwent complete resection in the province of Saskatchewan were examined. Kaplan Meier methods and log rank tests were performed for survival analyses. Cox proportional multivariate analyses were performed for correlation with recurrence and survival. Results: A total 168 patients with ESPC were identified. 97 (57%) patients were excluded as they did not receive AC, were found to have metastatic disease, did not have curative surgery or had received preoperative chemotherapy. Of 71 eligible patients with median age of 69 years (IQR: 57-73), 52% were male, 31% had WHO performance status of 0 and 92% had a comorbid illness. 78% had pancreatic head tumor, 66% had T3 tumor and 63% had node-positive disease. Median time to start of AC from surgery was 73 days (IQR: 59-89). 32% were started AC within 60 days of surgery. 89% received single-agent chemotherapy and 25% received adjuvant radiation. 69% completed planned treatment. Median time to recurrence in group which completed treatment was 22 months (95%CI:15.8-28.2) vs. 9 months (3.3-14.7) if treatment was discontinued early (P < 0.001). Median overall survival of the group that completed treatment was 33 months (17.5-48.5) vs. 16 months (17.5-48.5) if it was stopped early (P < 0.001). On multivariate analysis, EDAC was significantly correlated with recurrent disease (HR = 3.0; 1.6-5.5), P = 0.0001 and inferior survival (HR = 3.2; 1.68-6.12), P < 0.001. No correlation between AC timing and survival was noted. Conclusions: Although timing of AC does not correlate with inferior outcomes, EDAC has been associated with high risk of recurrence and inferior survival in ESPC.

Social and contextual factors and their relationship with the use of palliative chemotherapy in patients with metastatic colorectal cancer (mCRC): A retrospective cohort study

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Background: Although there is evidence that social and contextual factors such as living alone are associated with outcomes in cancer patients, little is known about their influence on the use of palliative chemotherapy in mCRC. We previously reported various patient-and tumor-related factors that correlate with the use of palliative chemotherapy in mCRC (Oncology. 2015;88:289). In this study we examine social and contextual factors including marital status, having children and distance to cancer center for their association with the use of chemotherapy in patients with mCRC. Methods: A cohort of 569 patients with mCRC diagnosed from 2006-2010 in Saskatchewan was evaluated. Logistic regression analyses were performed to assess relationship between the use of chemotherapy and various variables. Results: Median age was 69 yrs (IQR 59-77) and M:F was 59:41. 326 (57%) patients received chemotherapy. Significant differences were noted between the chemotherapy vs. no chemotherapy groups with respect to median age (62 vs. 76 year, p < 0.001), WHO performance status (PS) > 1 (18 vs. 58%, p < 0.001), comorbid illness (24 vs 63%, p < 0.001), low albumin (61 vs. 89%, p < 0.001), anemia (61 vs. 87%, p < 0.001), elevated alkaline phosphatase (53 vs. 84% < 0.001), elevated creatinine (6 vs. 11%, p = 0.025), hyponatremia (20 vs. 14%, p = 0.03), primary tumor resection (61 vs 47%, p = 0.001), metastasectomy (21 vs. 9%, p < 0.001), mean distance to cancer center (98.7±113.6 vs. 127.8±124.6 km, p < 0.001), married/partnered (67 vs 33%, p < 0.001), and having children (64 vs. 36%, p < 0.001), respectively. On multivariate logistic regression analysis after adjustment of other variables, WHO PS > 1 (HR 5.1; 95%CI: 3.1-81.), not having children (3.3, 1.78-6.2, < 0.001), elevated alkaline phosphatase (HR 2.9; 95%CI: 1.8-4.8), and low albumin (HR 2.2; 95%CI: 1.2-3.8), were correlated with low rates of chemotherapy. Marital status or travel distance did not correlate with use of chemotherapy. Conclusions: Our results show that use of chemotherapy in patients with mCRC significantly varies in those with and without children. Future study are required to explore this difference.

Primary tumor location and survival in general population with metastatic colorectal cancer (mCRC)

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Background: Recent evidence from clinical trials suggests that location of the primary tumor in patients with mCRC correlates with differential outcomes and patients with tumors originating in the right side of colon have inferior survival. This large population-based cohort study using individual patient data was performed to confirm this findings in general population with mCRC. Methods: A cohort of 1947 patients who were diagnosed with synchronous mCRC from 1992-2010 was studied. Ascending and transverse colon cancers were defined as right-sided tumors (RT) and remainder tumors were define as left-sided tumors (LT). Cox proportional multivariate analyses were done to determine prognostic significance of primary tumor location and to adjust other prognostic variables including age, Charlson comorbid index (CCI) and WHO performance status (PS) in patients treated with chemotherapy. Results: Median age was 70 years (IQR: 60-78) and M:F was 1.3:1. Mean CCI was 9.7±1.4 and 29% had WHO PS of > 1. 770 (39%) patients had RT and 37% had stage IVb disease. 908 (47%) received chemotherapy and of those 44% received modern chemotherapy. Significant differences were noted between the groups with RT and LT with respect to age, WHO PS, CCI, liver metastases, mucinous tumor, grade, smoking history, and primary tumor resection. Median overall survival of patients with RT was 14 (95%CI: 12.7-15.3) months compared with 20.5 (95%CI: 18.5-22.5) of patients with LT (p < 0.001). On multivariate analysis following variables were correlated with inferior survival: Right-sided tumors, hazard ratio (HR) 1.40 (95%CI: 1.20-1.60); no primary tumor resection, HR 1.60 (95%CI: 1.32-1.90); no metastasectomy, HR 2.40 (95%CI: 1.90-2.90); not using modern chemotherapy, HR 1.52 (95%CI: 1.31-1.80); leukocytosis, HR 1.44 (95%CI: 1.28-1.73); elevated CEA, HR 1.54 (95%CI: 1.30-1.90); WHO PS > 1, HR 1.30 (95%CI: 1.10-1.55); and stage IVb disease, HR 1.50 (95%CI: 1.17-1.86). Tests for interaction were negative. Conclusions: Our results confirm that patients with RT who received chemotherapy have inferior survival independent of other known prognostic variables. Future studies are required to understand underlying pathophysiology.

Surgical Management of the Primary Tumor in Stage IV Colorectal Cancer: A Confirmatory Retrospective Cohort Study

BACKGROUND

Observational studies have suggested that patients with stage IV colorectal cancer who undergo surgical resection of the primary tumor (SRPT) have better survival. Yet the results are not confirmed in the setting of a randomized controlled trial. Lack of randomization and failure to control prognostic variables such as performance status are major critiques to the findings of the observational studies. We previously have shown that SRPT, independent of chemotherapy and performance status, improves survival of stage IV CRC patients. The current study aims to validate our findings in patients with stage IV CRC who were diagnosed during the period of modern chemotherapy.

METHODS

A cohort of 569 patients with stage IV CRC diagnosed during 2006-2010 in the province of Saskatchewan was evaluated. Cox regression model was used for the adjustment of prognostic variables.

RESULTS

Median age was 69 years (59-95) and M: F was 1.4:1. Fifty-seven percent received chemotherapy, 91.4% received FOLFIRI or FOLFOX & 67% received a biologic agent. Median overall survival (OS) of patients who underwent SRPT and received chemotherapy was 27 months compared with 14 months of the non-resection group (p<0.0001). Median OS of patients who received all active agents and had SRPT was 39 months (95%CI: 25.1-52.9). On multivariate analysis, SRPT, hazard ratio (HR):0.44 (95%CI: 0.35-0.56), use of chemotherapy, HR: 0.33 (95%CI: 0.26-0.43), metastasectomy, HR: 0.43 (95%CI: 0.31-0.58), second line therapy, HR: 0.50 (95%CI: 0.35-0.70), and third line therapy, HR: 0.58 (95%CI: 0.41-0.83) were correlated with superior survival.

CONCLUSIONS

This study confirms our findings and supports a favorable association between SRPT and survival in patients with stage IV CRC who are treated with modern therapy.

Prognostic significance of regional lymph nodes status in stage IV colorectal cancer

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Background: Lymph node involvement is one of the most important prognostic variables in early stage CRC and an indication for adjuvant therapy. However, the prognostic significance of regional nodal metastases and the ratio of metastatic to examined lymph nodes (LNR), in stage IV CRC remain unknown. The current study aims to determine prognostic importance of nodal status and LNR in patients with stage IV CRC who undergo primary tumor resection (PTR). Methods: Retrospective cohort study involving patients with synchronous metastatic CRC diagnosed in Saskatchewan, during 1992-2010 and underwent PTR. Cox Proportional multivariate analyses were performed to determine prognostic significance of nodal status and LNR. Results: 2,294 patients were diagnosed with synchronous metastatic CRC during the study period. Of those 1257 underwent PTR, 148 patients did not have information about nodal status and were excluded. Median age of 1109 eligible patients was 70 yrs (22-98) and M:F was 1.2:1. 26% patients had rectal cancer, 96% had T3/T4 tumor, and 82% had node positive disease. The median LNR was 0.36 (0-1.0). 54% received chemotherapy. Median overall survival of patients who had LNR of ≥ 0.36 and received chemotherapy was 29.7 months (95% CI: 26.6-32.9) compared with 15.6 months (13.6-17.6) with LNR of < 0.36 [p < 0.001]. On multivariate analyses, among prognostic variables use of any chemotherapy, HR: 2.36 (2.0-2.79); metastasectomy, HR: 1.95 (1.63-2.32); nodal status, HR 1.34 (1.14-1.59); LNR ≥0.36, HR: 1.59 (1.38-1.84); and T status, 1.23 (1.07-1.40) were correlated with survival. Test for interaction was positive for LNR and high grade cancer, HR: 1.17 (1.031-1.33). In a sub-cohort of patients who underwent metastasectomy both LNR using a cut-off of 0.36 and nodal status, independent of chemotherapy and other prognostic variables were correlated with survival, HR of 2.38 (95%: 1.64-3.47) for LNR ≥ 36 and 1.57 (95% CI: 1.05-2.34) for node positive disease. Conclusions: Our results suggest that regional nodal status and LNR are important prognostic factor independent of chemotherapy in stage IV CRC patients undergoing PTR. Future studies are required to elucidate the mechanism by which nodal status affect survival in stage IV CRC.

Time to first-line chemotherapy and travel distance to the cancer center and their relationship to subsequent-line therapies in stage IV CRC

724

Background: Second and third line therapies in stage IV colorectal (CRC) have been associated with significant improvement in survival. However, not all patients receive all available therapies. Delay in starting treatment and travel burden can affect patient access and use of future therapy. Little is known about time to first line chemotherapy (TC) and travel distance to cancer center (TD) and their relationship to future therapies in stage IV CRC. The study aims to determine relationship between TC and TD with second and subsequent line of therapies. Methods: A patients cohort diagnosed with synchronous stage IV CRC during 2006-2010 in the province of Saskatchewan, Canada was studied. Patients with ECOG performance status of > 1 or who did not receive chemotherapy were excluded. The logistic regression analyses were performed to assess relationship between TC and TD and subsequent line therapies. Results: 569 patients were diagnosed with synchronous stage IV CRC. 326 patients received first line chemotherapy (mostly FOLFIRI ± bevacizumab). Of 326 patients 62 with ECOG performance status (PS) > 1 were excluded. The median age of 264 eligible patients was 62 yrs (IQR:53-72). 61% were male and 38% had ECOG PS of 0. Mean Charlson score was 9±1.3. 24% underwent metastasectomy. Median TC was 77 days (IQR: 53-107) and median TD was 64.4 km (IQR:4.8-166). 42.8% patients had to travel > 100 km for their treatment. Of 326 patients 144 (55%) received future therapies. On multivariate analysis absence of comorbid illness (as per Charlson comorbid index), odd ratio (OR) 1.45 (95% CI: 1.19-1.77), no metastasectomy, OR 1.89 (1.03-3.46) and TD < 100 km, OR 1.69 (1.003-2.84) were correlated with the utility of 2ndand subsequent line therapies. Conclusions: Our result revealed that although time to first line chemotherapy did not correlate with future systemic therapies, travel distance to Cancer Center > 100 km was associated with low rate of second or subsequent line therapies in statge IV CRC patients with good performance status.

Surgical Resection of Primary Tumor in Asymptomatic or Minimally Symptomatic Patients With Stage IV Colorectal Cancer: A Canadian Province Experience

BACKGROUND

Surgical resection of the primary tumor in patients with stage IV colorectal cancer (CRC) remains controversial. Survival benefit reported in the literature has been attributed to the selection of younger and healthier patients with good performance status. We have recently reported that resection of the primary tumor improved survival of patients with stage IV CRC. In this study we examined survival benefit of surgery in patients with asymptomatic or minimally symptomatic primary tumor.

PATIENTS AND METHODS

A cohort of patients with stage IV CRC and asymptomatic or minimally symptomatic primary tumor, who were diagnosed during the period of 1992 to 2005, in the province of Saskatchewan Canada, was evaluated. The Kaplan-Meier method was used to determine survival. A multivariate Cox proportional hazard regression analysis was performed to determine prognostic importance of resection of primary tumor. A test for interaction was performed for resection of primary tumor and other important clinicopathological variables.

RESULTS

A total of 834 patients with a median age of 70 years (range, 22-93) and male:female ratio of 58:42 were identified. Among them 521 (63%) patients underwent surgery and 361 (43.3%) received chemotherapy. Patients who underwent surgery and received any chemotherapy had a median overall survival of 19.7 months (95% confidence interval [CI], 16.9-22.6) compared with 8.4 months (95% CI, 6.9-10.0) if they did not have surgery (P < .0001). In multivariate analysis, 5-fluorouracil-based chemotherapy (hazard ratio [HR], 0.43; 95% CI, 0.36-0.53), surgical resection of the primary tumor (HR, 0.47; 95% CI, 0.39-0.57), metastasectomy (HR, 0.48; 95% CI, 0.38-0.62), and second-line chemotherapy (HR, 0.72; 95% CI, 0.58-0.92) were correlated with superior survival. A test for interaction between ≥ 1 metastatic sites and surgery was significant, which suggests a larger benefit of surgery in patients with stage IVA disease.

CONCLUSION

Results of this large population-based cohort study suggest that resection of the primary tumor in asymptomatic or minimally symptomatic patients with stage IV CRC improved survival independent of other prognostic variables. The benefit was more pronounced in stage IVA disease.

Surgical management of the primary tumor in stage IV colorectal cancer: A validation study

675

Background: The observational studies have demonstrated superior survival of patients with stage IV CRC who undergo surgical resection of the primary tumor (SRPT). Yet the results are not confirmed in the setting of a randomized controlled trial. Lack of randomization and failure to control the prognostic variables that affect survival including performance status (PS) are the major critiques to the findings of observational studies. Our group has demonstrated that SRPT improves survival of stage IV CRC patients, who were diagnosed between 1992-2005, independent of age and PS (Cancer. 2014;120:683). The current study is undertaken to validate our findings in patients who are treated with modern chemotherapy. Methods: A cohort of 569 patients with stage IV CRC diagnosed between 2006-2010 in Saskatchewan was evaluated. Cox regression model was used to adjust survival for important prognostic variables. Results: Median age was 69 years (59-95) and M:F was 1.4:1. 35% had ECOG PS of >1. 313 (55%) patients underwent SRPT. Median followup time was 11 months (inter-quartile range 2-26). 57.3% received chemotherapy, 91.4% received FOLFIRI or FOLFOX and 67% received anti-EGFR inhibitors and or bevacizumab. Median overall survival (OS) of patients who had SPRT and received chemotherapy was 27 months compared with 14 months if they did not have surgery (p<0.0001). Median OS of patients who received all active agents and had SPRT was 39 months (95% CI: 25.1-52.9). On multivariate analysis SRPT, hazard ratio (HR) for mortality of 0.44 (95% CI: 0.35-0.56), use of chemotherapy, HR 0.33 (95% CI: 0.26-0.43), metastasectomy, HR 0.43 (95% CI: 0.31-0.58), second line therapy, HR 0.50 (95% CI: 0.35-0.70), and third line therapy, HR 0.58 (95% CI: 0.41-0.83) were independently correlated with superior survival. Elevated alkaline phosphatase, (HR 1.50 (95% CI: 1.20-1.78), grade 3 tumor, HR 1.33 (95% CI: 1.10-1.62), leukocytosis, HR 1.32 (95% CI: 1.05-1.66), stage IVb disease, HR 1.31 (95% CI: 1.10-1.56), and ECOG PS>1, HR 1.30 (95% CI: 1.04-1.57) were correlated with inferior survival. Conclusions: Our study supports SRPT in patients with stage IV CRC who are treated with modern combination of chemotherapy and biologics.

Immune response and its correlation with the disease activity in patients with advanced colorectal cancer (aCRC): Results from a prospective observational study

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Background: Currently limited biomarkers are available to monitor disease status in cancer patients. Although host factors are critical in regulating cancer, the role of immune responses in aCRC is less clear. A predominant T helper 1 (Th1) response may be more effective to contain cancer than one with a substantial Th2 component. The Th1/Th2 phenotype can be inferred from relative prevalence of IgG isotypes among anti-cancer antibodies and may provide an innovative way to assess disease activity. The study aims to develop an ELISA assay to monitor IgG1:IgG2 and its utility in predicting disease status in aCRC. Methods: A validated ELISA assay (Bertech Pharma) utilizing CRC cell lines was developed to measure IgG1 (Th2) and IgG2 (Th1) levels. A sample size of 44 (24 CRC and 20 healthy control [HC]) was estimated to achieve 80% power and α error of 0.05 assuming that the assay correctly detect CRC specific antibody in > 80% cases. The IgG1:IgG2 was compared between/within groups with HC and aCRC. Results: Samples were collected from 62/66 individuals recruited at 2:1 over 1 yr. 43 CRC patients had median age of 65 yrs (39-86) and M:F 2.3:1. 25 had >1 metastatic site, 31 underwent primary tumor resection and 37 received chemotherapy. Using standard criteria, 14/43 (33%) CRC patients had elevated 1gG1 titer compared with 2/19 (10%) HCs (p = 0.06). Mean IgG1 of CRC group was 0.18±0.05 compared with 0.15±0.01 in HC (p = 0.01). Conversely, mean IgG2 level of CRC group was 0.26±0.11 compared with 0.38±0.15 in HC (p = 0.003). Mean IgG2:IgG1 of CRC group was 1.5±0.35 compared with 2.5±0.97 in HC (p < 0.001). Among 43 CRC patients, 7/12 (58%) with disease progression (DP) had elevated IgG1 compared 7/31 (23%) with stable disease (p = 0.03). Strikingly, 9/12 (75%) patients who died had elevated IgG1 compared with 5/31 (16%) who were alive during the follow up, p = 0.001. Logistic regression revealed positive association among elevated IgG1 and DP, HR:4.8 (95% CI:1.2-19.9) and mortality, HR:15 (95% CI:3.1-78.8). Conclusions: Our results revealed that patients with aCRC have abnormal IgG1:IgG2 compared with HC and elevated IgG1 (a predominant Th2 response) levels in aCRC correlate with DP and mortality.

Survival impact of surgical resection of primary tumor in patients with stage IV colorectal cancer: results from a large population-based cohort study

BACKGROUND

Currently, there is very low-quality evidence available regarding benefit of surgical resection of the primary tumor (SRPT), in patients with stage IV colorectal cancer (CRC). In the absence of randomization, the reported benefit may reflect selection of younger and healthier patients with good performance status. A large population-based cohort study was undertaken to determine the survival benefit of SRPT in advanced CRC by eliminating various biases reported in the literature.

METHODS

A retrospective cohort study involving patients with stage IV CRC, diagnosed between 1992 and 2005, in the province of Saskatchewan, Canada. Survival was estimated by using the Kaplan-Meier method. Survival distribution was compared by log-rank test. Cox proportional multivariate regression analysis was performed to determine survival benefit of SRPT by controlling other prognostic variables.

RESULTS

A total of 1378 eligible patients were identified. Their median age was 70 years (range, 22-98 years) and male:female ratio was 1.3:1; 944 (68.5%) of them underwent SRPT. Among 1378 patients, 42.3% received chemotherapy and 19.1% received second-generation therapy. Patients who underwent SRPT and received chemotherapy had median overall survival of 18.3 months (95% confidence interval [CI] = 16.6-20 months) compared with 8.4 months (95% CI = 7.1-9.7 months) if they were treated with chemotherapy alone (P < .0001). Cox proportional analysis revealed that use of chemotherapy (hazard ratio [HR] = 0.47, 95% CI = 0.41-0.54), SRPT (HR = 0.49, 95% CI = 0.41-0.58), second-line chemotherapy (HR = 0.47, 95% CI = 0.45-0.64), and metastasectomy (HR = 0.54, 95% CI = 0.45-0.64) were correlated with superior survival.

CONCLUSIONS

SRPT improves survival in patients with stage IV CRC, independent of other prognostic variables including age, performance status, comorbid illness and chemotherapy.

Should noncurative resection of the primary tumour be performed in patients with stage iv colorectal cancer? A systematic review and meta-analysis

PURPOSE

Surgical resection of the primary tumour in patients with advanced colorectal cancer (crc) remains controversial. This review compares survival in patients with advanced crc who underwent surgical resection of the primary tumour with that in patients not undergoing resection, and determines rates of post-operative mortality and nonfatal complications, the primary tumour complication rate, the non-resection surgical procedures rate, and quality of life (qol).

METHODS

Reports in the central, medline, and embase databases were searched for relevant studies, which were selected using pre-specified eligibility criteria. The search was also restricted to publication dates from 1980 onward, the English language, and studies involving human subjects. Screening, evaluation of relevant articles, and data abstraction were performed in duplicate, and agreement between the abstractors was assessed. Articles that met the inclusion criteria were assessed for quality using the Newcastle-Ottawa Scale. Data were collected and synthesized per protocol.

RESULTS

From among the 3379 reports located, fifteen retrospective observational studies were selected. Of the 12,416 patients in the selected studies, 8620 (69%) underwent surgery. Median survival was 15.2 months (range: 10-30.7 months) in the resection group and 11.4 months (range: 3-22 months) in the non-resection group. Hazard ratio for survival was 0.69 [95% confidence interval (ci): 0.61 to 0.79] favouring surgical resection. Mean rates of postoperative mortality and nonfatal complications were 4.9% (95% ci: 0% to 9.7%) and 25.9% (95%ci: 20.1% to 31.6%) respectively. The mean primary tumour complication rate was 29.7% (95% ci: 18.5% to 41.0%), and the non-resection surgical procedures rate in the non-resection group was 27.6% (95 ci: 15.4% to 39.9%). No study provided qol data.

CONCLUSIONS

Although this review supports primary tumour resection in advanced crc, the results have significant biases. Randomized trials are warranted to confirm the findings.

Survival benefit and complications of primary tumor resection (PTR) in patients with stage IV colorectal cancer (CRC) in the era of modern chemotherapy: A systematic review and meta-analysis

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Background: Although there is evidences that PTR in advanced CRC may improve outcome, most studies were conducted during the period of monotherapy with 5-fluorouracil. Limited data is available regarding potential benefits and risk of PTR in patients with stage IV CRC treated with modern chemotherapy (MC). A recent phase II study suggested that outcomes are not compromised by leaving the primary colon tumor intact in such patients (JCO.2012;30:3223). Purpose:To compare survival of patients with advanced CRC who underwent PTR with patients without resection in the era of MC. The review also aims to determine post-operative mortality and non-fatal complications rates, primary tumor complications rate (PTCR), non-resection surgical procedures rate (NSPR) and quality of life (QOL). Methods: A literature search was conducted by using CENTRAL (2012), Medline (1946-2012), and EMBASE (1947-2012). Studies involving patients with stage IV CRC who underwent PTR were selected with restriction to publication dates from 2000, English language and human studies. Screening, evaluation of relevant articles and data abstraction was done in duplication and agreement was assessed. Articles that met the inclusion criteria were assessed for quality by using Ottawa-Newcastle score. Data was collected and synthesized as per protocol. Results: Of total of 3,379 reports, 10 retrospective studies were selected with patients population of 2,655. Among 2,655 patients, 1616 (61%) underwent PTR with a median overall survival of 18.7 months (range: 11-30.7) compared with 12.9 months (range: 5.8-22) in the control. The HR for survival was in 0.68 (95% CI: 0.56-0.83) favoring the PTR. Mean 30 days post-operative mortality rate in the PTR group was 3.9% (95% CI: 0-11). Mean PTCR and NSPR in the control group were 27.4% (95% CI: 16.4-38.5) and 27% (95% CI: 12.5-41.6) respectively. No study provided QOL. Conclusions: The retrospective data favors PTR in advanced CRC in the era of modern chemotherapy. Future prospective randomized trials are warranted to confirm the findings.

Survival impact of surgical resection of primary tumor (SRPT) in metastatic colorectal cancer (mCRC): A population-based cohort study

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Background: Currently there is very low quality evidence available regarding survival benefit of SRPT in patients with mCRC. In the absence of randomization the reported benefit may reflect selection of younger and healthier patients with good performance status (PS). We have undertaken a retrospective cohort study to determine the survival benefit of SRPT in mCRC. Methods: A cohort of 1,378 patients with mCRC diagnosed between 1992-2005 in the province of Saskatchewan was evaluated. Kaplan-Meier curves were used to determine survival. Log-Rank test was done to compare survival between the two groups. Cox regression model was used to adjust survival for important prognostic variables. Results: Median age was 70 yrs (22-98) and M:F was 57:43. 27% had ECOG PS of >1 and 62% had a comorbid illness. 944 (69%) patients underwent SRPT. Among 1,378 patients, 40% were operated for tumor related symptoms (33% obstruction, 6% perforation, and 4% heavy bleeding, mutually nonexclusive). Median follow up time for whole cohort was 7.1 months (inter-quartile range 2.5-17.5). 42.3% received chemotherapy and 19.1% received 2nd generation therapy. Median survival of patients who received chemotherapy was 15.9 months. Patients who underwent SRPT had median overall survival of 18.3 months vs. 8.4 months if they did not have surgery (p<0.0001).On multivariate analysis 5FU-based chemotherapy (HR 0.53; 95%CI: 0.45-0.61), metastesectomy (HR 0.54; 95%CI: 0.45-0.64), SRPT (HR 0.55; 95%CI: 0.48-0.62), and 2nd generation chemotherapy (HR 0.65; 95%CI: 0.54-0.77) were correlated with a better survival whereas, elevated CEA level (1.56; 95%CI: 1.30-1.90), leukocytosis (HR 1.54; 95%CI: 1.33-1.80), ECOG PS >1 (HR 1.48; 95%CI: 1.30-1.69), low albumin (HR 1.44; 95%CI: 1.26-1.64), age ≥ 65 yrs (HR 1.21; 95%CI: 1.10-1.38), anemia (HR 1.16; 95%CI: 1.03-1.31), and symptomatic disease (HR 1.12; 95%CI: 1.0-1.26) were correlated with poor survival. Comorbid illness, smoking, and gender did not correlate with survival. Conclusions: This is the first large cohort study that reveals that SRPT in patients with mCRC improves survival independent of chemotherapy, age, functional status and comorbid illness.

Abstract P3-14-15: Lapatinib Plus Capecitabine in Trastuzumab Pre-Treated HER2- Positive Metastatic Breast Cancer: The Canadian Lapatinib Expanded Access Program Experience

BACKGROUND:

The global lapatinib expanded access programme (LEAP) provided access to lapatinib (L) combined with capecitabine (C) for women with HER2- positive metastatic breast cancer (MBC) who were previously treated with an anthracycline (A), taxane (T) and trastuzumab (TRAS) in 45 countries. The eligibility criteria and the dose of given drugs resembled that used in the phase III clinical trial EGF 100151, with the exception that patients (pts)previously exposed to C and pts with an ECOG performance status of 2 could be included as well. L is a dual tyrosine kinase inhibitor of EGFR and HER2. L plus C is an effective treatment option in T-refractory HER2-positive MBC. 148 Canadian pts were enrolled. METHODS:

LEAP enrolled patients with ErbB2-positive, locally advanced and MBC showing progressive disease following prior therapies with A, T, TRAS-containing regimens. Pts received L (1,250 mg/day) and C (2,000 mg/m2/day, days 1-14, every 21 days). We analyzed 148 Canadian LEAP pts recruited from seven centres for demographics, duration of therapy, L compliance, left ventricular function, progression-free survival (PFS), and overall survival (OS). RESULTS:

Data cut off for these analyses was Jan 10, 2010. [Data were not available for all 148 pts. The median age was 52 y (range 29-80 y) for 147 pts (145 women, 2 men). Ninety-five pts (64.6%) had no prior C and 52 (35.4%) had prior C (n=147). Study medication was discontinued for 142 pts (96.6%): 110 (74.8%) for progressive disease; 17 (11.6%) for adverse events; 8 (5.4%) for patient preference; and 3 (2%) were transitioned to the commercial supply of L. The median duration of therapy was 18.95 wk, ranging 0.1 to 96 wk (n=137). L compliance data showed that 73.7% of pts received ≥80% of the L dose (n=122). Median baseline left ventricular function (LVF) was 60%, ranging 50% to 81% (n=142). The median LVF at study end was 61%, ranging 37% to 83% (n = = 96). There was an amendment in June 2008 to end the collection of disease progression and/or death dates. Median PFS and OS were 22.1 wk (95% CI: 18.9-26.7), and 48 wk (95% CI: 42.3-…), respectively (n=71). CONCLUSIONS:

L combined with C is an effective option for women with refractory HER2-positive MBC. The results seen in the Canadian subset enrolled in LEAP were similar to the results of EGF 100151 and the Global LEAP in the efficacy and safety data.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-14-15.

Early discontinuation but not the timing of adjuvant therapy affects survival of patients with high-risk colorectal cancer: a population-based study

BACKGROUND

Adjuvant therapy results in significant improvement in survival of patients with high-risk colorectal cancer. Little is known about the significance of timing and early discontinuation of adjuvant treatment in such patients. Our study aims to determine the prognostic impact of timing and completion of adjuvant therapy in patients with high-risk colorectal cancer.

METHODS

Medical records of patients with stage III colon and stage II/III rectal cancer diagnosed between 1993 and 2000 in the province of Saskatchewan were reviewed. Cox proportional hazards models were used to analyze the impact of timing and completion of adjuvant therapy on survival.

RESULTS

Six hundred sixty-three eligible patients with a median age of 66 years were identified. Sixty-five percent patients received adjuvant <56 days after surgery and 79% patients completed planned treatment. Median follow-up was 54.6 months. Five-year disease-free survival and overall survival of patients who received adjuvant therapy <56 days after surgery was 54.6% and 59.5%, respectively, compared with 51.9% and 57.1%, respectively, of patients who received therapy ≥56 days after surgery (P = NS). The five-year disease disease-free survival and overall survival of patients who completed planned treatment was 56.7% and 62.3%, respectively, compared with 42.1% and 45%, respectively, of patients who required early treatment discontinuation (P < .0001). On multivariate analysis, age ≥65 years, T4 tumor, grade 3 cancer, node-positive disease, rectal tumor, and early treatment discontinuation were identified as poor prognostic factors.

CONCLUSIONS

Although time to adjuvant therapy following surgical resection did not impact the outcomes, failure to complete planned therapy was associated with adverse prognosis.

Physical Health Co-Morbidity in Patients with Acquired Brain Injury (ABI), Receiving in-Patient Neurobehavioural Rehabilitation

Background:

Patients with Acquired Brain Injury (ABI) present with a range of physical health problems. Co-morbid physical conditions can complicate these patients’ rehabilitation and also may lead to secondary disabilities. The medical literature provides limited information on the prevalence of physical health issues in patients with ABI.

Methods:

We surveyed health records of 64 patients receiving multi-disciplinary rehabilitation at a tertiary Brain Injury Rehabilitation service. The data was collected in an anonymized fashion and analyzed using SPSS version 16.

Results:

We analysed data from 64 patients (51 Male, 13 Female). The age range was 21-61 years (Mean 39, S.D. 10.6). Epilepsy was the commonest co-existing physical health condition (47%) amongst these patients. Chronic constipation (20%), peptic ulcer disease (14%), Insulin dependent diabetes mellitus (11%), Asthma/COPD (9%), recurrent urinary tract infection (8%) and hypothyroidism (8%) were the co-existing conditions for which the patients needed treatment. Also dysphasia (38%), dysartheria (34%), dysphagia (28%) and mobility difficulties (37%) were common in this patient group.

Conclusions:

These findings have implications for continuing medical education needs for psychiatrists and other health care professionals working in this field. The findings also highlight the need for improved communication and working relationship between psychiatric and general hospital based specialities in order to implement holistic delivery of care for patients with ABI.

Impact of timing of initiation of adjuvant chemotherapy on survival after resection of colorectal cancer

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Background: Based on the results of intergroup trials, adjuvant chemotherapy has become the standard of care for patients with Duke stage C colon and Duke stages B and C rectal cancer. Although initiation of adjuvant chemotherapy soon after recovery from surgery is desirable, only few studies have examined whether a delay in starting adjuvant chemotherapy affect clinical outcomes. Our objective in this study is to determine the impact of timing of adjuvant chemotherapy on survival after resection of Duke stage C colon and Duke stages B and C rectal cancer. Methods: Study involves use of the information available from patients chart review in the province of Saskatchewan, Canada. Patients 18 years of age and older (median age 66 years), diagnosed with Duke Stage C colon and Duke stages B and C rectal cancer between 1993 and 2000 were included. Median followup was 54.8 months. All patients with rectal cancer received radiation treatment as per institution policy. Cox proportional hazards models were used to analyze the impact of timing of adjuvant chemotherapy on survival. Results: Among 701 patients eligible for study, 453 (64.6%) patients received adjuvant chemotherapy within 56 days of surgery (group I) and 248 patients (35.3 %) received adjuvant chemotherapy after 56 days of surgery (group II). Median time interval between surgery and the initiation of adjuvant chemotherapy in group I, and II were 41 days and 70 days respectively. Five year DFS for group I was 39% as compared to 37% for group II (HR 0.94, CI 0.76–1.16, p = 0.58). Median OS for group I was 97.5 months as compared to 68.9 months (HR 1.08, CI 0.85–1.37, p= 0.54). Age, histology and number of lymph nodes analyzed, were identified as independent prognostic factors in multivariate analysis. Conclusions: In this study, patients with Duke stage C colon and Duke stages B and C rectal cancer who received adjuvant chemotherapy within 56 days of resection has similar outcomes as compared to patients who received adjuvant chemotherapy after 56 days of resection.

[Table: see text]

Prognostic importance of primary tumor resection in patients with advanced colorectal cancer (CRC): A Canadian province’s experience

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Background: Surgical resection (SR) of primary tumor in patients with newly diagnosed advanced CRC remains controversial. Limited data is available regarding potential benefit of resection in these patients. We performed a population-based study to determine the prognostic value of SR of primary tumor in patients with metastatic CRC. Methods: Medical records of patients with metastatic CRC diagnosed between 1991–2000 in the province of Saskatchewan were reviewed. Patients with unresectable T4M0 disease were excluded. A multivariate analysis was performed using Cox regression model and various clinicopathologic variables were tested for their prognostic significance. Kaplan-Meier curves were used to determine survival. A preliminary analysis of data of 212 eligible patients diagnosed between 1998–2000 is presented here. Results: Patients median age was 71 yrs (33–94) and M:F was 1:0.77. One hundrad thirty one (62%) patients underwent SR for the primary tumor. Among 131 patients, 76 (58%) were operated for tumor related symptoms (36% obstruction, 14% perforation, and 9% bleeding). Six percent patients died of postoperative complications. Of 212 patients, 36% received 5FU-based chemotherapy (46% patients with SR) and 17% received a second line therapy. Median overall survival (OS) of all patients was 6.7 months. Patients who underwent SR of primary tumor had a significantly better median OS of 11 months compared with 3 months in patients who did not have surgery (HR 0.47; 95% CI 0.29–0.76). Patients who underwent SR and had received chemotherapy had a median OS of 14.8 months compared with median OS of 6 months if they did not receive chemotherapy (HR, 0.29; 95% CI 0.15–0.55). In addition to 5FU-based chemotherapy and SR of primary tumor; metastectomy, age >65 yrs, elevated alkaline phosphatase level and thrombocytosis were other important variables that were correlated with survival in patients with advanced CRC. Conclusions: SR of primary tumor has been associated with significant improvement in survival independent of systemic chemotherapy in patients with advanced CRC. Further analysis of data in patients diagnosed between 1991–2000 is planned to confirm these findings in a larger group of patients.

No significant financial relationships to disclose.