Prospective multicenter registration study of colorectal cancer: significant variations in radicality and oncosurgical quality-Swiss Group for Clinical Cancer Research Protocol SAKK 40/00

Is surgical quality more important than radicality? Long-term outcomes of stage I-III colon cancer (SAKK 40/00)

BACKGROUND

To prospectively determine the influence of variations of surgical radicality and surgical quality on long-term outcome in patients with stage I-III colon cancer.

METHODS

From a prospective multicenter cohort study including 1040 patients undergoing surgery for colorectal cancer from 09/2001 to 06/2005 in nine Swiss and one German hospital, 423 patients with stage I-III colon cancer were selected and analyzed. Surgeons and pathologists filled in standardized forms prospectively assessing items of oncosurgical radicality and quality. Patients had standardized follow-up according to national guidelines.

RESULTS

Follow-up was median 6.2 years (range 0.3-10.4) showing a 5-year disease-free survival/overall survival of 83 %/87 % in stage I (n = 85), 69 %/77 % in stage II (n = 187), and 53 %/61 % in stage III (n = 151) colon cancer. Despite remarkable variations of oncosurgical radicality and quality, the multivariate model revealed that mainly quality items correlated significantly with disease-free survival (surgical tumor lesion HR 2.12, p = 0.036, perioperative blood transfusion HR 1.67, p = 0.018, emergency resection HR 1.74, p = 0.035) and overall survival (early venous ligation HR 0.66, p = 0.023, surgical tumor lesion HR 2.28, p = 0.027, perioperative blood transfusion HR1.79, p = 0.010, emergency resection HR 1.88, p = 0.026), while radicality parameters (length of specimen, distance of the tumor to nearest bowel resection site, number of lymph nodes, height of resected mesocolon and of central vascular dissection) did not.

CONCLUSION

Surgical quality seems to have a stronger impact on oncologic long-term outcome in stage I - III colon cancer than surgical radicality.

A systematic review and meta-analysis comparing surgical and oncological outcomes of upper rectal, rectosigmoid and sigmoid tumours

AIM

Management paradigms for tumours from the sigmoid colon to the lower rectum vary significantly. The upper rectum (UR) represents the transition point both anatomically and in treatment protocols. Above the UR is clearly defined and managed as colon cancer and below is managed as rectal cancer. This study compares outcomes between sigmoid, rectosigmoid and UR tumours to establish if differences exist in operative and oncological outcomes.

METHODS

Electronic databases were searched for published studies with comparative data on peri-operative and oncological outcome for upper rectal and sigmoid/rectosigmoid (SRS) tumours treated without neoadjuvant radiation. The search adhered to PRISMA guidelines (Preferred Reporting Items in Systematic Reviews and Meta-analyses) guidelines. Data was combined using random-effects models.

RESULTS

Seven comparative series examined outcomes in 4355 patients. There was no difference in ASA grade (OR, 1.28; 95% CI, 0.99-1.67; P = 0.06), T3/T4 tumours (OR, 1.24; 95% CI, 0.95-1.63; P = 0.12), or lymph node positivity (OR, 0.97; 95% CI, 0.70-1.36; P = 0.87). UR cancers had higher rates of operative morbidity (OR, 0.72; 95% CI, 0.55-0.93; P = 0.01) and anastomotic leak (OR, 0.47; 95% CI, 0.31-0.71; P = 0.0004). There was no difference in local recurrence (OR, 0.63; 95% CI, 0.37-1.08; P = 0.10). SRS tumours had lower rates of distant recurrence (OR, 0.83; 95% CI, 0.68-1.0; P = 0.05). Rectosigmoid operative and cancer outcomes were closer to UR than sigmoid.

CONCLUSIONS

Based on existing data, UR and rectosigmoid tumours have higher morbidity, leak rates and distant recurrence than more proximal tumours.

Evaluation of the prognostic relevance of the recommended minimum number of lymph nodes in colorectal cancer-a propensity score analysis

PURPOSE

Nodal status in colorectal cancer (CRC) is an important prognostic factor, and adequate lymph node (LN) staging is crucial. Whether the number of resected and analysed LN has a direct impact on overall survival (OS), cancer-specific survival (CSS) and disease-free survival (DFS) is much discussed. Guidelines request a minimum number of 12 LN to be analysed. Whether that threshold marks a prognostic relevant cut-off remains unknown.

METHODS

Patients operated for stage I-III CRC were identified from a prospectively maintained database. The impact of the number of analysed LN on OS, CSS and DFS was assessed using Cox regression and propensity score analysis.

RESULTS

Of the 687 patients, 81.8% had ≥ 12 LN resected and analysed. Median LN yield was 17.0 (IQR 13.0-23.0). Resection and analysis of ≥ 12 LN was associated with improved OS (HR = 0.73, 95% CI: 0.56-0.95, p = 0.033), CSS (HR 0.52, 95% CI: 0.31-0.85, p = 0.030) and DFS (HR = 0.73, 95% CI: 0.57-0.95, p = 0.030) in multivariate Cox analysis. After adjusting for biasing factors with propensity score matching, resection of ≥ 12 LN was significantly associated with improved OS (HR = 0.59; 95% CI: 0.43-0.81; p = 0.002), CSS (HR = 0.34; 95% CI: 0.20-0.60; p < 0.001) and DFS (HR = 0.55; 95% CI: 0.41-0.74; p < 0.001) compared to patients with < 12 LN.

CONCLUSION

Eliminating biasing factors by a propensity score matching analysis underlines the prognostic importance of the number of analysed LN. The set threshold marks the minimum number of required LN but nevertheless represents a cut-off regarding outcome in stage I-III CRC. This analysis therefore highlights the significance and importance of adherence to surgical oncological standards.

Value of MRI morphologic features with pT1-2 rectal cancer in determining lymph node metastasis

BACKGROUND AND OBJECTIVES

To investigate the different features between metastatic lymph node and nonmetastatic lymph node on magnetic resonance imaging (MRI) and the relationship between the rectal lesion and lymph node metastasis (LNM).

METHODS

Eighty-two patients with retrospectively consecutive pT1-2 stage rectal cancer in 2016 were divided into lymph node metastasis (LNM+) and lymph node nonmetastasis (LNM-) group based on their histopathologic examinations. We evaluated the following features of lymph nodes: number, shape, signal heterogeneity, border, and diameter of the largest lymph node on T2-weight images. We also calculated tumor apparent diffusion coefficient ratio and tumor percent enhancement. Fisher's exact test was applied for inspecting lymph node numbers on MRI and logistic regression analysis in examining risk factors for LNM.

RESULTS

The MR-LN number was significantly different between the LNM+ and LNM- group (median: 4 vs 1, P = 0.001). Multivariate logistic regression analysis exhibited that the diameter of the largest lymph node and the tumor percent enhancement of the arterial phase were independent risk factors of LNM (P = 0.005 vs 0.021, respectively).

CONCLUSIONS

The largest lymph node's diameter and the tumor percent enhancement of arterial phase on MRI were helpful in determining LNM in pT1-2 rectal cancer.

Meta-analysis of histopathological outcomes of laparoscopic assisted rectal resection (LARR) vs open rectal resection (ORR) for carcinoma

BACKGROUND

We conducted a meta-analysis of the randomized evidence to determine the relative merits of histopathological outcomes of laparoscopic assisted (LARR) versus open rectal resection (ORR) for rectal cancer.

DATA SOURCES

A search of PubMed and other electronic databases comparing LARR and ORR between Jan 2000 and June 2016 was performed. Histopathological variables analyzed included; location of rectal tumors; complete and incomplete TME; positive and negative circumferential resection margins (+/-CRM); positive distal resected margins (+DRM); distance of tumor from DRM; number of lymph nodes harvested; resected specimen length; tumor size and perforated rectum.

RESULTS

Fourteen RCTs totaling 3843 patients (LARR = 2096, ORR = 1747) were analyzed. Comparable effects were noted for all these histopathological variables except for the variable perforated rectum which favored ORR.

CONCLUSIONS

LARR compares favorably to ORR for rectal cancer treatment. However, there is significantly higher risk of rectal perforation during LARR compared to ORR.

Improved perioperative care is associated with improved long-term survival in colorectal cancer

PURPOSE

To compare perioperative colorectal cancer care and survival in patient cohorts operated in 2005 and in 2010 in Lithuania.

METHODS

Comparative observational cohort study was performed. The study was conducted in the three Lithuanian cancer hospitals. Patients, who underwent curative surgery for colorectal cancer in 2005 and 2010, were included. Demographic characteristics, distribution of the tumors, preoperative diagnostics and staging, surgical treatment, the quality of pathological examination, morbidity, and mortality were analyzed. One- and 5-year overall survival data were compared between the groups.

RESULTS

Colorectal cancer diagnostics and treatment improved from 2005 to 2010 significantly. The disease was identified as stage III-IV for 45 vs. 48% of the patients; however, computed tomography staging scan was performed only for 5.9 vs. 17.8% in 2005 and 2010, respectively. Laparoscopic operations were performed 1.5 vs. 10.5% and abdominoperineal resections-42.7 vs. 31.7% in 2005 and 2010, respectively. The number of harvested lymph nodes was mentioned in 55.8 vs. 97.7% of the cases, whereas more than 12 lymph nodes were examined in 18 vs. 66.6% of cases after histological examination. The overall 5-year survival was 52.1 vs. 63.1% (p < 0.0001), while the 5-year survival of the patients with stage IV of disease was 4.2 vs. 17.8% in 2005 and 2010, respectively.

CONCLUSION

Preoperative investigation, surgical treatment, pathological examination, and postoperative course are associated with improved overall survival in colorectal cancer patients, undergoing curative surgery in the resource-limited settings.