Metastatic spread pattern after curative colorectal cancer surgery. A retrospective, longitudinal analysis.

OBJECTIVE: The most common sites of colorectal cancer (CRC) recurrence are the local tissues, liver or lungs. The objective was to identify risk factors associated with the primary CRC tumor and cancer recurrence in these anatomical sites. METHODS: Retrospective, longitudinal analyses of data on CRC survivors. Multivariable Cox regression analysis was performed to examine the association between possible cofounders with recurrence to various anatomical sites. RESULTS: Data for 10,398CRC survivors (tumor location right colon=3870, left colon=2898, high rectum=2569, low rectum=1061) were analyzed; follow up time was up to five years. Mean age at curative surgery was 71.5 (SD 11.8) years, 20.2% received radio-chemotherapy, stage T3 (64.4%) and N0 (65.1%) were most common. Overall 1632 (15.7%) had cancer recurrence (Isolated liver n=412, 3,8%; isolated lung n=252, 2,4%; isolated local n=223, 2.1%). Risk factors associated with recurrent CRC were identified, i.e. isolated liver metastases (male: Adjusted Hazard Ratio (AHR) 1,45; colon left: AHR 1,63; N2 disease: AHR 3,35; T2 disease: AHR 2,82), isolated lung metastases (colon left: AHR 1,53; rectum high: AHR 2,48; rectum low: AHR 2,65; N2 disease 3,76), and local recurrence (glands examined<12: AHR 1,51; CRM <3mm: AHR 1,60; rectum high: AHR 2,15; N2 disease: AHR 2,58) (all p values <0001). CONCLUSION: Our study finds that the site of the primary CRC tumor is associated with location of subsequent metastasis. Left sided colon cancers have increased risk of metastatic spread to the liver, whereas rectal cancers have increased risk of local recurrence and metastatic spread to the lungs. These results, in combination with other risk factors for CRC recurrence, should be taken into consideration when designing risk adapted post-treatment CRC surveillance programs.

Survival effect of implementing national treatment strategies for curatively resected colonic and rectal cancer.

BACKGROUND: The surgical management of rectal cancer has changed substantially over the past decade. There are limited data on the long-term outcome of implementing systematic management strategies. METHODS: Survival of a national cohort of patients treated surgically for colonic and rectal cancer over a 10-year interval was analysed. All 31 158 patients in Norway diagnosed with adenocarcinoma of the colon and rectum between 1994 and 2003 were identified from the Cancer Registry of Norway and the Norwegian Rectal Cancer Registry. Changes in 5-year relative survival were compared by age, stage and tumour location during the early and late years. RESULTS: The study population included 19 053 patients who had a curative resection. The relative 5-year survival rate significantly improved for both colonic cancer (73·8 versus 78·0 per cent; P < 0·001) and rectal cancer (72·1 versus 79·6 per cent; P < 0·001). The 5-year relative survival was significantly better for rectal than colonic cancer during the late period (P = 0·030). Improved 5-year relative survival was related to better outcomes in patients with positive lymph nodes (67·2 and 62·1 per cent for rectal and colonic cancer respectively; each P < 0·001 versus early period), but not for the subgroup aged over 75 years with lymph node-positive colonic cancer. CONCLUSION: In this national cohort, survival after curative surgery for colorectal cancer increased significantly after implementation of national management strategies. Improvements were most evident for rectal cancer and in lymph node-positive disease; they were less substantial for colonic cancer and elderly patients (over 75 years). Strategic treatment changes may be warranted for the latter group.

Locally recurrent rectal cancer in Norway.

BACKGROUND: The purpose of this study was to describe management and outcome in patients with locally recurrent rectal cancer based on data from the Norwegian Colorectal Cancer Registry. METHODS: This was a prospective national cohort study of 577 patients with local recurrence after major resection (R0/R1) for rectal cancer between November 1993 and December 2001 (initial cohort of 4504 patients). RESULTS: Of the 577 patients, 185 (32.1 per cent) had curative resections (R0/R1), 203 (35.2 per cent) had palliative radiotherapy with or without palliative surgery and chemotherapy, and 189 (32.8 per cent) received no treatment at all or only palliative surgery or chemotherapy. The overall 5-year survival rate was 14.9 per cent. Ninety-seven patients had an R0 resection, and 88 had an R1 resection, with 5-year overall survival of 55 and 20 per cent respectively. This outcome reflected surgical treatment in 33 different hospitals. Some 274 patients (47.5 per cent) had metastases. The 5-year survival rate after R0 resection was 62 per cent in patients without metastases. CONCLUSION: Obtaining an R0 resection is the most important prognostic factor in treating recurrent rectal cancer.