Staging error does not explain the relationship between the number of lymph nodes in a colon cancer specimen and survival
ABSTRACT Survival in colon cancer is greater in those patients who have more lymph nodes identified at resection and may be due to stage migration, confounding by treatment, social, or clinical characteristics. Identifying factor(s) responsible for the effect may represent an opportunity to improve quality of care for patients with colon cancer by increasing node counts in specimens.
Cox proportional hazards models were created to analyze survival of 11,399 patients with stage I-III colon cancer from the Surveillance, Epidemiology and End Results (SEER)-Medicare database. The primary predictor variable was the number of lymph nodes identified. The models allowed adjustment for patient factors, use of chemotherapy, surgical specialty, and the average number of nodes identified by surgeon and hospital pathologist.
The number of nodes identified was related to survival. Compared to those with less than 7 nodes, patients with 7 to 11 nodes had a 13% lesser risk of death (hazard ratio [HR], 0.87; 95% confidence interval [CI], 0.76-0.99; P = .037). Patients with more than 12 nodes had a 17% lesser risk (HR, 0.83; 95% CI, 0.73-0.95; P = .005). Adjusting for selected patient demographic characteristics, receipt of chemotherapy, surgical specialty, and the average number of nodes identified per specimen by the surgeon or hospital did not significantly alter the relationship between number of nodes and survival.
These findings argue against understaging or confounding as the explanation for the inferior survival observed in patients with fewer nodes identified. National initiatives to increase the number of nodes identified in colon cancer specimens may not improve substantially the cancer-specific outcomes.
- SourceAvailable from: Marianne Tijssen
[Show abstract] [Hide abstract]
- "Several studies strongly confirm the association between high LN yield and improved survival in colorectal cancer patients, both in stage II and III disease.10,15,18,25,30,31 "
ABSTRACT: Lymph node (LN) yield in colon cancer resection specimens is an important indicator of treatment quality and has especially in early-stage patients therapeutic implications. However, underlying disease mechanisms, such as microsatellite instability (MSI), may also influence LN yield, as MSI tumors are known to exhibit more prominent lymphocytic antitumor reactions. The aim of the present study was to investigate the association of LN yield, MSI status, and recurrence rate in colon cancer. Clinicopathological data and tumor samples were collected from 332 stage II and III colon cancer patients. DNA was isolated and PCR-based MSI analysis performed. LN yield was defined as "high" when 10 or more LNs were retrieved and "low" in case of fewer than 10 LNs. Tumors with high LN yield were significantly associated with the MSI phenotype (high LN yield: 26.3% MSI tumors vs low LN yield: 15.1% MSI tumors; P=.01), mainly in stage III disease. Stage II patients with high LN yield had a lower recurrence rate compared with those with low LN yield. Patients with MSI tumors tended to develop fewer recurrences compared with those with MSS tumors, mainly in stage II disease. In the present study, high LN yield was associated with MSI tumors, mainly in stage III patients. Besides adequate surgery and pathology, high LN yield is possibly a feature caused by biologic behavior of MSI tumors.Annals of Surgical Oncology 10/2011; 19(4):1222-30. DOI:10.1245/s10434-011-2091-7 · 3.93 Impact Factor
Conference Paper: Current Mode Column Driver for FEDVacuum Microelectronics Conference, 1997. Technical Digest., 1997 10th International; 09/1997
- Archives of surgery (Chicago, Ill.: 1960) 08/2010; 145(8):797-8; author reply 798-9. DOI:10.1001/archsurg.2010.135 · 4.93 Impact Factor