Is total mesorectal excision always necessary for T1-T2 lower rectal cancer?
ABSTRACT The goal of this multicenter study was to clarify the determinants of local excision for patients with T1-T2 lower rectal cancer.
Data from 567 consecutive patients who underwent radical resection for T1-T2 lower rectal cancer at 12 institutions between 1991 and 1998 were reviewed. Rates of lymph node metastasis were investigated using a tree analysis, which was hierarchized using independent risk factors for nodal involvement.
The independent risk factors for lymph node metastasis were female gender, depth of tumor invasion, histology other than well-differentiated adenocarcinoma, and lymphatic invasion. According to the first three parameters that can be obtained preoperatively, only 0.99% of the patients without risk factors had lymph node metastasis. On the other hand, even if the lower rectal cancer was at stage T1, women with histological types other than well-differentiated adenocarcinoma had an approximately 30% probability of having lymph node metastasis. Lymphatic invasion was most useful to predict nodal involvement among patients with T2 lower rectal cancer. The rates of lymph node metastasis in T2 patients with and without lymphatic invasion were 32.9% and 9.1%, respectively.
Gender is one of the most important predictors for lymph node metastasis in patients with early distal rectal cancer. Three parameters, including depth of tumor invasion, histology, and gender, are useful determinants for local excision. Additional studies are required to establish the minimum optimal treatment for T2 lower rectal cancer.
- [Show abstract] [Hide abstract]
ABSTRACT: AIM: To identify the predictors of distant metastasis in pathologically T1 (pT1) colorectal cancer (CRC) after radical resection.METHODS: Variables including age, gender, preoperative carcinoembryonic antibody (CEA) level, tumor location, tumor size, lymph node status, and histological grade were recorded. Patients with and without metastasis were compared with regard to age, gender, CEA level and pathologic tumor characteristics using the independent t test or χ(2) test, as appropriate. Risk factors were determined by logistic regression analysis.RESULTS: Metastasis occurred in 6 (3.8%) of the 159 patients during a median follow-up of 67.0 (46.5%) mo. The rates of distant metastasis in patients with pT1 cancer of the colon and rectum were 6.7% and 2.9%, respectively (P < 0.001). The rates of distant metastasis between male and female patients with T1 CRC were 6.25% and 1.27%, respectively (P < 0.001). The most frequent site of distant metastasis was the liver. Age (P = 0.522), gender (P = 0.980), tumor location (P = 0.330), tumor size (P = 0.786), histological grade (P = 0.509), and high serum CEA level (P = 0.262) were not prognostic factors for lymph node metastasis. Univariate analysis revealed that age (P = 0.231), gender (P = 0.137), tumor location (P = 0.386), and tumor size (P = 0.514) were not risk factors for distant metastasis after radical resection for T1 colorectal cancer. Postoperative metastasis was only significantly correlated with high preoperative serum CEA level (P = 0.001). Using multivariate logistic regression analysis, high preoperative serum CEA level (P = 0.004; odds ratio 15.341; 95%CI 2.371-99.275) was an independent predictor for postoperative distant metastasis.CONCLUSION: The preoperative increased serum CEA level is a predictive risk factor for distant metastasis in CRC patients after radical resection. Adjuvant chemotherapy may be necessary in such patients, even if they have pT1 colorectal cancer.World Journal of Gastroenterology 01/2013; 19(3):389-393. · 2.43 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: The accurate preoperative diagnosis of depth of tumor invasion and nodal status in distal rectal cancer is important because neoadjuvant chemotherapy or lateral pelvic lymph node dissection is indicated for patients with T3-T4 tumor or nodal involvement. This study aimed to determine the optimal cutoff value for predicting lymph node metastasis in patients with distal rectal cancer using multidetector row computed tomography (MDCT).Annals of Surgical Oncology 08/2014; · 3.94 Impact Factor
Conference Paper: A 2.2 V 300 /spl mu/A RDS pager baseband decoder[Show abstract] [Hide abstract]
ABSTRACT: Compared with more advanced wireless telecommunication systems such as GSM, the pager offers the advantages of a lower cost, a smaller size and a longer battery autonomy. Furthermore, the RDS pager system allows reuse of the existing network of FM radio broadcasting stations, reducing the cost of introduction of the pager network and allowing immediately a large geographical coverage. The realization ofthe RDS baseband decoder described is a first step of an attempt to increase the pager battery autonomy from a few weeks to more than a half year.Solid-State Circuits Conference, 1997. Digest of Technical Papers. 43rd ISSCC., 1997 IEEE International; 01/1997