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Biomedical subjects

Jen-Kou Lin

Publications and source records attributed to Jen-Kou Lin.

At least 37 records · Page 2Linked to original sources
PubMed2004

Sequence-dependent effect of a cyclooxygenase-2 inhibitor on topoisomerase I inhibitor and 5-fluorouracil-induced cytotoxicity of colon cancer cells.

Selective cyclooxygenase-2 (COX-2) inhibitors have been found to induce anti-proliferative and apoptotic activity in many cancer cells. However, interaction between COX-2 inhibitors and other chemotherapeutic agents remains to be determined. We investigated the interactive effects of a selective COX-2 inhibitor, etodolac, in combination with 5-fluorouracil (5-FU) or SN-38 (active metabolite of irinotecan) on colon cancer cell lines, HT29 and SW620, in simultaneous and sequential administration schedules. Isobologram analysis demonstrated that etodolac in combination with 5-FU or SN-38 according to a simultaneous schedule resulted in only an additive effect; however, synergism was achieved in a sequential schedule. Apoptosis induction in both cell lines was also significantly increased after sequential treatment with etodolac followed by either 5-FU or SN-38 compared to that after simultaneous treatment with etodolac and either 5-FU or SN-38. Our study suggests apoptosis-inducing synergism resulted from administration of etodolac and either 5-FU or SN-38 sequentially, but not simultaneously.

Apoptosis↗
PubMed2003

Anti-angiogenic effect of silymarin on colon cancer LoVo cell line.

OBJECTIVE: This study was designed to evaluate the anti-angiogenic effect of silymarin (SM) and its major pure component silibinin (SB), and also thalidomide (TH). MATERIALS AND METHODS: A modified in vitro system using a coculture of endothelial (EA.hy 926) and colon cancer (LoVo) cell lines was adopted in this study. RESULTS: In cytotoxicity assay, SM/SB/TH concentrations causing 20% (IC(20)) inhibition of cellular growth were 41.8 microg/ml/0.22 mM/0.088 mM for EA.hy 926 cells, and 16.1 microg/ml/0.12 mM/0.099 mM for LoVo cells, respectively. All 3 drugs showed concentration dependent inhibition of migration and differentiation assay. The IC(50) inhibiting chemotaxis migration of EA.hy 926 towards LoVo by SM/SB/TH was 1.15 microg/ml/0.66 microM/1.98 microM, respectively. In differentiation assay, SM/SB/TH inhibited in vitro capillary tube formation by 50% at 1.25 microg/ml/2.6 micro/6.3 microM, respectively. In an analysis of vascular endothelial growth factor secreted by LoVo cells, SM/SB/TH decreased 50% secretion at 6.52 microg/ml/6.6 microM/131.7 microM, respectively. CONCLUSION: SM/SB has a strong anti-angiogenesis effect on the colon cancer cell line, and this might provide an alternative treatment option for anti-cancer treatment.

Angiogenesis Inhibitors↗
PubMed2003

Irinotecan (CPT11) plus high-dose 5-fluorouracil (5-FU) and leucovorin (LV) as salvage therapy for metastatic colorectal cancer (MCRC) after failed oxaliplatin plus 5-FU and LV: a pilot study in Taiwan.

BACKGROUND: Irinotecan (CPT11) has established activity against advanced colorectal cancer without cross-resistance with 5-fluorouracil + leucovorin-based therapy. We conducted this pilot study to evaluate the efficacy and tolerance of combination treatment with irinotecan and 5-fluorouracil (5-FU) for patients in whom combination treatment with oxaliplatin with 5-FU + leucovorin has failed. METHODS: Patients were enrolled in this study after oxaliplatin treatment had failed. The treatment protocol consisted of CPT11 (180 mg/m(2) for 90 min) on day 1 and a 2 h infusion of 200 mg/m(2) leucovorin followed by 400 mg/m(2) 5-FU as an intravenous bolus injection plus a 22 h continuous infusion of 600 mg/m(2) 5-FU. This regimen was repeated for two consecutive days every 2 weeks. RESULTS: A total of 18 patients were eligible for this study and in total 144 cycles of therapy (median eight cycles) were given to these patients. Four patients (22.2%; 95% CI: 8-36.4%) achieved an objective response of partial remission (PR) and an additional seven obtained stable disease (SD) status or minor response. The median duration of response was 8 months and 14 patients were alive at the end of the study. Hematological toxicity (neutropenia) was the most common serious side effect (29.2%), followed by gastrointestinal effects (diarrhea, 28.5%). Grade II-III diarrhea was experienced for at least one cycle by each patient. CONCLUSIONS: The results of treatment for patients after oxaliplatin failure are encouraging and this treatment protocol is also well tolerated by previously heavily treated patients.

Adult↗
PubMed2003

Loss of heterozygosity and DNA aneuploidy in colorectal adenocarcinoma.

BACKGROUND: This study evaluated the relationship between DNA aneuploidy and loss of heterozygosity (LOH) at different genetic loci in colorectal adenocarcinoma. METHODS: A total of 112 patients with surgically removed colorectal adenocarcinoma in Taipei Veterans General Hospital from January 1999 to July 2001 were included in this study. The pattern of DNA ploidy was determined with DNA flow cytometry, and the LOH of various genetic loci was determined with fluorescence polymerase chain reaction and denaturing gradient gel electrophoresis. The relationship between DNA ploidy, LOH of various genetic loci, and clinicopathologic variables was analyzed with the chi(2) test with Yates' correction as well as by multivariate binary logistic regression analysis. RESULTS: Seventy-one (63.4%) of the 112 carcinomas had DNA aneuploidy. The DNA aneuploidy was not associated with any clinicopathologic variable. Ninety-one tumors (81.3%) exhibited LOH in at least one genetic locus. In the univariate analysis, the DNA aneuploidy was associated with LOH of Tp53-penta, D8S254, D5S346, and high-frequency LOH (P =.001, P =.016, P =.041, and P <.001, respectively). In the multivariate analysis, the most significant factor influencing DNA aneuploidy was D8S254, followed by Tp53-penta, high-frequency LOH, and D5S346. CONCLUSIONS: DNA aneuploidy is strongly associated with LOH at specific genetic loci.

Adenocarcinoma↗
PubMed2003

A randomized prospective trial of bowel preparation for colonoscopy with Fortrans compared with bisacodyl.

BACKGROUND: An empty and adequate clean colon is a prerequisite of diagnostic or therapeutic colonoscopy. Our aim is to assess the efficacy and tolerance of bowel preparation for colonoscopy with Fortrans (polyethylene glycols) versus oral bisacodyl. METHODS: One hundred and four consecutive patients scheduled for colonoscopy were prospectively enrolled and allocated to Fortrans group or bisacodyl group by block randomization. RESULTS: Ninety-four patients were included for final analysis. Forty-five patients underwent preparation with Fortrans. The efficacy and tolerance of colon preparation were similar with both methods (p = 0.102, p = 0.202). The latency before the first bowel movement and total preparation time were shorter with Fortrans than with bisacodyl (p = 0.0001 and 0.001, respectively). Statistically significant differences were noted in changes of body weight, serum levels of sodium and calcium in patients taking bisacodyl (p = 0.049, 0.015, and 0.038, respectively). The taste of Fortrans was rated significantly better than that of bisacodyl (p = 0.002). Patients experienced more abdominal discomfort completing preparation with bisacodyl (p = 0.002). CONCLUSIONS: Fortrans and bisacodyl are equally effective and well tolerated in preparation for colonoscopy. However, Fortrans preparation takes less time and provides a better taste with less abdominal discomfort and less change in body weight as well as serum levels of sodium and calcium than bisacodyl preparation.

Bisacodyl↗
PubMed2003

A potential alternative treatment of uncomplicated painful diverticular disease by trans-colonoscopic irrigation technique: a preliminary report.

BACKGROUND: Colonic diverticular disease is a common disorder in elder patients. Medical treatment was usually recommended as the first line management for this disease. However, the recurrence rate of such disorder is still high. In patients with severe complications such as abscess or fulminant inflammation, non-invasive diagnostic examination, abdominal CT scan for example, is recommended. Its most common symptom is repeated abdominal pain with disturbance of bowel habit. Many patients are found to be with diverticular disease only after colonoscopic examination. The aim of this study is to introduce a new irrigation-draining method and to evaluate its efficacy in treatment of uncomplicated painful colonic diverticular disease. METHODS: To reduce the risk of recurrence of acute diverticulitis and other severe complications, we introduce a transcolonoscopic irrigation technique for patients of uncomplicated diverticular disease by flushing out the obstructed fecalith from the diverticular sac in order to improve the drainage from the obstructed diverticular sac. RESULTS: Thirty-two patients of uncomplicated painful diverticular disease with obstructed fecalith impacted were treated by this technique. Clinical symptom improved in all of them and no complications developed during the mean follow-up period of 46 months. CONCLUSION: The results of this preliminary study suggest that this technique accomplished in the colonoscopic examination without additional therapeutic procedures. It provides another potential alternative to the conventional medical treatment for patients with uncomplicated diverticular disease.

Abdominal Pain↗
PubMed2003

Retained rectal foreign bodies.

BACKGROUND: Retained rectal foreign bodies have been encountered more frequently and present a dilemma for management. Most of the reports on these cases were documented in the form of case report and from Western countries. The present study was a review on the authors' experiences in such cases. METHODS: Data from January 1979 to January 2000 were extracted from a computerized database of Taipei Veterans General Hospital. The clinical features, treatment strategies and outcomes were analyzed. RESULTS: Ten male patients (mean age: 57.0 years) with 12 presentations of retained rectal foreign bodies were collected. Glass bottles and vibrators were the most common objects encountered, while anal eroticism was reported as the reason for insertion in 50% of the cases. The majority of the objects were extracted by non-surgical methods through either anoscope (n = 4), rigid sigmoidoscope (n = 2) or colonoscope (n = 1). Obstetric forceps was utilized to remove an incarcerated bowling bottle. Emergent laparotomies were performed in cases with overt peritonitis (n = 2), pelvic sepsis (n = 1) and an impacted high-lying glass bottle. Minor complications, such as mucosal abrasion or superficial tear, were found in 62.5% of the non-surgically treated cases. Delayed bleeding was found in 2 of them. There was no mortality in our series. CONCLUSIONS: Despite its rarity, the retained rectal foreign body had varying clinical features. Most of the uncomplicated rectal foreign bodies could be simply extracted transanally under adequate anesthesia. Fiberoptic colonoscopic extraction provided an alternative choice. Open surgery should be reserved only for those patients with overt peritonitis or pelvic sepsis.

Adult↗
PubMed2002

Change in anal continence after surgery for intersphincteral anal fistula: a functional and manometric study.

BACKGROUND AND AIMS: Dividing or "laying open" of the tract for intersphincteral type anal fistula is simple and effective and entails low risk of complication, but little is known of the functional and manometric results. This study assessed the clinical and manometric effect of this surgery on anal sphincter function. PATIENTS AND METHODS: The study examined 45 adults undergoing surgical treatment for intersphincteral fistula. We administered the questionnaire for continence score and performed anorectal manometry before the operation and at least 6 months after the operation. The operative method was laying open of the fistula tract and trimming the redundant anoderm for adequate drainage of the wound in all cases. RESULTS: There was a significant decrease in maximal resting anal pressure and in resting pressure throughout the distal 2 cm of the anal canal after operation. The maximal contractile pressure after operation was similar to that before operation. Continence control was significantly poorer in women and patients who had lower preoperative resting pressure. Multivariate analysis showed lower preoperative resting pressure to be the only independent factor for impaired continence control after fistula surgery. CONCLUSION: Although laying open of the fistula tract is a simple and effective therapy for intersphincteral type anal fistula, it should be more conservative for patients with low resting anal pressure.

Adult↗
PubMed2002

Comparison between straight and J-pouch coloanal anastomoses in surgery for rectal cancer.

PURPOSE: This study was designed to compare the long-term results of straight and J-pouch coloanal anastomoses after resection of rectal cancers located in the critical position of 5-6cm from the anal verge. METHODS: The subjects of this study were 81 patients who underwent radical resection of rectal cancers located 5-6 cm from the anal verge, followed by straight or J-pouch coloanal anastomosis, performed in 41 and 40 patients, respectively. Careful clinical and manometric follow-up was conducted and the results were compared. RESULTS: There were no differences in the incidence of local recurrence, the disease-free survival rate, postoperative stool frequency, continence, sphincter pressures, or functional length between the two groups. Both groups had a high incidence of clustering or fragmented defecation; however, the J-pouch patients had better urgency control, a greater capacity before feeling the urge to defecation, superior rectal tolerance, and better compliance. CONCLUSIONS: Both straight and J-pouch coloanal anastomoses are oncologically and functionally acceptable for the treatment of rectal cancer located 5-6cm from the anal verge, but the J pouch has slight superiority in urgency control, as a result of larger urge threshold and tolerable volume, and better compliance. The reason for the high incidence of clustering defecation in both groups needs to be investigated.

Aged↗
PubMedDate not supplied

Epiploic appendagitis of the rectosigmoid junction: demonstration with transrectal sonography.

A 24-year-old man presented with lower abdominal pain that had been present for 18 hours. Physical examination revealed mild tenderness in the lower abdomen. Digital rectal examination revealed a tender point approximately 9 cm above the anal verge. Transrectal sonographic examination demonstrated an ovoid echogenic noncompressible mass surrounded by a hypoechoic halo attached to the wall of the rectosigmoid junction. A diagnosis of epiploic appendagitis was made on the basis of sonographic findings and was subsequently confirmed with contrast-enhanced CT.

Abdominal Pain↗
PubMedDate not supplied

CA19-9 as the most significant prognostic indicator of metastatic colorectal cancer.

BACKGROUND/AIMS: Colorectal cancer is the third leading cause of cancer-related mortality in Taiwan. We became interested in searching for the factors predictive of survival. Serum CA19-9 (carbohydrate antigen 19-9) level has been reported as a factor predictive of survival in patients with colorectal cancer. A few articles have reported that patients with metastatic colorectal cancer who have normal (< or = 37 U/mL) serum CA19-9 levels survived significantly longer than those with higher serum CA19-9 levels. However, these reports are contradictory and lack definite conclusions. This study was carried out in an effort to evaluate the prognostic significance of serum CA19-9 levels in patients with metastatic colorectal cancer in Taiwan. METHODOLOGY: Between 1991 and 1994, a total of 128 patients with histologically confirmed metastatic colorectal cancers were evaluated retrospectively at Veterans General Hospital-Taipei. All patients had measurable metastatic lesions and life expectancies of more than 3 months. 5-Fluorouracil-based chemotherapy, either in a weekly bolus regimen or a monthly 5-day bolus schedule, were administered to all of them. Data on age, sex, performance status, location of primary tumor, extent of metastases, site of metastases, histological differentiation, serum CEA (carcinoembryonic antigen) and CA19-9 levels were analyzed before chemotherapy to determine their association with survival. Blood samples for CEA and CA19-9 measurement were analyzed using the radioimmunoassay method. Multivariate analysis by the Cox's proportional hazards regression model was performed to determine independent prognostic factors among all of the possible variables. RESULTS: By univariate analysis, serum CA19-9 levels (P < 0.001) and performance status of the patients (P = 0.022) were identified as prognostic factors, while age, sex, location of primary tumor, site of metastasis, histological differentiation, and pre-treatment serum CEA levels were not considered significant. By multivariate analysis, serum CA19-9 levels (P < 0.001) and performance status of the patients (P = 0.014) were still found as independent prognostic factors of these patients. CONCLUSIONS: The data from our study indicate that serum CA19-9 level is the most significant prognostic indicator of patients with metastatic colorectal cancer. It is recommended that stratification for further clinical trials for patients with metastatic colorectal cancer should be carried out according to serum CA19-9 levels.

Adenocarcinoma↗
PubMedDate not supplied

Tumor marker CEA in monitoring of response to tegafur-uracil and folinic acid in patients with metastatic colorectal cancer.

BACKGROUND/AIMS: The assessment of response to chemotherapy of solid tumors is generally made by measurement of tumors visualized by imaging, commonly computed tomography scanning. However, response assessment based on imaging is not always feasible because patients often have disease not measurable by imaging study, such as diffuse peritoneal dissemination. Furthermore, response assessment by imaging is expensive and time consuming. This study was carried out in an effort to evaluate the correlation between serial change on imaging and on CEA (carcinoembryonic antigen) levels for assessing chemotherapeutic response of patients with metastatic colorectal cancer. METHODOLOGY: Between May 1998 and August 1999, a total of 40 patients with metastatic colorectal carcinoma were enrolled in this study. All the patients had to have measurable lesions. Oral tegafur-uracil 300 mg/m2/day and folinic acid 60 mg/day were administered concurrently for four weeks, repeated every five weeks, as the first-line treatment. Tumor marker CEA was examined before and during the whole course of treatment. Response based on CEA assessment was defined as a more-than 50% drop in serum CEA level for more than four weeks. The correlation between serial change on CEA and on imaging for assessing chemotherapeutic response was evaluated. RESULTS: Forty patients received a total of 318 courses of treatment and a response rate of 32.5% (95% confidence interval, 18.0% to 47.0%), including five complete responses and eight partial responses, was achieved by imaging studies. The pretreatment CEA levels were elevated beyond the normal cut-off value in 34 (85%) patients. The response rate evaluated by CEA assessment was 42.5% (17/40). Nine responders (22.5%) based on CEA had no remission on imaging. Agreement in assessment by imaging study and by CEA was observed in 20 patients (50%), including eight responders, five stable diseases, and seven progressive diseases. The sensitivity of falling CEA levels in the prediction of true responders on imaging was 62%. The sensitivity of elevated CEA levels for the prediction of progressive disease was 70%. Concerning the diagnostic accuracy, change in CEA levels in the prediction of true responders and progressive disease on imaging were 65% and 85%, respectively. On a follow-up of 24 months, patients with remarkable falling CEA levels survived significantly longer than non-responders (P = 0.0184, log-rank test). CONCLUSIONS: The measurement of CEA levels might be useful in monitoring chemotherapeutic response and in predicting the prognosis of patients with metastatic colorectal cancer. Serum CEA level may be used as a means of monitoring chemotherapeutic response when imaging study is unsuitable for assessing the response in clinical practice.

Adult↗
PubMedDate not supplied

Prospective study of the functional results of transanal endoscopic microsurgery.

BACKGROUND/AIMS: Most clinical research addresses the technological advances and oncological outcomes of transanal endoscopic microsurgery. Our aim was to examine the functional results. METHODOLOGY: From August 1999 to November 2000, 22 Taiwanese patients (14 men, 8 women; median age, 68 years) undergoing transanal endoscopic microsurgery were prospectively examined. Functional questionnaires and anorectal manometry were assessed before surgery and at 2 weeks, 6 weeks, 3 months, and 1 year. RESULTS: The median distance from the anal verge to the tumor was 10 cm. The median tumor diameter was 2.0 cm. The median duration of surgery was 120 minutes. No surgical mortality or morbidity and no local recurrence occurred during a median follow-up of 23 months. The mean stool frequency and consistency were significantly better at 3 months after surgery than before surgery. The maximal resting pressure significantly decreased after surgery. The maximal contraction pressure and maximal tolerated volume were significantly lower at 2 and 6 weeks than before surgery; these values recovered at 1 year. CONCLUSIONS: Transanal endoscopic microsurgery is safe for the cure of benign tumors and the palliative excision of malignant tumors in middle and upper rectum. Anorectal function was preserved and improved, though some anorectal manometric parameters changed over time.

Adenocarcinoma↗
PubMedDate not supplied

Long-term outcome of anastomosis leakage after curative resection for mid and low rectal cancer.

BACKGROUND/AIMS: The aim of this study was to evaluate the relationship of the disease recurrence and prognosis of rectal cancer with anastomosis leakage after curative low anterior resection. METHODOLOGY: The records of 566 patients with primary rectal adenocarcinoma in the Veterans General Hospital-Taipei, Taiwan between 1991 and 1997 were reviewed. Patients who did not have anastomosis (abdominoperineal resection 72, Hartmann's operation 15), did not have curative resection (62) or expired within 30 days after operation (11) were excluded from the study. Another 34 patients were excluded because they did not visit our clinic or could not be reached by telephone or questionnaire after operation. 372 patients who received restorative curative resection with a colorectal anastomosis were analyzed. The product-limit method (Kaplan-Meier) and Cox proportional hazard model were used to analyze survival rate and tumor recurrence. RESULTS: Twenty-five out of the 406 patients had anastomosis leakage after the operation. The 5-year disease-free, local recurrence-free survival of the leakage group (32.5%, 58.7%) was significantly lower than that of the non-leakage group (71%, 88.3%). The multivariate analysis showed TNM staging (p = 0.0001) and histological differentiation (p = 0.0002) were associated with overall tumor recurrence. The factors affected local tumor recurrence were TNM staging (p = 0.006) and anastomosis leakage (p = 0.014). CONCLUSIONS: These results suggested that anastomotic leakage after curative rectal surgery is associated with the local tumor recurrence-free survival rate even after adjusting for stage.

Actuarial Analysis↗
PubMedDate not supplied

Prognostic value of DNA ploidy patterns of colorectal adenocarcinoma.

BACKGROUND/AIMS: The significance of prognostic value of DNA ploidy patterns of colorectal cancer has not yet been fully understood. The present study was designed to determine the prognostic value of DNA ploidy patterns for colorectal adenocarcinomas after resection. METHODOLOGY: We have prospectively collected tumor specimens from 420 patients with colorectal cancer since 1996. The DNA ploidy patterns were determined with the use of DNA flow cytometry. The correlation of DNA ploidy pattern and various characteristics of tumors and the prognostic significance of DNA ploidy patterns were evaluated by univariate as well as Cox's proportional hazard model. The disease-free survival curves were calculated with Kaplan-Meier's analysis, and the survival difference was determined by log-rank test. RESULTS: DNA ploidy patterns were diploid in 115 (27.4%) and aneuploid in 305 patients (72.6%). The pattern of DNA ploidy did not correlate with age, gender, location, differentiation, and stage of the tumors. In 146 patients who were followed up for at least 2 years, the disease-free survival curves were similar between the diploid and aneuploid group. Multivariate analysis disclosed that tumor staging was associated with the survival of patients but the DNA ploidy pattern had no prognostic significance. CONCLUSIONS: The DNA ploidy pattern was not a significant prognostic factor in short-term follow-up.

Adenocarcinoma↗
PubMedDate not supplied

EIA versus RIA in detecting carcinoembryonic antigen level of patients with metastatic colorectal cancer.

BACKGROUND/AIMS: Little literature exists comparing the differences between enzyme immunoassay (EIA) and radioimmunoassay (RIA) in the detection of serum carcinoembryonic antigen (CEA) levels of patients with metastatic colorectal cancer. Because EIA has the advantage of avoiding the use of radioisotopes, the potential of using EIA instead of RIA in detecting CEA of patients with colorectal cancer is of interest to us. METHODOLOGY: Between March and August 2001, a total of 120 blood specimens, including 60 specimens from patients with metastatic colorectal cancer and another 60 from patients with non-malignant diseases, were examined in this study. Serum CEA levels were examined by EIA and RIA methods in parallel. The CEA-EIA tests were done using EIA kits manufactured by Abbott Laboratories at Illinois in the United States. Comparison was done with the conventional CEA-RIA tests using RIA kits manufactured by CIS laboratory at France. The blood samples were sent to Veterans General Hospital-Taipei for EIA and RIA determination. The cut-off value for CEA was set at 5.0 ng/mL. RESULTS: The correlation between the Abbott-EIA and the CIS-RIA methods in detecting serum CEA levels was high. The results give a correlation coefficient of 0.992 with a linear regression line y=0.975 x + 0.215 (p<0.0001). Agreement in the Abbott-EIA and CIS-RIA tests in diagnosis was observed in 113 patients (94%), including 53 positive (>5 ng/mL) and 60 negative (<5 ng/mL) in both tests. The sensitivity was similar in both assays (83% vs. 80%) at a cut-off level of 5 ng/mL. The ability to discriminate between colorectal cancer and non-malignant diseases was good in both assays (p<0.001). The specificity and positive predictive value were slightly higher with the Abbott-EIA method compared with CIS-RIA assay (92% vs. 83% and 91% vs. 83%, respectively). The Abbott-EIA method achieved a similar diagnostic accuracy to CIS-RIA method (88% vs. 82%). CONCLUSIONS: These data suggest that the Abbott-EIA has similar diagnostic power to CIS-RIA in the measurement of CEA levels of patients with metastatic colorectal cancer, with an additional advantage of avoiding the use of radioisotopes. We believe that ELA has the potential to replace RIA in the measurement of CEA in clinical practice.

Adult↗
PubMedDate not supplied

Is decrease of tumor volume correlated with stage change after preoperative concurrent chemoradiotherapy?

BACKGROUND/AIMS: The significance of tumor volume and its change after concurrent chemoradiotherapy (CCRT) was evaluated. METHODOLOGY: Standard-dose external radiation and oral UFUR plus leucovorin were used to treat 30 middle and lower rectal adenocarcinoma patients. Volume of tumor calculated from images obtained by dynamic MRI of the rectum before and after CCRT was compared to pathological results after definite resection and other clinical data. RESULTS: The T-stage in 15 patients (50%), the N-stage in 13 (72.2%), and overall, the TNM stage in 18 (60%), were downstaged, including 7 (23.3%) with complete responses (CR). Volume of tumor before CCRT (Vpre) and after CCRT (VPost) was 10.3+/-6.1cm3 and 4.2+/-2.2cm3, respectively, and VPre correlated with initial T stage, N stage, age, and location. The net decrease ratio (NDR) of tumor volume was related to Vpre and initial T stage. As to the downstaging effect, VPre was related to incidence of CR; NDR was related to the downstaging of the N stage. CONCLUSIONS: All tumors showed volume reduction after CCRT, but the downstaging benefits were not in proportion to the size change. Initially larger tumors had higher ratios of volume reduction, and smaller tumors had higher chance of CR.

Adenocarcinoma↗