Rectosigmoid Adenocarcinoma Research Articles

Isolated Metacarpal Bone Metastasis from Advanced Rectosigmoid Carcinoma

Distant metastasis is a common sequelae of stage III colorectal adenocarcinoma. Liver and lungs are the most common sites for distant metastases, but, metastases to extremities are very rare. We report a case of rectosigmoid adenocarcinoma, which metastasizes to left first metacarpal bone, which is the first occurrence in our experience. The investigations and management of the patient are discussed.

Systematic screening for occult cancer in elderly patients with venous thromboembolism: a prospective study

Cancer is an established risk factor for venous thromboembolism (VTE) and the incidence of cancer increases in the elderly. The benefit of screening for occult cancers in this population is still not clear. To evaluate a systematic screening programme for cancer in elderly patients with VTE. This was a prospective study with a 12-month follow-up period. It was conducted in a single centre in consecutive patients over the age of 70 years who had a confirmed diagnosis of VTE. Predefined non-invasive screening techniques for cancer with clinical, laboratory (including tumour markers) and radiological investigations (abdominal ultrasound, chest X-ray and a thoraco-abdominopelvic computed tomography scan) were evaluated. Fifty patients with a median age of 80 years (range: 70 to 94 years) were included. One patient was diagnosed with chronic lymphocytic leukaemia at inclusion and cancers were found in three other patients during the follow-up period (rectosigmoid adenocarcinoma with hepatic metastases, hepatocellular carcinoma and gastric adenocarcinoma). Only one of the four cancers could have been treated at an earlier stage. The mortality rate of the entire cohort after 12 months was 28%. Two patients died as a direct consequence of cancer. In this study of elderly patients, a non-invasive screening strategy did not detect several cancers that were subsequently overt clinically. A full history, clinical examination and routine laboratory investigations might be the optimal first-line strategy to detect cancer after the diagnosis of VTE in elderly patients, but regular clinical examinations during follow up are warranted.

Extended Retroperitoneal Necrotizing Fasciitis with Genital Involvement, Resembling Fournier Gangrene

Necrotizing fasciitis is a serious infection that originates in the subcutaneous tissues. Although many reports have been published about necrotizing infections of other anatomical sites, retroperitoneal necrotizing soft tissue infection is a rare entity that has been described in only a few case reports. The etiology and clinical course of retroperitoneal necrotizing fasciitis can be variable and it is often difficult to identify the etiology of the infective process. We report a 58-year-old man with rapidly progressive, gas-producing, necrotizing inflammation in the retroperitoneum, complicated with genital involvement resembling Fournier gangrene. The patient was managed successfully by aggressive drainage, debridement, and sequential laparotomies to track and control the extensive necrosis of the retroperitoneum and perineum, in addition to systemic care to control sepsis. After his general condition stabilized, early rectosigmoid adenocarcinoma was identified and resected curatively. He remained well at follow up, six months after discharge. In retrospect, the trigger of the disease process was unclear. Although it was believed possibly to be due to the colon lesion, adenocarcinoma of the rectosigmoid colon was identified and the patient was managed successfully. Similar to necrotizing infections at other anatomical sites, early diagnosis and timely surgical intervention and systemic antimicrobial therapy are mandatory for treating patients with retroperitoneal necrotizing fasciitis.

Diffusion-Weighted Imaging of the Rectosigmoid Colon

The aims of this study were to determine and evaluate the apparent diffusion coefficient (ADC) values of the rectal wall for identifying inflammatory bowel disease (IBD) and rectosigmoid (rectum and sigmoid colon) malignancies. Diffusion-weighted magnetic resonance imaging (DWI) findings of 23 patients (mean age, 57 years) consisting of 14 patients with rectosigmoid adenocarcinomas and 9 patients with IBD (6 with ulcerative colitis and 3 with Crohn disease) were retrospectively reviewed. In addition, 30 healthy controls (mean age, 45 years) were enrolled in the study. Diffusion-weighted imaging was performed with b factors of 0, 500, and 1000 s/mm2. The mean (SD) ADC values of the control, IBD, and rectosigmoid adenocarcinoma groups were 1.47 (0.19) x 10(-3) mm2/s, 1.37 (0.12) x 10(-3) mm2/s, and 0.97 (0.14) x 10(-3) mm2/s, respectively. Among the patients with IBD, 2 were in the active, and the rest were in the inactive period, with mean (SD) ADC values of 1.21 (0.08) x 10(-3) and 1.42 (0.09) x 10(-3), respectively. The ADC values of the normal rectum and rectosigmoid malignancy group and rectosigmoid carcinoma and IBD groups were significantly different (P < 0.01). A cutoff value for carcinomas of 1.14 x 10(-3) mm2/s yielded a sensitivity and specificity of 93.3% and 93.3%, respectively. Our preliminary findings show that quantitative DWI may be able to differentiate the normal rectum from neoplastic involvement, in addition to distinguishing between inflammatory and neoplastic involvements. However, radiologists should be aware of possible overlaps that may lead to misdiagnoses when DWI is used alone.

Frequency and etiology of solitary hot spots in the pelvis at whole-body positron emission tomography/computed tomography imaging

Purpose To determine the frequency and etiology of a single hypermetabolic focus within the pelvis with no other areas of increased 18-fluorodeoxyglucose (FDG) uptake in the reminder of the whole body in an oncological population. Method and Materials We retrospectively examined the first 700 whole-body PET/CT scans performed at our institution for baseline staging or follow-up of cancer and identified all patients with a solitary focus of increased FDG uptake in the pelvis. All available medical records and imaging findings in these patients were reviewed in order to determine the etiology of increased FDG uptake. Results Eight (1.1%) of the 700 patients had a solitary hot spot in the pelvis at positron emission tomography (PET)/computed tomography (CT) imaging, consisting of seven of 380 women and one of 320 men. In the seven women, increased FDG uptake was due to physiological endometrial uptake ( n=2), leiomyoma ( n=1), corpus luteum cyst ( n=1), physiological ovarian uptake ( n=1), urinary leak ( n=1), and nonspecific colitis ( n=1). In the man, uptake was due to recurrent rectosigmoid adenocarcinoma. None of the 700 patients was found to have metastatic disease in the pelvis. Conclusion Isolated pelvic hot spots at PET/CT imaging in an oncological population are not common and usually benign; physiological endometrial or ovarian uptake is the single commonest cause.

Survival and treatment trends of rectal cancer patients in a population with suboptimal local control

Aim To explore trends in rectal cancer survival in Manitoba, particularly in patients where local control was an issue. Method Patients diagnosed with rectal or rectosigmoid adenocarcinoma from 1985 to 1999 were included. Demographic, treatment and mortality information were abstracted from the registry. Relative survival was examined for all patients for the periods 1985–1989, 1990–1994 and 1995–1999, and subsequently limited to those who underwent major surgery (Hartmann's, anterior, and abdominal perineal resection). Results Of the 2925 patients identified, 2163 (74%) had undergone a major surgery. Five-year relative survival was 46%, 54% and 53% for all patients for the three periods, respectively; major surgery results were 53%, 59% and 60%. Radiotherapy was used in 32% of cases in 1985–1989 and in 40% of cases in 1995–1999. Chemotherapy was used in 13% of cases in 1985–1989 and in 37% of cases in 1995–1999. Conclusion Consistent with other studies, overall rectal cancer survival in Manitoba has improved since 1985. Better local control, as suggested in other studies, does not appear to be a major factor in that improvement. Future work should include review of the local control strategy in Manitoba and factors to explain the improved survival.

Trends in rectal cancer survival in relation to the local control strategy

13536 Background: The Swedish Rectal Cancer Trial showed improved survival with improved local control due to adjuvant radiotherapy. Improved survival in several population-based studies, credited to improved local control due to quality assurance programs involving surgery, ± radiotherapy, has also been reported. In Manitoba (Canada) local control in rectal cancer was suboptimal in the mid 1990’s (local recurrence &gt;18% in stage I-III) despite adopting the 1991 NIH chemo-radiotherapy guidelines. There continues to be no quality assurance program. We were interested in exploring trends in survival in Manitoba, particularly in the subset of patients where local control is an issue. Methods: All patients diagnosed with rectum and rectosigmoid adenocarcinoma from 1985 to 1999 were identified from the Manitoba Cancer Registry. Demographic, peri-operative and operative treatment information, and death dates were abstracted from the Registry. Manitoba population and death counts used in the calculation of age-specific relative survival probabilities were obtained from Statistics Canada. Survival was examined for all patients for the time periods of 1985–89, 1990–94 and 1995–99 and subsequently limited to those that underwent major rectal cancer surgery (Hartmann’s, anterior, and abdominal perineal resection). The Ederer II method was used in the estimation of survival probabilities. Results: A total of 3021 rectal cancer patients were identified with 1723 (57.0%) having major surgery. Five-year relative survival for all patients was 48.7%, 49.6% and 56.2% for the three periods respectively. The major surgery group results were 56.9%, 58.1% and 59.7%. Peri-operative radiotherapy was used in 38% of the 1995–99 major surgery group, twice the rate of 1985–89; peri-operative chemotherapy 41%, a ten-fold increase. Conclusions: Consistent with other studies, overall rectal cancer five-year survival in Manitoba has improved since 1985. Smaller survival improvements in the major surgery subgroup, despite increased radiotherapy use (as well as chemotherapy), suggests that better local control was not the major factor in the overall survival improvement, as has been suggested in other studies. Future work should include review of the local control strategy and factors to explain the improved survival. No significant financial relationships to disclose.

A Prospective Comparison of Colonoscopy and Flexible Sigmoidoscopy for the Evaluation of Young Adults with Rectal Bleeding: Preliminary Results

Background: The optimal evaluation of young adults with rectal bleeding remains uncertain. In this investigation, we prospectively compare the findings of flexible sigmoidoscopy (FS) and colonoscopy in young patients with rectal bleeding. Methods: Patients aged 18-40 with a history of bright red blood per rectum were prospectively recruited. Patients were excluded if they had melena, hematemesis, iron-deficiency anemia, a positive fecal occult blood test, a history of inflammatory bowel disease (IBD), a first degree relative with colon cancer under age 50, a barium enema that obligated colonoscopy, or colonoscopy within the previous year. Prior to endoscopy, one investigator interviewed and examined the patient and classified the bleeding as outlet, luminal, or indeterminate. A second investigator, who was blinded to the type of bleeding, then performed an unsedated FS to a maximal insertion of 60 cm, as tolerated by the patient. Sedated colonoscopy was then performed immediately thereafter. Findings were recorded following each procedure. Results: 31 patients were considered for inclusion in the study. 17 patients (3M/14F; age range 21-40 yrs, mean 31 yrs) have undergone the investigation. 5 patients were excluded for: iron-deficiency anemia (3), IBD (1), and first degree relative with colon cancer under age 50 (1). 8 patients declined to participate. 1 patient was referred but could not be contacted. 5/17 (29%) patients were classified as outlet bleeding, 2/17 (12%) as luminal, and 10/17 (59%) as indeterminate. The average depth of insertion on FS was 49 cm (range 17-60 cm). FS findings: hemorrhoids 9/17 (53%); anal fissures 4/17 (24%); anal cryptitis 3/17 (18%); ulcerative colitis 2/17 (12%); rectal ulcer 1/17 (6%); and rectosigmoid adenocarcinoma 1/17 (6%). 2 patients (12%) had a negative FS, and 3 patients (18%) had 2 or more findings on FS. Colonoscopy findings: 1 patient (6%) with indeterminate bleeding had diverticulosis and angiodysplasia on colonoscopy but only cryptitis on FS. The other 16 (94%) patients had no additional findings on colonoscopy besides those on FS. Colonoscopy could not be completed in 3 patients (18%) because of looping or patient intolerance. Conclusions: The preliminary results of this prospective comparison of FS and colonoscopy in young adults with rectal bleeding indicate that colonoscopy rarely yields additional diagnoses, even in patients with luminal or indeterminate type bleeding.

Use of self-expanding metal stents for palliation of rectosigmoid cancer

Background: Patients with large bowel obstruction can be palliated by colostomy or by endoscopic modalities that restore luminal patency. The clinical results of a series of patients with rectosigmoid cancer in whom self-expanding metal stents were inserted at endoscopy are presented. Methods: Thirty-seven patients with symptoms related to obstructive rectosigmoid adenocarcinoma were treated by endoscopic insertion of self-expanding metal stents. Results: Metal stents were correctly placed in 36 of 37 patients (97%) with no immediate complications. Early dislodgment of the stent (within 1 week) was observed in 3 cases. The remaining 33 patients (92%) were followed for a median of 7 months (3 weeks-33 months). In 28 patients (78%) there was long-term restoration of luminal patency and disappearance of obstructive symptoms without further treatments. They experienced no pain, tenesmus, or incontinence during the follow-up period. The incidence of complications (early and late) and the mortality rate related to the procedure were 22% and 3%, respectively. Conclusions: Endoscopic metal stents can be considered a simple and effective solution for long-term palliation of rectosigmoid cancer. (Gastrointest Endosc 2001;53:203-6.)

The National Cancer Data Base report on patterns of care for adenocarcinoma of the rectum, 1985-95.

The Commission on Cancer data from the National Cancer Data Base (NCDB) examining current time trends (1985-1995) in stage of disease, treatment patterns, and survival relating to patients with rectal adenocarcinoma are described in this report. Seven calls for data to hospital cancer registries across the U.S. have yielded a total of 5,850,000 cancer cases for the years 1985-1995 and include 20,461 rectal and rectosigmoid junction adenocarcinoma cases in 1985-1986, 36,007 cases in 1989-1990, and 42,069 cases in 1994-1995. These data represent 24.4%, 44.5%, and 52.5%, respectively, of the estimated cases of rectal and rectosigmoid adenocarcinoma cases diagnosed in the U.S. in each of the 3 respective time periods. Analysis of the data is limited to cases with American Joint Committee on Cancer (AJCC) Stage I-IV disease. Four trends were observed. 1) Stage I disease was diagnosed with decreasing frequency, decreasing from 37.1% of cases with known AJCC stage of disease in 1985-1986 to 33.8% in 1994-1995. 2) There was an increase in the frequency with which local excision was utilized as all or part of the primary treatment for Stage I disease. 3) Stage for stage, there was an increase in the frequency with which anterior/posterior resections were utilized and a corresponding decline in the use of abdominoperineal resections. 4) Multimodal treatment regimens are being used with greater frequency, particularly in patients with Stage II and III disease. The NCDB data have important implications for analyzing cancer treatment and outcome in the U.S. These data suggest that rectal adenocarcinoma is being diagnosed at a later stage, especially among the young and African Americans. The guidelines for colorectal carcinoma screening issued by the American Cancer Society and the American Gastroenterological Association should be promoted more vigorously to increase the proportion of patients presenting with early stage disease and improve overall survival. The increased use of multimodal therapy for the treatment of Stage II and III disease continues.

An Unusual Implantation of a Rectosigmoid Adenocarcinoma into a Hemorrhoidectomy Scar

An Unusual Implantation of a Rectosigmoid Adenocarcinoma into a Hemorrhoidectomy Scar

Fistula between the Hip and the Sigmoid Colon after Total Hip Arthroplasty. A Case Report*

LEVIN, JARED S. M.D.†; RODRIGUEZ, AGUSTIN A. M.D.‡; LUONG, KEVIN M.D.†, BOSTON, MASSACHUSETTS Author Information

A nitrogen-free hypocaloric diet and recombinant human growth hormone stimulate postoperative protein synthesis: Fasted and fed leucine kinetics in the surgical patient

Twelve otherwise healthy patients undergoing elective surgery for resection of rectosigmoid adenocarcinoma were randomly allocated to two groups: one group receiving intravenous dextrose 5% 600 to 800 kcal · d −1 (DX, n = 6) and the other group receiving the same amount of dextrose intravenously plus recombinant human growth hormone (DX + rGH, n = 6). Supplementation with rGH strated on the day of surgery and continued for 5 days after surgery. Protein kinetics were studied in the diet. This regimen was started 3 days before surgery and continued for 5 days after surgery. Protein kinetics were studied over a period of 8 hours in all patients. Following an overnight fast, a primed constant infusion of l-[1- 13C]leucine was maintained for 4 hours (fasted state) and continued for a further 4 hours (fed state) during which 5% beet dextrose (low 13C content) with or without rGH was administered. The isotope studies were performed on the day before surgery and 6 days after surgery. Other measurements included urinary nitrogen excretion, gaseous exchange, and plasma concentrations of insulin, GH, and insulin-like growth factor-I (IGF-I). Addition of rGH to the dextrose diet had a significant positive effect on protein synthesis ( P = .02). Surgery was responsible for a significant increase in postoperative whole-body protein breakdown and synthesis and leucine oxidation ( P < .01), although lesser changes were observed in the DX group. An interaction between rGH and surgery was associated with a significant increase in protein synthesis ( P = .009), but not with changes in either protein breakdown or leucine oxidation. Carbohydrate provision in the form of beet dextrose during the fed state of the isotopic study did not attenuate the significant decrease in protein synthesis ( P = 0.0) or breakdown ( P = .003) either before or after surgery, probably reflecting the absence of nitrogen in the diet. No significant interaction was found between rGH and feeding. These results of leucine kinetics indicate that addition of rGH to a low-dextrose intake in the absence of dietary nitrogen can actually promote protein synthesis. The low levels of leucine oxidation could be explained by the fact that amino acids resulting from protein degradation were directed preferentially toward resynthesis of new proteins rather than to oxidative pathways. There was a significant increase in plasma insulin and GH in the group receiving rGH ( P < .05). The postoperative plasma concentration of IGF-I did not change in the latter group compared with the DX group, in which IGF-I concentration decreased significantly ( P < .05) as part of the response to combined surgery and dietary restriction. Although both IGF-I and insulin are independently capable of stimulating protein synthesis, elevated levels of either hormone or GH itself may primarily modulate protein synthesis, even with a low intake to carbohydrates.

DNA aneuploidy in a case of rectosigmoid adenocarcinoma complicated by ulcerative colitis

A case of Borrmann type IV colorectal adenocarcinoma detected as a complication of long-standing ulcerative colitis is reported. Barium enema and colonoscopy disclosed a stenotic area associated with a tumoral mass and a flat elevated lesion in the rectosigmoid region and a submucosal tumor-like lesion in the rectum. Total colectomy was performed and histological studies demonstrated a moderately differentiated adenocarcinoma accompanied by high- and low-grade dysplasia. DNA ploidy pattern analysis showed aneuploidy in the adenocarcinoma and high-grade dysplasia, but diploidy in the normal and atrophic mucosa and in low-grade dysplasia. DNA aneuploid content was associated with the presence of colorectal carcinoma complicating ulcerative colitis, indicating that DNA content studies should be included in screening programs to detect early colorectal carcinoma following this disease, as a complementary study to histological assessment.

POSTOPERATIVE PROTEIN METABOLISM: EFFECT OF NURSING ELDERLY PATIENTS FOR 24 H AFTER ABDOMINAL SURGERY IN A THERMONEUTRAL ENVIRONMENT

We have studied the effect of intraoperative body heat conservation and 24-h thermoneutrality on postoperative whole body protein turnover using stable isotope methodology in a group of elderly patients undergoing colorectal surgery for rectosigmoid adenocarcinoma. Two groups of eight patients were studied. One group (control, or cold) received routine intraoperative and postoperative care. All patients in the second group (warmed) were maintained at normothermia during anaesthesia and surgery; these patients were nursed after surgery in a warm room (ambient temperature 28-30 degrees C) for a period of 24 h. General anaesthesia, surgical care and nutritional support were similar in both groups. A constant nutritional intake, based on nitrogen 0.1 g kg-1 day-1 and energy 20 kcal kg-1 day-1, was provided orally for 7 days before surgery and i.v. after operation for 4 consecutive days. Whole body protein breakdown and synthesis, as assessed by stable isotope methodology, increased significantly 2 and 4 days after surgery in both groups (P less than 0.01), but the increase in protein breakdown in the warmed group on day 2 was significantly less than that in the cold group (P less than 0.05). The increase in leucine oxidation in the warmed group on the 2nd day after surgery was not significant, and was less than the increase observed in the cold group (P less than 0.05). However, by the 4th day, leucine oxidation was enhanced significantly in both groups (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Endoscopic photodynamic therapy with haematoporphyrin derivative in gastroenterology

Endoscopic photodynamic therapy (PDT) with haematoporphyrin derivative was used in the primary treatment of 69 patients with inoperable gastrointestinal neoplasms. Patients were divided into three groups: 31 with oesophageal squamous cell carcinoma, 17 with adenocarcinoma of the stomach or lower third of the oesophagus and 21 with rectosigmoid adenocarcinoma. After infusion of 2.5–5.0 mg haematoporphyrin derivative per kilogram of body weight, lesions were irradiated using an argon dye laser (632 nm). During a follow-up period averaging 20 months (27.9 months for 35 surviving patients), complete local tumour destruction and negative histology were observed in 32 out of 69 cases. Flow-cytometric analysis of DNA content before and after PDT suggests that a clonal selection occurs in some cases of treatment failure. The results of this open pilot study suggest the potential efficacy of PDT as a curative treatment for selected cases of inoperable gastrointestinal cancers.

Endoscopic photodynamic therapy with hematoporphyrin derivative for primary treatment of gastrointestinal neoplasms in inoperable patients

Endoscopic photodynamic therapy with hematoporphyrin derivative was used in the primary treatment of 54 patients with inoperable gastrointestinal neoplasms. Patients were divided into three groups including 24 with esophageal squamous cell carcinoma, 14 with adenocarcinoma of the stomach or lower third of the esophagus, and 16 with rectosigmoid adenocarcinoma. After infusion of 2.5-5.0 mg hematoporphyrin derivative/kg of body weight, lesions were photoradiated using an argon dye laser with power set at 300-400 mW for 5 min/site. During a follow-up period averaging 14.5 months (range 1-33 months), complete local tumor destruction and negative histology were observed in 24 of 54 cases. The mean recurrence-free period varied from 13.8 to 17.4 months according to groups. Fifteen patients remain alive and disease-free. The results of this open pilot study suggest the potential efficacy of photodynamic therapy as curative treatment for selected cases of inoperable gastrointestinal cancers, possibly in association with locoregional radiotherapy.

Synchronous neoplasms in patients with diminutive colorectal adenomas.

The distribution of synchronous neoplasms was retrospectively analyzed in 220 patients undergoing initial colonoscopic evaluation for colorectal neoplasms. In 159 of the 220 patients, an index neoplasm was present in the rectosigmoid region. Of these 159 patients, 32 had an index rectosigmoid adenoma less than 5 mm in diameter (diminutive), 105 had an index rectosigmoid adenoma greater than or equal to 5 mm in diameter and 22 had an index rectosigmoid adenocarcinoma. Among these patients with different index neoplasms the frequency of synchronous neoplasms was 34%, 53%, and 73%, respectively. The synchronous neoplasm was an adenoma greater than or equal to 5 mm in diameter in 13%, 40%, and 64%, respectively. The synchronous neoplasm was a carcinoma in 0%, 7%, and 5%, respectively. Two or more synchronous neoplasms occurred in 9%, 34%, and 41% of the index neoplasm groups, respectively. Finally, symptoms providing an indication for colonoscopy were present in 31%, 75%, and 86%, respectively. It is concluded that patients with diminutive index adenomas had fewer and smaller synchronous neoplasms (P less than 0.025) than patients with larger adenomas or invasive carcinoma as the index lesion. Thus, total colonoscopy does not appear to be necessary in asymptomatic patients with only diminutive adenomas found at flexible sigmoidoscopy.

Specificity of fibrinopeptide A (FpA) as a marker for gastrointestinal cancers before and after surgery.

In 70 patients affected by gastrointestinal malignancies the plasma fibrinopeptide A (FpA) levels were assessed both before and at various intervals after the operation. At the same time other more commonly used tests of coagulation were carried out. In all the patients plasma FpA levels were shown to be variously elevated, so that they could give useful clues to the diagnosis, treatment, prognosis and follow-up of the gastrointestinal malignancies. In all the patients the coagulation tests fell into the normal ranges. However in the patients affected by recto-sigmoid adenocarcinoma an increase of circulating fibrin degradation products (FDPs) was observed which paralleled the increase of plasma FpA. In conclusion, in gastrointestinal malignancies the increase of plasma FpA levels suggests the cancer-induced start of the coagulation cascade. The assay of this peptide proves to be a reliable marker for these diseases.

Toxicity and antitumor effect of 5-fluorouracil and its rescue by uridine.

The pyrimidine analog 5-fluorouracil (5FU) has been used in the treatment against several solid carcinomas, mainly of the colon, for several decades (1). However, overall response rate is only about 20%, while gastrointestinal and myeloid toxicity are dose-limiting (1). Research on 5FU has been directed towards enhancing 5FU anabolism by combination with e.g. methotrexate (2) or thymidine (3) and towards the development of several analogs of 5FU. One recent analog, Doxifluridine (5′-deoxy-5-fluorouridine, 5’dFUR) showed an improved therapeutic index against a broad range of murine and rat tumors (4,5) and therapeutic activity in human advanced rectosigmoid adenocarcinoma (6).