Improved overall survival among responders to preoperative chemoradiation for locally advanced rectal cancer.

The aim of this study was to determine if the response to preoperative radiation and chemotherapy with continuous infusion 5-fluorouracil (5-FU) was predictive for survival among patients with locally advanced rectal cancer. Preoperative chemoradiation (CTX/XRT) that delivered 45 Gy in 25 fractions over 5 weeks with continuous infusion 5-FU (300 mg/m2/day) was given to 117 patients. The pretreatment stage distribution, as determined by endorectal ultrasound (u), included uT2N0 in 2%, uT3N0 in 47%, uT3N1 in 49%, and uT4N0 in 2% of cases; endorectal ultrasound was not performed in 13% of cases (15 patients). Approximately 6 weeks after completion of CTX/XRT, surgery was performed. Adjuvant chemotherapy, consisting of 400 to 425 mg/m2 of 5-FU plus 20 mg/m2 leucovorin for 5 days, was administered every 28 days for 4 to 6 cycles after surgical resection. Among the 74 patients treated with adjuvant chemotherapy, the preoperative stage of disease was 31 with T3N0 and 43 T3N1. Median follow-up was 46 months (range 2 to 89 months). The pathologic tumor stages were Tis-2N0 in 26%, T2N1 in 5%, T3N0 in 21%, T3N1 in 15%, T4N0 in 5%, and T4N1 in 1%; a complete response (CR) to preoperative CTX/XRT was pathologically confirmed in 32 (27%) of patients. Tumor down-staging occurred in 72 (62%) cases. A sphincter-saving procedure (SP) was possible in 59% of patients. The median DFS and overall survival rates for responders were 46 months and 47 months, respectively; for non-responders these outcome measures were 38 months and 41 months, respectively. Log-rank analysis showed that the distant metastatic-free survival rates improved with any response to CTX/XRT (p < 0.00001), CR to CTX/XRT (p < 0.009) and SP (p < 0.012). Likewise, these parameters also significantly influenced DFS rates (CTX/XRT p < 0.00001; CR p < 0.006; and SP p < 0.008). Control of pelvic disease was influenced by clinical size (p < 0.002) and SP (p < 0.016) on univariate analysis. On multivariate analysis only clinical size (p < 0.002) continued to be a significant factor for local control. Factors on multivariate analysis that resulted in significant improvements in cancer-specific survival included any response to preoperative CTX/XRT (p < 0.017) and administration of adjuvant chemotherapy (p < 0.034). Any response to preoperative CTX/XRT improved distant metastatic-free and disease-free survival rates. Multivariate analysis confirmed that a response to preoperative CTX/XRT predicted for improvements in overall survival among patients with locally advanced rectal cancer. Patients who fail to respond to preoperative 5-FU based chemotherapy given concomitantly with radiation have higher rates of distant metastases with adjuvant 5-FU therapy.

A phase I study. Preoperative UFT/leucovorin and radiation therapy in rectal cancer.

The use of combined modality regimens has been well established in the treatment of stages II and III rectal cancer. The most common chemotherapy regimens used include continuous-infusion 5-FU delivered with the help of a central venous catheter and the use of portable pumps. These regimens are expensive and can potentially develop line problems. The availability of the oral agent UFT in combination with oral leucovorin prompted the development of an all-oral chemotherapy regimen that could be combined with radiotherapy. At The University of Texas M. D. Anderson Cancer Center, we routinely use combined chemotherapy and radiotherapy preoperatively for the treatment of rectal cancers, and decided to conduct a phase I trial in which UFT and leucovorin was used instead of the conventional 5-FU. The preliminary results are encouraging and seem to demonstrate the feasibility of this approach.

Progress in colorectal cancer chemotherapy: how far have we come, how far to go?

Fluorouracil has been the mainstay of treatment for colorectal cancer (CRC) for almost 40 years. Various schedules and biochemical modulators have been investigated in an attempt to improve the therapeutic efficacy of fluorouracil. To date, fluorouracil plus folinic acid represents the standard therapy in CRC for the adjuvant treatment of patients at high risk for relapse and for the first-line treatment of metastatic disease. To gain clinical acceptance, however, oral fluoropyrimidines must confer at least the same survival advantages associated with the optimal intravenous fluorouracil regimens. Irinotecan and oxaliplatin are 2 other novel agents that have mechanisms of action that are uniquely different from those of fluorouracil, with demonstrated activity in patients with fluorouracil-refractory disease. Recent randomised trials comparing fluorouracil plus folinic acid with combinations of either irinotecan or oxaliplatin and fluorouracil plus folinic acid have shown that response rates are improved and time to progression is increased in patients receiving the combination regimens. These regimens are being rapidly introduced in the adjuvant setting, and the role and acceptance of these combination regimens as first-line therapy needs to be defined. Other novel agents being evaluated in the treatment of patients with advanced CRC include oral edrecolomab (monoclonal antibody 17-1A) and tumour vaccines. Future research is focused on enabling clinicians to individualise treatment strategies in patients with CRC, so as to improve clinical outcomes and reduce drug toxicity.

Colorectal cancer: chemotherapy treatment overview.

Fluorouracil (5-FU) has remained the standard therapy for the treatment of advanced colorectal cancer for over 40 years. Unfortunately, only a minority of patients experience objective clinical response. Discussed herein are attempts to improve on the activity of 5-FU by biochemically modulating its action. In addition, novel agents for the treatment of advanced colorectal cancer (oral fluoropyrimidines, oxaliplatin, and irinotecan) are discussed. Oral fluoropyrimidines (UFT plus leucovorin, capecitabine, eniluracil plus oral 5-FU) provide the convenience of oral delivery with a marked reduction in febrile neutropenia and mucositis. Recent randomized trials with these agents have demonstrated therapeutic activity that is comparable with intravenous schedules of 5-FU plus leucovorin. Compared to 5-FU, both oxaliplatin and irinotecan have uniquely different mechanisms of action and have demonstrated clinical activity in patients whose disease has progressed with 5-FU treatment. Combinations of either irinotecan or oxaliplatin plus 5-FU/leucovorin have demonstrated that the addition of these agents to 5-FU/leucovorin improves response rates and time to progression compared to 5-FU/leucovorin alone. Combination chemotherapy regimens with these novel agents are rapidly being introduced into the adjuvant setting.

Prognostic implications of response to preoperative infusional chemoradiation in locally advanced rectal cancer.

BACKGROUND AND PURPOSE: To evaluate the influence of response to preoperative infusional chemoradiation on outcome parameters among patients with locally advanced rectal cancer. MATERIALS AND METHODS: Preoperative chemoradiotherapy, 45 Gy in 25 fractions over 5 weeks with continuous infusion 5-fluorouracil (300 mg/m2 per day), was given to 117 patients. As determined by pretreatment endorectal ultrasound (EUS), 96% of cases were Stage T3, and 51% had EUS evidence of perirectal adenopathy. Surgery was performed approximately 6 weeks after chemoradiation therapy. Postoperatively adjuvant systemic therapy, consisting of 400-425 mg/m2 of 5-fluorouracil plus 20 mg/m2 leucovorin for 5 days, was administered every 28 days for six cycles. Outcome parameters of local control (LC), freedom from distant metastases (DMC), disease-free survival (DFS) and cancer specific survival (CSS) were evaluated relative to primary tumor characteristics. RESULTS: The final post-treatment pathological tumor stages were complete response in 27%, Tis-2 N0 in 26%, T2 N1 in 5%, T3 N0 in 21%, T3 N1 in 15%, T4 N0 in 5% and T4 N1 in 1%. Down-staging occurred in 61% of cases. The pretreatment primary tumor size only influenced rates of local control (P < 0.03) and had no other influence on outcome parameters. Pretreatment evidence of perirectal lymph node involvement had no impact on outcome parameters. Pathologic evidence of nodal involvement did affect DMC (P < 0.002) and DFS (P < 0.003). Pathologic evidence of response did influence freedom from the development of distant metastases (P < 0.004). On pairwise analysis this relationship held only when responders were compared to non-responders. No difference was observed based on the level of downstaging at the primary tumor. Correspondingly, DFS was improved when non-responders were compared to downstaged patients (P < 0.01). Response to preoperative chemoradiation failed to affect rates of LC or CSS. For the group as a whole, adjuvant chemotherapy improved only CSS (P < 0.03). Adjuvant chemotherapy was given to 74 patients, 36 of whom had responded to preoperative chemoradiation. Improvements were only seen in DFS (P < 0.03) when down-staged patients were compared to the non-responders who received adjuvant chemotherapy. In addition, the DFS rates were lower in the non-responder group who received adjuvant chemotherapy even when they were compared to down-staged patients who did not receive adjuvant chemotherapy (P < 0.04). CONCLUSION: Consistent with other reports, disease free survival and subsequent development of distant metastases is reduced in the more than 60% of patients who respond to preoperative infusional chemoradiation. Evidence of response appears more significant than the degree of response. At present, no impact is seen on cancer specific survival rates. Consideration should be given for strategies that base selection of subsequent adjuvant chemotherapy on response to preoperative chemoradiation.

Preoperative UFT and calcium folinate and radiotherapy in rectal cancer.

Protracted infusions of 5-fluorouracil (5-FU) combined with pelvic radiotherapy have been associated with improved survival and decreased local and distant metastases in the adjuvant therapy of rectal cancer. However, this method of 5-FU infusion requires the inconvenience and expense of central venous line placement and care, infusion pumps, and treatment of catheter-related complications. We previously demonstrated that a completely oral therapy with UFT (uracil plus tegafur in a 4:1 molar ratio) plus oral calcium folinate (Orzel) can achieve pharmacokinetic parameters similar to those associated with protracted 5-FU infusions. This trial examines the feasibility of using UFT plus oral calcium folinate both during preoperative pelvic radiation and postoperatively, and shows that patients can be treated safely and effectively with a completely oral chemotherapy program combining UFT plus oral calcium folinate with pelvic radiation therapy.

Phase I trial of uracil-tegafur (UFT) plus oral leucovorin: 28-day schedule.

UFT [Taiho Pharmaceutical Co. Ltd., Tokyo, Japan; (BMS-200604), Bristol-Myers Squibb, Princeton, NJ], a fluorouracil prodrug, is an oral 4:1 molar concentration of uracil plus tegafur. This study examined the dose-limiting toxic effects and maximum tolerated dose of UFT plus leucovorin administered for 28 consecutive days followed by a 7-day rest period. A course of therapy was repeated every 35 days. UFT dose levels examined were 200 mg/m2/day, with planned escalations to 250, 300, 350, and 400 mg/m2/day; the leucovorin dose remained at 150 mg/day. Three patients were initially enrolled at each UFT dose level. The total daily doses of both UFT and leucovorin were divided into three doses administered every 8 hr. Diarrhea became the dose-limiting toxicity at 400 mg/m2/day UFT, with grade 3 diarrhea noted in 2 of the 3 patients receiving that dose. To further define a phase II UFT starting dose, 3 additional patients were entered at the 350 mg/m2 level; 3 of the 6 patients treated at this level developed grade 3 nonhematological toxic effects. No partial or complete responses were observed. The recommended phase II UFT starting dose is 300 mg/m2/day plus 150 mg/day leucovorin. Since neutropenia, significant mucositis, and "hand-foot syndrome" were not observed with UFT plus leucovorin, the toxicity profile of this regimen appears favorable compared with that of intravenous regimens of fluorouracil plus leucovorin. This phase I trial of UFT served as the basis for a phase II trial, current phase III trials, and a national adjuvant therapy trial of UFT for high-risk colon cancer patients.

Prospectively randomized trial of postoperative adjuvant chemotherapy in patients with high-risk colon cancer.

PURPOSE: This study had two major goals: (1) to assess the effectiveness of a regimen of fluorouracil (5-FU) plus levamisole plus leucovorin as postoperative surgical adjuvant therapy for patients with high-risk colon cancer, and (2) to evaluate 6 months versus 12 months of chemotherapy. PATIENTS AND METHODS: Patients with poor-prognosis stage II or III colon cancer were randomly assigned to receive adjuvant chemotherapy with either intensive-course 5-FU and leucovorin combined with levamisole, or a standard regimen of 5-FU plus levamisole. Patients were also randomly assigned to receive either 12 months or 6 months of chemotherapy, which resulted in four treatment groups. RESULTS: Eight hundred ninety-one of 915 patients entered (97.4%) were eligible. The median follow-up duration is 5.1 years for patients still alive. There was a difference among the four treatment groups with respect to patient survival, and a significant duration-by-regimen interaction was observed. Specifically, standard 5-FU plus levamisole was inferior to 5-FU plus leucovorin plus levamisole when treatment was given for 6 months (5-year survival rate, 60% v 70%; P < .01). CONCLUSION: There was no significant improvement in patient survival when chemotherapy was given for 12 months compared with 6 months. When chemotherapy was given for 6 months, standard 5-FU plus levamisole was associated with inferior patient survival compared with intensive-course 5-FU plus leucovorin plus levamisole. These data suggest that 5-FU plus levamisole for 6 months should not be used in clinical practice, whereas 6 months of treatment with 5-FU plus leucovorin plus levamisole is effective.

UFT and leucovorin: a review of its clinical development and therapeutic potential in the oral treatment of cancer.

UFT is an oral antineoplastic drug combining uracil and tegafur in a 4:1 molar ratio. Tegafur acts as a prodrug of 5-fluorouracil (5-FU), being slowly metabolized by cytochrome P450 to 5-FU. Uracil competitively inhibits the metabolism of 5-FU, resulting in increased plasma and tumor 5-FU concentrations. At equimolar doses, higher peak plasma 5-FU concentrations are achieved with UFT plus oral leucovorin with similar systemic 5-FU exposure compared with low-dose continuous 5-FU infusions. The elimination half-life of 5-FU following UFT administration is approximately 7 h compared with 0.2 h with i.v. 5-FU. In phase II studies of UFT plus oral leucovorin for the treatment of advanced colorectal cancer, response rates ranged from 25 to 42%. UFT plus oral leucovorin is well tolerated, with manageable diarrhea being the only dose-limiting toxicity; the regimen is not associated with significant myelosuppression, mucositis, hand-foot syndrome or alopecia. UFT, with or without leucovorin, has also been evaluated alone or in combination with other cytotoxic agents for the treatment of advanced lung, breast and gastric cancers. UFT has also been evaluated as adjuvant therapy for colorectal, breast, gastric, head and neck, and superficial bladder cancers. UFT plus leucovorin offers patients an entirely oral cancer treatment, and appears to provide potential advantages over bolus 5-FU regimens with regard to toxicity and convenience of administration. These benefits should be advantageous in the adjuvant setting, as well as in advanced disease settings in which palliation is an important consideration. Ongoing clinical trials will further define the role of this promising oral treatment regimen.

Phase II study of UFT plus leucovorin in colorectal cancer.

The activity and toxicity of UFT (Tegafur and Uracil) in a 4:1 molar concentration, plus leucovorin (LV), were evaluated in the treatment of 45 patients with advanced, bidimensionally measurable metastatic colorectal carcinoma. Initially 350 and later 300 mg/m2/day, plus 150 mg LV, as administered in divided doses every 8 h for 28 days. After two courses of treatment, responses were evaluated. The overall response rate was 42.2%, with responses observed in liver (n = 18), lung (n = 6), and bone (n = 1). Five of the 7 patients who received 350 mg/m2 UFT experienced prolonged grade 3 diarrhea, resulting in a dose reduction to 300 mg/m2; 9 patients in the 300-mg/m2 group experienced grade 3 diarrhea, vomiting, abdominal cramping, and fatigue. Minor toxic effects included oral mucositis and rash. The oral regimen of 300 mg/m2/day UFT, plus 150 mg/day LV, administered for 28 days appears to have significant activity against metastatic colorectal carcinoma. The treatment is well tolerated; neutropenia did not occur, and oral mucositis was not significant, even though both are characteristic of intravenous schedules of 5-fluorouracil plus LV. The results of this trial constitutes the basis of phase III clinical trials comparing this oral schedule with intravenous 5-FU and LV to compare clinical efficacy, impact on well-being, and cost. In addition, the current National Surgical Adjuvant Breast and Bowel Project (NSABP) adjuvant colon clinical trial (CO-6) will compare this 28-day schedule of UFT plus oral leucovorin with a weekly regimen of intravenous 5-fluorouracil plus leucovorin in the postoperative adjuvant therapy of Dukes' B and C colon cancer patients.

Preoperative combined oral UFT plus leucovorin and radiation therapy for rectal cancer.

Several trials performed in the United States and Europe have demonstrated the efficacy of UFT (uracil and tegafur in a 4:1 molar combination) with oral leucovorin in the treatment of several tumor types, but particularly for advanced colorectal cancer. Phase III studies are under way in the United States to determine whether the combination of UFT with oral leucovorin is as effective as standard treatment, not only in the advanced setting but also in the adjuvant arena as well. This study is an open-label phase I trial to determine the safety of UFT and leucovorin, both given orally three times daily during concurrent fixed doses of pelvic radiotherapy, and to determine the safety of UFT plus oral leucovorin administration after pelvic radiotherapy, chemotherapy, and surgery. Standard treatment at M. D. Anderson Cancer Center for patients with T3, T4, and/ or > N1 rectal carcinoma is a preoperative continuous-infusion of fluorouracil (5-FU) with radiation therapy followed by four courses of 5-FU/ leucovorin postoperatively. Data suggest that UFT and leucovorin may offer a well-tolerated, fully oral treatment option that could be more convenient for patients. The trial presented herein provides data relative to the feasibility of preoperative oral UFT and leucovorin chemotherapy given during radiation therapy, and oral UFT and leucovorin chemotherapy following surgery in the treatment of patients with rectal cancer. This study is anticipated to serve as a pilot to develop an investigational treatment arm for a randomized trial of preoperative treatment of patients with rectal cancer.

Phase I trial of sulindac plus 5-fluorouracil and levamisole: potential adjuvant therapy for colon carcinoma.

Epidemiological studies indicate that nonsteroidal anti-inflammatory agents may reduce colorectal cancer incidence and mortality. Moreover, sulindac has been shown to attenuate the growth and progression of colonic neoplasms in an experimental model of colon carcinoma and in patients with familial adenomatous polyposis. To determine whether sulindac (300 mg/day) would increase toxicity associated with 5-fluorouracil (5-FU) and levamisole, 15 patients with advanced colorectal cancer were treated. Median treatment duration was 3 (range, 0.6-6.0) months, and median age was 56 years (33% >/= 60 years). All patients had failed prior 5-FU-based therapy, had measurable disease, and were evaluable for toxicity. Grade III/IV granulocytopenia occurred in four patients; three patients had received prior pelvic irradiation resulting in a predisposition to myelosuppression. Two patients developed grade III anemia, and occult gastrointestinal bleeding was suspected in one. No other grade II or greater gastrointestinal or other nonhematological toxicity occurred. One patient had a partial response, 3 patients had disease stabilization, and 10 patients progressed on study. Our results indicate that sulindac does not significantly increase short-term toxicity associated with 5-FU and levamisole. To determine whether sulindac increases the efficacy of adjuvant chemotherapy, we propose a phase III randomized trial in patients with lymph node-positive colon cancer.

Low serum alpha-fetoprotein level in patients with hepatocellular carcinoma as a predictor of response to 5-FU and interferon-alpha-2b.

BACKGROUND: A Phase II clinical trial was conducted to evaluate the efficacy of intravenous fluorouracil (5-FU) and subcutaneous recombinant interferon-alpha-2b (rIFN-alpha-2b) in the treatment of hepatocellular carcinoma (HCC) and to define factors that might be predictive of a response to treatment. METHODS: Twenty-nine patients were registered on the protocol. 5-FU was administered as a continuous intravenous (i.v.) infusion (dose = 750 mg/m2) for 5 consecutive days. rIFN-alpha-2b was administered subcutaneously (SC) (dose = 5 x 10(6) um/m2) once a day on days 1, 3, and 5 of the 5-FU infusion. The treatment was repeated at 14-day intervals. Responses were assessed at the end of one course of therapy, which was equivalent to four treatments. RESULTS: Of the 28 patients evaluable for response, 5 (18%) had a partial response, and 1 (4%) had a minor response. Responses lasted from more than 2 to more than 24 months (median, 11.5 months). Ten (36%) patients experienced no response, and 12 (43%) had progressive disease. The 6 responders were part of a group of 16 patients who had pretreatment levels of serum alpha-fetoprotein (AFP) of 50 ng/ml or less and a group of 8 whose tumors involved 50% or less of the liver parenchyma. Mucositis, which occurred in 54% of the patients, was the most common toxicity associated with the treatment regimen. Diarrhea and dermatitis were observed in 16% and 17% of the patients, respectively; fatigue, thrombocytopenia, granulocytopenia, neurologic toxicity, and nausea and vomiting were not commonly seen. CONCLUSIONS: The regimen of i.v. 5-FU and SC rIFN-alpha-2b was well tolerated and induced durable partial response in 31% (5 of 16) of patients with HCC who had low levels of serum AFP and in those with 50% or less of liver replacement. In contrast, the treatment regimen was ineffective in patients with HCC who had high levels of serum AFP or extensive liver disease.

Phase I study of 5-fluorouracil with folinic acid combined with recombinant human granulocyte-macrophage colony-stimulating factor.

A Phase I study was conducted to determine whether the addition of recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) to a combined 5-fluorouracil (5-FU) and folinic acid (FA) regimen would allow an escalated starting dose of 5-FU. FA (500 mg/m2) was administered as a 2-hour infusion on days 1 through 5, with 5-FU administered as a bolus injection 1 hour after the initiation of FA. Fifteen patients were enrolled in the trial; six were entered at a dose level of 375 mg/m2 of 5-FU, six at 450 mg/m2, and three at 540 mg/m2. rhGM-CSF was administered subcutaneously on days 6 through 15. A course of therapy was repeated every 28 days. Serious toxicity was observed at 450 mg/m2, with two patients developing grade 3 mucositis and one, grade 4 mucositis. Dose-limiting toxicity occurred at 540 mg/m2, at which point three patients developed grade 4 mucositis. One patient with metastatic colon cancer who received 5-FU at 540 mg/m2 achieved a partial response. Because of this persistent mucositis, the addition of rhGM-CSF used in this schedule would not allow an increased starting dose of 5-FU.

Acodazole hydrochloride: phase I trial, pharmacokinetics, and evaluation of cardiotoxicity in dogs.

Acodazole (NSC 305884) was examined in a Phase I trial evaluating a 1-h infusion repeated every 21 days in 37 patients with advanced carcinomas. Cardiac toxicity was dose-limiting at 1370 mg/m2, manifested as multiple premature ventricular contractions, QTc interval prolongation, and decreasing heart rate. Other toxicities included mild to moderate nausea and vomiting and local reaction near the i.v. injection site requiring the use of central venous catheters. Antineoplastic activity was not observed. Acodazole levels assayed by high-performance liquid chromatography disclosed a peak plasma level of 19 +/- 4 (SEM) micrograms/ml for 1370 mg/m2. Acodazole plasma levels decreased in a triphasic manner over a 100-fold range. The volume of distribution at steady state was 238 +/- 18 liter/m2 suggesting extensive tissue binding. The total body clearance was 13.6 +/- 0.9 liter/h/m2; the percentage of urinary excretion was 29 +/- 2% for 48 h. To evaluate cardiac toxicity, acodazole was administered to five dogs at 2262 mg/m2 (1-h infusion) which provided plasma concentrations similar to those achieved at 1370 mg/m2 in humans. Consistent findings in dogs were drug-related prolongation of QTc intervals, and reduction in heart rate, left ventricular dP/dt, and mean blood pressures. Clinical development of acodazole requires studies to further elucidate and alleviate this cardiac toxicity.

Phase I trial of spiromustine (NSC 172112) and evaluation of toxicity and schedule in a murine model.

Phase I evaluation of spiromustine was performed using an every-3-week schedule and a weekly X 3 schedule. Neurotoxicity was the dose-limiting toxicity presenting as alterations in cortical integrative functions (orientation, language, coordination), leading to a decrease in the level of consciousness. Traditional criteria for grading neurotoxicity poorly characterized these toxicities. The maximum tolerated dose was 6 mg/m2 every 3 weeks and 3 mg/m2 weekly X 3. Concurrent murine studies confirmed spiromustine as a schedule independent drug with toxicity correlating with peak plasma levels. Physostigmine had little effect on decreasing neurotoxicity in the murine model. The solvating agent used was not responsible for the neurotoxicity. Injection of spiromustine on a split-dose schedule decreased the acute neurological toxicity in mice and allowed a larger total dosage to be delivered (compared to single bolus dosage). Based on these results a split-dose schedule is suggested for future clinical trials.