Sequential methotrexate/5-fluorouracil therapy with 5'-deoxy-5-fluorouridine against advanced gastric cancer: comparison between bolus injection and drip infusion of 5-fluorouracil administration. Hirosaki Cooperative Study Group for Cancer Chemotherapy

Forty-two patients with gastric cancer were entered in this study. Forty-one of them were eligible and administered sequential methotrexate (MTX)/5-fluorouracil (5-FU) with 5'-deoxy-5-fluorouridine (5'-DFUR). 5-FU was administered intravenously by drip infusion for 2 hours in 22 cases (group A), and was infused by bolus injection in 19 cases (group B). The treatment schedules were as follows: MTX 100 mg/m2 was given intravenously (i.v.) followed by 5-FU 600 mg/m2 i.v. 2 hours later and leucovorin 15 mg/body i.v. 8 and 20 hours later. This cycle was repeated once a week. 5'-DFUR 1,200 mg/body/day was given orally on 5 consecutive days per week. Three of 20 cases (15%) in group A showed PR, while 5 of 15 cases (33%) in group B showed PR. Median survival time was 2.8 months in group A and 3.7 months in group B. There was, however, no statistical difference. Gastrointestinal toxicity was commonly observed. Leukocytopenia was more severe in group B. Alopecia was more frequently observed in group B (p < 0.025). These results suggested bolus injection of 5-FU was a promising way of administration in sequential MTX/5-FU therapy.     

Arterial infusion chemotherapy of 5-FU and leucovorin for patients with liver metastases from colorectal cancer

Fifteen patients with liver metastases from colorectal cancer were treated by arterial infusion of 5-FU and leucovorin. Two regimens were performed. One was weekly bolus infusion of leucovorin following bolus infusion of 5-FU (bolus group), the other was 5 days continuous infusion of 5-FU and leucovorin in 3 weeks (continuous group). One PR was obtained both in the bolus group and in the continuous groups. The objective response rate was 11% in the bolus group and 20% in the continuous group. The one- and 2-year survival rates for these patients were 40% and 0% in the bolus group, and 80% and 60% in the continuous group, respectively. These results suggest that continuous arterial infusion of 5-FU and leucovorin was more effective than individual bolus arterial infusion of leucovorin and 5-FU for patients with liver metastases from colorectal cancer.     

A phase II study of 5-fluorouracil, leucovorin and cisplatin (FLP) for metastatic gastric cancer

The modulation of 5-fluorouracil (5-FU) with folinic acid (leucovorin, LV) is more efficacious than 5-FU alone in the treatment of metastatic colorectal cancer, and the combination of 5-FU with cisplatin is currently one of the most active regimens in advanced gastric cancer. A phase II study was therefore conducted to test the efficacy and toxicity of the combination of 5-FU, LV and cisplatin (FLP) in metastatic gastric cancer. 28 patients entered the study. Metastatic sites were observed in the liver (in 21 patients), the peritoneum (in 8), the lymph nodes (in 7) or the bones (in 1) and a local recurrence was noted in 4 cases. The performance status (using World Health Organisation criteria) was 0 for 13 patients and 1 or 2 for the others. Cycles of treatment were administered every 28 days and consisted of LV 200 mg/m2/day for 5 days followed by 5-FU 400 mg/m2/day for 5 days with cisplatin 100 mg/m2 on day 2. The response rate for the 27 evaluable patients was 51.8% (95% confidence interval (CI), 33-70.6%). There were four complete responses (14.8%) and 10 partial responses (37%). Median survival was 11 months and 4 patients were alive at 2 years. Both response rate and survival were better for patients with a good performance status. The overall toxicity was very low, except for 1 patient who died of dehydration and cardiac failure. In conclusion, the FLP protocol was effective and well tolerated in patients with metastatic gastric cancer.     

Oxaliplatin, folinic acid and 5-fluorouracil (folfox) in pretreated patients with metastatic advanced cancer. The GERCOD

Preliminary studies suggest synergy between oxaliplatin and fluorouracil (5-FU). To assess this issue, we performed a study in pretreated patients with advanced colorectal cancer (CRC) resistant to leucovorin and 5-FU. Regimen consisted of oxaliplatin day 1, 130 mg/m2 every two cycles (folfox 1) or 100 mg/m2/cycle (folfox 2) or 85 mg/m2/cycle (folfox 3) and leucovorin 500 mg/m2 as a 2-hour infusion, followed by 5-FU 22 h infusion 1.5-2 g/m2 for two consecutive days every 2 weeks. One hundred and thirteen patients have been treated. One complete response (CR) and 32 partial responses (PRs) were observed for an overall response rate of 29.2%. Sixty-seven patients had prior documented progression while receiving the same schedule of leucovorin and 5-FU than the one used in the folfox regimens, among them 18 had PRs (26.9%). The best response rate was observed in patients treated with the folfox 2 regimen: 41.7%. From start of folfox, median progression-free survival was 6 months and median survival 13 months. Limiting toxicities were peripheral neuropathy and neutropenia. Fifty-four percent of the patients experienced WHO toxicity > or = grade 3 with the folfox1 regimen, 45% with the folfox2 and 40% with the folfox3. The folfox regimens achieve a high response rate in pretreated patients with CRC. Further studies are needed to determine the best oxaliplatin dose-intensity.     

Paclitaxel with mitoxantrone, fluorouracil, and high-dose leucovorin in the treatment of metastatic breast cancer: a phase II trial

PURPOSE: Paclitaxel is a highly active single agent in the treatment of breast cancer. However, its optimal incorporation into combination regimens awaits definition. In this phase II study, we added paclitaxel, administered by 1-hour infusion, to a previously described combination regimen that included mitoxantrone, fluorouracil (5-FU), and high-dose leucovorin (NFL). PATIENTS AND METHODS: Forty-six patients with metastatic breast cancer received the following regimen as first- or second-line treatment: paclitaxel 135 mg/m2 by 1-hour intravenous (i.v.) infusion on day 1, mitoxantrone 10 mg/m2 by i.v. bolus on day 1, 5-FU 350 mg2/m by i.v. bolus on days 1, 2, and 3, and leucovorin 300 mg i.v. over 30 to 60 minutes immediately preceding 5-FU on days 1, 2, and 3. Courses were administered at 3-week intervals for a total of eight courses in responding patients. RESULTS: Twenty-three of 45 assessable patients (51%) had major responses. Previous chemotherapy, and in particular previous treatment with doxorubicin, did not affect response rate. The median response duration was 7.5 months. Myelosuppression was moderately severe, with 76% of courses resulting in grade 3 or 4 leukopenia. Hospitalization for treatment of fever during neutropenia was required in 13% of courses, and two patients died as a result of sepsis. Two patients developed severe congestive heart failure after a large cumulative anthracycline dose. CONCLUSION: This combination regimen was active as first- or second-line therapy for metastatic breast cancer, although its activity compared with other combination regimens or with paclitaxel alone is unclear. Myelosuppression was more severe than anticipated based on previous results with the NFL regimen or with paclitaxel administered at this dose and schedule as a single agent. The infrequent development of cardiotoxicity in these patients suggests that the paclitaxel/mitoxantrone combination may not share the problems previously reported with the paclitaxel/doxorubicin combination.     

5-fluorouracil and low-dose leucovorin as surgical adjuvant therapy from viewpoint of long-term outcome

Biochemical modulation of 5-FU by leucovorin (LV) has been demonstrated to increase the therapeutic effect compared to single agent 5-FU in the treatment of patients (pts) with advanced colorectal cancer. The purpose of this study was to determine the effectiveness of the 5-FU + LV combination as adjuvant therapy following surgery in pts with Dukes' B, C colon cancer. Pts were entered in a stratified clinical trial comparing two different combination chemotherapeutic regimens to single agent 5-FU, given orally as a control. This report summarized the result of treatment in 61 pts who were 5-FU oral alone and 32 pts who were 5-FU (375 mg/m2) and low-dose LV (20 mg/m2) intravenously for 5 days with 5-FU oral intake. 5-FU with LV regimen was associated with an improved survival compared with the single agent 5-FU oral intake (p < 0.05). 5-FU with LV regimen resulted in less recurrence in liver and lung compared with single-agent 5-FU oral intake.     

Two cases of advanced gastric cancer effectively treated with chemotherapy of 5-fluorouracil, cisplatin and cytarabine

We reported two cases of advanced gastric cancer effectively treated with chemotherapy of 5-fluorouracil (5-FU), cisplatin (CDDP) and cytarabine (Ara-C), 5-FU (300-350 mg/body) was given by continuous intravenous infusion. Ara-C (20-40 mg/body) by continuous infusion and CDDP (15-20 mg/body) were added intravenously for 3-6 days. For case 1, epirubicin (30 mg/body) was also given on the first day of each therapy course. Case 1 was a 62-year-old female who had gastric cancer with liver metastasis, ovarian metastasis and peritonitis carcinomatosa. After 3 courses of the chemotherapy, reduction of ovarian metastasis greater than 75% was observed. The value of CA125 decreased from 6,800 U/ml to 527 U/ml and ascites disappeared. Case 2 was a 54-year-old male who had type 3 advanced gastric cancer with multiple liver metastases. He received 6 courses of the therapy. Both primary and metastatic tumors showed over 50% reduction in tumor size. These suggested that this combination therapy was effective for inoperable advanced gastric cancers.     

Circadian chemotherapy in cancer patients

Continuous infusion of 5-FU at night was performed for four patients: three had liver metastasis (one with gastric cancer and two with rectal cancer) and one had local recurrence of rectal cancer. The chemotherapy schedule was 400 mg/m2/day 5-FU intraarterial or intravenous infusion from 6:00 p.m. to 6:00 a.m. for five days repeated every 3 weeks. There were one complete response, two partial responses and one with no change. It is expected that the chemotherapy of 5-FU at night will result in a high efficacy and lower toxicity.     

Is there a diagnostic role for bone scanning of patients with a high pretest probability for metastatic renal cell carcinoma?

A 66-year-old woman was admitted to our hospital complaining of abdominal pain and jaundice. Upper gastrointestinal series and computed tomography revealed pancreatic cancer. Pancreatectomy could not be performed because of portal invasion and multiple liver metastasis. Cholecystectomy, choledochojejunostomy and gastrojejunostomy were performed. The patient was treated with methotrexate (MTX) 100 mg/m2 i.v. followed one hour later with 5-fluorouracil (5-FU) 700 mg/m2. Leucovorin rescue of 10 mg po was given 24 hours after MTX administration. Treatment was repeated every 14 days. As a result, the size of a primary tumor of the pancreas was reduced (42%) on computed tomography, and the CEA level decreased to 27.8 ng/ml from 84 ng/ml. No side effects were observed. The patient continued to receive chemotherapy at our outpatient clinic for 20 months. She died of exacerbation of carcinomatous peritonitis 23 months after initial admission. Therefore, we conclude that MTX/5-FU sequential therapy seems beneficial to manage advanced pancreatic carcinoma from the viewpoint of antineoplastic activity as well as quality of life.     

In vitro percutaneous penetration through hairless rat skin: influence of temperature, vehicle and penetration enhancers

From February 1995 through October 1996, 25 patients with metastatic colorectal cancer showing a clinical resistance to 5-fluorouracil (5-FU) entered this study. Thirteen received oxaliplatin alone and 12 received it in combination with 5-FU. Oxaliplatin was administered at 130 mg/m2 over a 2-hour infusion every 3 weeks, alone or added either to 5-FU as a continuous infusion at 200 mg/m2 to 300 mg/m2 (six patients) or to a 5-FU bolus, 375 mg/m2, plus leucovorin, 100 mg/m2, daily for 5 days every 3 weeks (6 patients). Eighty-six of 98 administered cycles were evaluable for toxicity (47 for oxaliplatin plus 5-FU and 39 for oxaliplatin alone). Hematologic toxicity was mild, occurring as grade 2 leukopenia in 23% of the cycles of 5-FU and oxaliplatin and in 5% of the cycles of oxaliplatin alone. The most common toxicity was neurologic (grade 1 to 2 in 60%-6% of the cycles of the combination, respectively, and 68%-10% of oxaliplatin given alone) as hand-foot paresthesia or hypersensitivity to cold. No grade 4 toxicity was reported and only three patients in the 5-FU group developed grade 3 diarrhea. Grade 2 nausea and vomiting occurred in 33% of the cycles when both drugs were given and in 15% when oxaliplatin was administered alone. The combination of oxaliplatin and 5-FU induced four partial remissions (33%; 95% confidence interval, 6%-60%), whereas eight patients of the whole group had stable disease. No response occurred when oxaliplatin was administered as a single agent. The results of this study confirm the antitumor activity of oxaliplatin when added to 5-FU in patients who have metastatic colorectal cancer previously refractory to 5-FU. The possible therapeutic synergy with 5-FU was not accompanied by increased toxicity.     

A pilot study of gamma-1b-interferon in combination with fluorouracil, leucovorin, and alpha-2a-interferon

The combination of IFN-alpha-2a (IFN-alpha) and IFN-gamma-1b (IFN-gamma) has been found to produce more than additive cytotoxicity with fluorouracil (5-FU) in HT 29 colon cancer cells due to enhanced DNA-directed effects. We therefore studied the combination of IFN-gamma with IFN-alpha, 5-FU, and leucovorin (LV) in a clinical trial. Fifty-three patients received an initial cycle of 5 million units (MU)/m2 IFN-alpha s.c. on days 1-7 with 500 mg/m2 LV and 370 mg/m2 5-FU i.v. on days 2-6. IFN-gamma was then added once tolerable doses of 5-FU and IFN-alpha were established for each patient. IFN-gamma was administered at one of six dose levels between 0.3-4.8 MU/m2 s.c. on days 1-7. This design permitted comparison of the clinical toxicity and pharmacokinetics of 5-FU in two consecutive cycles in an individual treated with the same doses of 5-FU/LV/IFN-alpha in the absence and presence of IFN-gamma. In 43 matched patient cycles, the addition of IFN-gamma did not seem to worsen gastrointestinal toxicity, and skin toxicity tended to be milder. 5-FU clearance was higher in 14 cycles with IFN-gamma compared to the patient's prior cycle with the same doses of 5-FU/LV/IFN-alpha: 798 +/- 309 versus 601 +/- 250 ml/min/m2 (mean +/- SD; P = 0.04). In these 28 cycles, the median 5-FU clearance was significantly lower in 11 cycles that were complicated by more severe diarrhea: 524 versus 798 ml/min/m2 (grade 2 versus 0-1; P = 0. 0032). Overall, 38% and 26% of patients had grade 3-4 diarrhea and mucositis. Dose reductions of IFN-gamma for chronic fatigue, malaise, or anorexia were ultimately required more frequently with >/=2.4 MU/m2 (P = 0.018), and the maximum tolerated dose of IFN-gamma was considered to be 1.2 MU/m2/ day. Objective responses were seen in 41% of 29 measurable colorectal cancer patients. Compared to our previous experience with 5-FU/LV/IFN-alpha, IFN-gamma and IFN-alpha appeared to have opposite effects on 5-FU clearance. These results suggest that any potential benefit of adding IFN-alpha to 5-FU/LV on this schedule may not depend solely on alterations in 5-FU clearance.     

Long-term complete response in two cases of liver metastases from rectal and gastric cancer treated with intra-arterial infusion chemotherapy of leucovorin and 5-fluorouracil

Intra-arterial infusion chemotherapy combined with leucovorin (LV) and 5-fluorouracil (5-FU) was performed in two patients with multiple metastases from rectal and gastric cancer. In each patient LV 45 mg was infused as a bolus just before and after 5-FU 1,000 mg/4 hrs administration. Thereafter 5-FU dose was decreased gradually. This regimen was principally repeated weekly on an outpatient basis. In both patients PR was detectable 3 and 4 months after the beginning of chemotherapy, and CR was obtained in 21 and 6 months, respectively. Neither patient showed any signs of recurrence and are in good health 35 and 30 months after initiation of chemotherapy. These findings suggest that our protocol has an excellent anti-tumor effect and improves the QOL in some patients for a long time.     

Current status of low-dose CDDP. 5-FU therapy for solid malignant tumors--nationwide questionnaire survey

A nation-wide questionnaire survey was undertaken concerning low-dose anticancer therapy of CDDP plus 5-FU, which involves (5-10 mg CDDP/body/day + 300-500 mg/body/day) for 4-6 weeks. Out of 1,525 cases from 130 institutions, 847 cases with evaluable lesions were collected from 79 institutions. The response rate was 56.4% in esophageal cancer, 34.3% in gastric cancer, 35.3% in colorectal cancer, 47.2% in liver cancer and 35.9% in lung cancer, respectively. Adverse effects were found to be fewer and compliance was much better than the conventional therapy. Such figures suggest that the present regimen may be more effective than any so far. Problems for medical administration such as unlicensed CDDP for colorectal cancer were pointed out, which hinder the forthcoming third phase study.     

Cervical meningoceles and myelocystoceles: a unifying hypothesis

We initiated a pilot study of adjuvant hepatic arterial infusion chemotherapy (AHAIC) using 5-fluorouracil (5-FU) and leucovorin. Hepatic arterial infusion ports were placed in 15 consecutive patients undergoing curative resection of colorectal liver metastases. The chemotherapy regimen consisted of a weekly infusion of 5-FU (12 mg m 2 per day) and leucovorin (200 mg m 2 per day) for 12 months. The mean follow-up was 22 months (range 3-62 months, SD 21-37 months). There were no clinical or biological complications related to chemotherapy, except for sharp epigastric burns in four patients immediately after 5-FU infusions. Catheter irreversible occlusions led to early cessation of the treatment in three patients. Four of the 15 evaluable patients developed recurrent disease. The site of relapse was the liver in two patients and extra-hepatic sites in the two remaining patients. Three of these four patients died of their recurrent disease. These results suggest that 5-FU and leucovorin can be combined for AHAIC in a long duration regimen with a very low rate of side-effects. This protocol could be safely employed in a prospective randomized study in combination with 5-FU systemic infusions.     

Cardiovascular disease prevention in eastern Europe

A phase II trial was conducted to evaluate the efficacy and toxicity of a modulation of 5-fluorouracil (5-FU) by methotrexate (MTX) (with leucovorin (LV) rescue) as first-line chemotherapy in patients with locally advanced (inoperable) or metastatic gastric carcinoma. From July 1993 through August 1996, 36 patients with advanced gastric carcinoma received a regimen that consisted of: MTX 200 mg/m2 diluted in 250 ml normal saline by intravenous infusion over 20 minutes at hour 0; 5-FU 1,200 mg/m2 intravenous push injection at hour 20. Beginning 24 hours after MTX administration all patients received LV 15 mg/m2 intramuscularly every 6 hours for six doses. Cycles were repeated every 15 days. One patient was not assessable for response. Objective regression was observed in 15 of 37 patients (43%; 95% confidence interval, 26%-60%). One patient (3%) achieved complete response and 14 (40%) achieved partial response. No change was recorded in 14 patients (40%) and progressive disease was noted in six patients (17%). The median time to treatment failure was 7 months and the median survival was 12 months. Toxicity was within acceptable limits but one therapy-related death resulting from severe leukopenia occurred. The dose-limiting toxicity was mucositis. Five episodes of grade 3 or 4 stomatitis were observed and caused dosage modifications of MTX and 5-FU. Biochemical modulation of 5-FU by MTX appears as an attractive modality in patients with advanced gastric cancer. Further investigation both in experimental and clinical fields is needed to clearly define its role and to design the best modulatory strategy.     

Sequential intrahepatic fluorodeoxyuridine and systemic fluorouracil plus leucovorin for the treatment of metastatic colorectal cancer confined to the liver

PURPOSE: Extrahepatic metastasis represents a frequent pattern of disease progression when fluorodeoxyuridine (FUDR) is given by the intraarterial route for the treatment of unresectable colorectal liver metastases. Systemic fluorouracil (5-FU) plus leucovorin was added to intrahepatic FUDR to prolong the duration of disease control. METHODS: Only patients with colorectal cancer who had evidence of unresectable metastases confined to the liver were eligible. Laparotomy was performed to establish arterial perfusion of the liver. Cycles of intrahepatic FUDR followed by a 1-week rest period then intravenous chemotherapy with 5-FU plus leucovorin were administered until maximal regression of hepatic metastases. Maintenance chemotherapy with 5-FU plus leucovorin was then given until disease progression. RESULTS: Fifty-seven patients entered this trial; four patients (7%) were ineligible and 13 (23%) did not receive any chemotherapy on study because of findings at laparotomy. The 40 eligible patients who began chemotherapy are included in the statistical analyses. Twenty-five patients (62% of those who received chemotherapy) experienced regression of liver metastases. The median time to tumor progression was 9 months, but only 3% remained progression-free at 24 months. The median survival duration was 18 months. Toxicity was tolerable with no cases of biliary sclerosis. One treatment-related fatality due to sepsis was observed. CONCLUSION: Although short-term treatment results appear to be somewhat better than we have previously observed with intrahepatic FUDR alone, the sequential regimen did not have an impact on long-term, progression-free survival in patients with unresectable liver metastases. We are now investigating this regimen as surgical adjuvant therapy in selected patients following hepatic metastasectomy where this aggressive approach might have a greater therapeutic effect in the minimal residual disease setting.     

Hyperreactio luteinalis in a normal pregnancy: sonographic and MRI findings

We investigated the efficacy of combination chemo-therapy using 5-fluorouracil (5-FU), cisplatin (CDDP), and dipyridamole (DP), which is based on the concept of double biochemical modulation. Twenty-eight patients with advanced gastric cancer were treated with the simultaneous continuous intravenous (i.v.) infusion of 5-FU (800 mg/m2/day) and DP (4 mg/kg/day), and i.v. infusion of CDDP (20 mg/m2/day) for 5 days. The cycles were repeated every 4 weeks. Twelve patients (43%) had a partial response (PR), while stable disease (NC) occurred in 13 patients (46%), and progression (PD) in 3 patients (11%). An improved performance status was observed in 20 patients (71%). The carcinoembryonic antigen (CEA) level was markedly decreased in 75% of the CEA-positive patients. Toxicity was acceptable. The mean steady state plasma concentration of total DP was 6.40.5 microM, which thus seemed adequate to potentiate the cytotoxicity of 5-FU. The treatment regimen described herein thus appears to be effective, safe and well tolerated by patients with advanced gastric cancer.     

Changes in folate status as determined by reduction in total plasma homocysteine levels during leucovorin modulation of 5-fluorouracil therapy in cancer patients

We measured plasma total homocysteine (tHcy) in 14 patients (13 patients with colorectal cancer and 1 patient with breast cancer) during their first treatment with 5-fluorouracil (5-FU) plus leucovorin [LV (5-FULV)]. Eight of these patients were investigated a second time after 3-10 cycles (median, 4 cycles) with 5-FULV. Each cycle consisted of two administrations of 5-FU (500 mg/m2) and LV (60 mg/m2) given 24 h apart. The first administration of 5-FULV on day 1 of the first cycle induced a rapid reduction of the tHcy level from 12.5 micromol/liter (10.4-15.1 micromol/liter; geometric mean with 95% confidence interval of the mean) to 9.1 micromol/liter (7.5-11.1 micromol/liter) in 24 h. tHcy remained stable at this level after the second administration of 5-FULV. In addition, the 5-FULV regimen caused a concurrent 4-fold increase in both serum and erythrocyte folate. The fifth cycle with 5-FULV had only marginal effects on the tHcy level. 5-FU without LV modulation had no effect on the plasma tHcy or folate status in eight breast cancer patients. Our data establish the reduction of tHcy as a responsive indicator of LV pharmacodynamics.     

Adjuvant chemotherapy in colorectal cancer with high-dose leucovorin and fluorouracil: impact on disease-free survival and overall survival

PURPOSE: The rationale for using adjuvant chemotherapy in colorectal cancer is to achieve better disease control and thus reduce the high rates of tumor recurrence and mortality in patients who undergo curative surgery. The current literature, including relevant abstracts, on clinical trials of fluorouracil (5-FU) in combination with high-dose leucovorin as adjuvant chemotherapy for colorectal cancer is reviewed. The intent is not to present new data, but to present the reader with a broad perspective and larger patient experience on which to base well-reasoned treatment decisions. DESIGN: Published clinical trials and abstracts presented at the 1996 American Society of Clinical Oncology (ASCO) meeting that assessed 5-FU in combination with high-dose leucovorin as adjuvant chemotherapy for colorectal cancer were surveyed. End points of interest were disease-free survival (DFS), overall survival, and toxicity. RESULTS: In randomized trials that used high-dose leucovorin at doses that ranged from daily-times-five 200 mg/m2 to weekly 500 mg/m2 in combination with 5-FU, significant improvements in both DFS and overall survival were observed over surgery alone (control). In patients treated with high-dose leucovorin/5-FU, DFS rates ranged from 71% to 77% compared with control (58% to 64%). A similar trend was seen in overall survival, with a range of 75% to 84% compared with control (63% to 77%). Toxicities observed for high-dose leucovorin administered on a weekly or daily-times-five schedule were diarrhea, stomatitis, myelosuppression, and nausea. CONCLUSION: Overall, the results of these randomized trials support the use of high-dose leucovorin/5-FU as adjuvant therapy for colorectal cancer. Longer follow-up studies are needed to compare the benefits of these different regimens in terms of survival and to characterize adverse effects, especially those that may not be immediately evident. Adjuvant therapy with high-dose leucovorin/5-FU is an effective regimen that is well tolerated by many patients with colorectal cancer.     

Direction of predator approach and the decision to flee to a refuge

PURPOSE: We report the local control and survival of two Phase I dose escalation trials of combined preoperative 5-fluorouracil (5-FU), low-dose leucovorin (LV), and radiation therapy followed by postoperative LV/5-FU for the treatment of patients with locally advanced and unresectable rectal cancer. METHODS AND MATERIALS: A total of 36 patients (30 primary and 6 recurrent) received two monthly cycles of LV/5-FU (bolus daily x 5). Radiation therapy (50.40 Gy) began on day 1 in the 25 patients who received concurrent treatment and on day 8 in the 11 patients who received sequential treatment. Postoperatively, patients received a median of four monthly cycles of LV/5-FU. RESULTS: The resectability rate with negative margins was 97%. The complete response rate was 11% pathologic and 14% clinical for a total of 25%. The 4-year actuarial disease-free survival was 67% and the overall survival was 76%. The crude local failure rate was 14% and the 4-year actuarial local failure rate was 30%. Crude local failure was lower in the four patients who had a pathologic complete response (0%) compared with those who either did not have a pathologic complete response (16%) or who had a clinical complete response (20%). CONCLUSION: Our preliminary data with the low-dose LV regimen reveal encouraging downstaging, local control, and survival rates. Additional follow-up is needed to determine the 5-year results. The benefit of downstaging on local control is greatest in patients who achieve a pathologic complete response.