Therapy of advanced colorectal cancer with a combination of 5-fluorouracil, methyl-1,3-cis(2-chlorethyl)-1-nitrosourea, and vincristine.

In a randomized, controlled study of 80 patients with advanced colorectal carcinoma, the combination of 5-fluorouracil (5-FU), methyl-1, 3-cis(2-chlorethyl)-1-nitrosourea, and vincristine produced an overall degree to toxicity comparable to that of 5-FU used alone. At 10 weeks, a positive objective response rate of 43.5% was observed with the three-drug combination compared to 19.5% with 5-FU alone (P less than 0.5).

Phase I study of a five-day intermittent schedule for 1,2:5,6-dianhydrogalactitol (NSC-132313).

Because 1,2:5,6-dianhydrogalactitol (NSC-132313 (DAG; the main conversion reaction product of the treatment of dibromodulcitol by mild akali or human serum) showed considerable antitumor activity in various mouse and rat tumor systems, a phase I study in 50 patients was conducted with five daily iv treatments repeated every 6 weeks. Thrombocytopenia was the dose-limiting toxicity. At a dose of 40 mg/m2/day for 5 days, the median platelet nadir was 31,000/mm3 and occurred on day 20; the plate count returned to normal within 8 days. At the same dose, the median white blood cell (WBC) nadir was 2,300/mm3 also on day 20-, the WBC count returned to normal within 7 days. Anemia, nausea, and vomiting were usually mild to moderate. No renal, hepatic, central nervous system, cardiac, or pulmonary toxicity was identified. Antitumor effects of DAG were observed in patients with renal, bladder, and small-cell lung cancers. An iv dose of 20-30 mg/m2/day for 5 consecutive days, repeated every 5-6 weeks, was recommended for phase II studies.

Early clinical study of an intermittent schedule for maytansine (NSC-153858): brief communication.

Maytansine, an ansa macrolide, was evaluated in an early clinical trial in 40 adult patients with various solid tumors. Severe nausea and vomiting, sometimes associated with watery diarrhea and abdominal cramps, and liver function abnormalities, mainly elevation of serum glutamic--oxaloacetic transaminase levels, together constituted what we considered dose-limiting toxicity. Mild hematologic toxicity (mainly thrombocytopenia), neurotoxicity, and possibly cardiac toxicity were also noted. No antitumor effect was seen. An iv dose of 0.750 mg/m2 on days 1, 3, and 5 (total dose, 2.25 mg/m2) repeated every 4 weeks is recommended for Phase II trials.

Clinical studies of methanol extraction residue fraction of Bacillus Calmette-Guérin as an immunostimulant in patients with advanced cancer.

Forty patients with advanced gastrointestinal cancer, all previous chemotherapy failures, were treated with a methanol extraction residue of Bacillus Calmette-Guérin (MER) alone, administered intradermally in either weekly or every-4-week schedules. The only significant side effect was local cutaneous reaction ranging from papules through pustules to draining ulcerations. On the weekly schedule these reactions frequently reached a point of clinical intolerability. In spite of the advanced nature of their disease, 29% of the patients had increased reactivity to recall antigens; 57% showed an increased reaction to dinitrochlorobenzene challenge during MER therapy; 38% had significant increases in lymphocyte blastogenesis to phytohemagglutinin mitogen, 48% to concanavalin A, and 43% to pokeweed mitogen. Increases (greater than 25%) in immunoglobulins A, M, and G were also observed in 31, 41, and 28% of patients, respectively. MER therapy was associated with increased thymus-derived (T) and bone marrow-derived (B) cells and an increased ratio of T-cells to B-cells. Increases in those determinants reflecting cellular immunity (skin tests, phytohemagglutinin and concanavalin A blastogenesis, and T-cells) showed a positive correlation with patient survival. Increases in those determinants associated with humoral immunity (pokeweed mitogen blastogenesis, immunoglobulins, and B-cells) had, if anything, a negative survival correlation. In comparing administration schedules, the weekly method produced more frequent increases in dinitrochlorobenzene response, more rapid increases with higher peaks in lymphocyte blastogenesis transformation, and more frequent increases in circulating T- and B-cells. The every-4-week method was associated with significantly greater frequencies of increases in immunoglobulins A and M. Of 36 patients with measurable disease, 3 showed greater than 50% objective responses, 2 showed a 25 to 50% response, and 1 showed a mixed response. MER is a potent simulus to cellular and humoral immunity in the patient with advanced gastrointestinal cancer. This stimulation may occasionally result in a clinically evident antineoplastic effect.

Serum alpha-fetoprotein in patients with neoplasms of the gastrointestinal tract.

Serum alpha-fetoprotein levels were measured by a sensitive double-antibody radioimmunoassay in 580 patients with a variety of malignant and nonmalignant gastrointestinal diseases to determine the incidence of levels elevated above 40 ng/ml. Over 200 normal control subjects have all had levels below 40 ng/ml. Fifteen % of 95 patients with gastric carcinoma, 3 percent of 191 patients with colorectal carcinoma, 24 percent of 45 patients with pancreatic carcinoma, 25 percent of 8 patients with biliary tract carcinoma, and 70 percent of 73 patients with hepatocellular carcinoma had elevated serum alpha-fetoprotein. None of 14 patients with esophageal or small bowel carcinoma had elevated levels. In contrast, 1 percent of 154 patients with nonmalignant, nonhepatic gastrointestinal disease had elevations of serum alpha-fetoprotein. Alpha-Fetoprotein appears to be a potential marker for tumor activity in some patients with certain gastrointestinal cancers.

A comparative clinical and immunological assessment of methanol extraction residue of Bacillus Calmette-Guérin versus placebo in patients with advanced cancer.

Eighty-four patients with advanced cancer refractory to conventional therapeutic modalities were randomly assigned in double-blind fashion to one of three intradermal treatment regimens: "high"-dose methanol extraction residue fraction of Bacillus Calmette-Guérin (MER) (2.0 mg); "low"-dose MER (0.5 mg); or 0.9% NaCl solution placebo. Toxicity, consisting primarily of cutaneous inflammation and ulceration, was limited to patients receiving MER and was most severe with the high-dose regimen. Pretreatment clinical and immunological parameters were comparable between patient groups. Although a significant number of patients had increases in various immune parameters according to the criteria used, there was no appearent advantage to MER given in either dosage schedule compared to placebo. Patient survival was not affected by either MER regimen compared to placebo. This investigation failed to demonstrate any significant clinical or immunological benefit from MER given in two dosage regimens in patients with advanced cancer with the laboratory methodology used and emphasizes the importance of appropriate controls in evaluating immunostimulants in humans.

Phase I and clinical pharmacological evaluation of a parenteral hexamethylmelamine formulation.

Hexamethylmelamine has been evaluated in single agent and combination regimen studies for many years, but only following p.o. administration. Pharmacological studies in animals and humans have shown that systematic availability of parent drug following p.o. administration is relatively low and variable due to extensive first-pass metabolism rather than due to poor absorption. Two Phase I clinical trials, with accompanying pharmacokinetic studies, have been conducted by using a parenteral formulation in which hexamethylmelamine was prepared by Intralipid 10%. The parenteral formulation was well tolerated by all patients receiving hexamethylmelamine by 1-day and by daily for 5-days schedules. Nausea and vomiting were the dose-limiting toxicities. Maximally tolerated doses on the 1-day and daily for 5-days schedules were approximately 850 mg/m2 and 630 mg/m2/day, respectively. No responses were observed in either study. Following i.v. administration of 540 mg/m2 hexamethylmelamine, plasma elimination was best described by a three-compartment open model with terminal half-life, total body clearance, and steady-state volume of distribution values of 10.4 h, 0.75 liter/min/m2 and 460 liters/m2, respectively. Twenty-four h urinary recoveries of parent drug were less than 1% for all patients. Accumulation of hexamethylmelamine during the 5-day treatment at 945 mg/m2 suggested possible saturation of parent drug elimination at that dose. Phase II studies are currently under way with the parenteral formulation of hexamethylmelamine.

Phase I and clinical pharmacological evaluation of pirozantrone hydrochloride (oxantrazole).

Pirozantrone hydrochloride, an anthrapyrazole analogue, was selected for clinical evaluation based on broad antitumor activity against murine tumor systems and on potentially less cardiotoxicity when compared to anthracyclines. This anthrapyrazole analogue is currently under clinical evaluation, and we now report results on a Phase I clinical trial incorporating a pharmacologically guided dose-escalation scheme. Dose escalation was designed to proceed by factors of 2 until the patient drug exposure (concentration x time) was 40% of the murine exposure at the LD10 dose (90 mg/m2). Thereafter, more moderate dose escalations were employed. The target concentration x time value (59 micrograms-min/ml) derived from preclinical pharmacology data was exceeded in all three patients at a dose of 90 mg/m2. A dose of 160 mg/m2 was found to reproducibly result in appropriate myelosuppression. This dose is recommended for further testing in Phase II studies. Nonhematological toxicities encountered in this trial were mild, the most notable being phlebitis at the infusion site. Objective responses were observed in two patients, one with metastatic breast cancer and another with metastatic melanoma. Following a 60-min infusion, pirozantrone hydrochloride plasma elimination was monoexponential, with a half-life of approximately 30 min, mean total body clearance of 1.29 liters/min/m2, and mean steady state volume of distribution of 29 liters/m2.

Treatment of the carcinoid tumor and the malignant carcinoid syndrome.

Certainly in treatment of the carcinoid tumor surgery has a well-established curative and palliative potential. The primary challenge is a knowledgable marriage between stage of disease and aggressiveness of operative procedure. Nonsurgical treatment of the malignant disease per se has thus far not produced optimum results and, in the opinion of this author, should still be confined to a clinical research setting. It would seem very doubtful, however, that the more mundane types of trials, empirically testing drug after drug and arbitrarily concocted drug combinations, is the most productive road to follow. There is an evident need for more sophisticated approaches to this tumor, which has unique metabolic characteristics that should be pharmacologically exploitable. Past experience has indicated that such a setting may permit dramatic therapeutic accomplishment. There is a strong need for animal models or established cell lines which would facilitate preclinical therapeutic exploration. The carcinoid syndrome presents an unparalleled opportunity for fundamental physiologic observations and for experimental therapeutic study that can have applicability not only in palliating the syndrome itself but also in the management of other pathophysiologic states that may involve more subtle abnormalities of the same hormonal mechanisms. The patient with the carcinoid tumor should not just be a fascinating curio for grand rounds exhibition. He should be a focal point for research involving an experienced, multidisciplinary clinical team supported by devoted basic scientists. If our patient resources and efforts can be concentrated in this manner, the carcinoid should be a strong candidate for the next medically curable human cancer.

Therapy of metastatic carcinoid tumor and the malignant carcinoid syndrome with recombinant leukocyte A interferon.

Twenty-seven patients with metastatic carcinoid tumor, 24 of whom had the malignant carcinoid syndrome, were treated with recombinant leukocyte A interferon at a planned dose of 24 x 10(6) U/m2. Twenty percent of patients with measurable tumor experienced an objective regression and 39% of those with the carcinoid syndrome experienced a reduction of more than 50% in urine 5-hydroxyindoleacetic acid (5HIAA) excretion. Flushing was partially or completely relieved in 65% of patients and diarrhea was relieved in 33%. Regrettably, these favorable treatment effects were transient in nature, with objective regressions persisting for a median of only 7 weeks and hormonal responses for a median of only 4 weeks. Any therapeutic gain experienced by these patients seemed to be outweighed by the frequency and severity of toxic reactions, which consisted primarily of chills and fever, fatigue, anorexia, weight loss, leukopenia, and abnormalities of liver function. Whereas other interferons, administration by alternative dosages and regimens, or incorporation of interferons into drug combinations may merit future study, we cannot recommend recombinant leukocyte A interferon, administered by the methods we employed, for routine therapy of the carcinoid tumor or syndrome.

Hepatic toxicity associated with fluorouracil plus levamisole adjuvant therapy.

PURPOSE: To determine the frequency and nature of hepatic toxicity associated with fluorouracil (5-FU) plus levamisole adjuvant therapy. PATIENTS AND METHODS: All patients had resection of stage II or stage III colon cancer and were randomized to receive observation only, levamisole alone, or 5-FU plus levamisole. Serial liver function studies were documented in 1,025 patients who did not develop recurrence during the year of therapy. RESULTS: One hundred forty-nine (39.6%) of 376 patients treated with 5-FU plus levamisole showed laboratory abnormalities consistent with hepatic toxicity, compared with 16.3% of 251 patients treated with levamisole alone and 16.1% of 398 untreated controls. Most common was elevation of alkaline phosphatase, frequently accompanied by elevations of transaminase or serum bilirubin. Characteristically, these changes were mild, not associated with symptoms, and resolved when therapy was stopped. In some instances, they were associated with elevated carcinoembryonic antigen (CEA) tests or with fatty liver seen on computed tomographic (CT) scan or liver biopsy. CONCLUSION: Mild and reversible hepatotoxicity is a common consequence of 5-FU plus levamisole adjuvant therapy, but this is only rarely symptomatic. However, the oncologist should be alert to this phenomenon, since the associated laboratory and imaging findings may simulate those associated with hepatic metastasis.

A phase II study of combined 5-fluorouracil, doxorubicin, and cisplatin in the treatment of advanced upper gastrointestinal adenocarcinomas.

In a phase II study of 67 patients with upper gastrointestinal carcinomas and measurable disease without previous chemotherapy, we have evaluated the combination of intensive course 5-fluorouracil (5-FU) (300 mg/m2/d for five days) doxorubicin (40 mg/m2 on day 1), and cisplatin (60 mg/m2 on day 1). Courses were repeated every 5 weeks. Among 26 patients with gastric carcinoma, a 50% regression rate was obtained with a median survival for all patients of 9 months. Among 29 patients with pancreatic carcinoma, the regression rate was 21% and the median survival was 4 months. Regressions were also observed in smaller numbers of patients with carcinomas of the gallbladder and ampulla of Vater, as well as in cholangiocellular carcinoma of the liver. Toxic reactions were usually clinically tolerable and consisted primarily of nausea, vomiting, stomatitis, diarrhea, leukopenia, and alopecia. Phase III studies are in progress to place the value of this experimental regimen into clinical perspective.

Phase II clinical trial of triazinate in combination with mitomycin C for patients with advanced gastric cancer.

Thirty-three patients with advanced measurable gastric cancer were treated with a combination of mitomycin C and triazinate. Twenty-nine of these patients had failed prior chemotherapy. Nine patients (27%) had an objective tumor response (median duration, 10 weeks). Median survival of all patients treated was 21 weeks. This study demonstrates that carefully selected patients with advanced gastric cancer who have failed a trial of chemotherapy, but are still ambulatory and maintaining adequate nutrition are appropriate subjects for studies of new treatment regimens. Based on the observed objective tumor response rate and median patient survival, further studies of these drugs in combination for the treatment of advanced gastric cancer are indicated.

Streptozocin plus fluorouracil versus doxorubicin therapy for metastatic carcinoid tumor.

EST 5275 is a phase II and III study of fluorouracil plus streptozocin (5-FU plus STZ) or doxorubicin in patients with measurable progressive carcinoid tumor. Among one hundred seventy-two cases with no prior chemotherapy and no heart disease, the response rate was 22% for 5-FU plus STZ and 21% for doxorubicin, while the median response duration and median survival were 31 weeks and 64 weeks for the combination and 26 weeks and 48 weeks for doxorubicin. Thirty-three patients who failed 5-FU plus STZ crossed over to doxorubicin and achieved an 18% response. Of the thirty-five patients who failed on doxorubicin, 29% responded to 5-FU plus STZ. Hematologic toxicity was similar for both treatments; however, the 5-FU plus STZ patients experienced more vomiting but acceptable renal toxicity. Both chemotherapy regimens have antitumor activity in carcinoid tumors.

Treatment of locally unresectable cancer of the stomach and pancreas: a randomized comparison of 5-fluorouracil alone with radiation plus concurrent and maintenance 5-fluorouracil--an Eastern Cooperative Oncology Group study.

One hundred ninety-one patients with pathologically confirmed, locally unresectable adenocarcinoma of the stomach (57 patients) and pancreas (91 patients), were randomly allocated to therapy with 5-fluorouracil (5-FU) alone, 600 mg/m2 intravenously (IV) once weekly, or radiation therapy, 4,000 rad, plus adjuvant 5-FU, 600 mg/m2 IV, the first three days of radiotherapy, then follow-up maintenance 5-FU, 600 mg/m2, weekly. Forty-three patients (22%) could not be analyzed because of ineligibility or cancellation, thus 148 patients were evaluable. The median survival time was similar for both treatment programs and for both types of primary carcinoma, and was as follows: gastric primary carcinoma, 5-FU, 9.3 months; 5-FU plus radiotherapy, 8.2 months; pancreatic primary carcinoma, 5-FU, 8.2 months; 5-FU plus radiotherapy, 8.3 months. Substantially more toxicity was experienced by patients treated with the combined modality arm than by those patients receiving 5-FU alone. Severe or worse toxicity experienced by patients with gastric primary carcinoma treated by 5-FU was 19%, and the combined modality arm was 31%. The toxicity experienced by patients with pancreatic primary carcinoma treated with 5-FU was 27%, and the combined modality arm was 51%. Significant prognostic variables included: weight loss in stomach-cancer patients; and performance status, degree of anaplasia, and reduced appetite in pancreas-cancer patients.

Controlled evaluation of three drug combination regimens versus fluorouracil alone for the therapy of advanced gastric cancer. North Central Cancer Treatment Group.

PURPOSE: The purpose of this study was to evaluate the therapeutic effectiveness of fluorouracil (5-FU), doxorubicin, and methyl lomustine (CCNU) (FAMe), 5-FU, doxorubicin, and cisplatin (FAP), and FAMe alternating with triazinate (TZT) when compared with a standard therapy of 5-FU alone in patients with advanced gastric cancer. PATIENTS AND METHODS: Two hundred fifty-two eligible patients selected for study had proven locally unresectable and/or metastatic gastric adenocarcinoma. The majority had nonmeasureable disease. They were randomly assigned to receive one of the three drug combination regimens or to 5-FU alone administered by rapid injection in 5-day course. Survival was the primary study end point. RESULTS: None of the three drug combinations showed a significant advantage over 5-FU alone in improved performance score, weight gain, or patient survival. Each of the three combinations was more toxic than 5-FU alone. CONCLUSION: FAMe, FAP, or FAMe alternating with TZT cannot be recommended for the therapy of advanced gastric carcinoma. Therapy of this disease should remain an experimental endeavor. It would seem reasonable to prove the value of any new treatment approach by a randomized comparison to simple therapy with 5-FU alone.

Perioperative blood transfusions do not affect disease recurrence of patients undergoing curative resection of colorectal carcinoma: a Mayo/North Central Cancer Treatment Group study.

PURPOSE: To evaluate the effect of perioperative blood transfusions on colorectal cancer recurrence and patient survival. PATIENTS AND METHODS: A total of 1,051 patients treated with curative surgery for stage II or III colorectal adenocarcinoma were retrospectively studied for the effect of perioperative blood transfusions on disease recurrence and patient survival. Forty-two percent of patients received perioperative blood components. RESULTS: Perioperative transfusions had no effect on disease progression in univariate or multivariate analysis. Tumor stage (P = .0001), locally advanced tumor characteristics (adherence, involvement of adjacent structure, or perforation; P = .0001), location (rectal v colon; P = .0002), grade (P < .001), and cell kinetic profile (nondiploid or high percent synthetic phase [%S]+ percent gap 2 mitosis phase [%G2M]; P = .0003) were the most powerful independent predictors of tumor recurrence. Use of transfusions was associated with an adverse effect on overall survival (P < .004) using multivariate analysis, as well as tumor stage (P = .0001), location (P = .004), grade (P = .001), patient age (P = .0001), sex (P < .04), and cell kinetic profile (P = .0001). In further evaluation of the prognostic effects of transfusions, there was no increased risk of disease recurrence after whole-blood transfusion (P = .14) as compared with packed RBC or no transfusions, although the disease-specific survival for patients who received whole blood was lower than for nontransfused patients (P < .0005) patients who received other blood components (P < .03). CONCLUSION: With transfusion practices that use blood components, most commonly RBCs, medically indicated transfusions to patients with colorectal carcinoma seem to have no impact on disease recurrence. The adverse impact of transfusions on cancer patient survival is more likely due to other unevaluated tumor variables or underlying illness rather than tumor recurrence enhancement by immunosuppression induced by transfusion of blood components.

Clinical trial of sequential N-phosphonacetyl-L-aspartate, thymidine, and 5-fluorouracil in advanced colorectal carcinoma.

Preclinical studies have demonstrated enhanced cytotoxic effects of 5-fluorouracil (5-FU) when given in conjunction with N-phosphonacetyl-L-aspartate (PALA) or thymidine in several murine systems. Early clinical studies have demonstrated significant delayed depletion of pyrimidine nucleotides in tumor biopsy specimens following systemic PALA administration and prolonged serum levels of 5-FU after thymidine administration. Each of these biochemical effects would be anticipated to augment the cytotoxic activity of 5-FU. A phase II trial of a timed sequential administration schedule of PALA, thymidine, and 5-FU was conducted in 37 patients with advanced measurable colorectal cancer. Ten of 37 patients (27%) experienced objective tumor responses with a median response duration of 22 weeks, and 18 patients (49%) had stable disease for a median duration of 20 weeks. Six of 13 patients (46%) with anaplastic histology and/or rapidly progressive tumors experienced high-quality tumor responses. Leukopenia and neurologic side effects were the primary toxicities, including one death caused by sepsis. This regimen has demonstrated striking alteration in the 5-FU dose-effect relationship and definite antitumor activity in patients with advanced colorectal cancer. Further trials in patients with anaplastic carcinomas of the colon or other anatomic sites should be considered.

Combined 5-fluorouracil and radiation therapy as a surgical adjuvant for poor prognosis gastric carcinoma.

Sixty-two patients with resectable but poor-prognosis gastric carcinoma were randomized to either no surgical adjuvant therapy or treatment with 5-fluorouracil (15 mg/kg by rapid intravenous injection X 3) plus radiation (3,750 rad in 24 fractions) initiated 3 1/2 to six weeks postoperatively. Informed consent was obtained after randomization and only from the 39 randomized to treatment. Ten patients refused their treatment assignment. The five-year survival rate for patients randomized to treatment was 23%, and for those randomized to no treatment, 4% (P less than .05). Both the survival distributions and the alive-without-recurrence distributions were significantly different for the two groups (P = .024) and favored treatment assignment. When the treatment assignment group was broken down to those patients actually receiving treatment and those refusing, five-year survival rates were: treated, 20%; treatment refusal, 30%; controls, 4%; the three survival distributions were not significantly different. Thirty-nine percent of patients actually treated had a local-regional component of first clinical recurrence compared with 54% of those who received no treatment. This study does not establish 5-fluorouracil plus radiation as effective surgical adjuvant therapy for gastric cancer but suggests this approach as a possible fruitful area for continued research. This study also illustrates the potential problems that may be encountered in interpreting results when patients are randomized to a study before consent is obtained.

Early evaluation of combined fluorouracil and leucovorin as a radiation enhancer for locally unresectable, residual, or recurrent gastrointestinal carcinoma. The North Central Cancer Treatment Group.

PURPOSE: To develop a tolerable regimen of fluorouracil (5-FU), low-dose leucovorin, and radiation, and to obtain an early estimate of therapeutic effectiveness. PATIENTS AND METHODS: Forty patients with locally unresectable or recurrent gastrointestinal carcinoma were studied (pancreas, n = 22; rectum and sigmoid, n = 10; gastric, n = 6; other, n = 2). Irradiation therapy was administered in 1.8-Gy fractions 5 days per week, with total doses ranging from 45 to 54 Gy. 5-FU 400 mg/m2/d plus leucovorin 20 mg/m2/d, both by rapid intravenous injection, were administered for 3 or 4 days during the first and fifth weeks of radiation. 5-FU 425 mg/m2/d plus leucovorin 20 mg/m2/d were administered for 4 days at 4 weeks following radiation and for 5 days at 9 weeks. RESULTS: Major toxicities with upper abdominal treatment were nausea, vomiting, weight loss, and leukopenia. A tolerable dosage regimen was radiation at 45 Gy with 4 days of 5-FU plus leucovorin during the first week and 3 days during the last week with postradiation chemotherapy. Major toxicities with pelvic radiation were diarrhea and leukopenia. A tolerable regimen was 54 Gy with 4 days of 5-FU plus leucovorin during the first and fifth week followed by the postradiation chemotherapy. Median survival durations for pancreatic and rectal/sigmoid carcinomas are 13 months and 31 months, respectively. Five patients have no evidence of disease from 38 to 50 months after the onset of therapy (rectal, n = 2; stomach, n = 2; pancreas, n = 1). CONCLUSION: We have developed patient-tolerable regimens for combined 5-FU plus leucovorin followed by radiation to the abdomen and to the pelvis. The favorable results observed in locally unresectable disease allow cautious optimism for possible effectiveness in the surgical adjuvant setting, a possibility currently being tested in national trials of rectal and gastric carcinoma.