Consensus guidelines from The American Society of Peritoneal Surface Malignancies on standardizing the delivery of hyperthermic intraperitoneal chemotherapy (HIPEC) in colorectal cancer patients in the United States.

BACKGROUND: The American Society of Peritoneal Surface Malignancies (ASPSM) is a consortium of cancer centers performing cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (HIPEC). This is a position paper from the ASPSM on the standardization of the delivery of HIPEC. METHODS: A survey was conducted of all cancer centers performing HIPEC in the United States. We attempted to obtain consensus by the modified method of Delphi on seven key HIPEC parameters: (1) method, (2) inflow temperature, (3) perfusate volume, (4) drug, (5) dosage, (6) timing of drug delivery, and (7) total perfusion time. Statistical analysis was performed using nonparametric tests. RESULTS: Response rates for ASPSM members (n = 45) and non-ASPSM members (n = 24) were 89 and 33 %, respectively. Of the responders from ASPSM members, 95 % agreed with implementing the proposal. Majority of the surgical oncologists favored the closed method of delivery with a standardized dual dose of mitomycin for a 90-min chemoperfusion for patients undergoing cytoreductive surgery for peritoneal carcinomatosis of colorectal origin. CONCLUSIONS: This recommendation on a standardized delivery of HIPEC in patients with colorectal cancer represents an important first step in enhancing research in this field. Studies directed at maximizing the efficacy of each of the seven key elements will need to follow.

Aberrant CpG-island methylation has non-random and tumour-type-specific patterns.

CpG islands frequently contain gene promoters or exons and are usually unmethylated in normal cells. Methylation of CpG islands is associated with delayed replication, condensed chromatin and inhibition of transcription initiation. The investigation of aberrant CpG-island methylation in human cancer has primarily taken a candidate gene approach, and has focused on less than 15 of the estimated 45,000 CpG islands in the genome. Here we report a global analysis of the methylation status of 1,184 unselected CpG islands in each of 98 primary human tumours using restriction landmark genomic scanning (RLGS). We estimate that an average of 600 CpG islands (range of 0 to 4,500) of the 45,000 in the genome were aberrantly methylated in the tumours, including early stage tumours. We identified patterns of CpG-island methylation that were shared within each tumour type, together with patterns and targets that displayed distinct tumour-type specificity. The expression of many of these genes was reactivated by experimental demethylation in cultured tumour cells. Thus, the methylation of particular subsets of CpG islands may have consequences for specific tumour types.

Concerted nonsyntenic allelic loss in human colorectal carcinoma.

Familial polyposis coli (FPC) is caused by an autosomal dominant gene on chromosome 5, and it has been proposed that colorectal cancer in the general population arises from loss or inactivation of the FPC gene, analogous to recessive tumor genes in retinoblastoma and Wilms' tumor. Since allelic loss can be erroneously scored in nonhomogeneous samples, tumor cell populations were first microdissected from 24 colorectal carcinomas, an additional nine cancers were engrafted in nude mice, and nuclei were flow-sorted from an additional two. Of 31 cancers informative for chromosome 5 markers, only 6 (19%) showed loss of heterozygosity of chromosome 5 alleles, compared to 19 of 34 (56%) on chromosome 17, and 17 of 33 (52%) on chromosome 18. Therefore, it appears that (i) FPC is a true dominant for adenomatosis but not a common recessive gene for colon cancer; and (ii) simple Mendelian models involving loss of alleles at a single locus may be inappropriate for understanding common human solid tumors.

Human villous adenomas engrafted into scid mice survive for prolonged period without malignant transformation.

Human villous adenomas are thought to represent premalignancies that subsequently give rise to colorectal adenocarcinomas. Currently there is no in vivo model in which to study the dedifferentiation and malignant transformation of these tumors. We establish here that human villous adenomas can be successfully engrafted into severe combined immunodeficient (scid) mice. Furthermore, these xenografts remain viable for up to 18 mo after either a subcutaneous or intraperitoneal inoculation of the human tissue. Tumors grew slowly and secreted a clear mucinous fluid. Examination of the tumors histologically at 1, 4, and 12 mo after implantation revealed that the villous polypoid structure was maintained and islands of atypical cells were observed within pockets of mucin surrounding the adenomatous tissue. No gross or histologic evidence of malignancy was detected throughout the 20-mo observation period. The human identity of the cells in the graft was confirmed by DNA in situ hybridization with a human-specific probe. We conclude that the human-scid xenograft described here represents a viable animal model with which to study the potential malignant dedifferentiation of villous adenomas over a prolonged period of time and to evaluate the possible contribution of selected oncogenic vectors on the malignant transformation of these adenomas.

p53 tumor suppressor gene status and the degree of genomic instability in sporadic colorectal cancers.

BACKGROUND: Genomic instability reflects the propensity and the susceptibility of the genome to acquire multiple alterations and, in turn, is believed to be a driving force behind multistep carcinogenesis. Although the molecular basis of genomic instability in sporadic colorectal cancers remains largely a mystery, mutation of the p53 tumor suppressor gene (also known as TP53) has been proposed to play an integral role in this process. However, a dilemma exists in that p53 mutation appears to be a late event in the progression of sporadic colorectal tumors, whereas genomic instability, serving as a facilitator of tumor progression, is envisioned as occurring early in this process. PURPOSE: We evaluated the relationship between p53 mutation and the major form of genomic instability in sporadic colorectal tumors, namely, that involving DNA breakage, which leads to chromosomal translocations, insertions, deletions, and gene amplification. METHODS: Fifty-eight sporadic colorectal tumors that had been previously evaluated for genomic instability were analyzed for p53 mutations. These tumors were from consecutively diagnosed patients. Genomic instability was quantified by use of inter-simple sequence repeat polymerase chain reaction analysis that employed (CA)8RG and (CA)8RY primers (R = purine [A or G]; Y = pyrimidine [C or T]); a genomic instability index (a measure of the number of alterations in tumor DNA in comparison with normal DNA, expressed as a percent) was calculated for each tumor. Mutation of the p53 gene in exons 5-9 was determined by use of single-strand conformational polymorphism-polymerase chain reaction analysis and DNA sequencing. Chi-squared analysis was used to determine the statistical significance of differences between groups of tumors. Reported P values are two-sided. RESULTS: p53 mutations were identified in 29 (50%) of the 58 tumors. The median genomic instability index value was 3.3%. Nineteen (65.5%) of the 29 tumors with p53 mutations had genomic instability indices that were less than the median value (range, 0%-2.6%); the remaining 10 (34.5%) tumors had genomic instability indices that were greater than the median (range, 3.9%-13.0%). Eleven (37.9%) of the 29 tumors with wild-type p53 genes had genomic instability indices that were less than the median value (range, 0%-2.6%), whereas the remaining 18 tumors had genomic instability indices above the median (range, 3.9%-11.7%). There was a statistically significant association between a lesser degree of genomic instability and the presence of p53 mutations (P = .032). CONCLUSIONS AND IMPLICATIONS: Tumors with no or minimal evidence of genomic instability are more likely to harbor p53 mutations than tumors with evidence of substantial genomic instability. p53 mutations play an important role in the development of cancers but do not appear to initiate or promote genomic instability in sporadic colorectal tumors.

Guidelines 2000 for colon and rectal cancer surgery.

BACKGROUND: Oncologic resection techniques affect outcome for colon cancer and rectal cancer, but standardized guidelines have not been adopted. The National Cancer Institute sponsored a panel of experts to systematically review current literature and to draft guidelines that provide uniform definitions, principles, and practices. METHODS: Methods were similar to those described by the American Society of Clinical Oncology in developing practice guidelines. Experts representing oncology and surgery met to review current literature on oncologic resection techniques for level of evidence (I-V, where I is the best evidence and V is the least compelling) and grade of recommendation (A-D, where A is based on the best evidence and D is based on the weakest evidence). Initial guidelines were drafted, reviewed, and accepted by consensus. RESULTS: For the following seven factors, the level of evidence was II, III, or IV, and the findings were generally consistent (grade B): anatomic definition of colon versus rectum, tumor-node-metastasis staging, radial margins, adjuvant R0 stage, inadvertent rectal perforation, distal and proximal rectal margins, and en bloc resection of adherent tumors. For another seven factors, the level of evidence was II, III, or IV, but findings were inconsistent (grade C): laparoscopic colectomy; colon lymphadenectomy; level of proximal vessel ligation, mesorectal excision, and extended lateral pelvic lymph node dissection (all three for rectal cancer); no-touch technique; and bowel washout. For the other four factors, there was little or no systematic empirical evidence (grade D): abdominal exploration, oophorectomy, extent of colon resection, and total length of rectum resected. CONCLUSIONS: The panel reports surgical guidelines and definitions based on the best available evidence. The availability of more standardized information in the future should allow for more grade A recommendations.

Randomized trial of postoperative adjuvant chemotherapy with or without radiotherapy for carcinoma of the rectum: National Surgical Adjuvant Breast and Bowel Project Protocol R-02.

BACKGROUND: The conviction that postoperative radiotherapy and chemotherapy represent an acceptable standard of care for patients with Dukes' B (stage II) and Dukes' C (stage III) carcinoma of the rectum evolved in the absence of data from clinical trials designed to determine whether the addition of radiotherapy results in improved disease-free survival and overall survival. This study was carried out to address this issue. An additional aim was to determine whether leucovorin (LV)-modulated 5-fluorouracil (5-FU) is superior to the combination of 5-FU, semustine, and vincristine (MOF) in men. PATIENTS AND METHODS: Eligible patients (n = 694) with Dukes' B or C carcinoma of the rectum were enrolled in National Surgical Adjuvant Breast and Bowel Project (NSABP) Protocol R-02 from September 1987 through December 1992 and were followed. They were randomly assigned to receive either postoperative adjuvant chemotherapy alone (n = 348) or chemotherapy with postoperative radiotherapy (n = 346). All female patients (n = 287) received 5-FU plus LV chemotherapy; male patients received either MOF (n = 207) or 5-FU plus LV (n = 200). Primary analyses were carried out by use of a stratified log-rank statistic; P values are two-sided. RESULTS: The average time on study for surviving patients is 93 months as of September 30, 1998. Postoperative radiotherapy resulted in no beneficial effect on disease-free survival (P =.90) or overall survival (P =.89), regardless of which chemotherapy was utilized, although it reduced the cumulative incidence of locoregional relapse from 13% to 8% at 5-year follow-up (P =.02). Male patients who received 5-FU plus LV demonstrated a statistically significant benefit in disease-free survival at 5 years compared with those who received MOF (55% versus 47%; P =.009) but not in 5-year overall survival (65% versus 62%; P =.17). CONCLUSIONS: The addition of postoperative radiation therapy to chemotherapy in Dukes' B and C rectal cancer did not alter the subsequent incidence of distant disease, although there was a reduction in locoregional relapse when compared with chemotherapy alone.

Expression of an unusual isozyme of lactate dehydrogenase in the serum of cancer patients and comparison with carcinoembryonic antigen.

Two studies reported here demonstrate a statistically significant association between metastatic cancer and the appearance of the k isozyme of lactate dehydrogenase in serum of affected patients. The first study included 190 coded samples from three types of cancer patients and matched controls; the second included 155 preoperative and 200 postoperative colorectal cancer patients. In the second, plasma carcinoembryonic antigen was compared with serum k isozyme of lactate dehydrogenase as an indicator of the presence of metastatic cancer. This comparison showed that both markers were independently useful for assessing patient status and predicted that a combination of the two should be a better discriminator for the presence of metastases than either marker alone.

Initial clinical (phase I) trial of TLC D-99 (doxorubicin encapsulated in liposomes).

A liposome-encapsulated form of doxorubicin (TLC D-99), which was shown in preclinical toxicology to be less toxic to the gastrointestinal tract and myocardium than free doxorubicin, was administered by constant infusion (1.00-1.80 h) to 38 patients in single doses of 20, 30, 45, 60, 75, and 90 mg/m2 every 3 weeks and daily for 3 days at doses of 20, 25, and 30 mg/m2/day. The dose-limiting toxicity was leucopenia: the maximum tolerated doses were one at 90 mg/m2 and three at 25 mg/m2/day. Nausea, vomiting, and stomatitis were minimal or absent at each dose; alopecia was minor. Fever and chills were noted at most of the doses, and malaise was seen in some patients, especially at the higher doses. No hepatic, renal, or other organ toxicities were observed. Clinical cardiac toxicity was not observed in any patient; however, the cumulative doxorubicin dose was greater than 400 mg/m2 in only one patient. There was large variation among patients in estimated pharmacokinetic parameters and profiles. Higher plasma levels and dose intensities were achieved with TLC D-99 than were predicted for free doxorubicin. Liposome-encapsulated doxorubicin was well tolerated and produced less nausea, vomiting, and stomatitis than would be expected with free doxorubicin administered at equally myelosuppressive doses.

An anoxia inducible endonuclease and enhanced DNA breakage as contributors to genomic instability in cancer.

Fischer rat embryo fibroblasts subjected to temporary anoxia followed by an aerobic recovery period show genomic instability in the form of highly elevated CAD gene amplification rates. As revealed by flow cytometric analysis this is associated with DNA breakage in vivo, followed by repair during the recovery period. Such genomic instability parallels expression of a M(r) 29,000/31,000 endonuclease; this enzyme requires no added divalent metal ion and has a pH optimum of about 6.5. The same endonuclease was found to be expressed within healing wounds and in four of ten human colorectal cancers but was not seen in eight normal colorectal tissue samples. Our results indicate that DNA breakage resulting from endogenous endonuclease activity can have a substantial effect in modulating genomic instability.

Enhanced levels of insulin-like growth factor messenger RNA in human colon carcinomas and liposarcomas.

The insulin-like growth factors I and II (IGF-I and -II) are proteins which stimulate cell proliferation and are important in normal human growth and development. They are coded for by separate genes and bind to specific cell surface receptors, eliciting a mitogenic response. IGFs are secreted by several cell lines derived from adult tumors. We have examined a number of human adult tumors for IGF messenger RNA (mRNA) expression and found IGF-II mRNA levels were consistently elevated in two types, colon carcinoma and liposarcoma. Adult colonic mucosa contains low levels of IGF-I and -II mRNA while several colon tumors, particularly of rectal and rectosigmoid origin, contained significantly elevated levels of IGF-II message. Over 90% of liposarcomas examined contained greatly elevated levels of IGF-II mRNA while control tissue (adipose) contained very low or undetectable IGF mRNA levels. Many of these tumors also contained elevated IGF-I mRNA levels. Northern analysis of these RNAs revealed differences in the abundance and sizes of IGF transcripts compared to other normal and malignant tissues known to express IGF.

Phase I-II trial of high-dose calcium leucovorin and 5-fluorouracil in advanced colorectal cancer.

Twenty-six patients with metastatic colorectal adenocarcinoma were entered into a Phase I-II study of 5-fluorouracil (5-FUra)-high-dose leucovorin (CF). The starting dose of 5-FUra was 300 mg/sq m with escalation to 750 mg/sq m/week in 6 doses given by rapid i.v. injection midway during a 2-hr infusion of CF, 500 mg/sq m. Partial responses were seen in 9 of 23 patients (6 of 12 who had had previous 5-FUra). Complete normalization of liver enzymes was seen in two of these patients. Side effects were seen sporadically with 5-FUra doses up to 600 mg/sq m. At a 600-mg/sq m 5-FUra dose, 8 of 18 patients had diarrhea, and 2 of 18 had white blood cell counts less than 3000/microliter. At a 750-mg/sq m dose of 5-FUra, 6 of 11 patients had severe diarrhea and 6 of 11 had white blood cell counts less than 3000/microliter. Other toxicities were mild conjunctivitis and lacrimation, thinning of the nails, and alopecia. In bioavailability studies of CF p.o., no plasma CF could be detected. After CF i.v., mean plasma peak was 111.3 +/- 40.3 (S.D.) microM. 5-FUra-CF appears to be effective in patients clinically resistant to 5-FUra. This study is being extended to randomized trial of 5-FUra-CF versus 5-FUra alone.

Genomic DNA-based hMSH2 and hMLH1 mutation screening in 32 Eastern United States hereditary nonpolyposis colorectal cancer pedigrees.

Hereditary nonpolyposis colorectal cancer (HNPCC) is an autosomal dominant cancer syndrome characterized by early age of onset colorectal cancer (mean 45 years) as well as endometrial, urinary tract, and upper gastrointestinal adenocarcinomas. The HNPCC phenotype has been shown to segregate with germline mutations in the human homologues of the DNA mismatch repair genes MSH2, MLH1, PMS1, and PMS2. However, the majority of published DNA mismatch repair gene mutation surveys associated with HNPCC kindreds report multiple levels of preselection, including 2p and 3p chromosomal linkage analysis and the evaluation of microsatellite instability of proband colorectal cancers prior to mutation analysis. For this reason, the concise contribution of each of the known DNA mismatch repair genes to the HNPCC phenotype remains unknown. We report the results of a genomic DNA-based analysis of hMSH2 and hMLH1 germline mutations in 32 unrelated Eastern United States HNPCC kindreds. These families were selected for study on the basis of phenotype only. We identified three hMSH2 and six hMLH1 mutations in eight families, for a positive mutation rate of 25%. Two mutations were identified in one of the families. Four of the mutations detected have not been reported in the literature previously. One of the mutation-positive families is African American; the others were of European-American ancestry. These results provide a clarification of the contribution of hMSH2 and hMLH1 to the HNPCC phenotype and suggest that in the majority of Eastern United States HNPCC kindreds selected by phenotype alone, the molecular genetic basis for the disease remains unknown.

Intrachromosomal genomic instability in human sporadic colorectal cancer measured by genome-wide allelotyping and inter-(simple sequence repeat) PCR.

We have used genome-wide allelotyping with 348 polymorphic autosomal markers spaced, on average, 10 cM apart to quantitate the extent of intrachromosomal instability in 59 human sporadic colorectal carcinomas. We have compared instability measured by this method with that measured by inter-(simple sequence repeat) PCR and microsatellite instability assays. Instability quantitated by fractional allelic loss rates was found to be independent of that detected by microsatellite instability analyses but was weakly associated with that measured by inter-(simple sequence repeat) PCR. A set of seven loci were identified that were most strongly associated with elevated rates of fractional allelic loss and/or inter-(simple sequence repeat) PCR instability; these seven loci were on chromosomes 3, 8, 11, 13, 14, 18, and 20. A lesser association was seen with two loci flanking p53 on chromosome 17. Coordinate loss patterns for these loci suggest that at least two separate sets of cooperating loci exist for intrachromosomal genomic instability in human colorectal cancer.

Phase II trial of fluorouracil and recombinant interferon alfa-2a in patients with advanced colorectal carcinoma: an Eastern Cooperative Oncology Group study.

In a pilot clinical trial, treatment of patients with advanced colorectal carcinoma with the combination of fluorouracil (5FU) and recombinant interferon alfa-2a (IFN) resulted in objective tumor regression in 62% of patients. To confirm these findings in a multiinstitutional setting, a phase II clinical trial was initiated by the Eastern Cooperative Oncology Group (ECOG) in 1989. The treatment regimen was identical to that used in the earlier study: 5FU 750 mg/m2/d for 5 days as a continuous infusion followed by weekly outpatient bolus therapy and IFN 9MU subcutaneously beginning day 1 and administered three times per week. Doses were modified for gastrointestinal, hematologic, and neurologic toxicity and for fatigue, similarly to those used in the previous pilot trial. Thirty-eight patients were registered; 36 are evaluable for response (one lost to follow-up and one with nonmeasurable disease). All patients had metastatic or locally recurrent disease beyond the scope of resection; 31 of 38 had liver metastases, and 20 of 38 had two or more sites of involvement. Eight patients had grade 4 toxicities, including sepsis (nonneutropenic) (one), watery diarrhea (two), and granulocytopenia (six). Grade 3 neurologic toxicities were observed in two (5%) patients and included slurred speech and gait disturbance. Objective response was 42% (95% confidence interval [Cl], 27% to 58%), including one clinical complete responder and 14 partial responders. Among the responding patients, the median time to treatment failure was 8 months. Two patients remain on treatment at 10+ and 16+ months: median survival has not been reached. The results of this multiinstitutional trial suggest that the addition of IFN to 5FU enhances the objective response rates achieved in patients with advanced colorectal carcinoma and that the toxicities of this regimen are acceptable.

A prospective evaluation of hepatic resection for colorectal carcinoma metastases to the liver: Gastrointestinal Tumor Study Group Protocol 6584.

We report here the results of the first multiinstitutional prospective evaluation of patients considered to have potentially resectable hepatic metastases from colorectal carcinoma. One hundred fifty-six patients were enrolled from 15 institutions. Six patients were subsequently excluded. One hundred fifty patients underwent surgery and are evaluable for analysis (median follow-up time, 3.1 years; range, 4 months to 5.1 years). Curative resection could be performed on 46% of patients (69 of 150), noncurative resection on 12% (18 of 150), while 42% were found to be unresectable (63 of 150). Thirty-day surgical mortality and morbidity rates in patients with attempted resection were 2.7% and 13%, respectively. The curative resection group was observed to have an improved median survival (37.1 months) compared with the noncurative resection group (21.2 months) and the unresectable group (16.5 months) (P less than .01). Computed tomographic (CT) scan was a poor predictor for resectability, and age was not a contraindication to curative resection. Preoperative carcinoembryonic antigen (CEA) values were also a poor predictor for resectability. However, the median CEA value 61 to 180 days postsurgery was significantly higher in unresectable patients compared with median CEA levels in noncuratively and curatively resected groups (P less than .01). Our results imply that curative resection leads to an increase in median survival. Noncurative resection provides no benefit to asymptomatic patients, since unresectable and noncurative resection groups have similar life expectancies. Longer follow-up will be needed to demonstrate the ultimate impact of curative resection on survival.

Plasma and tumor tissue pharmacology of high-dose intravenous leucovorin calcium in combination with fluorouracil in patients with advanced colorectal carcinoma.

Plasma pharmacokinetics of high-dose (500 mg/m2) leucovorin calcium (dl-5-formyltetrahydrofolic acid [dl-CF]) and fluorouracil (FUra) have been evaluated in patients with advanced colorectal cancer treated with the combination of FUra and dl-CF by two different intravenous (IV) schedules: (A) In patients with no prior chemotherapy, dl-CF was administered by a two-hour IV infusion and FUra by rapid IV injection one hour after the start of the dl-CF infusion and (B) in previously treated patients, dl-CF and FUra were administered by five-day continuous IV infusion (CI). Following the two-hour infusion of dl-CF, mean peak plasma concentration and elimination half-life of I-5-formyltetrahydrofolic acid (I-CF) were 24 +/- 6 mumol/L and 0.8 +/- 0.1 hour, respectively. CI of dl-CF over five days yielded a mean steady-state plasma level of I-CF of only 1.2 +/- 0.5 mumol/L. Peak and steady-state plasma concentrations of the metabolite 5-methyl tetrahydrofolic acid were comparable in the two schedules (17 +/- 8 mumol/L for the two-hour infusion and 12 +/- 5 mumol/L for the CI). Areas under the concentration v time curve (AUC) of total reduced folates were significantly greater under conditions of CI: 89.0 v 16.7 mmol/L/min for the two-hour infusion. In tumor tissue, 5,10-methylenetetrahydrofolate increased eight-fold two to four hours following the two-hour infusion and two-fold during the CI of dl-CF and FUra. Inhibition of thymidylate synthase (dTMP-S) by the two-hour and CI infusion schedules were 66% v 39%, respectively. The observed differences in the intracellular dTMP-S folate cofactor pools and the degree of inhibition of dTMP-S achieved in patients treated by two different schedules may be due to differences in the biochemical properties and/or to differences in the modulation of FUra metabolism by folate of tumor tissues obtained from newly diagnosed and previously treated patients.

A prospective randomized trial of 5-fluorouracil versus 5-fluorouracil and high-dose leucovorin versus 5-fluorouracil and methotrexate in previously untreated patients with advanced colorectal carcinoma.

Seventy-four previously untreated patients with metastatic colorectal adenocarcinoma were prospectively randomized into one of three treatment regimens: (1) 5-fluorouracil (5-FU) 450 mg/m2 as an intravenous (IV) bolus daily for five days or toxicity, then 200 mg/m2 IV bolus every other day for six doses; (2) methotrexate (MTX) 50 mg/m2 in normal saline by IV infusion over four hours followed by an IV bolus of 5-FU 600 mg/m2. This was administered weekly for 4 weeks and then every 2 weeks. (3) Leucovorin 500 mg/m2 in a two-hour IV infusion of normal saline with 5-FU 600 mg/m2 as an IV bolus one hour after the Leucovorin began every week for 6 weeks. The combined complete and partial response rates in the three regimens were 11%, 5%, and 48%, respectively (P = .0009). The median duration of response in the 5-FU and Leucovorin regimen was 10 months. There was no statistically significant difference between the treatment regimens with respect to survival time (P = .6). Toxicity in the 5-FU and Leucovorin regimen was predominantly diarrhea (13 of 30 patients, 40%). In this regimen, eight of 13 patients (52%) who developed diarrhea not only required a dose reduction of 5-FU, but also hospitalization for IV hydration. The predominant toxicity in the 5-FU alone regimen and the 5-FU and MTX regimen was leukopenia. One drug-related death occurred in each regimen.

Squamous cell carcinoma antigen as a marker for squamous cell carcinoma of the anal canal.

Twenty-one patients with documented squamous cell carcinoma (SCC) of the anal canal underwent prospective serial collection of 101 serum samples for radioimmunoassay of SCC antigen to evaluate regression or progression of disease. Eighteen presented with primary SCC of the anal canal, two with metastatic disease, and one with a recurrence in the perineum. Median follow-up was 18 months. Thirteen of 22 serum samples were true-positives, and nine of 22 were false-negatives. Four of 79 serum samples were false-positives and 75 of 79 were true-negatives. The sensitivity of this test is 59% and the specificity is 95%, with the accuracy of a positive test being 76%.

The benefit of leucovorin-modulated fluorouracil as postoperative adjuvant therapy for primary colon cancer: results from National Surgical Adjuvant Breast and Bowel Project protocol C-03.

PURPOSE: This study was designed to evaluate the efficacy of leucovorin-modulated fluorouracil (5-FU) as adjuvant therapy for patients with Dukes' stage B and C colon cancer. PATIENTS AND METHODS: Data are presented from 1,081 patients with Dukes' stage B and C carcinoma of the colon entered into National Surgical Adjuvant Breast and Bowel Project (NSABP) protocol C-03 between August 1987 and April 1989. Patients were randomly assigned to receive either lomustine (MeCCNU), vincristine, and 5-FU (MOF), or leucovorin-modulated 5-FU (LV + 5-FU). The mean time on study was 47.6 months. RESULTS: Comparison between the two groups indicates a disease-free survival advantage for patients treated with LV + 5-FU (P = .0004). The 3-year disease-free survival rate for patients in this group was 73% (95% confidence interval, 69% to 77%), compared with 64% (95% confidence interval, 60% to 68%) for patients receiving MOF. The corresponding percentage of patients surviving was 84% for those randomized to receive LV + 5-FU and 77% for the MOF-treated cohort (P = .003). At 3 years of follow-up, patients treated with postoperative LV + 5-FU had a 30% reduction in the risk of developing a treatment failure and a 32% reduction in mortality risk compared with similar patients treated with MOF. CONCLUSION: Treatment with LV + 5-FU significantly prolongs disease-free survival and results in a significant benefit relative to overall survival. These findings, when considered together with results from a recent meta-analysis demonstrating a benefit from LV + 5-FU in advanced disease, provide evidence to support the concept of metabolic modulation of 5-FU.