Treatment of carcinoma of the esophagus with 5-fluorouracil and recombinant alfa-2a-interferon

Pharmacotherapy for oesophagogastric cancer

Gastric cancer is the seventh and oesophageal cancer the ninth most common cancer in the UK, and >50% of patients present with locally advanced or metastatic disease. The incidence of oesophageal and oesophagogastric junctional tumours is increasing, making these important disease entities to understand and research. Despite improvements in surgical and peri-operative supportive care, 3-year overall survival with surgery alone for resectable disease is still poor. Outcomes in localised oesophageal cancer are improved with pre-operative chemotherapy, and in gastric cancer with peri-operative treatment or post-operative chemoradiotherapy. Oesophageal squamous cell carcinoma can be treated with definitive chemoradiotherapy as an alternative to surgery. While survival in patients presenting with metastatic disease is improved with the addition of systemic chemotherapy, median survival remains <1 year. Patients who are otherwise fit can be offered chemotherapy and this is superior to best supportive care. Regimens including a platinum and an anthracycline agent are favoured by the results of randomised trials. No standard second-line therapy has emerged. New research into taxanes has shown promising anti-cancer activity, and novel areas of investigation include incorporation of agents targeting vascular endothelial growth factor or epidermal growth factor receptor into standard regimens. This review focuses on the clinical trial evidence that dictates the optimal management of localised and advanced oesophagogastric cancer, focusing on pharmacotherapy. We examine areas of current research and highlight future therapeutic directions.

Multiple Management Modalities in Esophageal Cancer: Combined Modality Management Approaches

The overall success rate nationally in treating esophageal carcinomas remains poor, with over 90% of patients succumbing to the disease. In part I of this two-part series, we explored epidemiology, presentation and progression, work-up, and surgical approaches. In part II, we explore the promising suggestions of integrating chemotherapy and radiation therapy into the multimodal management of esophageal cancers. Alternative approaches to resection alone have been sought because of the overall poor survival rates of esophageal cancer patients, with failures occurring both local-regionally and distantly. Concomitant chemotherapy and radiation therapy (XRT) have been shown, by randomized trial, to be more effective than XRT alone in treating unresectable esophageal cancers and also have shown promise as a neoadjuvant treatment when combined with surgery in the multimodal treatment of this disease. Various studies have also addressed issues such as preoperative chemotherapy, radiation dose escalation, chemotherapy/XRT as a definitive treatment versus use as a surgical adjuvant, and alternative chemotherapy regimens. There are suggestions of some progress, but this remains a difficult problem area in which management is continuing to evolve.

Potential of interferon-alpha in solid tumours: part 2

The second part of this review examines the use of recombinant interferon-alpha (rIFNalpha) in the following solid tumours: superficial bladder cancer, Kaposi's sarcoma, head and neck cancer, gastrointestinal cancers, lung cancer, mesothelioma and ovarian, breast and cervical malignancies. In superficial bladder cancer, intravesical rIFNalpha has a promising role as second-line therapy in patients resistant or intolerant to intravesical bacille Calmette-Guérin (BCG). In HIV-associated Kaposi's sarcoma, rIFNalpha is active as monotherapy and in combination with antiretroviral agents, especially in patients with CD4 counts >200/mm(3), no prior opportunistic infections and nonvisceral disease. rIFNalpha has shown encouraging results when used in combination with retinoids in the chemoprevention of head and neck squamous cell cancers. It is effective in the chemoprevention of hepatocellular cancer in hepatitis C-seropositive patients. In neuroendocrine tumours, including carcinoid tumour, low-dosage (</=3 MU) or intermediate-dosage (5 to 10 MU) rIFNalpha is indicated as second-line treatment, either with octreotide or alone in patients resistant to somatostatin analogues. Intracavitary IFNalpha may be useful in malignant pleural effusions from mesothelioma. Similarly, intraperitoneal IFNalpha may have a role in the treatment of minimal residual disease in ovarian cancer. In breast cancer, the only possible role for IFNalpha appears to be intralesional administration for resistant disease. IFNalpha may have a role as a radiosensitising agent for the treatment of cervical cancer; however, this requires confirmation in randomised trials. On the basis of current evidence, the routine use of rIFNalpha is not recommended in the therapy of head and neck squamous cell cancers, upper gastrointestinal tract, colorectal and lung cancers, or mesothelioma. Pegylated IFNalpha (peginterferon-alpha) is an exciting development that offers theoretical advantages of increased efficacy, reduced toxicity and improved compliance. Further data from randomised studies in solid tumours are needed where rIFNalpha has activity, such as neuroendocrine tumours, minimal residual disease in ovarian cancer, and cervical cancer. A better understanding of the biological mechanisms that determine response to rIFNalpha is needed. Studies of IFNalpha-stimulated gene expression, which are now feasible, should help to identify molecular predictors of response and allow us to target therapy more selectively to patients with solid tumours responsive to IFNalpha.

Squamous cell carcinoma of the esophagus: a review and update

Squamous cell carcinoma (SCC) of the esophagus is an often-lethal disease that most commonly presents in an advanced stage with dysphagia in elderly patients. Known risk factors include alcohol and tobacco abuse, lye stricture, and achalasia. Screening protocols for high-risk patients are practiced in Japan but not in the United States. The diagnosis usually is made based on the results of esophagogastroduodenoscopy and contrast upper gastrointestinal radiographs. Staging is determined using computed tomography scanning and esophageal ultrasound, the latter rapidly being accepted as a superior method. Treatment is based on the stage of disease at presentation. Lesions without metastatic spread or mediastinal invasion generally should be treated with esophagectomy. Dysphagia associated with advanced lesions is difficult to treat, but may be palliated by surgery, radiation therapy, chemotherapy, laser ablation, peroral dilation, or esophageal stenting. Despite numerous medical advances, little headway has been made in managing and treating SCC, and a multidisciplinary approach is recommended.

A phase II trial of interferon-alpha and 5-fluorouracil in patients with advanced renal cell carcinoma. A Southwest Oncology Group study

BACKGROUND

Renal cell carcinoma is a common neoplasm that is often refractory to treatment. It is occasionally responsive to immunomodulating agents including interferon-alpha, which enhances the effects of 5-fluorouracil upon cells. Combinations of these two drugs have been most frequently tested in patients with gastrointestinal cancers, with some promising results. Because interferon-alpha has activity for renal cell carcinoma, a trial of this combination in patients with this malignancy was undertaken.

METHODS

The Southwest Oncology Group performed a Phase II clinical trial of the combination of 5-fluorouracil and interferon-alpha for recurrent or metastatic renal cell carcinoma. Eligibility criteria included no prior treatment with medications for cancer, a performance status of 2 or better, and bidimensionally measurable disease. The regimen studied consisted of 5-fluorouracil, 750 mg/M2/day, by continuous intravenous infusion on Days 1-5, and interferon-alpha-2b (Intron A), 5 x 10(6)U/M2/day, subcutaneously on Days 1, 3, and 5, repeated every 21 days.

RESULTS

Forty eligible patients were treated; twenty of the 40 underwent a nephrectomy. The regimen was tolerable: 3 patients had Grade 4, and 17 had Grade 3 toxicity. There were 5 partial responses (13% with 95% confidence limits of 4-27%). Median progression free survival for all 40 patients was 4 months and median overall survival was 15 months from the time of registration.

CONCLUSIONS

The combination of 5-fluorouracil and interferon-alpha given by this schedule, although tolerable and occasionally yielding responses, is not an improvement over existing therapies.

Phase II clinical trial with 5-fluorouracil, recombinant interferon-alpha-2b, and cisplatin for patients with metastatic or regionally advanced carcinoma of the esophagus

BACKGROUND

Recombinant interferon-alpha (IFN) augments the cytotoxicity of both 5-fluorouracil (5-FU) and cisplatin in vitro. A phase II study of 5-FU and IFN resulted in response rates of 25-27% in patients with metastatic esophageal carcinoma.

METHODS

A Phase II trial was initiated to determine the clinical utility of a three-drug combination (FIP) in patients with regionally advanced or metastatic esophageal carcinoma. Eligibility included biopsy-proven Stage III or IV squamous cell carcinoma or adenocarcinoma of the esophagus with no prior chemotherapy, adequate performance status, nutritional status, bone marrow, hepatic and renal function, and signed informed consent. Patients were treated in the exact sequence of IFN==>cisplatin==>5-FU. Patients received 5-FU, 750 mg/m2/day for 5 days followed by weekly bolus therapy at the same dose; cisplatin, 100 mg/m2 on Day 1, followed by weekly therapy, 25 mg/m2 over the course of 1 hour; and IFN, 10 MU subcutaneously 3 times/week beginning on Day 1. All patients received sargramostim (granulocyte-macrophage colony-stimulating factor, Escherichia coli-derived), 5 micrograms/kg subcutaneously 5 times/week. No patients received radiotherapy.

RESULTS

Twenty-four patients were enrolled; 23 were eligible, and 1 was excluded on pathology review (patient was found to have a leiomyoblastoma). The demographics of the population were: median age, 63 years (range, 43-73 years); 18 male patients; squamous cell carcinoma: adenocarcinoma ratio, 22:1, and Stage III:IV ratio, 10:13. Grade 3-4 National Cancer Institute Common Toxicity Criteria toxicities included: leukopenia (13), thrombocytopenia (14), and infection (9). Grade 3 diarrhea, mucositis, and vomiting occurred in 6 patients, 4 patients, and 1 patient, respectively. There were two instances of sudden death, likely related to tumor progression. Major responses occurred in 15 of 23 patients (65%; 95% confidence interval, 43%, 85%) (1 complete response, 14 partial responses). The median survival was 8.6 months; with a median follow-up of 26 months, estimated 30-month survival was 31%.

CONCLUSIONS

This regimen, although moderately toxic, has substantial activity in metastatic and regionally advanced squamous cell carcinoma of the esophagus. Further investigations should be conducted to determine the role of IFN in the treatment of esophageal carcinoma.

Phase I-II trial of recombinant interferon alpha-2b with cisplatin and 5-fluorouracil in recurrent and/or metastatic carcinoma of head and neck

The aims of this study were to establish the feasibility and toxicity of the biochemical modulation of the cisplatin (CDDP)-5FU combination by interferon alpha-2b (INF), and to assess its therapeutic efficacy in recurrent and/or metastatic squamous cell carcinoma of the head and neck (SCCHN). The mandatory eligibility criteria included histologically proven SCCHN; a performance status <2; adequate bone marrow, hepatic, renal, and cardiac functions; and measurable and/or evaluable disease. The protocol was CDDP, 100 mg/m2 i.v. day 1; 5-FU, 1,000 mg/m2 in a c.i.v. infusion over 96 h; and INF 3.10(6) U/day s.c., begun 2 h before cisplatinum for 5 consecutive days, repeated every 3 weeks. Twenty patients were included and received 76 cycles (median number cycles/patient = three). Eighteen patients were evaluable for activity with an overall response rate (RR) of 30% [2 complete responses (CR) + 4 partial responses (PR)], which was 55% (5/9) in previously untreated and 9% (1/11) in previously treated patients. Myelosuppression (50%), mucositis (40%), loss of electrolytes (15%), and asthenia (20%) were the most frequent severe toxic effects. Notwithstanding, the protocol was feasible and well tolerated in this overall population with a poor prognosis. Median duration of response was 8 months, and median survival for the overall population was 8.5 months. This schedule is the test arm of an ongoing international multicentric phase III trial versus standard CDDP-5FU in the same SCCHN population.

Weekly 5-fluorouracil and interferon-alfa-2b in metastatic cancer

Twenty-four patients with advanced cancer were treated with 5-Fluorouracil 600 mg/m2 intravenously and interferon-alfa-2b 3 MU subcutaneously both given weekly for 6 weeks followed by a 2-week hiatus. The median age of patients treated on this study was 66 years. Mild to moderate leukopenia, nausea/emesis, and anemia were the most common toxicities. There were no treatment-related deaths and only 1 episode of grade IV toxicity (leukopenia in a patient who was receiving concurrent radiation therapy). Two complete responses, 7 partial responses and 1 prolonged minor response (pancreas cancer--12+ months) have been seen. Weekly 5-FU and interferon is well-tolerated and shows activity in selected patients with advanced cancer.

Phase II trial of chemotherapy, external and intraluminal radiation plus surgery for oesophageal cancer

A pilot study was performed to assess the feasibility of combining 5-fluorouracil, recombinant alpha-2b-interferon, external radiation therapy and intraluminal high dose rate brachytherapy with surgery in patients with locally advanced esophageal carcinoma. 5-fluorouracil, 750 mg m-2, was administered via continuous 5-day infusion beginning day 1 and weekly thereafter; interferon, 10 mu subcutaneously, was administered three times per week beginning day 1 and sargramostin, 5 micrograms kg-1, was administered on days without 5-fluorouracil. External radiation began on day one using 1.5 daily fractions to 55.5 Gy. Intraluminal brachytherapy was delivered concomitantly once each week for 5 fractions of 4 Gy. None of the first eight patients went to surgery. The external radiation was changed to 1.5 Gy BID to 45 Gy followed by BID intraluminal radiation to 15 Gy. Of the last four patients, there was one case of radiation myelitis. It was found that successful surgery was not possible and excessive toxicities, including radiation myelitis, occurred with this aggressive regimen.

A phase II trial of interferon alpha-2A, 5-fluorouracil, and cisplatin in patients with advanced esophageal carcinoma

BACKGROUND

The combination of 5-fluorouracil (5-FU) and cisplatin has moderate antitumor activity in the treatment of metastatic epidermoid carcinoma of the esophagus. The authors have recently shown activity for the combination of 5-FU and interferon-alpha 2a (IFN-alpha) in both esophageal epidermoid and adenocarcinoma. A Phase II trial, therefore, was undertaken to evaluate the antitumor activity of the three-drug combination of IFN-alpha, 5-FU, and cisplatin in unresectable or metastatic esophageal carcinoma.

METHODS

Twenty-seven patients with locally advanced or metastatic carcinoma of the esophagus were treated. No prior chemotherapy was allowed. Twelve patients had epidermoid carcinoma (44%) and 15 patients had adenocarcinoma (56%). Patients received IFN-alpha at a dose of 3 x 10(6) units/day given daily by subcutaneous injection on days 1 to 28, 5-FU at a dose of 750 mg/m2/day for 5 days by continuous intravenous infusion on days 1 to 5, and cisplatin at a dose of 100 mg/m2 on day 1. Treatment was recycled every 28 days, and after the first three cycles, cisplatin was administered only on alternate cycles. Twenty-seven patients completed a median of 4 cycles (range, 1-13 cycles), and 26 patients were evaluable for response.

RESULTS

Major responses were observed in 13 patients (50%, 95% confidence intervals, 31-69%), including two complete responses (8%). The response proportion in epidermoid carcinoma (8 of 11 patients, 73%) was higher than the response proportion in adenocarcinoma (5 of 15 patients, 33%). The median duration of response was 29 weeks (range, 11-74 weeks), similar in epidermoid carcinoma and adenocarcinoma. Toxicity was moderately severe but manageable with dose attenuations. Grade 3/4 hematologic toxicity was observed in 41% of patients and grade 3/4 nonhematologic toxicity was observed in 26% of patients. IFN-alpha was reduced to either a 3- or 5-day a week schedule because of fatigue and/or myelosuppression in 12 patients (44%). There were two treatment-related deaths (7%).

CONCLUSION

In this Phase II trial, the combination of IFN-alpha, 5-FU, and cisplatin had substantial antitumor activity in esophageal carcinoma with apparently greater antitumor activity in epidermoid carcinoma than adenocarcinoma. A larger confirmatory trial comparing this treatment to conventional 5-FU and cisplatin is warranted for epidermoid carcinoma. In future chemotherapy trials, the response assessment for epidermoid and adenocarcinoma should continue to be stratified.

Interferon-alpha, 5-FU and prednisone in metastatic renal cell carcinoma: a phase II study

BACKGROUND

Due to the possibility of a synergistic effect between Interferon (IFN-alpha) and 5-fluorouracil (5-FU), a phase II trial was conducted in metastatic renal cell carcinoma (MRCC) combining recombinant IFN-alpha, 5-FU and prednisone. Prednisone has been shown to decrease IFN-alpha-related toxicity without reducing the response rate.

PATIENTS AND METHODS

Thirty-one patients with measurable MRCC were entered into the trial; 16 of them had lung metastases only. In 26 patients (nos. 6-31) the following dose schedule was applied during an 8-week treatment cycle: IFN-alpha (Roferon, Roche, Basel, Switzerland): 12 x 10(6)U s.c. 3 times weekly; Days 1-5: 5-FU: 600 mg/m2/day continuous i.v. infusion; Weeks 3-8: 5-FU 600 mg/m2 x 1 weekly (bolus i.v.); prednisone: 10 mg x 2 per os daily for 2 weeks, and thereafter 5 mg x 2. In the first 5 patients higher doses of 5-FU led to unacceptable toxicity and subsequent dose alteration of the trial schedule. All 31 patients were evaluable for response. Seventy treatment cycles were given.

RESULTS

One complete and 6 partial responses were observed (response rate: 23%, 95% CI: 10%-41%), with a median response duration of 11 months. Except in one patient, hematological toxicity was confined to grades I and II. Eight patients developed grade III oral mucositis. Adverse cardiac events were observed in 3 patients. Dose modifications of 5-FU were necessary in 16 cycles. The IFN-alpha doses were transiently reduced during 8 cycles.

CONCLUSION

The assessed combination of IFN-alpha, 5-FU and prednisone is moderately active in MRCC, with response rates similar to those seen in patients on IFN-alpha monotherapy. The latter treatment approach seems preferable, as 5-FU-related toxicity (mucositis, cardiac toxicity) is averted.

Preclinical and clinical aspects of biomodulation of 5-fluorouracil

Although single agent 5-FU has for many years been the standard therapy for advanced colorectal malignancies, a number of recent clinical trials show higher response rates with biomodulation of 5-FU by several different agents. In general, trials of leucovorin, methotrexate, interferon, and PALA given in biomodulatory doses and sequences with 5-FU have demonstrated comparable response rates over a broad range. However, in the absence of controlled direct comparative phase III trials, final judgement on clinical superiority of a particular regimen must be reserved. Nevertheless, on the basis of current data, certain approaches appear promising and warrant further investigation. Compared to single agent 5-FU, survival benefit has been demonstrated with both low and high dose leucovorin/5-FU regimens and response rates in the 20-50% range appear reproducibly higher than those of 5-FU alone. Low dose and either continuous infusion or repetitive dosing of leucovorin, as well as the effect of treatment sequence and intervals between drugs, require additional investigation. When given 20-24 h before 5-FU, methotrexate achieves response rates similar to leucovorin modulated 5-FU, but the potential role of rescue leucovorin used in many of the trials makes definitive interpretation difficult. Interferon/5-FU regimens attaining response rates of 30-40% are promising but need to be carefully and rationally designed. Low dose PALA with effective doses of 5-FU achieving responses in 35-45% of patients represent a marked improvement in earlier trials of high dose PALA, but additional studies with higher doses not compromising 5-FU dose intensity should be considered. Certainly, the concomitant use of multiple modulating agents also needs further investigation. While many such trials already performed attained results no better than single agent biomodulation, the preliminary results obtained by Grem and colleagues with IFN/LV/5-FU in untreated patients, and by Conti et al. using TMTX/LV/5-FU in previously treated patients are encouraging. Further understanding of the mechanisms of action and interaction of modulating agents should allow additional rational combinations to be explored clinically. Cisplatin biomodulation of 5-FU has been studied in gastrointestinal and head and neck malignancies achieving excellent results in the latter group. Preclinical evidence exists which suggests, however, that 5-FU modulation of cisplatin may be more effective, especially when 5-FU is administered 24 h or more before cisplatin. Clinical investigation of this sequence is currently lacking. Data to support the clinical promise of AZT, IdUrd, uridine, and the benzylacyclouridines are not yet available, although preclinical and preliminary clinical studies are promising.

Combined treatment modalities in esophageal cancer. Should chemotherapy be included?

The poor prognosis of esophageal carcinoma patients after treatment with local modalities (surgery/radiotherapy) is well known. The purpose of this review is to assess the question whether addition of chemotherapy to local treatment of squamous cell carcinoma of the esophagus has had any beneficial effect on treatment results. In the absence of a sufficient number of randomized trials addressing this issue, data mainly from single-arm studies are discussed. Compiled data from studies on preoperative chemotherapy, preoperative chemoradiation and chemoradiation without surgery suggest that addition of chemotherapy to local treatment (surgery/radiotherapy) might increase short-term survival (2 years) compared to local therapy alone. In the case of chemoradiation without surgery this conclusion is strengthened by results from randomized trials. In general lack of long-term follow-up data limits conclusion whether to recommend the inclusion of chemotherapy into treatment of esophageal cancer or not. Treatment results, however, from studies utilizing combination chemotherapy given concomitant with radiotherapy support the contention that well-designed randomized trials with long-term follow-up should be performed. Outside controlled trials, however, surgery or radiotherapy should still be regarded as standard treatment modalities.

Biologic agents as biochemical modulators: pharmacologic basis for the interaction of cytotoxic chemotherapeutic drugs and interferon

Biochemical modulation of cytotoxic cancer chemotherapeutic agents is one means of enhancing the activity and selectivity of antitumor drugs. Traditionally this approach has utilized detailed information regarding a particular enzymatic reaction or biochemical pathway to develop potential modulating agents. In contrast, the reported clinical therapeutic activity of IFN in combination with cytotoxic agents has prompted a reexamination of the biochemical actions of the cytokine. Interferon elicits a number of cellular actions that might contribute to its pharmacologic activity, including both direct antitumor effects and host-mediated actions. The best understood are those related to the cytotoxicity of the fluoropyrimidine antimetabolites and include enzymatic reactions involved in fluoropyrimidine metabolic activation, catabolism, and interaction with its target enzyme. However, even in this instance, a mechanistic association of a specific pharmacologic action with therapeutic activity remains to be determined. These studies demonstrate that cytokines and other biologic agents may exert specific biochemical modulations that augment (or potentially attenuate) the activity of the cytotoxic chemotherapeutic agents.

Rolling review: gastrointestinal malignancy

The chemotherapy of gastrointestinal malignancies remain mostly investigational, although several adjuvant protocols in colorectal cancer and anal cancer are beginning to be accepted as standards against which newer regimens are to be compared. Chemotherapy regimens are best understood and appreciated with a basic understanding of cancer biology, tumour cell kinetics, and drug toxicities. An appreciation of chemotherapy-induced toxicity and an awareness of their management will help the gastroenterologist be an active participant in the multidisciplinary team caring for the patient with gastrointestinal malignancies.