A phase III randomized study of misonidazole plus radiation vs. radiation alone for cervix cancer.

BACKGROUND AND PURPOSE: A randomized-controlled study of radical radiotherapy for cervical cancer with or without the hypoxic sensitizer, misonidazole was conducted from 1981 to 1984 to investigate its therapeutic benefit. PATIENTS AND METHODS: Seventy-three patients were accrued from the Princess Margaret Hospital, and St John Regional Cancer Centre and randomized to either misonidazole (MISO, n = 39) or placebo (P, n = 34) in addition to radiotherapy. MISO was given orally each day 4 h prior to external beam radiation treatment (45Gy to midplane in 20 daily fractions) at a dose of 0.45 g/m(2), as well as during intra-uterine brachytherapy (40Gy). RESULTS: The 10-year overall survival (OS) for the entire group was 46%, and the disease-free survival (DFS) was 39%. The 10-year OS for patients in the MISO arm was 45%, compared to 49% for the P arm (P = 0.89). The corresponding DFS figures were 36 and 43%, respectively, (P = 0.6). Ten patients (14%) developed severe late complications (grade 3 or 4). The 10-year serious late complication rate was 14% for MISO and 12% for P (P = 0.51). CONCLUSIONS: Misonidazole failed to improve the outcome of patients with cervix cancer treated with radiotherapy.

Adverse effects at adjuvant treatment of liver metastases in rat with RSU-1069 + microspheres, or liposomal MTP-PE.

UNLABELLED: Rats were inoculated via the portal vein with a suspension of tumor cells from a transplantable dimethylhydrazine-induced adenocarcinoma of rat colon. In one set of experiments, the bioreductive drug RSU-1069 was injected once via the portal vein with or without degradable starch microspheres (DSM) 10 mins after tumour cell inoculation. In another set the immunostimulator liposomal-encapsulated muramyl tripeptide phosphatidyl-ethanolamine (MTP-PE) was injected via the portal vein or penile vein 1 day before tumour-cell inoculation and then twice a week. The experiments were finished after 2 to 3 weeks. Tumour take, numbers and volumes were measured. RESULTS: RSU-1069 enhanced tumour growth when combined with DSM. Liposomal MTP-PE also increased tumour growth. CONCLUSION: A bioreductive drug combined with microspheres, known to suppress the growth of an established tumour, may enhance its growth in the adjuvant setting. An accepted immunostimulator may enhance tumour take. Drugs used for the treatment of tumours must be carefully employed, if applied in an adjuvant setting. The effect on the normal immune system should be further studied.

The EORTC randomized trial on three fractions per day and misonidazole (trial no. 22811) in advanced head and neck cancer: long-term results and side effects.

From 1981 to 1984, a randomized study was done by the EORTC Radiotherapy Group comparing a fractionation schedule with three fractions per day (multiple fractions per day, MFD), with or without misonidazole, to conventional fractionation. The aim of the study was to obtain improved local and regional control and survival by shortening of the treatment time in the first 2 weeks of irradiation. Three fractions of 1.6 Gy/day (4-h interval) were given during 10 irradiation days to a total of 48 Gy. After 3-4-weeks interval, a boost was given to 67.2 or 72 Gy also in three fractions per day. This schedule was compared to an identical arm with misonidazole 1 g/m2/day and a third arm with conventional fractionation (70 Gy in 35 fractions, 7 weeks or 75 Gy in 44 fractions, 9 weeks). A total number of 523 patients was included in the study. Acute mucositis was much heavier in patients treated with three fractions per day (Van den Bogaert et al. Int. J. Radiat. Oncol. Biol. Phys. 8: 1649-1655, 1982). Early results, communicated in 1986 (Van den Bogaert et al. Int. J. Radiat. Oncol. Biol. Phys. 12: 587-591, 1986) showed no differences in treatment outcome between the three treatment arms. Long-term results and data on late effects are now available. Survival at 5 years was 18% (SE 1.9%) and locoregional control was 27% (SE 2.9%). No statistically significant differences could be observed between the three treatment arms.(ABSTRACT TRUNCATED AT 250 WORDS)

Hydroxyurea versus misonidazole with radiation in cervical carcinoma: long-term follow-up of a Gynecologic Oncology Group trial.

PURPOSE: Long-term follow-up data of a randomized trial that compared hydroxyurea and the hypoxic-cell radiosensitizer to misonidazole as adjuncts to standard radiation therapy in locally advanced carcinoma of the cervix are reported. PATIENTS AND METHODS: Three hundred eight women were entered, and all 294 eligible patients are assessable as randomized. Eighty-one percent of patients have been monitored for 5 years or to death. RESULTS: There was an advantage for hydroxyurea in progression-free interval and survival (P = .05 and P = .066, respectively). There was no significant difference in the distribution of sites of failure between the regimens. For the 39% of patients with stages III to IVA disease, the advantage in progression-free interval for hydroxyurea was significant (47.8% v 33.6%). More leukopenia occurred on the hydroxyurea regimen than on the misonidazole regimen. CONCLUSION: In summary, these data provide stronger evidence than our previous analysis that hydroxyurea is superior to misonidazole as an adjunct to radiation therapy. For patients with locally advanced carcinoma of the cervix, hydroxyurea continues to be the adjunct of choice with radiation.

Comparative study of thermoradiosensitization by misonidazole and metronidazole in vivo: antitumour effect and pharmacokinetics.

Tumour control by local hyperthermia (43.5 degrees C, 30 min) and radiation (20 Gy) given in combination with misonidazole (MISO) or metronidazole (METRO) was studied using FSa-II murine fibrosarcoma. When MISO or METRO (5 mmol/kg) was given 30 min before heat and subsequently treated with radiation, tumour regression was observed for both agents. Radiation dose-response curves for MISO and METRO with heating at 43.5 degrees C for 30 min were identical. Mouse foot reaction was used to evaluate local toxicity following combined heat, a nitroimidazole and radiation treatment. MISO enhanced the magnitude of foot reaction and prolonged the recovery time compared with heat plus radiation controls. There were no observable differences of foot reaction between animals treated with heat plus radiation and those animals treated with heat, radiation and METRO. Pharmacokinetics of the nitroimidazoles heated at 43.5 degrees C for 30 min in FSa-II tumours were investigated as a possible mechanism of thermal sensitization. Local hyperthermia did not alter the pharmacokinetics of METRO. Tumour concentration and tumour/plasma ratio of MISO were slightly decreased during heating. Since the hypoxic metabolism of the nitroimidazoles did not increase significantly during the heat treatment, the thermal enhancement of MISO or METRO radiosensitization cannot be explained by the increase in hypoxic cytotoxicity of the nitroimidazoles at elevated temperature alone. The two nitroimidazoles also were not accumulated in the tumour after heating. Therefore, alternation of pharmacokinetics is not the major mechanism for the thermal enhancement of nitroimidazole radiosensitization. The METRO radiosensitization effect became identical to that of MISO at elevated temperatures is of particular importance in clinical radiosensitization. The very low local and systemic toxicity together with the high efficacy of METRO at elevated temperatures will make it an attractive candidate as a future clinical radiosensitizer.

A randomized phase III protocol for the evaluation of misonidazole combined with radiation in the treatment of patients with brain metastases (RTOG-7916).

From 1979 through July 1983, 859 patients were enrolled in a Phase III RTOG Protocol (7916) evaluating the role of Misonidazole combined with radiation in the treatment of brain metastasis. Patients were randomized to one of four treatment arms (3.0 Gy x 10 fractions with or without 1 g/m2 of Misonidazole [total 10 g/m2] versus 5.0 Gy x 6 fractions with or without 2 g/m2 of Misonidazole) [total 12 g/m2]. Among the 779 analyzable cases, 63% had a lung primary and 12% had breast. Of the histologic types, 43% were adenocarcinoma and 24% were squamous cell. Seventy-eight percent had a Karnofsky of greater than 70. Of the 779 cases, 773 are dead (99%). Median survival is 3.9 months, with 60% alive at 3 months, 35% at 6 months, and 15% at 1 year. Survival was evaluated by treatment arm, Misonidazole status, and fractionation scheme; none showed any statistical significance. Favorable prognostic factors were assessed (age less than 60, Karnofsky of 70-100, controlled primary and brain metastasis only) in each treatment arm and no difference was found. Brain metastasis was cause of death in 1/3, and 19-33% of patients were retreated. Because up to 1/3 of the patients in this study died secondary to uncontrolled brain metastasis, improvement in local control remains an important goal. Until proven otherwise, the treatment of choice for the majority of patients still remains a conventional palliative course of 3.0 Gy x 10 fractions.

A phase I/II study of the hypoxic cell sensitizer misonidazole as an adjunct to high fractional dose radiotherapy in patients with unresectable squamous cell carcinoma of the head and neck: a RTOG randomized study (#79-04).

A randomized prospective trial was performed to study the toxicity and efficacy of the hypoxic cell sensitizer, misonidazole (MISO), used as an adjunct to high fractional dose radiotherapy in the management of unresectable Stage III and IV squamous cell carcinomas of the oral cavity, oropharynx and hypopharynx. From June 1979 to February 1983, 42 patients were randomized with 40 patients available for analysis. In the radiotherapy (RT) only group, 19 patients received a short course of high fractional dose radiotherapy with 400 rad per day, 5 days per week, to a total of 4400 to 5200 rad. In the radiotherapy plus misonidazole group (RT + MISO) 21 patients received the same radiotherapy plus 1.5 gm/m2 of misonidazole 3 times a week for a total of 7 doses. The observed side effects associated with misonidazole were: persistent numbness and paresthesia (1 patient), transient peripheral nerve paresis and persistent paresthesia (1 patient), and nausea and vomiting (2 patients). The treatment related morbidities were similar in both groups. Acute mucositis was seen in 4 of 19 patients in the RT group and 3 of 21 patients in the RT + MISO group. Acute airway obstruction requiring tracheotomy was seen in 2 patients with massive tumor in the base of tongue (1 in each group). Severe dysphagia requiring NG tube feeding was seen in 3 patients in the RT + MISO group and 3 patients in the RT group. The initial complete response rate in the RT group was 53%, versus 48% in the RT + MISO group. The estimated 2-year loco-regional control rates were 10% for RT alone and 17% for RT + MISO (no significancy). These results indicate that the addition of misonidazole does not improve the efficacy of high fractional dose radiotherapy for management of unresectable head and neck carcinomas. However, high fractional dose radiotherapy can be administered for the management of advanced head and neck carcinomas with acceptable morbidity and thus, is a useful regimen for future clinical trials of hyperbaric oxygen or new hypoxic cell sensitizers.

Misonidazole neuropathy. A prospective study.

The frequency with which polyneuropathy developed was investigated in patients with cancer of the larynx and pharynx who participated in a double-blind trial of the radiosensitizing drug misonidazole. Fourteen of 36 patients receiving misonidazole (total dose of about 11 g/m2) developed neuropathy, while this occurred in only 2 of 34 patients in the placebo group. Vibration perception threshold increased in all patients who developed neuropathy, but also in 12 (5 misonidazole and 7 placebo treated) without other symptoms or signs of neuropathy. Pharmacokinetic studies of misonidazole revealed a correlation between development of neuropathy and a high 'peak plasma concentration/g misonidazole in each fraction' and especially a high 'area under plasma concentration curve/g misonidazole in each fraction'.

A randomized trial of hydroxyurea versus misonidazole adjunct to radiation therapy in carcinoma of the cervix. A preliminary report of a Gynecologic Oncology Group study.

Between June 1981 and December 1985, 296 evaluable patients with carcinoma of the cervix (stages IIB, III, or IVA) were randomized to radiation therapy and either hydroxyurea (139 patients) or misonidazole (157 patients). All patients had undergone clinical, radiographic, and surgical staging. Patients with metastasis to periaortic nodes were ineligible for study. Patients received external radiation therapy to the pelvis and either one or two intracavitary applications. Hydroxyurea was given in a dose of 80 mg/kg each Monday and Thursday during external radiation therapy. Misonidazole was given in a dose of 1 gm/m2 in the same schedule, not to exceed 12 gm/m2. Of the evaluable patients, 60.8% had stage IIB disease and 33.8% had stage IIIB disease. Negative pelvic lymph nodes were found in 79.2% of the patients. Median age was 49 years (first and third quartiles 40 and 60, respectively). There were 51 patients who had severe and 15 patients who had life-threatening adverse effects (including two treatment-related deaths). As of February 1987 half the patients have either failed or been followed-up for at least 43 months. The group treated with hydroxyurea had a longer progression-free interval, bordering on statistical significance, than those treated with misonidazole (p = 0.08). The median progression-free interval for all patients randomized to hydroxyurea is 42.9 months and for misonidazole it is 40.4 months. The median progression-free interval for patients with stage III and IV disease who received hydroxyurea has not been reached and for the misonidazole group it was 10.1 months. There have been 120 recurrences, 51 (36.7%) in the hydroxyurea group and 69 (43.9%) in the misonidazole group; 51.7% of the recurrences have been limited to the pelvis or vagina. Failure limited to the pelvis occurred in 18.0% of patients receiving hydroxyurea and 23.6% of patients receiving misonidazole. There were 108 deaths, 47 (33.8%) in the hydroxyurea group and 61 (38.9%) in the misonidazole group; survival does not differ statistically between the two regimens at this point in follow-up (p = 0.25). Hydroxyurea has more short-term gastrointestinal and marrow toxicity, but is free of long-term neurotoxicity. Preliminary analyses indicate that there is no role for radiation therapy with misonidazole in cervical carcinoma.

Enhancement of the clinical activity of melphalan by the hypoxic cell sensitizer misonidazole.

One hundred patients with non-small cell lung cancer were entered by members of the Northern California Oncology Group into a randomized Phase II trial of i.v. melphalan versus i.v. melphalan with concomitant oral misonidazole. The patients had not received prior chemotherapy. Eighty-five patients were evaluable for assessment of response and 89 were evaluable for toxicity analysis. The melphalan/misonidazole group had a superior response rate (two complete and four partial responses among 42 patients or 14%) compared to the melphalan group in which there were no responses among 43 patients (p = 0.024, two-sided Fisher exact test). Since hematological toxicity was equivalent in the two groups, there was an improvement in therapeutic index. Data from 12 patients undergoing pharmacological studies demonstrated that the plasma concentration of melphalan was 25% higher in the misonidazole group, a difference that is not statistically significant. Although the mechanism of interaction has not been fully established, this randomized trial demonstrates that a chemosensitizer can enhance the clinical antitumor activity of an alkylating agent and suggests that chemosensitizers in combination with alkylating agents should be investigated in further clinical trials.

Palliation of advanced pelvic malignant disease with large fraction pelvic radiation and misonidazole: final report of RTOG phase I/II study.

Between October 1979 and June 1982 forty-six patients were entered on a non-randomized Phase I-II protocol for the evaluation of Misonidazole combined with high dose per fraction radiation for the treatment of advanced pelvic malignancies. Pelvic radiation consisted of 1000 cGy in one fraction repeated at 4-week intervals for a total of three treatments. Oral Misonidazole at a dose of 4 gm/m2 was administered 4-6 hr prior to radiation (total dose 12 g/m2). The distribution of histology consisted of 20 gynecologic, 24 bowel, and 2 prostate malignancies. Of the thirty-seven patients completing the three treatments; there were 6 complete responses (14% CR), 10 partial responses (27% PR) 19 minimal or no response (32% NR), and 4 unevaluable. One patient remains NED 5.5 years following radiation. Toxicity directly related to Misonidazole was minimal and consisted primarily of transcient Grade 1, 2 peripheral neuropathy (20% Grade 1, 4% Grade 2) and Grade 2 ototoxicity (4%). Radiation toxicity was significant for late bowel damage. There were 4 (11%) Grade 3 and 7 (19%) Grade 4 gastro-intestinal (GI) toxicities. Kaplan-Meier plot of GI toxicity showed a progressive increase in incidence with time for projected rate of 49% Grade 3, 4 by 12-month. GI toxicity (Grade 3, 4) was also related to tumor response. The complication rate was 80% (4/6) for CR, 30% (3/10) for PR and 26% (5/19) for NR or progression. Because of the GI complication rate, this protocol for palliation of advanced pelvic malignancies has been replaced by a protocol that uses 4 fractions over 2 days (b.i.d.) of 370 cGy per fraction repeated at 3-week intervals for a total of 3 courses.

Evaluation of CCNU and misonidazole in the treatment of advanced colorectal cancer.

Eighteen adult colorectal cancer patients, previously untreated with systemic chemotherapy, were given CCNU and MISO. One patient had an excellent partial response of pulmonary metastases, but the overall response rate was only 6%. Gastrointestinal toxicity was modest, hematologic toxicity was similar to what would have been predicted for CCNU alone, and there was no neurotoxicity detected. This Phase II study demonstrates that these two agents can be administered safely, but have no advantage over CCNU alone.

Misonidazole and CCNU chemotherapy for recurrent primary brain tumor.

CCNU chemotherapy prolongs survival of patients with primary brain tumor when given at the time of tumor progression following radiation therapy. Used as single agent, response rates of 30 to 80 per cent have been reported with median response durations of five to six months. Experimentally, tumor cytotoxicity is enhanced using the combination of misonidazole and CCNU, without increasing myelotoxicity. In this phase I/II study, 23 patients with primary brain tumor which progressed following radiation therapy were treated with combined CCNU and misonidazole. In all patients either the diagnosis of high grade glioma was made at the time of initial diagnosis prior to radiation therapy or the tumor transformed from low grade to high grade glioma at the time of progression following radiation therapy. CCNU 120 mg/M2 was given four hours following misonidazole 3.5 g/M2 every six weeks, with dosage adjustments for myelotoxicity. Treatment was continued for one year or until tumor progression. Of the 17 patients in the study for one year or more, 11 (65 per cent) survived for one year, and six (35 per cent) remained free of tumor progression for one year. Median time to tumor progression from start of CCNU plus misonidazole chemotherapy was 27 weeks and median survival was 80 weeks. No severe complications resulted from myelotoxicity. One patient developed mild peripheral neuropathy which disappeared following discontinuation of misonidazole.

Palliative topical and systemic misonidazole with low-dose irradiation for recurrent carcinoma of the cervix uteri.

This report concerns a determinate series of 11 patients with progressive recurrent cancer of the cervix uteri, who were treated with misonidazole (1 g) applied locally for 24 hours and an oral dose of 2.9 g/m2 four hours before a single mid-plane dose of 5.00 Gy. Four of 11 (36%) remained free of disease at one year. It is suggested that this is largely a hypoxic cell cytotoxic effect and is a useful method of palliation.

Postoperative radiotherapy of carcinoma in bilharzial bladder using a three-fractions per day regimen.

Patients with T3 bladder cancer who survived surgery and proved to have P3a, P3b or P4a tumors were randomized to either no further treatment (61 patients) or postoperative total pelvic irradiation (55 patients). A three-fraction per day regime was adopted with a dose per fraction of 125 cGy and an interval of 3 h between fractions. The total dose amounted to 3750 cGy divided into 30 fractions over 12 days. Patients of the postoperative radiotherapy group were re-randomized to radiotherapy alone or radiotherapy plus misonidazole (MISO) in a daily dose of 1 g/m2 given orally 2 h before the first daily fraction. The 2-year disease-free survival rate in the cystectomy alone group was 33 +/- 6% compared to 65 +/- 6% in the postoperative radiotherapy group. The therapeutic benefit applied to the two cell types, all histological grades and stages and to patients with or without nodal metastases. The benefit of postoperative irradiation was also verified by the Cox's multivariant analysis which adjusts for the relative representation of the important prognostic factors particularly pathological stage and nodal involvement. MISO did not seem to add to the therapeutic gain. No late complications were encountered in the wall of the rectum, small bowel or uretero-intestinal anastomotic sites. This is suggested to be due to the small dose per fraction used. However, early small bowel reactions were dose-limiting.

Effect of misonidazole dose on survival in patients with stage IIIB-IVA squamous cell carcinoma of the uterine cervix: an RTOG randomized trial.

Between August 1980 and November 1984, 120 patients with FIGO Stage IIIB or IVA squamous cell carcinoma of the uterine cervix were randomized to receive radiation therapy (RT) (46 Gy pelvis + 10 Gy parametrial boost) followed by intracavitary or external boost to the primary +/- misonidazole (MISO) (400 mg/M2 2-4 hours prior to RT daily, maximum 12 gm/M2). The median at 24-28 hr misonidazole plasma level was 20 micrograms/ml 2-6 hr and 3.5 micrograms/ml. Approximately 60% of the patients on RT + MISO received 100% of expected total Misonidazole dose; peripheral neurologic toxicity was reported for nine patients receiving misonidazole (8 with mild and 1 with moderate paresthesia or pain). Time-dependent regression analyses found that actual cumulative misonidazole dose was not related to duration of survival from start of treatment (p = 0.5). MISO dose expressed as a percent of expected dose was marginally related to increased survival measured from 14 weeks on on study (p = 0.1). No improvement in survival was observed with the addition of misonidazole to RT (64% of the patients on RT alone were alive at 18 months versus 54% of those on RT + MISO).

Radical irradiation and misonidazole in the treatment of advanced cervical carcinoma: results of a phase II trial.

Between February 1979 and January 1982, a Phase II study of misonidazole as a radiosensitizer was performed in 34 patients with advanced carcinoma of the uterine cervix. Twenty-nine patients were treated with conventional fractionated radiation and five patients with a twice daily fractionation schedule, 3 days a week. The total dose to the whole pelvis was 5000 cGy delivered in 5.5 weeks. Intracavitary curietherapy delivered an additional boost to the tumor. Misonidazole was given to all patients during external radiation and to 25 patients during intracavitary treatment for a total dose of 11 to 14 g/m2. All patients were followed for at least 28 months after treatment with a median follow-up of 52 months. Misonidazole toxicity included peripheral neuropathy (18%) and central nervous system toxicity (3%). The 3-year survival rate is 74% and the 3-year disease-free survival is 57%. When compared to our historical group survival, 42 and 12% for Stage III and IV, respectively, our data suggest that there is a probable advantage from using misonidazole in advanced carcinoma of the cervix.

Misonidazole and hemibody irradiation in the palliation of widespread metastases. Final report of an RTOG study.

The radiation therapy oncology group conducted a phase I/II trial of hemibody irradiation combined with high-dose misonidazole in the management of metastatic solid tumors. Thirty-seven patients received 39 hemibody irradiation treatments, each preceded by 4 g/m2 or 5 g/m2 misonidazole orally. One fraction of 600 cGy was delivered to a half-body volume. Objective tumor response occurred in 21% of evaluable patients, including one complete response. Pain relief was documented in only 36%. Acute toxicity consisting of nausea and vomiting was significant; 54% of patients experienced severe or very severe reactions. Other toxicities were acceptable. The low response rate and high acute toxicity contraindicate the use of misonidazole with hemibody irradiation for palliation.