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Because Cisplatin potentiates the effect of radiotherapy in animal tumor systems and because Cisplatin is capable of causing regressions of human malignant melanomas, a study was initiated in patients with malignant melanoma metastatic to brain to investigate the feasibility of administering Cisplatin once a week during cranial irradiation. Cisplatin 40 mg/m2/week (three doses) was given I.V. to 18 patients during whole brain irradiation, 3 000 rads in 12 fractions over 21/2 weeks. Eleven patients also received Cisplatin 120 mg/m2 every three weeks, starting three weeks after cranial irradiation. Median survival was ten weeks, and only one of 13 patients whose brain metastases had not been resected experienced neurological and CT scan improvement. Thirteen patients have died, and brain metastases were a major cause. No regression of extracerebral tumor was seen in 15 patients with evaluable extracerebral lesions. During weekly low-dose Cisplatin administration, nausea and vomiting were moderate to severe. No granulocytopenia was noted, although three courses were associated with mild thrombocytopenia. Mucositis, peri orbital swelling, vertigo, and headache were each noted in two of 51 courses of treatment and seizures, ototoxicity, pancreatitis, and hiccups were each noted in one course. Renal toxicity and ototoxicity each developed in three of the 11 patients receiving Cisplatin 120 mg/m2, and nausea and vomiting were severe.

Pentamethylmelamine (PMM) 80 mg/m2 was administered I.V. to 8 patients during surgical resection of intracerebral tumors. PMM concentrations in tumors were generally much higher than concurrent plasma concentrations, ranging from undetectable (less than .01 micrograms/g) to as high as 4.47 micrograms/g and were much higher in malignant melanoma samples than in astrocytoma samples. PMM was barely detectable or undetectable in most samples of edematous brain tissue adjacent to intracerebral tumor and in temporalis muscle. The PMM metabolites tetramethylmelamine (TeMM), trimethylmelamine (TrMM), and dimethylmelamine (DMM) were each detectable in tumor samples from one or two patients. Monomethylmelamine (MMM) was present in tumor samples from all except one patient. MMM was noted in samples of edematous brain tissue adjacent to tumor from 4 of 8 patients. It was the only PMM metabolite found in brain. TrMM, DMM, and MMM but not PMM, and TeMM were found in tumor cyst fluid from a patient with an intracerebral malignant melanoma. Two patients receiving therapeutic doses of PMM had biopsies taken of subcutaneous malignant melanoma deposits. PMM was undetectable in samples from one patient but reached high concentrations in the other patient. In both patients, MMM was the major metabolite. There was no indication that PMM penetrated into extracerebral tumors more readily than into intracerebral tumors Cerebrospinal fluid (CSF) samples were obtained from one patient without neurological toxicity who received low doses of PMM and from 4 patients receiving high doses of PMM who had developed neurological toxicity.(ABSTRACT TRUNCATED AT 250 WORDS)

[14C]AZQ (2–4 mg/m2, 100–200 mCi) was administered at varying times to five patients undergoing surgical resection of intracerebral tumors. Plasma, cerebrospinal fluid (CSF), edematous brain, and tumor specimens were obtained during surgery and the concentration of AZQ was determined radiochemically and chromatographically. Total [14C]AZQ equivalent concentration in tumor for two patients was determined to be 47.5% and 85% of concurrent plasma concentration which was similar to that found in normal brain (60.4% and 75.5% respectively). Only 18–45% of the total radioactivity in tumor tissue and 30–56% in plasma were accounted for by unchanged AZQ. These findings suggest that AZQ may be metabolized to a certain extent. Tissue samples from various organs were obtained during autopsy in a patient who expired ten days after AZQ administration. The highest AZQ concentration was found in the liver, followed by the kidney. Comparable amounts were found in normal brain and brain tumor (22 ng/ g vs. 31 ng/ g respectively). These results indicate that AZQ penetrates readily into the normal brain and brain tumor with a tendency to persist.

Forty-one patients with recurrent primary malignant brain tumors were treated with 2,5-diaziridinyl 3,6-bis (carboethoxyamino), 1,4-benzoquinone (AZQ) at an initial dose of 6–8 mg/m2/ day × 5 days. Courses were repeated monthly upon recovery of myelosuppression. Six of 25 evaluable patients (24%) showed definite tumor regression, and 7 (28%) showed disease stability as determined by monthly CT scans and neurologic examination. For all patients receiving one course of AZQ, the response rate was 16% (6 of 37 patients) and the stable disease rate 19%. The estimated median time to tumor progression with AZQ was 54 weeks for the responding patients and 36 weeks for the stable patients. Toxicity consisted of myelosuppression, primarily thrombocytopenia, which was delayed and cumulative. Other toxicities were uncommon. Further clinical trials in patients with malignant primary brain tumors, including combination studies with other drugs, are indicated.

Uptake of vinblastine into human cerebrospinal fluid, intracerebral tumor and autopsy tissues was quantitated radiochemically after separating vinblastine from its metabolites by high pressure liquid chromatography. Only low concentrations of vinblastine were found in cerebrospinal fluid from a single patient. A second patient who received a tracer dose of radiolabelled vinblastine prior to surgical resection of an intracerebral tumor had slightly less radioactivity in tumor than in temporalis muscle, but more in tumor than in edematous brain surrounding the tumor. The radioactivity in tumor increased gradually and exceeded concurrent plasma radioactivity by 2 hr after drug administration. A third patient died 4 hr into a planned 24-hr infusion of radiolabeled vinblastine. Highest vinblastine concentrations were found in organs with high blood flow such as kidney and heart. Intermediate concentrations were found in liver and lung, and low concentrations were found in prostate, gastrointestinal tract, spleen, muscle, bladder, and hepatic and lymph node metastases. A fourth patient died one month after receiving radiolabeled vinblastine. Highest concentrations were in liver and next highest concentrations were in intracerebral tumor. Moderately high concentrations were found in pancreas, thyroid, lung, spleen, ovary, kidney, and kidney metastases. Lowest concentrations were found in omental metastases, heart, breast, and brain. Vinblastine concentration decreased with increasing distance into brain from the brain metastases. Thus, vinblastine was not selectively localized in tumors. The concentrations in tumor did not reflect the concentration in the organ in which the tumor was located. There was no indication that uptake into intracerebral tumor was impaired. Cerebrospinal fluid and brain concentrations of vinblastine did not give any indication of the concentration attainable in intracerebral tumor.

A pilot study was performed combining cis-diamminedichloroplatinum (CDDP) and radiation therapy to treat patients with high-grade astrocytomas. CDDP at a dose of 40 mg/ m2/ week intravenously was given during the course of cranial irradiation. Following irradiation, CDDP was given every three weeks on a schedule of 35–40 mg/ m2/ day for three days until toxicity became unacceptable or until tumor progression occurred. Radiation therapy consisted of 6 000 rads over a seven week period or 5 000 rads followed by an additional 1500 rads to the tumor site. Patients were followed by computerized axial tomography (CT) scan and neurologic examination. Thirty patients were entered onto the study; 22 were considered evaluable. The median survival was 53 weeks and the median time to progression was 21 weeks. Toxicity was generally tolerable; however, ototoxicity may be enhanced by this treatment. CDDP combined with cranial irradiation is tolerable and feasible, although close follow-up is recommended in case CDDP has to be temporarily interrupted.

Radiolabelled Baker's Antifolate (BAF) was administered to 6 patients undergoing surgical resection of intracerebral tumors. Levels of radioactivity in resected tumor and edematous brain adjacent to tumor were generally higher than levels in concurrent plasma samples and were generally comparable to levels in temporalis muscle. Levels in tumor cyst fluid were far lower than concurrent plasma levels and levels in surrounding tumor. Chromatography was performed on tumor from 2 patients and revealed that only a small proportion of the radioactivity represented unchanged BAF. The major metabolite present in tissues was 1 000 times less potent as an inhibitor of dihydrofolate reductase than was BAF. Five patients had cerebrospinal fluid (CSF) sampled following administration of tracer doses of radiolabelled BAF. Radioactivity levels were far lower in CSF than in plasma. Levels of radioactivity in the CSF were also far lower than levels in tumor and brain samples from other patients and were slightly lower than tumor cyst fluid levels. Two patients had CSF collected after they received therapeutic doses of BAF. In these patients, both CSF and plasma were assayed using a dihydrofolate reductase inhibition assay. As with tracer dose studies, CSF concentrations of BAF were substantially lower than were concurrent plasma concentrations. Thus it appears that only very low concentrations of BAF are attainable in human CSF and intracerebral tumor, although a metabolite which is a very weak inhibitor of dihydrofolate reductase attains high concentrations in tumor.

Eight patients were treated with leukocyte interferon for a variety of neurological malignancies that had failed or recurred after conventional therapy. Three patients with malignant astrocytoma received intratumoral interferon in dosages up to 9 million units 3×/ week, with total dosages of up to 160 million units. Interferon was administered intraventricularly in 4 patients with leptomeningeal metastases and one patient with multiple brain metastases. Dosages increased from 1 to 10 million units 3×/ week, and total dosages of up to 113 million units were given intraventricularly. Acute side effects of fever, nausea, vomiting, and headache occurred almost exclusively with intraventricular injections, and these subsided after the initial injection. Fatigue, loss of appetite, weight loss, and hematologic toxicity developed a few weeks after onset of treatment, independent of the dose given. A modest tumor regression was seen on CT scans of one patient with a malignant astrocytoma, who was treated with interferon for 8 months. In a114 patients with leptomeningeal metastases, the CS F became free of malignant cells for 6 to 10 weeks, while clinical improvement was less dramatic.

Generally tritiated homoharringtonine ([3H]HHT, 150 microCi, 430 micrograms) was administered intravenously to seven patients at varying times before surgical resection of malignant brain tumor. Plasma, urine, cerebrospinal fluid (CSF), and tumor specimens were obtained during surgery, and the concentrations of HHT, its major metabolite, and [3H]HHT equivalent were determined chromatographically and radiochemically. For [3H]HHT equivalent, the concentration in tumor ranged from 0.6 to 4.3 ng/g and the ratio of tumor to plasma concentration from 0.5 to 1.8. In one patient who had CSF available for drug determination, the CSF to plasma ratio of total [3H]HHT was 0.3 at 45 minutes after drug administration and less than 0.2 ng/ml was unchanged HHT. For unchanged HHT, drug concentration in tumor ranged from undetectable (4 patients) to 1.8 ng/g. A major metabolite of HHT was detectable in the tumor specimens of all the patients. These results indicate that homoharringtonine can penetrate into brain tumors; in 3 patients with brain tumors, the ratios of HHT concentration in the tumor to that in the concurrent plasma were greater than one.

Twenty-nine patients with recurrent primary malignant brain tumors were treated with 1-(2-chlorethyl)-3-(2,6-dioxo-3-piperidyl)-1-nitrosourea (PCNU) at an initial dose of 110 mg/m2 with subsequent doses determined by the degree of delayed toxicity. The interval between treatments was usually weeks. Eleven of 25 evaluable patients (44%) showed definite improvement and ten (40%) showed disease stability as determined by sequential CT scans and neurologic examination. The estimated median time to tumor progression for all 25 patients treated with PCNU was 28 weeks, 37 weeks for the responding patients but only 20 weeks for patients with stable disease. Toxicity consisted of delayed myelosuppression which was cumulative and occurred mainly with the platelets. Gastrointestinal toxicity occurred in a minority of the patients. PCNU has definite activity in primary malignant brain tumors which appears to be comparable to that reported for BCNU alone, but with less reported gastrointestinal side effects. Further clinical trials in patients with primary malignant brain tumors are indicated.