Faculty Bibliography

Carboplatin was given as a 30-min infusion to 11 ovarian cancer patients at doses of 170-500 mg/m2. The ages, weights, and creatinine clearances (Clcr) ranged from 44 to 75 years, from 44 to 74 kg, and from 32 to 101 ml/min, respectively. Plasma, plasma ultrafiltrate (PU), and urine samples were obtained at appropriate times for 96 h and were analyzed for platinum. The PU and urine were also analyzed for the parent compound by HPLC. In patients with a Clcr of about 60 ml/min or greater, carboplatin decayed biexponentially with a mean t1/2 alpha of 1.6 h and a t1/2 beta of 3.0 h. The mean (+/- SD) residence time, total body clearance, and apparent volume of distribution were 3.5 +/- 0.4 h, 4.4 +/- 0.85 l/h, and 16 +/- 3 l, respectively. Cmax and AUCinf values increased linearly with dose, and the latter values correlated better with the dose in mg than in mg/m2. No significant quantities of free, ultrafilterable, platinum-containing species other than the parent compound were found in plasma, but platinum from carboplatin became protein-bound and was slowly eliminated with a minimal t1/2 of 5 days. The major route of elimination was excretion via the kidneys. Patients with a Clcr of 60 ml/min or greater excreted 70% of the dose as the parent compound in the urine, with most of this occurring within 12-16 h. All of the platinum in 24-h urine was carboplatin, and only 2%-3% of the dosed platinum was excreted from 48 to 96 h. Patients with a Clcr of less than about 60 ml/min exhibited dose-disproportional increases in AUCinf and MRT values. The latter were inversely related to Clcr (r = -0.98). Over a dose range of 300-500 mg/m2, carboplatin exhibited linear, dose-independent pharmacokinetics in patients with a Clcr of about 60 ml/min or greater, but dose reductions are necessary for patients with mild renal failure

Between 1979 and 1984, 195 evaluable patients were entered in an international multicenter study comparing two regimens for patients with completely resected pathological Stage II testicular cancer (that is, with positive retroperitoneal lymph nodes). All patients had undergone orchiectomy and dissection of the retroperitoneal lymph nodes. They were randomly assigned to be treated with two cycles of immediate adjuvant cisplatin-based chemotherapy or to be observed monthly with treatment at relapse. The median follow-up period was four years. Of the 97 patients assigned to adjuvant chemotherapy, 6 (6 percent) had a recurrence; however, only 1 had received adjuvant chemotherapy before the recurrence. Three died (one of testicular cancer), and 94 of the 97 survived. Of the 98 patients who were observed, 48 (49 percent) had a relapse. However, almost all patients with relapses were effectively treated, and 93 of the 98 are alive and disease-free; 3 have died of testicular cancer. No identifiable factors were strongly associated with the risk of relapse. We conclude that two courses of cisplatin-based adjuvant chemotherapy will almost always prevent relapse in pathological Stage II testicular cancer treated with orchiectomy and retroperitoneal-lymph-node dissection. However, when surgery, follow-up, and chemotherapy are optimal, observation with chemotherapy only for relapse will lead to equivalent cure rates.

The three surgical steps in the management of carcinoma of the ovary--staging laparotomy, cytoreductive operation and second-look laparotomy--must be critically re-evaluated. During the past decade much data has been assembled on platinum based combination chemotherapy. The results of this type of chemotherapy questions the importance of these procedures. Whereas staging laparotomy will continue to determine important issues in the management of early disease, the use of cytoreduction and second-look laparotomy must be questioned as a routine or important determinant of current treatment results

We have employed a rationally designed combination attempting to biochemically modulate the cytotoxicity of methotrexate (MTX), an inhibitor of de novo purine and pyrimidine synthesis, by dipyridamole (DP), a noncytotoxic modulator which blocks cellular transport of preformed nucleosides, in the treatment of 27 patients with advanced colorectal carcinoma. Doses and schedule determined from a previous phase I pharmacokinetic study were MTX at 2.5 mg orally twice a day for 4 days to begin concurrently with DP, at 75 mg orally four times daily for 8 days. One partial response was achieved in a patient who had progressed on a previous regimen of leucovorin and 5-fluorouracil. The major toxic effects observed were myelosuppression and stomatitis. Lack of efficacy could be interpreted to reflect incomplete modulation. Therefore, studies employing continuous iv infusion of DP concurrent with or a loading schedule of DP prior to administration of MTX may be required to provide adequate evaluation of such biochemically directed strategies.

Fifty-two patients with advanced (stage III and IV) ovarian cancer were treated with a regimen of cisplatin (100 mg/m2 over 5 days) and cyclophosphamide (600 mg/m2/day 4). Treatment was repeated every 3-4 weeks for 6-8 months and followed by second look surgery. The median follow up for this single institution study (1980-1984) is 36 months. The median progression-free survival (projected) is 24 months and the median overall survival (projected) is 37 months in this group of patients with unfavorable pretreatment characteristics: median age: 61, median performance status (ECOG) 2, poorly-differentiated tumors: 60%, extensive residual tumors (greater than 2 cm): 65%. Pretreatment performance status was the only independent predictor for prolonged survival. Pathologically documented complete responses were observed in 23% of all patients and 43% of the patients who underwent second-look surgery (28 patients). Neurotoxicity from this regimen was substantial: it occurred in 65% of cases, was severe in 17% and was often not entirely reversible. The results with this intensive 2-drug cisplatin-containing regimen compare favorably to other more complex regimens in the literature. It is possible that the 'dose intensity' of cis-platinum may be the most important element of current therapeutic regimens in ovarian cancer