High-dose oral tamoxifen, a potential multidrug-resistance-reversal agent: phase I trial in combination with vinblastine.

BACKGROUND: P-glycoprotein mediates resistance to natural-product anti-neoplastic agents like vinblastine through an active transport process resulting in reduced intracellular concentration of these agents. The triphenylethylene antiestrogen tamoxifen and its major metabolite N-desmethyltamoxifen at concentrations of 4-6 microM enhance the intracellular concentration of natural-product antineoplastics and augment the cytotoxicity of such drugs three-fold to 10-fold in a variety of human and murine cell lines. PURPOSE: On the basis of these preclinical findings, we conducted a phase I clinical trial of high-dose, oral tamoxifen administered in conjunction with a 5-day continuous infusion of vinblastine. METHODS: We studied 53 patients with advanced epithelial tumors. Tamoxifen was given orally as a loading dose on day 1, followed by two doses a day on days 2-13. Vinblastine was given as a 120-hour continuous infusion (1.5 mg/m2 per day) on days 9-13 of each tamoxifen course. The starting dose of tamoxifen was 40 mg/m2 administered twice a day following a loading dose of 150 mg/m2. The maximum dose was 260 mg/m2 twice a day following a loading dose of 680 mg/m2. Treatment cycles were repeated every 28 days. RESULTS: The dose-limiting toxic effects of tamoxifen were neurologic and began within 3-5 days after the start of treatment. They consisted of tremor, hyperreflexia, dysmetria, unsteady gait, and dizziness. One patient experienced a grand mal seizure 24 hours after the last tamoxifen dose. Toxic effects were rapidly reversible. Asymptomatic prolongation of the QT interval on electrocardiogram occurred at doses of tamoxifen of 80 mg/m2 or higher given twice a day. No coagulation or ophthalmologic abnormalities occurred. Tamoxifen did not enhance the toxicity of vinblastine. Mean plasma concentrations of tamoxifen or N-desmethyltamoxifen at 260 mg/m2 tamoxifen given twice a day for 13 days were 6.04 and 6.56 microM, respectively. There was no relationship between plasma antiestrogen content and the development of neurotoxic effects. CONCLUSIONS: Tamoxifen at 150 mg/m2 given twice a day following a loading dose of 400 mg/m2 results in plasma levels of tamoxifen and N-desmethyltamoxifen of 4 and 6 microM, respectively, without dose-limiting toxicity. We recommend this dose for phase II trials of tamoxifen to modulate P-glycoprotein-mediated drug resistance. IMPLICATIONS: Our study demonstrates that high-dose tamoxifen can be safely administered and that plasma concentrations that may inhibit P-glycoprotein function can be achieved.

Enhancement of 1,25-dihydroxyvitamin D3-mediated antitumor activity with dexamethasone.

BACKGROUND: The active metabolite of vitamin D, i.e., 1,25-dihydroxycholecalciferol (1,25-D3), inhibits the growth of murine SCCVII/SF squamous cell carcinoma cells, both in vitro and in vivo. However, in vivo use of 1,25-D3 is hampered as a result of hypercalcemia (i.e., elevated levels of calcium in the blood). Glucocorticoids, such as dexamethasone, affect calcium absorption and modulate vitamin D receptor binding and have been used to treat hypercalcemia. In this study, we examined the effect of dexamethasone on tumor growth inhibition by 1,25-D3. METHODS: The effects of 1,25-D3 and dexamethasone, alone and in combination, on the growth of SCCVII/SF cells in in vitro culture or in vivo in female C3H/HeJ mice were determined by clonogenic tumor cell assay and/or by actual changes in tumor volume. Vitamin D receptor-ligand-binding activities in whole-cell extracts from cells (in culture), tumors, and normal tissues were assayed by single-point saturation analysis and equilibrium binding. RESULTS: Treatment of cultured SCCVII/SF cells with 500 nM dexamethasone for 24 hours before addition of 1,25-D3 reduced their survival. The growth of SCCVII/SF tumors was inhibited in mice treated simultaneously with dexamethasone and 1,25-D3 (as compared with no treatment or single-agent treatment); hypercalcemia was also reduced. Total vitamin D receptor content in SCCVII/SF cells was increased after treatment with dexamethasone. Treatment of tumor-bearing animals with dexamethasone (9 microg/day) for 7 days led to increased vitamin D receptor-ligand-binding activities in whole-cell extracts from tumor or kidneys and decreased activity in intestinal mucosa. CONCLUSIONS: Dexamethasone may enhance the antitumor effect of 1,25-D3 by increasing vitamin D receptor-ligand-binding activity.

Prognostic factors for survival in patients with recurrent or metastatic renal cell carcinoma.

A data base study of 610 patients with recurrent or metastatic renal cell carcinoma was conducted in order to identify clinical characteristics that are prognostic for survival in patients with this disease. Multivariate analysis identified initial Eastern Cooperative Oncology Group performance status (0 versus 1 versus 2 versus 3), time from initial diagnosis (greater than 1 year versus less than or equal to 1 year), number of metastatic sites (0,1 versus greater than 1), prior cytotoxic chemotherapy (no versus yes), and recent weight loss (no versus yes) as important indicators of survival. Closer examination of the resulting model indicated that patients can easily be separated into five prognostic subgroups, the subgroups being defined by a simple function of the number of risk factors present [Eastern Cooperative Oncology Group performance status 1, recent diagnosis (less than or equal to 1 year), greater than 1 metastatic site, recent weight loss, and prior cytotoxic chemotherapy each counting as a single risk factor; and Eastern Cooperative Oncology Group performance status 2 and 3 counting as 2 and 3 risk factors, respectively]. Median survival for each of the five risk groups was 12.8, 7.7, 5.3, 3.4, and 2.1 months, respectively.

Phase I clinical study with pharmacokinetic analysis of 2-beta-D-ribofuranosylthiazole-4-carboxamide (NSC 286193) administered as a five-day infusion.

A Phase I trial of 2-beta-D-ribofuranosylthiazole-4-carboxamide (NSC 286193, tiazofurin) was conducted using a 5-day continuous infusion schedule. Twenty-four patients with advanced cancer were entered on this trial. Dose levels ranged from 360 to 2350 mg/sq m/day for 5 days. Neurotoxicity was dose limiting and occurred in six patients. Neurotoxicity was expressed as confusion, lethargy, or obtundation and was associated with focal neurological deficits in four of six patients: hemiparesis, three; cortical blindness and bilateral upper extremity weakness, one. Neurotoxicity was not clearly dose related, occurring at 900 mg/sq m/day for 5 days (two patients), 1100 mg/sq m/day for 5 days (two patients), 1850 mg/sq m/day for 5 days, and 2350 mg/sq m/day for 5 days (one patient each). Other toxicities seen were myelosuppression, desquamation of palms and soles, malar erythema, and hyperpigmentation, stomatitis, chest pain, drug fever, and increased serum creatine phosphokinase. Administered drug [71.5 +/- 11.2% (SE)] was recovered intact in the urine within 24 h of administration. Terminal-phase mean harmonic half-life was 8.0 h. The unpredictable neurotoxicity seen following continuous infusion therapy with tiazofurin suggests that Phase II trials of this schedule are not indicated until better understanding of the biochemical effects of tiazofurin is achieved.

Clinical pharmacokinetics of cyclophosphamide and metabolites with and without SR-2508.

The pharmacokinetics of cyclophosphamide (CP) and several important metabolites was studied in detail in six patients receiving CP alone and with a radio- and chemosensitizing agent, SR-2508. CP at 1000 mg/m2 was either infused in 20 min alone or given 2 h before an infusion of SR-2508 at 5 g/m2 over 20 min, both separated by 3 weeks, to the same patients in a randomized fashion. Plasma and 24-h urinary levels of CP and four metabolites: [4-hydroxycyclophosphamide (4-OH CP), phosphoramide mustard (PM), chloroethyl oxazolidin-2-one, and alcophosphamide] were monitored by a gas chromatographic-mass spectrometric-stable isotope dilution assay. CP plasma levels were found to decline monoexponentially with the appearance of transient saturation kinetics in some and a mean t1/2 of 5.2 h for patients treated with CP alone. Plasma 4-OH CP levels showed a mean peak concentration of 2.4 microM and declined approximately in parallel to those of CP. The major circulating metabolite was found to be PM with a mean peak concentration of 40 microM and a terminal t1/2 of 15 h. The mean area under the plasma concentration curve (AUC) ratios between metabolites and CP were: 4-OH CP, 0.0158; PM, 0.4518; and chloroethyl oxazolidin-2-one, 0.179 with alcophosphamide at low levels. No appreciable amount of nornitrogen mustard was detected. Mean urinary excretion was: CP, 10.8; 4-OH, CP, 0.5; PM, 39.0; alcophosphamide, 0.4; and chloroethyl oxazolidin-2-one, 3.0, all expressed as a percentage of CP dose. No statistically significant difference was detected in all standard pharmacokinetic parameters determined for both CP and metabolites between patients with CP alone and with SR 2508. Plasma 4-(p-nitrobenzyl)pyridine activity was found to correlate the closest with PM profiles, with respect to both standard pharmacokinetic parameters and AUC values. When plasma PM AUC values were plotted against AUC values of circulating 4-(p-nitrobenzyl)pyridine activity, a correlation coefficient of 0.859 (P < 0.001) was obtained. Together with the significant cytotoxicity of PM these data support a significant contribution of circulating PM in the antitumor effect of PM.

Biochemical assessment of the effects of acivicin and dipyridamole given as a continuous 72-hour intravenous infusion.

Since this Phase I trial was based on a strategy of biochemical modulation, namely, the inhibition of nucleoside uptake by dipyridamole, a biochemical assessment of the actions of acivicin and dipyridamole was undertaken in order to aid our interpretation of the clinical findings. The primary biochemical objectives of this trial were: (a) to determine whether plasma levels of dipyridamole sufficient to inhibit nucleoside uptake could be achieved with a 72-h continuous i.v. infusion; (b) to monitor the effects of acivicin on two key enzymatic targets, CTP synthetase and GMP synthetase; and (c) to evaluate changes in cellular ribonucleoside triphosphate pools during therapy. Since peripheral blood mononuclear cells have relevant biochemical targets and can be serially obtained during the course of therapy, the biochemical effects of acivicin and dipyridamole were determined in these cells. At the maximally tolerated dose of dipyridamole (23.1 mg/kg/72 h), the steady-state concentrations of total and free dipyridamole averaged 11.9 microM and 27.8 nM, respectively. These levels were sufficient to inhibit cytidine (1 microM) uptake by greater than 50% in the lymphocytes of five of six patients so treated. Using lymphocytes obtained from 14 normal volunteers the concentration of free dipyridamole needed to inhibit the uptake of 1 microM cytidine by 50% averaged 13.8 +/- 1.1 nM. The plasma levels of alpha 1-acid glycoprotein, which tightly binds dipyridamole, ranged from 60 to 300 mg/dl in the patients in this study. As a consequence there were wide variations in the percentage of dipyridamole present as the unbound, pharmacologically active form and in the rates of dipyridamole clearance. The decreased rate of dipyridamole clearance seen in patients with high levels of alpha 1-acid glycoprotein resulted in higher plasma concentrations of total dipyridamole and compensated for the reduced fraction of free drug. Therefore, the plasma concentration of free dipyridamole varied much less than the total drug concentration in these patients. CTP synthetase and GMP synthetase activities were measured in patients' peripheral mononuclear cells prior to and at various times during therapy. CTP synthetase activity was inhibited in a time-dependent fashion by greater than 75% in seven of 13 evaluable courses; GMP synthetase was similarly inhibited in only three of ten cases. Ribonucleoside triphosphate pools were also measured in the patient's lymphocytes. CTP pool reductions of 30 to 50% were seen in nine of 19 courses, but in only four cases was the inhibition greater than 50%.(ABSTRACT TRUNCATED AT 400 WORDS)

Phase I clinical trial and pharmacokinetic evaluation of acodazole (NSC 305884), an imidazoquinoline derivative with electrophysiological effects on the heart.

Acodazole (NSC 305884) is a synthetic imidazoquinoline which has antimicrobial as well as antineoplastic properties. A Phase I trial of acodazole administered as a 1-h i.v. infusion once weekly X 4 was conducted. Mild to moderate nausea and vomiting and moderate burning and erythema at the infusion site were the only toxicities seen among 33 patients treated over 51 courses at doses between 20 mg/m2/week and 888 mg/m2. The first patient treated at 1184 mg/m2 developed an irregular pulse and was found to have a prolonged cardiac output interval (Q-Ti) on electrocardiogram and polymorphic ventricular tachycardia ("torsades des pointes"). Careful study of five additional patients treated according to a modified schedule (340 mg/m2 week one, 500 mg/m2 week 2, 666 mg/m2 week 3, and 888 mg/m2 week 4) revealed 20% or greater Q-Ti prolongation after 20 of 27 treatments; Q-Ti prolongation had resolved 24-36 h after each infusion. Q-Ti prolongation occurred at all dose levels; no ventricular arrhythmias occurred. Acodazole was cleared with a long t1/2 (20.7 h) primarily by nonrenal mechanisms. No alterations in peak plasma levels or excretion were seen in the patients in whom Q-Ti prolongation was detected. No antitumor activity was seen. Further development of acodazole will require delineation of pharmacological means of surppressing this Q-Ti prolongation.

Methotrexate and dipyridamole combination chemotherapy based upon inhibition of nucleoside salvage in humans.

We have carried out a clinical trial in 23 patients to determine whether dipyridamole modulates the clinical effect of methotrexate. This trial was based upon in vitro studies which indicate that dipyridamole potentiates the cytotoxic action of methotrexate through inhibition of thymidine salvage. Methotrexate was given as a bolus injection 24 h after initiation of a high dose dipyridamole infusion. The trial was designed so that methotrexate was escalated in individuals until toxicity occurred and then the methotrexate dose resulting in toxicity was repeated without dipyridamole. During the course of this study the methotrexate dose was escalated from 10 to 130 mg/m2. While individual patient tolerance varied, moderate to severe myelosuppression and/or mucositis occurred frequently in patients receiving the combination with methotrexate doses greater than or equal to 60 mg/m2. Ten of 10 patients who experienced moderate or severe toxicity with the combination had significantly less toxicity when treated with methotrexate alone. Dipyridamole did not increase toxicity by an alteration in methotrexate elimination. The potentiation of methotrexate by dipyridamole in these patients suggests that physiological thymidine levels are sufficient to perturb the clinical effects of methotrexate and that thymidine salvage may represent a mechanism for clinical resistance to methotrexate. These results also suggest that a high dose dipyridamole regimen can be used as a pharmacological approach to test the role of nucleoside membrane flux on the clinical action of other standard chemotherapeutic drugs. Phase II studies testing the clinical efficacy of this combination should use a methotrexate dose of 60 mg/m2 with a provision for methotrexate dose escalation based upon individual patient tolerance.

Modulation of O6-alkylguanine-DNA alkyltransferase-mediated carmustine resistance using streptozotocin: a phase I trial.

1,3-Bis(2-chloroethyl)-1-nitrosourea (BCNU) resistance may be mediated by repair of chloroethylated guanine before stable cross-linking occurs. Guanine adducts may be repaired by the enzyme O6-alkylguanine-DNA alkyltransferase (O6-AGAT). Such repair irreversibly inactivates O6-AGAT. Streptozotocin (STZ) forms adducts at the O6 position of guanine; repair of these adducts consumes O6-AGAT. In vivo STZ potentiates BCNU cytotoxicity. The purpose of this trial was to determine the maximum tolerated dose of BCNU that can be administered together with STZ. The STZ dose was 500 mg/m2/day for 4 days and was not escalated. BCNU was given 4 h after the third dose of STZ at a starting dose of 75 mg/m2. A total of 43 patients were entered in the study. There were 4 dose escalations, reaching a maximum tolerated BCNU dose of 175 mg/m2. At this dose, thrombocytopenia was the dose-limiting toxicity (one patient, 25-49 x 10(9)/liter; 2 patients, less than 25 x 10(9)/liter); neutropenia was less severe (2 patients, 2.0-3.9 x 10(9)/liter, 1 patient, 1.0-1.9 x 10(9)/liter). Two other commonly seen toxicities were elevations in the serum alkaline phosphatase and mild elevations in the serum creatinine. Peripheral blood lymphocyte O6-AGAT levels decreased from a mean of 212 fmol/mg protein pretherapy to 8.2 fmol/mg protein on day 3 prior to BCNU (P = 0.03). Three partial responses were seen. There were no therapy-related fatalities, and toxicity was easily managed. This study established that 150 mg of BCNU can be administered safely together with STZ, 500 mg/m2/day for 4 days. Additional studies are required to determine whether O6-AGAT-mediated BCNU resistance is suppressed.

A phase I study of SR-2508 and cyclophosphamide administered by intravenous injection.

SR-2508, a less lipophilic ane neurotoxic analogue of the nitroimidazole, misonidazole, has exhibited significant chemosensitization properties in preclinical studies with alkylating agents. A phase I trial was carried out to assess toxicity and possible pharmacological interactions of the combination of short infusions of SR-2508 and cyclophosphamide (CP). Patients were randomly assigned to receive either CP alone followed in 3 wk by CP + SR-2508, or CP + SR-2508 followed by CP alone. All additional courses were CP + SR-2508. The maximum tolerated dose of the combination was determined by dose escalation of SR-2508 while the dose of CP remained fixed, initially 1.0 g/m2, and then a second maximum tolerated dose was determined with CP at 1.6 g/m2. One hundred seventeen evaluated courses were administered to 39 patients, the majority of whom had received prior treatment. Somewhat unexpectedly, reversible grade 4 granulocytopenia was the dose-limiting toxicity occurring in four of five evaluable first combination courses at level 6 (SR-2508, 11.3 g/m2; CP, 1.0 g/m2), the initial maximum tolerated dose. SR-2508 enhanced CP-induced myelosuppression as exhibited by the significant difference (p less than 0.001) between the 27 paired courses (CP versus CP + SR-2508) for WBC nadirs over levels 1 to 6. The neurotoxicity encountered was similar to that seen in past clinical trials, being reversible, mild, and usually peripheral in nature. There was one treatment-related death (neutropenic sepsis) on study. No other significant toxicity was seen. SR-2508 exhibited linear pharmacokinetics over the dose range studied. The SR-2508 area under the concentration-time curve increased linearly with dose (r = 0.858; p less than 0.001). No other parameters were dose related. Neither drug appeared to affect the pharmacokinetics of the other, and CP pharmacokinetic values were consistent with those from prior studies. Due to the interaction noted between the two agents and the preclinical data suggesting preferential enhancement of antitumor efficacy under this combination, phase II study appears warranted.

Potentiation of cisplatin antitumor activity using a vitamin D analogue in a murine squamous cell carcinoma model system.

In a murine squamous cell carcinoma (SCC) model, we have demonstrated that both 1,25-dihydroxycholecalciferol (1,25-D3) and the analogue 1,25-dihydroxy-16-ene-23-yne-cholecalciferol (Ro23-7553) have significant in vitro and in vivo antitumor activity. We have examined here the cell cycle effect of 1,25-D3 and Ro23-7553 on SCCVII/SF tumor cells by quantitating nuclear DNA using a detergent-trypsin method via flow cytometry analysis. Both 1,25-D3 and Ro23-7553 resulted in a significant increase of cells in G0-G1, with an accompanying decrease of cells in S phase. The ability to arrest cells in G0-G1 has been exploited by combining Ro23-7553 with the cytotoxic agent cisplatin (cis-diamminodichloroplatinum; cDDP). Using the in vitro clonogenic assay, pretreatment with Ro23-7553 for 24-48 h significantly enhanced cDDP-mediated tumor cell kill as compared to concurrent treatment with Ro23-7553 and cDDP or cDDP alone. To examine the effect of Ro23-7553 and cDDP in vivo, C3H/HeJ mice with 9-14-day SCC tumors were treated either for 3 days with varying i.p. doses of Ro23-7553 or for 7 days continuously through the use of Alzet pumps, and on the last day of Ro23-7553 treatment, cDDP (1-6 mg/kg) was administered. Using the in vivo excision tumor cell clonogenic assay, in which tumors were removed from animals 24 h after cDDP treatment and plated in a clonogenic assay, pretreatment with Ro23-7553 markedly enhanced cDDP-mediated clonogenic tumor cell kill, even at low doses of cDDP as compared to cDDP treatment alone. Similarly, a significant decrease in fractional tumor volume and increase in tumor regrowth delay was observed when animals were pretreated before cDDP with Ro23-7553 as compared to either agent alone. These results demonstrate a significant enhanced antitumor effect with Ro23-7553 pretreatment before cDDP both in vitro and in vivo and suggest that Ro23-7553 may potentiate cDDP cytotoxicity through effects on cell cycle progression.

1,25-Dihydroxycholecalciferol (1,25-D3) inhibits the growth of squamous cell carcinoma and down-modulates p21(Waf1/Cip1) in vitro and in vivo.

1,25-Dihydroxycholecalciferol (1,25-D3) has significant antitumor effects in the murine squamous cell carcinoma (SCC) tumor model in vitro and in vivo. We investigated the basis for this antiproliferative activity and found that, in vitro, 1,25-D3 administration is associated with altered expression of cell cycle regulatory proteins, treatment results in retinoblastoma dephosphorylation, decreased expression of p21(Waf1/Cip1) (p21) mRNA and protein, and increased expression of p27Kip1 (p27) mRNA and protein. Dexamethasone, which acts synergistically with 1,25-D3 to inhibit SCC proliferation, enhanced 1,25-D3-induced down-modulation of p21 without affecting the ability of 1,25-D3 to increase p27 expression. 1,25-D3 did not induce cleavage of poly(ADP-ribose) polymerase. These in vitro data suggest that 1,25-D3 exerts antitumor activity in SCC by perturbing cell cycle progression rather than by inducing apoptosis. In vivo, a 1,25-D3 treatment regimen that results in a decrease in SCC tumor volume is associated with a statistically significant decrease in intratumoral p21 expression. p21 expression is not changed in tumors isolated from control animals or animals treated with a nontherapeutic dose of 1,25-D3. Intratumoral p27 levels were not modulated by 1,25-D3 treatment. Thus, both in vitro and in vivo, 1,25-D3-mediated growth inhibition is associated with p21 down-modulation.

Phase I trial of 5-fluorouracil and dipyridamole administered by seventy-two-hour concurrent continuous infusion.

Forty-seven patients with advanced malignancies were treated with a concurrent 72-h continuous infusion of 5-fluorouracil (FUra) and dipyridamole. The FUra dose was escalated over the dose range of 185 to 3600 mg/m2/day for 3 days. Dipyridamole was administered in a fixed dose of 7.7 mg/kg/day for 3 days. A total of 155 courses of therapy were completed of which there were 31 paired courses of the combination and FUra alone, at the same dose of FUra and in the same patient. This was for purposes of analysis of pharmacokinetics and modulation of FUra toxicity by dipyridamole. Stomatitis was the dose-limiting toxicity experienced by patients entered into this trial. Myelosuppression was not a serious problem. Increasing FUra plasma concentration was associated with greater leukopenia and stomatitis. Dipyridamole did not appear to modulate the systemic toxicity of FUra. The pharmacokinetics of FUra were altered by the concurrent administration of dipyridamole. Dipyridamole promoted the total body clearance of FUra which resulted in lower mean steady-state FUra plasma concentrations when compared with courses of FUra alone administered at the same dose level. These differences were statistically significant over the course of the trial. For courses of the combination, FUra exhibited linear pharmacokinetics over the dose range studied. Total body clearance of FUra declined slightly at the higher dose levels, but the differences were not significant. For courses of FUra alone, total body clearance was significantly decreased above the dose level of 2300 mg/m2/day. At the maximal tolerated dose of FUra, 2300 mg/m2/day x3, mean steady-state FUra plasma concentration and total body clearance were 6.6 microM and 122 liters/h/m2, respectively, for courses of the combination. The corresponding pharmacokinetic parameters were 7.4 microM and 103 liters/h/m2 for courses when FUra was given alone. Further evaluation of the utility of this regimen and basis of these pharmacokinetic observations appear warranted.

Reversible increase in serum alpha-fetoprotein content associated with hepatic dysfunction during chemotherapy for seminoma.

Serial monitoring of the serum content of the beta subunit of human chorionic gonadotropin (beta hCG) and alpha-fetoprotein (alpha FP) is useful in the initial staging of germ cell tumors and assessing the response to treatment. An increase in either marker during or following treatment almost always heralds disease progression and indicates the need for additional therapy. We report two patients in whom substantial increases in the serum content of AFP occurred during chemotherapy for advanced seminoma. Hepatic dysfunction was present in both patients; in one patient, a chronic carrier of hepatitis B virus, the liver dysfunction was associated with reactivation of hepatitis B manifested by anicteric hepatitis and hepatitis B e antigen positivity. Marked tumor regression had occurred in both patients, and chemotherapy was discontinued in spite of the elevated alpha FP level. The alpha FP content in the serum gradually returned to normal, and hepatic dysfunction resolved. Both patients remain free of disease 15 and 17 months following the last chemotherapy treatment. These cases illustrate that hepatic dysfunction and alpha FP production may occur during chemotherapy and that increases in serum alpha FP content must be interpreted with caution since the elevated alpha FP level does not always indicate progression of germ cell tumors.

Painful gynecomastia following cytotoxic therapy for testis cancer: a potentially favorable prognostic sign?

Ninety-six patients who received cytotoxic chemotherapy for germ cell neoplasms of the testis were studied. Painful gynecomastia developed in eight patients (8%) between 6 and 24 weeks after the initiation of cytotoxic therapy (mean 18 wk). Serum content of the beta subunit of human chorionic gonadotropin was normal in each patient when gynecomastia developed. Gynecomastia occurred following cytotoxic therapy for advanced disease in seven patients, and one patient was receiving adjunctive drug therapy for stage I disease. Six of the seven patients with advanced disease were in complete remission when gynecomastia developed; survival was superior in patients who developed treatment-related gynecomastia compared to those patients who did not (p less than 0.05). Gynecomastia may occur in adult males after cytotoxic therapy for testis cancer; such gynecomastia does not necessarily indicate recurrent malignancy and may be a favorable prognostic sign.

Importance of continued testicular suppression in hormone-refractory prostate cancer.

PURPOSE: Patients in whom prostate cancer progresses despite testicular androgen ablation are generally said to have cancers that have become resistant to hormonal maneuvers. If androgen suppression has been pharmacologic, this therapy is often stopped before consideration of other systemic treatments. This exploratory study sought clinical correlates of experimental evidence that there may be substantial acceleration of tumor growth after cessation of androgen suppression. MATERIALS AND METHODS: A retrospective multivariate analysis was performed on survival data for 341 patients treated on four clinical trials of secondary therapy for hormone-refractory prostate cancer. Factors included in the model were recent weight loss, age, performance status, disease site (soft tissue v bone-dominant), prior radiotherapy, and continued androgen suppression v discontinued exogenous endocrine therapy. RESULTS: Recent weight loss, age, performance status, and disease site were important prognostic factors for survival duration in hormone-refractory prostate cancer. Correcting for these factors, continued testicular androgen suppression was also an important predictor of survival duration in all data sets examined. CONCLUSION: This retrospective study showed a modest advantage in survival duration for men with hormone-refractory prostate cancer who continued to receive testicular androgen suppression. The hypothesis that continued hormonal maneuvers can still affect survival in this group warrants examination in prospective trials.

Hypercalcemia and neuroendocrine carcinoma of the prostate: a report of three cases and a review of the literature.

PURPOSE: Hypercalcemia is a rare complication of prostate cancer, and no definite association with any histologic subtype of prostatic malignancy has been documented. We have recently seen three patients who developed hypercalcemia in the setting of prostate cancer. All had neuroendocrine carcinoma of the prostate (NCPs), which prompted an exploration of the potential association of hypercalcemia with NCP. DESIGN: An extensive review of literature published in the English-language was conducted to identify cases of hypercalcemia associated with prostate cancer and well-documented cases of NCP. RESULTS: We found 17 reported cases of hypercalcemia clearly associated with prostate cancer and a total of 61 cases of well-documented NCP. Including our cases, 11 of the 20 reported cases of hypercalcemia associated with prostate carcinoma were in patients with neuroendocrine carcinomas. CONCLUSION: Hypercalcemia in the setting of prostate cancer should prompt a search for unusual histologies.

Factors influencing options in primary breast cancer treatment.

Primary breast cancer treatment is determined by tumor factors and by patient preference. Breast cancer treatments that preserve the cosmetic appearance of the breast are appealing and effective for appropriately selected patients; long-term survival following tumor excision and breast irradiation appears to be comparable to that for mastectomy. Since April 1981, when a protocol was developed and treatment options were offered, factors influencing treatment selection have been analyzed in 206 consecutive primary breast cancer patients. Mastectomy was dictated by tumor-related factors in 96 patients (47%); 110 patients (53%) had the option of mastectomy or conservation--tumor excision plus radiotherapy to the breast. Among these 110 eligible patients, 54 chose conservation (49%) and 56 chose mastectomy (51%). Intraoperative findings for ten patients electing conservation necessitated mastectomy, so conservation was accomplished for 44 (21%) of those treated for breast cancer. Beginning in July 1982, breast cancer patients took a battery of psychosexual assessments before any operation (Profile of Mood States [POMS], Health Locus of Control Scale [HLCS] Locke-Wallace Marital Adjustment Test [MAT], Psychosocial Adjustment to Illness Scale [PAIS], Derogatis Sexual Function Inventory [DSFI], Millon Clinical Multiaxial Inventory [MCMI], and a Breast Cancer Information Test [BCIT]). Comparisons of psychologic and demographic variables were made between patients who chose mastectomy and those who chose conservation. No demographic variable was statistically significantly related to choice, although older women tended to select mastectomy more than younger women. Compared with those who elected conservation, women who elected mastectomy were more tense and anxious (P less than .01), more introverted (P less than .01), felt more depressed and dejected (P less than .05), and reported more sexual problems (P less than .05). Those who elected conservation valued their physical appearance more highly (P less than .01) and were generally more self-interested (P less than .05). Mastectomy was dictated by medical considerations for approximately half of patients with breast cancer. Among candidates for breast conservation, the importance of retaining the breast appeared to be determined to a significant degree by measurable psychological factors.

Pharmacokinetic and pharmacodynamic analysis of fluorouracil during 72-hour continuous infusion with and without dipyridamole.

During a phase I trial of 3-day simultaneous continuous intravenous infusions of varying doses of fluorouracil (5FUra) and 7.7 mg/kg/d of dipyridamole, we examined the relationships between 5FUra dose and steady-state plasma concentration (Css) and the percentage reduction in WBCs, as well as the percentage frequency of stomatitis. The 5FUra was administered at doses ranging from 185 mg/m2/d times three to 3,600 mg/m2/d times three. In 42 patients, 86 cycles of 5FUra plus dipyridamole and 28 cycles of 5FUra alone were analyzed. The Css of 5FUra varied even within the same dose level. When patients receiving the same 5FUra dose were considered, the interpatient coefficient of variation of 5FUra Css in cycles of 5FUra plus dipyridamole was 23% +/- 4.2%. For courses of 5FUra alone, the coefficient of variation of 5FUra was 15.6% +/- 6.5%. When the occurrence of any degree of stomatitis was related to the Css 5FUra, with patients grouped in cohorts of 2-mumol/L increments, the following equations accurately described the frequency of stomatitis: for 5FUra plus dipyridamole, percentage frequency of stomatitis = 100(1-e-0.114Css), r2 = 0.88; for 5FUra alone, percentage frequency stomatitis = 100(1-e0.122Css), r2 = 0.80. When 5FUra dose was substituted for Css, these relationships were as follows: percentage frequency of stomatitis = 100(1-e-0.00031 [dose]), r2 = 0.85; and percentage frequency of stomatitis = 100(1-e-0.00051 [dose]), r2 = 0.80. When the relationship between the percentage reduction in WBC and Css 5FUra was examined, statistically significant relationships were also apparent: for 5FUra plus dipyridamole, percentage reduction in WBC = 100(1-e-0.085Css), r2 = 0.46; for 5FUra alone, percentage reduction in WBC = 100(1-e-0.060Css), r2 = 0.61. When 5FUra dose was substituted for Css, these relatinships were as follows: percentage reduction in WBC = 100(1-e-0.00023 [dose]), r2 = 0.40; percentage reduction in WBC = 100(1-e-0.00024 [dose]), r2 = 0.65. The relationship between either Css 5FUra or dose 5FUra and either stomatitis or myelosuppression were also well described by the modified Hill equation (J Theor Biol 20:171-201, 1968). These analyses indicate that it should be possible to develop therapeutic regimens wherein 5FUra is administered to achieve a targeted Css determined by the risk and severity of toxicity deemed acceptable.

Randomized prospective comparison of intraventricular methotrexate and thiotepa in patients with previously untreated neoplastic meningitis. Eastern Cooperative Oncology Group.

PURPOSE: This prospective randomized cooperative group study was conducted in patients with neoplastic meningitis treated with intrathecal methotrexate or thiotepa to assess response rates and survival, prognostic factors, and the toxicity of these regimens. PATIENTS AND METHODS: Fifty-nine adults with nonleukemic malignancies, performance status of 0 to 3, and positive CSF cytologies were assigned to receive intrathecal methotrexate (10 mg) or thiotepa (10 mg) twice weekly. Radiation, was administered to mass lesions and/or symptomatic sites and appropriate systemic therapy was given concomitantly. RESULTS: Fifty-two patients were assessable. Most were female (79%), nonambulatory (77%), had been pretreated with radiation (52%) and chemotherapy (77%), and had evidence of systemic disease (65%). Most primary cancers were of the breast (48%), lung (23%), or lymphatics (19%). Treatment arms were well balanced, except that more patients randomized to methotrexate had breast cancer (61% v 33%) and were without evidence of systemic cancer (21% v 4%). No patient had important neurologic improvement with therapy, and 75% deteriorated neurologically within 8 weeks of initiating therapy. Survival ranged from 4 days to 110.5+ weeks. Median survival for patients receiving methotrexate was 15.9 weeks and 14.1 weeks for patients treated with thiotepa. Factors predictive of shorter survival included progressive systemic disease (P = .0005), poor performance status (P = .03), and significant cranial nerve palsies (P = .02). Although serious toxicities were similar, mucositis (P = .04) and neurologic complications (P = .008) were more common in patients who received methotrexate. CONCLUSION: The efficacy and overall toxicities of intraventricular methotrexate and thiotepa seem similar and neither reverses fixed neurologic deficits. Early diagnosis and treatment and new therapeutic approaches are needed to improve the outcome for patients with neoplastic meningitis.