Epidermal growth factor receptor ectodomain in the urine of patients with squamous cell carcinoma

In this study we determined the levels of the epidermal growth factor receptor (EGFR) in the urine of patients with squamous cell carcinoma compared to levels in the urine of normal volunteers and patients with nonsquamous cell carcinoma. A 24-h urine specimen was collected from 50 normal volunteers, 50 patients with nonsquamous cell carcinoma, and 42 patients with squamous cell carcinoma. An ELISA using mAbs to the external domain of the EGFR was used to measure levels of the receptor in the urine samples. Measurement of the EGFR ectodomain in the 24-h urine specimens showed detectable levels in 15 (36%) of 42 squamous cell carcinoma patients compared to 3 (6%) of 50 controls and 8 (16%) of 50 nonsquamous patients. It was also observed that 10 (53%) of 19 patients with metastatic squamous cell carcinoma had detectable EGFR ectodomain levels compared to 5 (22%) of 23 squamous cell patients with localized disease. Thus, we concluded that the EGFR ectodomain was detectable in the urine in a significantly higher number of patients with squamous cell carcinoma than normal volunteers or patients with nonsquamous cell carcinoma.

Letrozole (CGS 20267). A phase I study of a new potent oral aromatase inhibitor of breast cancer

BACKGROUND

Letrozole (CGS 20267), a triazole derivative, is a new, once-daily, oral nonsteroidal inhibitor of aromatase activity.

METHODS

In this Phase I trial, 23 heavily pretreated postmenopausal patients with metastatic breast cancer received letrozole at doses ranging from 0.1 to 5.0 mg once daily.

RESULTS

No hematologic, biochemical, or significant clinical toxicity was encountered. Serial steroid measurements were determined in 19 of these patients. Letrozole at all doses tested produced a marked suppression of plasma estrone, estradiol, estrone sulfate, and urine estrone and estradiol. This was observed within 24 hours of the initial dose of letrozole and resulted in a greater than 90% suppression of plasma and urinary estrogen levels within 2 weeks. Letrozole appears to be highly selective in its action and does not compromise glucocorticoid or mineralocorticoid production or thyroid function. Of the 21 evaluable patients, there were 2 with partial responses and 7 with stable disease.

CONCLUSIONS

Letrozole is a well tolerated, potent, and specific inhibitor of estrogen biosynthesis in postmenopausal patients with metastatic breast cancer.

The management of hypercalcemia of malignancy

Hypercalcemia (HCM) occurs in 10-15% of all malignancies, predominantly in patients with solid tumors. This metabolic complication leads to significant morbidity and impairment of quality of life. Recent insights into the pathophysiology of HCM include an understanding of the role of parathyroid-hormone-related peptide and several cytokines secreted by tumors. The osteoclast plays a central role as the final common pathway through which these hormones and cytokines act to cause bone lysis. These findings have led to the development of new treatment strategies. Foremost among these has been the introduction of agents such as the newer bisphosphonates and gallium nitrate, which are potent inhibitors of osteoclast-mediated bone resorption. The clinician can now choose from an array of therapeutic approaches based on a consideration of the mechanisms of action, individual clinical circumstances, efficacy, toxicities and costs of available agents. In addition to their use in the management of HCM, non-toxic drugs that effectively inhibit osteoclast function, such as the bisphosphonates, are playing an emerging role in the palliative treatment of the more common clinical problems of painful lytic bone metastases and osteoporosis.

The effects of long term fadrozole hydrochloride treatment in patients with advanced stage breast cancer

Fadrozole hydrochloride at a dose of 2 mg b.i.d. has been shown to be an effective aromatase inhibitor in advanced stage breast cancer patients as determined by its ability to significantly suppress endogenous estrogen biosynthesis over a 12-week period. Continued suppression of circulating estrogen levels over a prolonged period has not yet been examined in published reports. In this study, we report the extended use of fadrozole hydrochloride at a maintenance dose of 2 mg b.i.d. in a cohort of 11 patients extending to 973 days of therapy. Results show that the degree of suppression of plasma and urinary estrogens was maintained in all patients throughout the extended period of drug use. Continued estradiol suppression of over 50% or greater from baseline was observed, as was continued suppression of estrone to over 80% from baseline. Cortisol determinations after 9 months of treatment showed no suppression from baseline. The aldosterone values and responses to cortrosyn stimulation continued to be suppressed as first noted following the initial 3 months of the core clinical trial. Objective tumor response noted in the core clinical trial did not change until disease progression. These findings suggest that fadrozole hydrochloride maintains its ability to suppress the aromatase enzyme during long term use. No observable escape from suppression of plasma and urinary estrogens occurred during prolonged treatment.

The efficacy of CGS 20267 in suppressing estrogen biosynthesis in patients with advanced stage breast cancer

The pharmacologic inhibition of aromatase activity has been the focus of clinical trials in patients with advanced stage breast cancer. Recent developments with imidazole compounds that inhibit aromatase activity suggest their clinical use as potent inhibitors of estrogen biosynthesis in postmenopausal breast cancer patients. In this Phase I, open-label, dose-range finding study, we examined the inhibitory potency of CGS 20267 on blood and urine levels of estradiol, estrone and estrone sulfate in 8 patients with metastatic breast cancer. Studies included evaluation of adrenal and thyroid function to look for evidence of general hydroxylase inhibition at dose levels effective for aromatase blockade. Patients were administered CGS 20267 at doses of 0.1 and 0.25 mg, once a day in ascending doses over a 12-week period. Preliminary data reveal that CGS 20267 elicits a striking suppression in plasma estradiol, estrone and estrone sulphate which was observed in some patients as quickly as within 24 h of the first dose. Estrogen suppression of over 90% was achieved within 2 weeks of therapy. No alterations in either baseline or ACTH (cortrosyn) stimulated cortisol and aldosterone levels were observed through the 12 weeks of therapy. In addition, 24 h urine sodium and potassium values were not appreciably altered during therapy. We conclude that CGS 20267 is a potent, specific inhibitor of estrogen biosynthesis in postmenopausal patients with metastatic breast cancer and effectively reduces blood and urine estrogens to undetectable levels.

Prognostic value of breast cancer aromatase

The estrogen receptor, progesterone receptor, and intratumoral aromatase content of 127 breast carcinomas were determined. Patients whose tumor contained either estrogen or progesterone receptors had a longer disease-free interval, but no difference in survival was observed. Measurable aromatase activity was detected in 78 of 113 (69%) tumors. There was no relationship between aromatase activity and disease-free interval or survival.

A decision-theoretic evaluation of early stopping rules

We consider the decision-theoretic evaluation of early stopping rules for clinical trials. We describe a hypothetical phase III, two-arm trial with interim analysis, modelling it as a decision problem. We present methods for constructing a group-sequential test that is optimal for a given utility and prior distribution, and for determining a utility and prior under which a given test is optimal. Using our methods, we construct optimal tests for utilities and priors representing a variety of perspectives: a view that seeks to maximize the long-run response rate, a view that seeks to maximize the chance of a correct decision, and a personal view elicited from a medical oncologist. Characteristics of the optimal rules are sensitive to the input utilities and priors, and their critical values and sampling properties can differ markedly from those of group-sequential tests. We also compute utility functions and priors under which some standard group-sequential stopping rules are optimal. Our results suggest that the group-sequential tests, considered as decision procedures, imply a symmetry in the decision problem that is inconsistent with the response-rate perspective. We conclude that decision theory is a useful device for illuminating the sometimes conflicting goals of clinical research, and that the use of decision theory in designing clinical trials could lead to marked changes in statistical criteria for early termination.

Corynebacterium parvum versus bacille Calmette-Guérin adjuvant immunotherapy of stage II malignant melanoma

Two separate studies have been reported comparing Corynebacterium parvum and bacille Calmette-Guérin (BCG) as adjuvant immunotherapy for stage II melanoma patients (The Milton S. Hershey Medical Center, 48 patients; Southeastern Cancer Study Group [SECSG], 162 patients). As the criteria for patient selection and drugs used were similar, we have pooled the data to analyze the effects of these two treatments. Both studies used BCG (Tice, Chicago, IL) 3 x 10(8) live organisms per treatment by Tine technique and C parvum (Burroughs-Wellcome, Triangle Park, NC) subcutaneous at a dose of 4 mg/m2 (SECSG) or 5 micrograms/m2 (Hershey) per treatment. The only difference in these studies was the frequency of immunization, with patients in Hershey receiving 22 doses and the SECSG patients receiving 55 doses during the 2-year period of treatment. Kaplan-Meier life-table analysis for the 210 patients shows a prolonged disease-free interval for patients treated with C parvum (P = .02, two-sided Mantel procedure). In similar fashion, patients treated with C parvum had an improved survival rate (from all causes) when compared with BCG-treated patients (P = .012). An analysis of the results for the 170 patients for which the number of positive nodes was available was performed using Cox's model, with nodes as a stratification variable and with covariates of place, treatment, age, and sex. In this analysis, an observed benefit for C parvum on the disease-free interval had a P value of .37 while the benefit of C parvum on the survival times (from all causes) had a P value of .04. When the same analysis was performed using only patients aged younger than 60 years, the observed benefit of C parvum on disease-free interval had a P value of .08 and the benefit of C parvum on survival times (from all causes) had a P value of .008.

Somatostatin analogues in the treatment of breast and prostate cancer

Newly developed somatostatin analogues may be useful agents in the treatment of breast and prostate cancer. Potential mechanisms of antitumor action include suppression of circulating levels of trophic hormones and growth factors as well as direct effects at the tumor level, potentially involving autocrine/paracrine mechanisms. Pilot clinical trials conducted in heavily pretreated women with advanced breast cancer indicate that SMS 201-995 (Sandostatin R) has minimal toxicity and moderately suppresses stimulated growth hormone secretion and basal somatomedin-C level. Somatostatin analogues have also been found to retard the growth of experimental prostate cancer, particularly when used in combination with LHRH analogues. The therapeutic efficacy of these compounds used alone or in combination with other agents in the treatment of breast and prostate cancer remains to be established in larger clinical trials involving less heavily pretreated patients.

Advanced head and neck cancer: low-dose, split-course radiation therapy and simultaneous infusion of 5-fluorouracil and cisplatin

Twenty-three patients with advanced untreated head and neck cancer, nine patients with recurrent cancer, and six patients with recurrent cancer who underwent surgery and had postoperative persistence of tumor were treated with three 2-week courses of irradiation (1,500 cGy in 10 fractions each) concurrently with cisplatin and a 5-day infusion of 5-fluorouracil. A fourth 2-week course of irradiation (2,000 cGy in 10 fractions) brought the final tumor dose to 6,500 cGy. Twenty patients in the untreated group and three patients in the recurrent group (33%) had a complete response. There were 10 local recurrences in the untreated group (43%), seven in the recurrent group (78%), and three in the persistent group (50%). At 17 months after the start of treatment, the survival rate for the untreated patients was 51%, for the patients in the recurrent group it was 11%, and for the patients in the persistent group it was 20% (P = .03). Most patients experienced toxicity, including nausea, vomiting, weight loss, and mucositis. Clinical trials are necessary to determine whether simultaneous chemotherapy and radiation therapy is an improved method of treatment for advanced head and neck cancer.

The effects of CGS 16949A, an aromatase inhibitor on adrenal mineralocorticoid biosynthesis

The family of cytochrome P450 enzymes that mediates steroid hydroxylations are distinct but structurally related proteins. Inhibitors of these steroidogenic steps generally exhibit only relative and dose-related specificity. We evaluated an imidazole, cytochrome P450-related inhibitor, CGS 16949A, in postmenopausal patients with metastatic breast cancer. While a relatively specific aromatase inhibitor at daily dosages of 1-2 mg, CGS 16949A significantly blunted cortisol responses to ACTH at a dose of 16 mg daily. To further evaluate other inhibitory effects of this drug, we determined blood levels of aldosterone (ALDO) and 18-hydroxycorticosterone and their respective urinary metabolites, tetrahydroaldosterone and tetrahydro-18-hydroxy-11-dehydrocorticosterone in 16 postmenopausal women receiving CGS 16949A. At a dose of 16 mg/day, CGS 16949A produced significant (P less than 0.001) suppression of both basal and ACTH-stimulated ALDO production. This was accompanied by a significant rise in the blood 18-hydroxycorticosterone/ALDO ratio (11.4 +/- 0.19; normal, less than 2; P less than 0.001), consistent with a corticosterone methyloxidase type II inhibition. A similar significant elevation (7.5 +/- 1.2; normal, less than 5; P less than 0.001) in the urinary tetrahydro-18-hydroxy-11-dehydrocorticosterone/tetrahydroaldosterone ratio was also observed. These results suggest that CGS 16949A is a potent inhibitor of the corticosterone methyloxidase type II enzyme at a dose of 16 mg daily. At doses of 1-2 mg daily, CGS 16949A blocks aromatase without altering basal aldosterone production and, thus, exhibits dose-related specificity.

A phase I trial of CGS 16949A. A new aromatase inhibitor

CGS 16949A is a new, nonsteroidal competitive inhibitor of the aromatase enzyme. In this Phase I trial, 16 heavily pretreated postmenopausal patients with metastatic breast cancer were treated with escalating doses of CGS 16949A from 0.6 to 16 mg total daily oral dose. No hematologic, biochemical, or significant clinical toxicity was encountered. Endocrinologic and pharmacologic data were available from 12 of these patients. Maximum inhibition of estrogen biosynthesis was observed at a dose of 2 mg CGS 16949A daily. At this dose, the inhibition of estrogen biosynthesis was equivalent to 1000 mg aminoglutethimide (AG). The fall in plasma and urinary estrogens without a concomitant drop in androgens confirmed the specific blockade of aromatase activity. At doses of 4 to 16 mg daily, CGS 16949A appeared to inhibit the C21-hydroxylase enzyme as well. The t1/2 of CGS 16949A in the circulation was 10.5 hours. Of 16 evaluable patients there were two partial responses and seven patients with stable disease.

FAM chemotherapy +/- aminoglutethimide in the treatment of pancreatic carcinoma

Human pancreas contains receptors for estrogens and androgens as well as aromatase activity. FAM chemotherapy was administered to 14 patients with pancreatic cancer (seven at Stage IV). The median survival of these patients was 24.4 +/- 4.8 weeks. FAM chemotherapy plus aminoglutethimide/hydrocortisone (AG/HC) (250 mg bid AG + 20 mg bid HC) was administered to 14 patients (seven at stage IV). The median survival of this group was 17.3 +/- 2.9 weeks (P = 0.74 vs FAM alone). We conclude that addition of AG/HC does not add to the survival of patients with carcinoma of the pancreas treated with chemotherapy.

Endocrine effects of combined somatostatin analog and bromocriptine therapy in women with advanced breast cancer

In this pilot clinical trial conducted in 10 postmenopausal women with advanced breast cancer, we evaluated the endocrine effects and toxicity of combined somatostatin analog and dopaminergic therapy in the attempt to suppress both growth hormone (GH) and prolactin (PRL) secretion. The patients' mean age was 63 years (range: 54-77) and the average number of previous treatments was 4.8 +/- 2 (SD). All patients were treated with the somatostatin analog SMS 201-995 (100-200 micrograms s.c. in a.m. and h.s.) and bromocriptine (2.5 mg orally twice a day). During treatment, GH levels following provocative testing (either L-DOPA or insulin-induced hypoglycemia) were suppressed in 7/9 patients. Basal somatomedin-S (Sm-C) levels declined in 6/9 women. Both GH and Sm-C levels decreased in 4 patients, while in the remaining 5 only one of the two parameters was lowered on treatment. PRL secretion (during provocative TRH testing) was almost totally abolished in 8/9 patients. The treatment did not affect circulating levels of FSH, LH, E1, E2, E1-S, T4, T3RU, or cortisol. Seven patients experienced no side effects. Nausea occurred in 3, but was severe enough in only one to require discontinuation of therapy. One patient experienced disease stabilization consisting of less than 50% regression of skin nodules and pleural effusion, a decline in CEA titer, and an improved performance status lasting 7 months. We conclude that combined SMS 201-995 and bromocriptine therapy is safe and frequently suppresses GH and PRL secretion. Its role in the treatment of metastatic breast cancer should be tested in patients with less advanced disease.

Chemotherapy plus RA233 in the treatment of oat cell lung cancer

One hundred and one patients with oat (small) cell lung cancer have been treated with CAVE [Cytoxan, Adriamycin, Vincristine, and etoposide (VP-16)] chemotherapy +/- RA233 (a platelet-inhibiting agent). There was no difference in disease-free interval, pattern of relapse, or survival between groups.

A phase I study of hepatic arterial infusion using difluoromethylornithine

Ten patients with metastatic disease to the liver were treated with difluoromethylornithine (DFMO) administered by continuous hepatic arterial infusion. Two of nine evaluable patients had an objective partial response. Stable disease was recorded in three patients. Ototoxicity was encountered in all patients who received a daily dose of DFMO equal to or greater than 1.0 g/m2.

Marked heterogeneity of aromatase activity in human malignant melanoma tissue

The prognosis from human malignant melanoma varies according to sex and to multiple histologic, biologic and cell kinetic parameters. Thus melanomas exhibit a major degree of heterogeneity in their biologic properties and further characterization of their biochemical heterogeneity should yield important information. The present study sought to demonstrate the activity of a biochemical marker of estrogen synthesis, the aromatase enzyme, in melanoma tissue and to determine its range of activity. Initially, we validated a highly sensitive radiometric assay for aromatase by comparing it with a direct product isolation method. We detected production of 417 pmol/g protein/h of estrone and 37.3 pmol/g protein/h of estradiol by direct product isolation in a human melanoma and 398 pmol estrone/g protein/h by the radiometric assay. The activity present was blocked by similar amounts of the aromatase inhibitor, aminoglutethimide, as were necessary to block placental, breast cancer, and rat brain aromatase activity. We then assayed aromatase radiometrically in 19 human melanomas and found measurable activity ranging from 9 to 398 pmol estrone/g protein/h in 15 tissues. No relationship with the patient's age or sex was demonstrated. The activity exceeded by 2-fold that previously detected in 49/61 human breast cancers. This study identified a marker enzyme in melanoma tissue which varied by 40-fold among human tumors. Correlation of aromatase activity with prognosis and response to various types of therapy is now necessary to establish the biologic relevance of this finding.

Correlation of aromatase activity with histological differentiation of breast cancer--a morphometric analysis

Differentiation is a term that indicates the degree to which a tumor resembles histologically the tissue or cell of origin. A system to quantitate the proportion of breast cancer cells participating in glandular differentiation or remaining within ducts was employed. The degree of tumor differentiation of 58 primary breast cancers was correlated with estrogen (ER) and progesterone receptors (PR) and tumor aromatase activity. There was a significant association between tumor differentiation (greater than or equal to 2% cancer cells exhibiting glandular differentiation) and the presence of ER or PR in tumors. Conversely, there was no correlation between tumor differentiation and measurable tumor aromatase activity.

Unmet needs of persons with cancer in Pennsylvania during the period of terminal care

A stratified random sample of recent cancer deaths was drawn from the Pennsylvania death registry, and 433 family members or close friends were interviewed concerning unmet needs during the last month of life. It was estimated that 72% of persons who died of cancer in Pennsylvania experienced at least one unmet service need during this period. The most frequently reported was help with activities of daily living, estimated at 42% of cancer deaths, involving over 11,000 persons each year in the state. There were significantly more unmet needs during the terminal period, compared with just after diagnosis, in activities of daily living, obtaining health care, transportation, and problems with medical staff. Our findings indicate a need to increase a broad range of support programs during the terminal period, especially of home-care services.

A phase I trial of recombinant human gamma interferon (IFN-gamma 4A) in patients with advanced malignancy

We report a Phase I study in 39 cancer patients of the tolerance and biologic activity of 47 intravenous (i.v.), intramuscular (i.m.), and subcutaneous (s.c.) treatments with recombinant methional gamma interferon (IFN-gamma 4A) which most closely resembles the natural material produced by T lymphocytes. Patients were treated with IFN-gamma 4A 5 days a week for 2 weeks. After a 2-week rest period, patients were placed on the same dose of drug three times a week. The most common side effects--fever, chills, malaise, myalgias, and nausea and vomiting--were seen with all routes of administration. Reversible increases in hepatic transaminase and decrease in granulocytes counts were seen. The dose-limiting toxicities observed were malaise and orthostatic hypotension. The maximum tolerated dose was 500-1,000 micrograms/M2/day. The t1/2 of IFN-gamma 4A in the circulation was 20 min after i.v. injection. No blood levels were detected after i.m. or s.c. injection. Antibody against IFN-gamma 4A increased in three patients. A complete response was observed in one patient with pulmonary metastases from renal cell carcinoma.

Aromatase activity in primary and metastatic human breast cancer

Aromatase activity was measured in 104 primary and 24 metastatic breast cancer patients. The assay employed quantitates the production of 3H water release from 1 beta-[3H]androstenedione after aromatization. Of 104 human primary breast tumors studied, 64 contained measurable aromatase activity, ranging from 5-70.5 pmol estrone formed/g protein/hour. In primary breast cancers there was no difference in levels of aromatase activity when analyzed by menstrual status or age by decade. Aromatase activity was similar in small and large primary tumors. The median aromatase activity of primary breast tumors (8.6 pmol/g/h) was similar to that found in metastatic breast cancer deposits (12.0 pmol/g/h). Aromatase activity did not correlate with either estrogen (ER) or progesterone (PR) receptor concentration in the tissues assayed. In this regard there were 33 ER- PR- tumor biopsies. Twelve of these 33 tumors contained aromatase activity greater than 10 pmol/g/hour.

A randomized trial of aminoglutethimide +/- estrogen before chemotherapy in advanced breast cancer

Recent reports have suggested that the sensitivity to chemotherapy of endocrine-dependent breast cancer may be enhanced by transient exposure to hormonal stimulation. To test this concept, 39 postmenopausal women with proven metastatic breast carcinoma and measurable disease were entered into this prospective, double-blind trial; 35 are currently evaluable. All patients were continuously treated with aminoglutethimide and hydrocortisone to lower estrogen production, plus cyclic chemotherapy. Patients in the "stimulation" arm received in addition, Estrace 2 mg b.i.d. sublingually for 3 days before and on the day of chemotherapy. Estrace administration appeared to accelerate tumor growth as demonstrated by increased bone pain, hypercalcemia, and growth of skin lesions. Response rates, response duration, and survival were similar in the stimulation and control groups.

Addition of etoposide to cyclophosphamide, doxorubicin, and vincristine for remission induction and survival in patients with small cell lung cancer

A total of 116 patients with small cell lung cancer were randomized to receive either: cyclophosphamide, 750 mg/m2, doxorubicin, 50 mg/m2, and vincristine, 2 mg iv (Regimen A), or the same drugs plus etoposide, 100 mg/m2 iv daily for 2 days (Regimen B) every 3 weeks. Complete responders received whole-brain radiation therapy. The overall response rates were 50% for Regimen A and 65% for Regimen B (P less than 0.05). The complete response rates were 18% for Regimen A and 44% for Regimen B (P less than 0.01). For patients with limited disease, the complete responders were 35% on Regimen A and 52% on Regimen B (P = 0.26); for those with extensive disease, the complete responders were 0% on Regimen A and 35% on Regimen B (P = 0.002). The median survival for complete responders was 17 months on Regimen A and 20 months on Regimen B. The difference is not statistically significant. Toxicity was tolerable for both groups; however, it was greater for the etoposide arm. We conclude that although etoposide improves the overall response rates in patients with small cell lung cancer, especially those with extensive disease, the addition of this drug does not lead to improved survival.