A randomized attempt to increase the efficacy of cytotoxic chemotherapy in metastatic breast cancer by hormonal synchronization

Inflammatory Component: A Worsening Factor in Locally Advanced Breast Cancer Treated by Radiotherapy and Systemic Therapy

Locally advanced and inflammatory carcinomas of the breast are two distinct entities with clear differential clinical criteria. We described a particular type of locally advanced breast cancer which, during its evolution, developed inflammatory characteristics limited to a small area of the skin. It, therefore, did not meet the common diagnostic criteria of inflammatory carcinoma. In our series, studied from December 1977 to January 1987, we treated 59 cases of locally advanced breast cancer and 105 cases of locally advanced breast cancer with an inflammatory component. The actuarial overall survival was 53.3 % at 5 years and 38.4 % at 7 years. Differences were observed when the two tumor types were compared. Specifically, locally advanced breast cancer with an inflammatory component had a worse prognosis, poorer survival and poorer disease-free rates than locally advanced breast cancer.

A Randomized Trial of Chemotherapy with or without Estrogenic Recruitment in Locally Advanced Breast Cancer

The present phase III trial was carried out to verify whether a kinetic recruitment induced by low doses of diethylstilbes-trol (DES) could increase the killing efficacy of chemotherapy in patients with locally advanced breast cancer. One-hundred and seventeen untreated patients with locally advanced breast cancer (stage IIIA/IIIB) were randomized to receive 3 courses of primary chemotherapy consisting of cyclophosphamide (600 mg/m2 i.v.), doxorubicin (50 mg/m2 i.v.) and fluorouracil (600 mg/m2 i.v.) (CAF) on day 1, or DES-CAF (DES, 1 mg orally days 1-3, CAF on day 4). The courses were repeated every 3 weeks. The patients who achieved an objective response were submitted to mastectomy followed by 3 courses of CAF alternated with 3 courses of CMF (cyclophosphamide, 600 mg/m2 i.v.; methotrexate, 40 mg/m2 i.v.; fluorouracil, 600 mg/m2 i.v.), with or without DES. The two treatment arms were well balanced in terms of clinical and pathologic features. There was no significant difference in response rates to induction chemotherapy between the two treatment arms (objective response rate, 63.3% for CAF and 56.1% for DES-CAF). Median overall survival was 49 and 47 months and median progression-free survival was 24 and 21 months for CAF and DES-CAF patients, respectively. Toxicity was not significantly different in the two groups, with the exception of leukopenia: DES chemotherapy was significantly more myelotoxic than the standard treatment, which resulted in a significant reduction in the actual dose intensity. In spite of the attractive experimental evidence, we conclude that so far there is no clinical advantage in the combination of estrogen and chemotherapy. Further research is needed to investigate different schedules of chemotherapy and hor-mones, or to test the possibility of combining various mitogens.

Tidal chemotherapy in premenopausal patients with hormone receptor positive breast cancer

Neoadjuvant chemotherapy remains an inseparable part of systemic therapy for hormone receptor positive (HR+) advanced breast cancer. However, efficacy of neoadjuvant chemotherapy in this subtype of patients is inferior to its hormone receptor negative counterpart. Several preclinical and clinical studies have suggested that it was growth rate rather than hormone receptor status that determined sensitivity to chemotherapy. In addition, estrogen was proved to recruit more HR+ breast cancer cells into actively dividing phase according to various studies. For premenopausal females, sexual hormone like estradiol fluctuates with menstrual cycle. When menstruation occurs, women have the lowest level of estradiol, which is resemble to pharmaceutical effect of endocrine therapy. If chemotherapy is given to females during menstruation, it's almost equal to concurrent use of chemotherapy and endocrine therapy, which is not recommended by guideline. Accordingly, chemotherapy would attain best efficacy applied at the peak of estradiol, because more tumor cells being in actively dividing phase recruited by comparatively high level of estradiol would help cytotoxic agents function better given that majority of chemotherapeutic drugs are cellular phase dependent. We name this rhythmic mode of chemotherapy for premenopausal HR+breast cancer females, giving chemotherapy to patients when estradiol rises and avoiding prescription at menstruation, tidal chemotherapy. It's postulated that tidal chemotherapy would improve efficacy of neoadjuvant chemotherapy for premenopausal HR+breast cancer females, achieve more pathologic complete response and in the long run improve prognosis.

Long-term follow-up for locally advanced and inflammatory breast cancer patients treated with multimodality therapy

PURPOSE

To determine long-term event-free (EFS) and overall survival (OS) for patients with stage III breast cancer treated with combined-modality therapy.

PATIENTS AND METHODS

Between 1980 and 1988, 107 patients with stage III breast cancer were prospectively enrolled for study at the National Cancer Institute and stratified by whether or not they had features of inflammatory breast cancer (IBC). Patients were treated to best response with cyclophosphamide, doxorubicin, methotrexate, fluorouracil, leucovorin, and hormonal synchronization with conjugated estrogens and tamoxifen. Patients with pathologic complete response received definitive radiotherapy to the breast and axilla, whereas patients with residual disease underwent mastectomy, lymph node dissection, and radiotherapy. All patients underwent six additional cycles of adjuvant chemotherapy.

RESULTS

OS and EFS were obtained with a median live patient follow-up time of 16.8 years. The 46 IBC patients had a median OS of 3.8 years and EFS of 2.3 years, compared with 12.2 and 9.0 years, respectively, in stage IIIA breast cancer patients. Fifteen-year OS survival was 20% for IBC versus 50% for stage IIIA patients and 23% for stage IIIB non-IBC. Pathologic response was not associated with improved survival for stage IIIA or IBC patients. Presence of dermal lymphatic invasion did not change the probability of survival in clinical IBC patients.

CONCLUSION

Fifteen-year follow-up of stage IIIA and inflammatory breast cancer is rarely reported; IBC patients have a poor long-term outlook.

Insulin-like growth factor-I and cancer risk

Growth factor pathways are fundamental in normal tissue regulation and development. In many tissues, factors that function in normal growth and development also have important regulatory roles in transformed malignant cells. The insulin-like growth factor (IGF) system is implicated in the regulation of the malignant phenotype by its effects on proliferation, differentiation, and apoptosis. IGF-I has also been linked to malignant transformation. The role of the IGF-I in cancer has been recognized in both experimental and clinical settings, suggesting that the enhancement of growth factor pathways potentially could increase the risk for cancer development. In this paper, the role of IGF-I signaling in tumor regulation, and the impact of IGF-I modulation using growth hormone replacement therapy are discussed.

Value of estrogenic recruitment before chemotherapy: first randomized trial in primary breast cancer

PURPOSE

Several preclinical studies showed that short-term pretreatment of breast cancer cells with estrogens can increase the antitumor efficacy of different cytotoxic drugs. Some early clinical studies in patients with advanced breast cancer did seem to support these findings. Therefore, the efficacy of estrogenic recruitment followed by chemotherapy was compared with that of chemotherapy alone in a randomized phase III study in women with lymph node-positive primary breast cancer.

PATIENTS AND METHODS

Three hundred twenty-eight patients with stage II/IIIA breast cancer who were younger than 66 years of age were randomly allocated to chemotherapy with fluorouracil, doxorubicin, and cyclophosphamide (FAC) or FAC plus pretreatment with ethinyl estradiol (EE(2)). FAC (500, 50, and 500 mg/m(2), respectively) was administered intravenously once every 4 weeks for four cycles. EE(2) (0.5 mg) was administered orally, both 24 hours and immediately preceding FAC chemotherapy.

RESULTS

Patient and tumor characteristics and chemotherapy dosages were comparable in both treatment groups. Of 318 assessable patients, with a median follow-up of 6.8 years, 177 patients had a relapse and 127 died. No significant differences were observed between the two treatment groups with respect to relapse-free, local recurrence-free, and overall survival according to univariate and multivariate analyses adjusted for age, menopausal status, tumor size, grade, number of positive nodes, and steroid-receptor status. The power for the detection of an increase of 50% in the median relapse-free survival was 80%.

CONCLUSION

Estrogenic recruitment of breast cancer cells before FAC chemotherapy did not influence the efficacy of adjuvant chemotherapy in stage II/IIIA breast cancer patients after a follow-up of 6.8 years.

The Role of Hormonal Therapy in Breast Cancer

This review reassesses the role of hormonal therapy in breast cancer specifically the sequential or concurrent use of endocrine therapy and the combined use of chemotherapy with endocrine therapy. In advanced disease the sequential use of hormone therapies is generally recommended rather than the combined use of various hormonal agents, though combination hormonal therapy offers advantages in certain subsets of patients. The efficacy of combined chemo-endocrine therapy is questionable. Chemotherapy with estrogenic recruitment is an attractive but still experimental concept. However, in an adjuvant setting there is evidence that combined chemo-endocrine therapy causes a significant increase in disease-free and/or overall survival, particularly in postmenopausal patients with estrogen receptor(ER)-positive tumors. While hormonal treatment strategies have clearly benefitted from randomized studies, data regarding optimal endocrine therapy are still insufficient.

Induction chemotherapy with versus without hormonal synchronisation in locally advanced breast cancer

Sixty-nine patients with locally advanced breast cancer were given induction chemotherapy with doxorubicin and cyclophosphamide (day 1) followed by methotrexate and 5-Fu (day 8). Thirty-two of these patients were also given tamoxifen (days 2-6) in an attempt to induce a G1 arrest in cancer cells, and oestrogen (days 7-8) to stimulate proliferation and thus induce a synchronized wave of proliferating cells. The induction therapy response rate was 61% in the series as a whole (n = 69), but was found to be significantly better in the group on the tamoxifen/oestrogen synchronization regimen than in the remainder on chemotherapy alone (82% vs. 43%). This difference was particularly marked in the respective receptor-positive subgroups [90% (9/10) vs. 30% (3/10); p < 0.001]. The findings suggest that, in combination with chemotherapy, tamoxifen/oestrogen therapy, given in the sequence outlined here, constitutes a promising regimen for the treatment of locally advanced receptor-positive breast cancer patients.

Chemotherapy with or without estrogenic recruitment in metastatic breast cancer. A randomized trial of the Gruppo Oncologico Nord Ovest (GONO)

BACKGROUND

This phase III study was carried out to verify whether a kinetic recruitment induced with low doses of diethylstilbestrol (DES) could increase the antitumor activity of chemotherapy in patients with advanced breast cancer.

PATIENTS AND METHODS

Two hundred fifty-eight women with metastatic breast cancer were randomized to receive chemotherapy consisting of cyclophosphamide 600 mg/sqm i.v., epidoxorubicin 60 mg/sqm i.v. and fluorouracil 600 mg/ sqm i.v. (CEF) on day 1 or DES-CEF (diethylstilbestrol 1 mg orally days 1-3 CEF on day 4) every 21 days. Patients were treated until progression or, if responsive, for a maximum of 10 courses.

RESULTS

There were no significant differences between the two treatment arms in response rates (51.3% to CEF and 49.6% for DES-CEF); median progression-free survival (9.4 months for CEF and 11 months for DES-CEF group) or median overall survival (17.3 and 20 months for CEF and DES-CEF arms, respectively). Non-hematological toxicities were superimposable in the two arms, while DES-chemotherapy was more myelotoxic.

CONCLUSIONS

This trial confirms that chemotherapy preceded by estrogenic recruitment is still in an experimental phase and that, at present, it has no role in clinical practice. Further research is needed to test the possibility of combining different mitogens in the light of new information about breast cancer cell growth.

Potentiation of antitumor activity of mitomycin C by estradiol: studies of human breast carcinoma xenografts serially transplanted into nude mice

The effect of experimental cancer chemotherapy with mitomycin C (MMC) was studied using three estrogen-receptor (ER)-positive (MCF-7, R-27, and Br-10) and one ER-negative (MX-1) human breast carcinoma xenograft serially transplanted into nude mice, and the effect of estradiol (E2) priming on the antitumor activity of MMC was investigated. Intramuscular injection of E2 at 1 mg/kg changed the ER state and increased the growth fraction detected by flow cytometry, although the growth rate of ER-positive tumors was not effective by E2 priming. MMC suppressed the growth of the four xenografts in a dose-dependent manner. When 1 mg/kg E2 was administered 1 h before MMC treatment, which was given intraperitoneally at a dose of 3 mg/kg, the antitumor activity of MMC was increased in comparison with MMC alone in ER-positive strains, although the effect of MMC on MX-1 was not changed by E2-priming. Priming with E2 at this dose increases the growth fractions of ER-positive breast carcinoma cells, which are sensitive to MMC, resulting in increased antitumor activity of MMC. This E2-primed MMC chemotherapy may be of value in the treatment of ER-positive human breast cancer.

The use of mammography in breast preservation in locally advanced breast cancer

PURPOSE

As the feasibility of breast preservation in locally advanced breast cancer is currently under evaluation, little information is available correlating mammographic changes to chemotherapy with local outcome. To evaluate the role of mammography in selecting candidates with locally advanced breast cancer for conservative local therapy, we analyzed mammographic changes in the breast to induction chemotherapy and correlated the radiologic appearance with pathologic outcome.

METHODS AND MATERIALS

From 1985 through 1993, 91 patients with Stage III breast cancer were enrolled on a multimodality clinical trial using chemohormonal therapy followed by local treatment and maintenance therapy. Induction therapy consisted of cyclophosphamide, doxorubicin, methotrexate,and 5-fluorouracil with hormonal synchronization using tamoxifen and conjugated estrogens. After nine cycles, surgical biopsies of the breast were performed. Through 1988, clinical examination alone directed the site for postinduction biopsy; for patients treated after 1988, mammography, in addition to physical examination, determined the biopsy location. Local treatment was determined by biopsy result. Patients with a pathologic complete response received radiation only to the breast adn regional nodes, while those with pathologically proven residual disease underwent mastectomy and postoperative radiotherapy. Nine additional cycles of maintenance chemotherapy were administered.

RESULTS

Fifty-five of 91 patients (58%) obtained a clinical complete response (CR) to induction chemotherapy. Twenty-eight of the 53 women with a clinical CR had both pre- and postinduction mammograms. Of these 28 women, 9 obtained a pathologic CR and 19 obtained a pathologic partial response (PR). Fifty-five percent of the pathologic complete responders had resolution of mammographic abnormalities on the postinduction mammograms. Sixty-eight percent (13) of the pathologic partial responders had abnormal mammographic findings. The positive predictive value for residual cancer using physical examination was 92%, while the negative predictive value was only 36%. Among patients with a clinical complete response, the positive and negative predictive values for residual cancer using postinduction mammography were 79% and 56%, respectively. Limitations of mammography included uncertain significance of residual microcalcifications and residual masses on postinduction chemotherapy mammograms.

CONCLUSIONS

Although mammography improved the accuracy of noninvasive evaluations in patients with a clinical complete response, pathologic assessment was still required to determine appropriate local therapy. More sensitive imaging modalities or modifications of film-screen mammography may improve noninvasive detection of residual disease following induction chemotherapy.

Primary systemic treatment with weekly doxorubicin monotherapy in women with locally advanced breast cancer; clinical experience and parameters predicting outcome

Sixty-three patients (median age 64 years) with locally advanced breast cancer (T3, T4 and/or N2) were treated with primary 'neoadjuvant' chemotherapy given as weekly doxorubicin monotherapy (14 mg/m2 per dose). Seven patients had solitary distant metastasis at the time of diagnosis. Twenty-eight patients (45%) achieved 'partial response' to primary chemotherapy. Twenty-nine patients (46%) had 'stable disease', and 6 patients (9%) had 'progressive disease' during treatment. Following chemotherapy, 52 patients were subjected to surgery and another 4 patients had surgery performed after radiotherapy. Surgery was considered impossible in only three patients. After a median observation time of 23 months, local recurrences were observed in 2 patients, one with progressive disease and one with stable disease during chemotherapy. Univariate analyses revealed that large tumour size, high histological grade and high mitotic frequency were associated with poor primary response to chemotherapy. Recent studies have demonstrated a correlation between p53-mutations and chemotherapy response.

Alternating chemotherapy regimens for patients with metastatic breast cancer. A pilot study based on tumor marker kinetics. Cancer and Leukemia Group B

BACKGROUND

Chemotherapy is most effective when applied during the biologically active stage of tumor cells. According to the authors' previous tumor marker kinetic study, methotrexate plus 5-fluorouracil (MF) was found to yield either a cytolytic effect in an MF-sensitive tumor cell population or a cytostatic effect in an MF-resistant population. In the latter, the suppressive effect was transient and the biologic activity resumed in one week after MF administration.

METHODS

Based on this marker kinetic study, an alternating chemotherapy program was designed to study its antitumor and side effects. Methotrexate (M) (200 mg/m2) and 5-fluorouracil (F) (500 mg/m2) were administered intravenously on day 1 followed 24 hours later by leucovorin (L) (10 mg/m2 orally every 6 hours for 6 doses). Cyclophosphamide (C) 300 (mg/m2), doxorubicin (A) (50 mg/m2), and vincristine (V) (1 mg/m2) were given on day 8. The MFL/CAV was given every 4 weeks.

RESULTS

Forty-nine patients with metastatic breast cancer were enrolled; 41 were eligible. There were 5 complete and 23 partial remissions, producing a total response rate of 68%. In 15 patients with liver metastases, the response rate was 73% and the median survival 13.7 months, results superior to those previously reported for this subgroup of patients. Side effects were manageable.

CONCLUSIONS

This regimen, which can be given safely in an outpatient setting, yielded encouraging response and survival rates in patients with visceral-dominant disease with poor prognoses.

The results of modified use of chemotherapy for patients with metastatic breast cancer

We investigated whether modifying standard chemotherapy with 5-fluorouracil, doxorubicin and cyclophosphamide (FAC) could improve the outcome of patients with advanced breast carcinoma. We changed the conventional FAC treatment as follows: firstly, we administered oestrogens during the delivery of chemotherapy. Secondly, we administered 5-fluorouracil by continuous infusion. Thirdly, we limited chemotherapy treatment to 12 cycles and did not continue treatment during remissions. We evaluated this modified treatment in 63 patients and compared its results to other treatments results given at this institution. We found that the modified treatment improved the quality of life and survival of premenopausal breast cancer patients.

The effect of systemic therapy on local-regional control in locally advanced breast cancer

One hundred and seven patients with locally advanced breast cancer were prospectively referred for multimodality treatment on protocol using chemohormonal therapy to maximal response followed by local treatment and maintenance therapy. Forty-eight patients (45%) were diagnosed with Stage IIIA disease, 46 (43%) with Stage IIIB inflammatory cancer, and 13 (12%) with Stage IIIB non-inflammatory disease. Induction therapy consisted of cyclophosphamide, doxorubicin, methotrexate, and 5-fluorouracil with hormonal synchronization using tamoxifen and conjugated estrogens. Local treatment was determined by response to chemotherapy. Patients with a clinical parital response underwent mastectomy followed by local-regional radiotherapy while patients with a clinical complete response were biopsied for pathologic correlation. Those with residual disease received mastectomy followed by radiotherapy while those with a pathologic complete response received radiation only to the intact breast and regional nodes. With a median follow-up of 64 months, patients with IIIA disease had a significantly lower local-regional failure rate compared to IIIB inflammatory patients, with the 5-year actuarial local-regional failure rate as only site of first failure 3% for IIIA disease versus 21% for IIIB inflammatory cancer (p = .02), and local-regional failure as any component of first failure 12% versus 36% (p = .01), respectively. When local-regional failure was analyzed by repeat biopsy, 5/31 (16%) patients with a pathologic complete response treated with radiation only developed a local-regional failure versus 2/53 (4%) with residual disease treated with mastectomy and postoperative radiotherapy. The 5-year actuarial local-regional failure rate as first site of failure was 23% for radiation only versus 5% for mastectomy and post-operative radiotherapy (p = .07). The response to chemotherapy did not reliably predict local-regional control. Both relapse-free survival and overall survival were significantly better for IIIA versus IIIB patients; stratification by repeat biopsy did not however, significantly affect either relapse-free or overall survival.

Recent advances in the treatment of breast cancer

Multidisciplinary efforts have defined a number of prognostic factors and newer strategies to improve the outcome of patients with breast cancer. Conservative surgery has led to improved functional and cosmetic results. The development of a number of effective adjuvant regimens has led to improved survival. In patients with stage I disease, several biological characteristics of tumor have been identified that are associated with increased risk of relapse. A multimodality approach to patients with locally advanced disease and inflammatory cancer has resulted in improved survival. A number of hormonal and cytotoxic drug contaminations can palliate metastatic disease, with a small fraction of patients remaining in extended remission. Dose-intensive programs may lead to further improvements in survival of selected patients with this disease.

Kinetic and morphometric responses of heterogeneous populations of NMU-induced rat mammary tumor cells to hormone and antipolyamine therapy in vivo

The present experiments were designed to evaluate in vivo the differential sensitivity of tumor cell subpopulations to hormone and polyamine manipulations using the hormone-responsive N-nitrosomethyl-urea (NMU)-induced rat mammary tumor. NMU tumor bearing rats were randomly assigned to control, ovariectomy, alpha-difluoromethyl-ornithine (DFMO) administration (an inhibitor of polyamine biosynthesis), or combination treatment, and were sacrificed on day 2, 4, or 7. The proportion of different cells was estimated by morphometric analysis and their replicative activities by [3H]-thymidine autoradiography. In tumors of intact rats, the fractions of glandular, myoepithelial, and non-epithelial cells were 85.3 +/- 2.2%, 4.7 +/- 0.7%, and 9.9 +/- 1.9%, respectively. Ovariectomy induced a similar time-dependent decline in the labelling indices of each cell type (from 5% to 1%). It also decreased the fraction of glandular cells (74.9 +/- 4.5%), while increasing the fraction of myoepithelial (8.6 +/- 1.9%) and non-epithelial (16.3 +/- 3.2%) cells. DFMO exerted similar but more modest effects. DFMO-induced tumor regression was also inferior to that observed with ovariectomy. Combined ovariectomy and DFMO induced a faster and greater suppression of all labelling indices than the individual treatments, even though tumor regression was not superior to that produced by ovariectomy alone. Combination treatment also produced more profound morphologic changes, reducing the fraction of glandular cells to 64.4 +/- 3.9% and increasing that of non-epithelial cells to 26.6 +/- 4.4%. Ovariectomy and DFMO reduced height but not width of glandular cells, resulting in a modest decrease in cell volume. The combination treatment, however, significantly suppressed all three parameters.(ABSTRACT TRUNCATED AT 250 WORDS)

Oestrogen potentiates topoisomerase-II-mediated cytotoxicity in an activated subpopulation of human breast cancer cells: implications for cytotoxic drug resistance in solid tumours

Primary resistance to chemotherapeutic agents is a major problem in the management of advanced cancer. By using oestrogen to modulate the topoisomerase II content of T-47D human breast cancer cells, we show here that cell subpopulations resistant to the topoisomerase-II-interactive drug VPI6 (etoposide) can be identified and quantified using single-cell analytical techniques. Immunohistochemical studies reveal topoisomerase II to be present in approximately 10% of control cells compared with 30% of oestrogen-stimulated cells, and this difference is reflected in the proportions of cells exhibiting VPI6-induced cell-cycle delay. This moderate increase in overall cell sensitivity is accompanied by massive enhancement of clonogenic cell kill, suggesting that oestrogen enhances VPI6 cytotoxicity by recruiting a clonogenic cell subpopulation characterized by increased topoisomerase II content. Flow cytometry confirms that the increase in topoisomerase II is localized to an activated G1-phase cell subset. We conclude that (i) single-cell analysis of cellular topoisomerase II content is predictive of VPI6 chemosensitivity; (ii) the existence of resistant tumour-cell subpopulations does not necessarily indicate the presence of phenotypically divergent subclones; and (iii) rational strategies for eliminating tumour resistance may be based on biological manipulation of specific cytotoxic drug targets.

Tamoxifen. A reappraisal of its pharmacodynamic and pharmacokinetic properties, and therapeutic use

Tamoxifen, a non-steroidal antioestrogen, represents a significant advance in treatment of female breast cancer. In trials of tamoxifen as postsurgical adjuvant treatment of early breast cancer, disease-free survival is consistently prolonged, representing an enhanced quality of life in association with tamoxifen's favourable adverse effect profile. Moreover, overview analysis indicates a survival benefit of approximately 20% at 5 years for all women, most clearly evident in women over 50 years, while a survival benefit independent of menopausal, nodal or oestrogen receptor status has been demonstrated in some individual trials. Thus, for postmenopausal women, tamoxifen is clearly optimal adjuvant treatment, although the relative benefit of adjuvant chemotherapy in node-negative patients requires clarification. A survival benefit for women under 50 has not been clearly demonstrated in overview analysis, but is not precluded by these rather limited data, and adjuvant treatment of premenopausal women with tamoxifen may also warrant serious consideration. Response rates to tamoxifen in advanced breast cancer are around 30 to 35%, increasing with patient selection for oestrogen receptor positivity. Tamoxifen must be regarded as first-line endocrine treatment in postmenopausal women, and may represent an alternative to first-line ovarian ablation in premenopausal women. An emergent role in primary therapy of elderly and frail patients with operable disease is apparent. Tamoxifen is also of benefit following surgery in male breast cancer, and may have a role as first-line endocrine treatment. Tamoxifen also has a potential role in other hormone-sensitive malignancies such as pancreatic carcinoma, and in treatment of benign breast disease. Finally, tamoxifen has a place in treatment of male and female infertility. because of adverse effects is rarely necessary. The most frequent adverse effects are related to the drug's anti-oestrogenic activity, and include hot flushes, nausea and/or vomiting, vaginal bleeding or discharge, and menstrual disturbances in premenopausal patients. Thus, tamoxifen continues to play a major role in management of female breast cancer in both early and advanced stages of disease, with a place also in treatment of male breast cancer and of infertility.

Locally advanced breast cancer current status and future directions

Patients described as having locally advanced breast cancer comprise a heterogeneous group of patients with variable clinical presentations. Systematic evaluation of patients with these presentations has been limited, with much of our current understanding based on retrospective reviews. Prospective pilot studies have demonstrated the feasibility of multimodality therapy. However, there have been few well-conducted randomized trials in this setting. Comparison of results among studies is made difficult by the varying eligibility criteria and the way in which the data are reported. The use of common and consistent definitions of operable and inoperable disease is necessary for a more uniform understanding of the therapeutic interventions necessary for a given patient within this broad category of Stage III or locally advanced breast cancer. There are a variety of opportunities for clinical research activities in this group of patients including tests of hormonal recruitment or synchronization, high dose chemotherapy requiring autologous bone marrow transplantation, perioperative or preoperative chemotherapy, and alternating chemotherapy with short course radiotherapy. The integration of clinical information with biological characteristics of the tumor such as cytokinetics, oncogene amplification, and hormone receptors will be an important and necessary focus of future investigation in this disease.

Estrogen priming in advanced breast cancer

The successful treatment of advanced breast cancer has reached a plateau in recent years. Estrogen priming is a new combination therapy involving estrogens, antiestrogens, and chemotherapy that may result in the improvement of treatment responses. This investigational therapy is designed to synchronize cell cycles with estrogens and antiestrogens in order to enhance the activity of cell cycle-specific anticancer drugs. The pharmacological manipulation of cell growth coupled with appropriate antineoplastic agents could result in a new treatment approach for advanced breast cancer. The rationale and current status of estrogen priming are reviewed.

Oestradiol enhances doxorubicin uptake and cytotoxicity in human breast cancer cells (MCF-7)

The cytotoxic effect of doxorubicin on human breast cancer cells (MCF-7) appeared to be correlated with drug concentration, exposure time and cellular uptake of doxorubicin. The effects of short-term stimulation of the growth of MCF-7 cells with 30 pM oestradiol was investigated with respect to the uptake of doxorubicin and cell kill. Culture of MCF-7 cells in steroid hormone-deprived medium resulted in an approx. 90% arrest of the cells in the G0G1-phase of the cell cycle. Growth stimulation with 30 pM oestradiol caused a 3-5-fold increase in the number of cells in S-G2M phase at between 18 and 24 h after administration of oestradiol to the medium. Incubation of oestradiol-stimulated cells with 0.37 microM doxorubicin during both 1 and 6 h resulted in an augmented inhibition of cell growth compared to unstimulated controls. An enhanced cellular uptake of doxorubicin after administration of oestradiol was observed only after an incubation period of 6 h and not of 1 h. These observations suggest that both an increased sensitivity to doxorubicin and an augmented cellular uptake of the drug may underlie the cytotoxic effects of doxorubicin after pretreatment with oestradiol.

Characterisation of VP-16-induced DNA cleavage in oestrogen-stimulated human breast cancer cells

Cycling cells are recognised to be more susceptible than quiescent cells to the cytotoxic action of many commonly used cancer chemotherapeutic agents. We have found that oestrogen stimulation of T-47D human breast cancer cells is accompanied by a two-fold increase in VP-16-induced DNA cleavage as measured by alkaline DNA unwinding, and that this increase in DNA cleavage is accompanied by a corresponding enhancement of drug-induced cytostasis. The enhancement of VP-16-induced DNA cleavage seen with oestrogen exposure is antagonised both by antioestrogen treatment and by cycloheximide, an inhibitor of protein synthesis, but not by the DNA synthesis inhibitor aphidicolin. Increased c-myc protein synthesis is detectable within an hour of oestrogen exposure, while increased VP-16-induced DNA cleavage is detectable within 4h and increased DNA synthesis within 16h. Only small changes in cell-cycle distribution occur with oestrogen stimulation. In the absence of VP-16, oestrogen does not reduce DNA double-strandedness, nor does it induce changes in chromatin structure as measured by alterations in DNA superhelicity or chromatin accessibility. These findings suggest that oestrogen enhances VP-16-induced DNA damage in asynchronously growing G1-phase cells and that this enhancement may be dependent at some point upon de novo protein synthesis. Oestrogen pre-treatment of T-47D human breast cancer cells improves the therapeutic index of VP-16 without the need for cell synchronisation or highly precise drug scheduling.

Chemotherapy with estrogenic recruitment and surgery in locally advanced breast cancer: clinical and cytokinetic results

Thirty-nine patients with locally advanced breast cancer (T3b-4, N1-3 or inflammatory carcinoma) received 3 cycles of induction chemotherapy with estrogenic recruitment before surgery. The therapeutic regimen consisted of diethylstilbestrol (DES) orally on days 1-3, 5-Fluorouracil + Doxorubicin + Cyclophosphamide on day 4 q 21 days (DES-FAC). After surgery 6 additional cycles of chemotherapy (3 DES-FAC alternating with 3 DES-CMF with Methotrexate + F and C as in FAC) were administered. The objective response rate was 71.8% with 15.4% CR, and 56.4% PR; after surgery 36/39 (92.3%) patients were rendered disease-free. So far, 13 of 26 patients in stage IIIb have relapsed (9 of 13 with inflammatory carcinomas). Three-year survival and progression-free survival are 60% and 53.5%, respectively. Twenty-three of the 39 patients were subjected to serial tumor biopsies during the first DES-FAC regimen to allow for tumor-cell kinetic studies during DES and chemotherapy. A significant estrogenic recruitment occurred in 16 patients (69.6%), irrespective of estrogen-receptor status. At surgery, 3-4 weeks after induction chemotherapy, tumor proliferative activity was significantly depressed in comparison to basal values. These results indicate that breast cancer cells can be recruited in vivo with DES and that chemotherapy following estrogenic stimulation is effective and feasible with acceptable toxicity.

8th San Antonio Breast Cancer Symposium--Plenary lecture. Autocrine and paracrine growth regulation of human breast cancer

We consider the hypothesis that estrogen control of hormone dependent breast cancer is mediated by autocrine and paracrine growth factors secreted by the breast cancer cells themselves. Though we show direct, unmediated effects of estrogen on specific cell functions, we also provide evidence that human breast cancer cells secrete a collection of growth factors (IGF-I, TGF alpha, TGF beta, a PDGF-like competency factor, and at least one new epithelial colony stimulating factor). Some of these are estrogen-regulated in hormone dependent cells, and are constitutively increased in cells which acquire independence either spontaneously or by ras transfection. Collectively, the secreted growth factors are capable of promoting tumor formation by MCF-7 cells in nude mice, though not to the same extent as estrogens. There would seem to be potential for clinical intervention in the autocrine and paracrine control of breast cancer cells, including some cells which are no longer dependent on estrogens.

Autocrine and paracrine growth regulation of human breast cancer

Previous work from our laboratory has demonstrated that human breast cancer (BC) cells in culture can be stimulated by physiologic concentrations of estrogen. In an effort to further understand this process, we have examined the biochemical and biological properties of proteins secreted by human BC cells in vitro. We have developed a defined medium system which simultaneously allows the collection of factors secreted by the BC cells, facilitates their purification and allows for an unequivocal assay of their effect on other BC cells. By both biochemical and radioimmunoassay procedures, MCF-7 cells secrete large quantities of IGF-I-like activity. The cells contain receptors for IGF-I and are stimulated by physiologic concentrations of IGF-I. Multiple additional peaks of growth stimulatory activity can be obtained by partial purification of conditioned media from human BC cells by sequential dialysis, acid extraction and Biogel P60 chromatography. These peaks are induced up to 200-fold by physiologic concentrations of estrogen. Several of these peaks cross-react in a radioreceptor assay with EGF and are thus candidates for transforming growth factors. Monoclonal antibodies (MCA) have been prepared which react with secreted proteins from the MCF-7 cells. One of these MCAs binds to material from MCF-7 and ZR-75-1 hormone-dependent BC cells only when these two lines are treated with estrogen but reacts with conditioned medium from several other hormone-independent cell lines in the absence of estrogen stimulation. This MCA is currently undergoing further characterization and evaluation of its biological potency. We conclude that with estrogen stimulation, hormone-dependent human BC cells secrete peptides which when partially purified can replace estrogen as a mitogen. Their role as autocrine or paracrine growth factors and their effects on surrounding nonneoplastic stroma may suggest a means of interfering with tumor proliferation.

A randomized trial of chemotherapy and hormonal therapy in advanced breast cancer

We randomized 81 postmenopausal women with advanced breast cancer, whose tumors were rich in estrogen receptors or of unknown estrogen-receptor status, to receive either estrogen therapy alone or estrogen therapy combined with chemotherapy. An additional 31 patients, whose tumors were poor in estrogen receptors, were randomized to receive either chemotherapy alone or estrogen combined with chemotherapy. The median duration of follow-up was 87 months. In the receptor-rich group, the survival of the 21 patients receiving combined therapy was significantly longer than that of 19 patients receiving estrogen as initial therapy (followed by chemotherapy after failure or relapse). The median survivals were 72 and 29 months, respectively (P = 0.05 by the generalized Wilcoxon method). Among 41 patients with tumors of unknown receptor status, a survival advantage from combined therapy over chemotherapy was seen in the first two years and then disappeared. The survival in 31 patients with receptor-poor tumors was uniformly short regardless of the therapeutic method. We conclude that combined therapy offers a survival advantage in postmenopausal patients with receptor-rich tumors.