Five versus more than five years of tamoxifen therapy for breast cancer patients with negative lymph nodes and estrogen receptor-positive tumors

Integration of systemic therapy and radiation therapy for patients with early-stage breast cancer treated with conservative surgery

There is no consensus on the optimal combination of systemic therapy and radiation therapy for patients with early-stage breast cancer treated with conservative surgery. This article reviews prospective and retrospective studies that shed light on this topic. Patients with positive, close, or unknown microscopic margins appear to benefit from relatively early initiation of radiation therapy, whereas those with wider tumor-free margin widths do not. For patients at high risk of distant failure (such as those with = 4 positive axillary nodes), chemotherapy may be more effective when it begins before radiation therapy rather than after. Regimens of concurrent radiation therapy and chemotherapy tend to have higher acute and subacute complication rates than sequential regimens, but the actual rates vary substantially with the exact details of the overall treatment program. There are no data on the impact of the timing of tamoxifen administration on the effectiveness of radiation therapy. Tamoxifen does not appear to increase complication rates relative to the use of radiation therapy alone. Thus, the best way of giving combined-modality therapy is uncertain. Further retrospective and prospective studies to investigate the issues discussed herein should be performed.

Breast-conserving therapy consisting of wide excision, axillary dissection, and radiotherapy for early-stage breast cancer: the experience of the National Shikoku Cancer Center

Four hundred and forty-eight breasts of 443 female patients were treated with breast-conserving therapy (BCT) consisting of wide excision, axillary dissection, and radiotherapy for early-stage breast cancer at the National Shikoku Cancer Center between July 1989 and December 1999. The average age at operation was 48.7 years, and the mean tumor size by palpation was 1.9 cm. Three hundred and twenty cases (71.4%) were pathologically node-negative. During a median follow-up period of 53 months, 13 patients developed local recurrence. The 5-year overall survival and local recurrence rate registered 94.5% and 3.0%, respectively. Age at operation (35 years or younger vs. 36 years or older; P = 0.0184), pathological lymph node status (P = 0.0261), adjuvant chemotherapy (P = 0.0198), and the combination of estrogen receptor (ER) status and adjuvant tamoxifen (TAM) (ER+ and TAM+ vs. ER- or TAM-; P = 0.0136) were statistically significantly associated with local recurrence. Histological margin status associated with local recurrence was marginally significantly (P = 0.0751). The results of multivariate analysis revealed that age at operation, pathological lymph node status, the combination of ER status and adjuvant TAM, and histological margin status were statistically independent predictors for local recurrence. In conclusion, BCT consisting of wide excision, axillary dissection and radiotherapy is useful and effective for patients with early-stage breast cancer.

Selective estrogen-receptor modulators

Tamoxifen is useful for adjuvant treatment of breast cancer and in some women for the prevention of breast cancer. The risk-benefit ratio in regard to the skeleton and perhaps other organ systems may very well be different for postmenopausal versus premenopausal women. In postmenopausal women, tamoxifen (20 mg/d) increased BMD in the spine and perhaps the hip; however, the effect on fracture risk is unclear. Therefore, for postmenopausal women with osteoporosis, consideration should be given to the addition of an agent that is shown to have efficacy against fractures (such as bisphosphonates), even while these women are on tamoxifen. For women at only modest or moderate risk, with bone density above the osteoporosis range (T score above -2.5) and no major fracture history, tamoxifen is probably adequate for 5 years of use. Potentially serious adverse effects include venous thromboembolism, uterine cancer, benign uterine disease, and cataracts. Raloxifene (60 mg/d) protects against vertebral fractures over 4 years in women with osteoporosis, produces small increases in bone mass of the spine, hip, and total body, and reduces bone turnover in postmenopausal women with or without osteoporosis. No significant effect has yet been demonstrated on nonvertebral fractures after 4 years of treatment. Raloxifene has the additional benefit of substantially reducing the risk of ER-positive invasive breast cancer and does not increase the risk of uterine disease. Raloxifene increases the risk of venous thromboembolic disease to the same degree as tamoxifen and estrogen. Therefore, SERMS and estrogens are generally contraindicated in women with a previous history of venous thromboembolism or those who are at significantly increased risk. Raloxifene is probably most useful in women who have osteoporosis (T score = -2.5) or who are at risk (T score less than -1.5 with clinical risk factors) in the middle menopausal period (age 55-65) or in the early menopausal period in women who have no significant hot flashes. At this stage in life, vertebral fractures are common, but hip fractures are not. Therefore, women who take raloxifene can expect a reduction in the likelihood of having a vertebral fracture, and possibly breast cancer. The lack of definitive efficacy against hip fracture is not a major deterrent to use of this agent in this age group because hip fracture risk is very low. Raloxifene might not be the treatment of choice for elderly women who are at particularly high risk of hip fracture.

Adjuvant hormonal therapy

Recently, the guidelines for adjuvant hormonal therapy for primary breast cancer were presented at the National Institute of Health Consensus Development Conference in November 2000 and at the 7th International Conference on Adjuvant Therapy of Primary Breast Cancer in February 2001. Adjuvant hormonal therapy should be offered basically to all patients with tumors expressing estrogen receptor (ER) and/or progesterone receptor (PR), assessed by immunohistochemistry. The consensus statements recommended 5 years of tamoxifen as standard hormonal therapy for both premenopausal and postmenopausal patients with ER and/or PR positive tumors. Ovarian ablation or suppression of ovarian function combined with tamoxifen is a treatment of choice for premenopausal patients with high-risk endocrine-responsive tumors. The selection of hormonal therapies and their combination with chemotherapy should be decided according to the assessment of risk of relapse, side effects, and patients' condition and preference.

Randomized trial of tamoxifen versus tamoxifen plus aminoglutethimide as adjuvant treatment in postmenopausal breast cancer patients with hormone receptor-positive disease: Austrian breast and colorectal cancer study group trial 6

PURPOSE

To determine whether the addition of aminoglutethimide to tamoxifen is able to improve the outcome in postmenopausal patients with hormone receptor-positive, early-stage breast cancer.

PATIENTS AND METHODS

A total of 2,021 postmenopausal women were randomly assigned to receive either tamoxifen for 5 years alone or tamoxifen in combination with aminoglutethimide (500 mg/d) for the first 2 years of treatment. Tamoxifen was administered at 40 mg/d for the first 2 years and at 20 mg/d for 3 years.

RESULTS

All randomized and eligible patients were included in the analysis according to the intention-to-treat principle. After a median follow-up of 5.3 years, the 5-year disease-free survival in the aminoglutethimide plus tamoxifen group was 83.6% versus 83.7% in the monotherapy group (P =.89). The corresponding data for overall survival at 5 years were 91.4% and 91.2%, respectively (P =.74). More patients failed to complete combination treatment (13.7%) because of side effects as compared to tamoxifen alone (5.2%; P =.0001).

CONCLUSION

Aminoglutethimide given for 2 years in addition to tamoxifen for 5 years does not improve the prognosis of postmenopausal patients with receptor-positive, lymph node-negative or lymph node-positive breast cancer.

Effects of tamoxifen on benign breast disease in women at high risk for breast cancer

BACKGROUND

In 1998 the National Surgical Adjuvant Breast and Bowel Project (NSABP) demonstrated that tamoxifen treatment reduced the incidence of both invasive and noninvasive breast cancer in women at high risk for the disease. We examined the effect of tamoxifen treatment on the incidence of benign breast disease and the number of breast biopsies in the same group of women.

METHODS

We examined the medical records of 13 203 women with follow-up who participated in the NSABP Breast Cancer Prevention Trial. Included in this analysis were women who had undergone a breast biopsy and who had histologic diagnoses of adenosis, cyst, duct ectasia, fibrocystic disease, fibroadenoma, fibrosis, hyperplasia, or metaplasia. The relative risk (RR) for each histologic diagnosis was estimated for women who received tamoxifen and for women who received placebo. We also tallied the number of biopsies that women in the placebo and tamoxifen groups underwent.

RESULTS

Overall, tamoxifen treatment reduced the risk of benign breast disease by 28% (RR = 0.72, 95% confidence interval [CI] = 0.65 to 0.79). Tamoxifen therapy resulted in statistically significant reductions in the risk of adenosis (RR = 0.59, 95% CI = 0.47 to 0.73), cyst (RR = 0.66, 95% CI = 0.58 to 0.75), duct ectasia (RR = 0.72, 95% CI = 0.53 to 0.97), fibrocystic disease (RR = 0.67, 95% CI = 0.58 to 0.77), hyperplasia (RR = 0.60, 95% CI = 0.50 to 0.71), and metaplasia (RR = 0.51, 95% CI = 0.41 to 0.62). Tamoxifen therapy also reduced the risk for fibroadenoma (RR = 0.77, 95% CI = 0.56 to 1.04) and fibrosis (RR = 0.86, 95% CI = 0.72 to 1.03). Compared with the placebo group, the tamoxifen group had 29% (95% CI = 23% to 34%) fewer biopsies (1048 versus 1469) and 19% fewer women who underwent a biopsy (811 versus 1019). This resulted in a 29% reduction in the risk of biopsy in women treated with tamoxifen (RR = 0.71, 95% CI = 0.66 to 0.77). This risk reduction occurred predominantly in women younger than 50 years.

CONCLUSION

Women in this study who received tamoxifen, especially younger women (i.e., <50 years), had a reduced incidence of clinically detected benign breast disease and underwent fewer breast biopsies.

A parametric model for long-term follow-up data from phase III breast cancer clinical trials

We propose a parametric version of a univariate gamma frailty model. The proposed model is shown to be flexible enough to model long-term follow-up survival data from breast cancer clinical trials when the treatment effect diminishes as time progresses, a case for which neither the proportional hazards nor proportional odds assumptions are satisfied. The observed information matrix is computed to evaluate the variances of parameter estimates. A simple parametric test statistic to test proportional odds assumption is also constructed. The model is applied to a data set from a phase III clinical trial on breast cancer.

Nonadherence to adjuvant tamoxifen therapy in women with primary breast cancer

PURPOSE

Although clinical trials have clearly demonstrated the benefits of tamoxifen in women with primary breast cancer, little is known about how this drug is actually used in the general population. We sought to estimate adherence and predictors of nonadherence in women starting tamoxifen as adjuvant breast cancer therapy.

PATIENTS AND METHODS

Subjects were age 18 years or older initiating tamoxifen for primary breast cancer and enrolled in New Jersey's Medicaid or Pharmaceutical Assistance to the Aged and Disabled programs during the study period, from 1990 to 1996 (N = 2,378). Main outcome measures were number of days covered by filled prescriptions for tamoxifen in the first year of therapy with the 4 years after tamoxifen initiation for a subset; predictors of good versus poor adherence.

RESULTS

Twenty-three percent of patients missed taking tamoxifen on more than one fifth of days studied, although on average, patients filled prescriptions for tamoxifen for 87% of their first year of treatment. The youngest, oldest, nonwhite, and mastectomy patients had significantly lower rates of adherence; patients who had seen an oncologist before taking tamoxifen had significantly higher rates of adherence. Overall adherence decreased to 50% by year 4 of therapy.

CONCLUSION

The mean level of adherence to tamoxifen is high compared with other chronic medications. However, nearly one fourth of patients may be at risk for inadequate clinical response because of poor adherence. Because of the efficacy of tamoxifen therapy in preventing recurrence and death in women with early-stage breast cancer, further efforts are necessary to identify and prevent suboptimal adherence.

Adjuvant systemic therapy for lymph node-negative breast cancer less than or equal to 1 cm

Routine screening mammography has increased the incidence of stage I breast cancers. Many more women are being diagnosed with lymph node-negative tumors that are less than or equal to 1 cm in greatest diameter. The National Surgical Adjuvant Breast and Bowel Project recently performed a retrospective analysis of 10,302 women participating in one of five clinical trials, including women with lymph node-negative breast cancer. Of these women, 1259 had tumors less than or equal to 1 cm. The analysis of the women with tumors less than or equal to 1 cm revealed an improved relapse-free survival (RFS) if tamoxifen was given after surgery, compared with surgery alone, for women with estrogen receptor (ER)-positive tumors; and for women with ER-negative tumors, RFS was improved by delivering chemotherapy after surgery. The authors suggested that adjuvant systemic therapy should be considered for anyone with an invasive breast cancer, regardless of the size of the tumor. This paper reviews the data presented in that important, historic article, and discusses their conclusions. Also reviewed are the most recent recommendations for treatment of primary breast cancer from the International Consensus Panel that convened at the Seventh International Conference on Adjuvant Therapy of Primary Breast Cancer in St. Gallen, Switzerland. That panel also addressed the issue of adjuvant systemic therapy in women considered to have a minimal or low risk of developing recurrent disease.

Will the experience with tamoxifen in breast cancer help define the role of antiandrogens in prostate cancer?

Breast and prostate cancers are the two predominant hormone-responsive tumours. The use of the antioestrogen tamoxifen in the treatment of breast cancer has evolved over the past 30 y from treatment for advanced breast cancer to prevention. Tamoxifen is currently the endocrine treatment of choice for advanced breast cancer and for adjuvant therapy in a broad spectrum of women whose primary tumours have functional oestrogen receptors. It has also been shown to reduce the incidence of breast cancer in high-risk women. Non-steroidal antiandrogen therapy is used in the treatment of prostate cancer, but its role is still being defined. The clinical development of tamoxifen and that of the antiandrogens are reviewed and parallels are uncovered which provide insight into contemporary and future management of hormone-responsive prostate cancer.Prostate Cancer and Prostatic Diseases (2001) 4, 72-80

Hot flushes

Almost every woman and some men will encounter hot flushes during their lifetime. Despite the prevalence of the symptoms, the pathophysiology of hot flushes remains unknown. A decline in hormone concentrations might lead to alterations in brain neurotransmitters and to instability in the hypothalamic thermoregulatory setpoint. The most effective treatments for hot flushes include oestrogens and progestagens. However, many women and their physicians are reluctant to accept hormonal treatments. Women want non-pharmacological treatments but unfortunately such treatments are not very effective, and non-hormonal drugs are often associated with adverse effects. Results from recent studies showed that selective serotonin reuptake inhibitors and other similar compounds can safely reduce hot flushes. Moreover, the efficacy of these drugs provides new insight into the pathophysiology of hot flushes. In this critical review, we assess knowledge of the epidemiology, pathophysiology, and treatment of hot flushes.

Anastrozole (Arimidex) in clinical practice versus the old 'gold standard', tamoxifen

For the past 25 years, the estrogen antagonist tamoxifen has been considered the 'gold standard' for the treatment of breast cancer, despite certain tolerability issues and the risk of developing resistance. The aromatase inhibitors work by blocking the conversion of androgens to estrogen and were developed for use in patients where ovarian function had ceased (naturally, surgically or pharmacologically). Anastrozole, a third-generation nonsteroidal aromatase inhibitor that is a highly potent and selective inhibitor of the aromatase enzyme, has been shown to be superior to the gold standard tamoxifen for the first-line treatment of postmenopausal women with advanced breast cancer. As second-line therapy, anastrozole has shown superior survival compared with megestrol acetate and is also efficacious as neoadjuvant treatment in postmenopausal women and in combination with goserelin for the treatment of premenopausal women with advanced breast cancer. More recently, the results of the ATAC (anastrozole, tamoxifen, alone or in combination) trial, a large study in 9366 patients, demonstrated that anastrozole was significantly superior to tamoxifen for the treatment of postmenopausal women with early breast cancer, with regards to disease-free survival (p = 0.013) and incidence of contralateral breast cancer (p = 0.007). In addition, anastrozole was shown to be significantly better tolerated than tamoxifen with respect to endometrial cancer (p = 0.02), vaginal bleeding/discharge (p < 0.0001 for both), ischaemic cerebrovascular events (p = 0.0006), thromboembolic events (p = 0.0006) and hot flushes (p < 0.0001), while tamoxifen was associated with significantly less musculoskeletal disorders and fractures than anastrozole (p < 0.0001 for both). This review focuses on both the clinical pharmacology and the clinical data of anastrozole with emphasis on its future applications.

A randomized trial of the effect of a plant-based dietary pattern on additional breast cancer events and survival: the Women's Healthy Eating and Living (WHEL) Study

The Women's Healthy Eating and Living (WHEL) Study is a multisite randomized controlled trial of the effectiveness of a high-vegetable, low-fat diet, aimed at markedly raising circulating carotenoid concentrations from food sources, in reducing additional breast cancer events and early death in women with early-stage invasive breast cancer (within 4 years of diagnosis). The study randomly assigned 3088 such women to an intensive diet intervention or to a comparison group between 1995 and 2000 and is expected to follow them through 2006. Two thirds of these women were under 55 years of age at randomization. This research study has a coordinating center and seven clinical sites. Randomization was stratified by age, stage of tumor and clinical site. A comprehensive intervention program that includes intensive telephone counseling, cooking classes and print materials helps shift the dietary pattern of women in the intervention. Through an innovative telephone counseling program, dietary counselors encourage women in the intervention group to meet the following daily behavioral targets: five vegetable servings, 16 ounces of vegetable juice, three fruit servings, 30 g of fiber and 15-20% energy from fat. Adherence assessments occur at baseline, 6, 12, 24 or 36, 48 and 72 months. These assessments can include dietary intake (repeated 24-hour dietary recalls and food frequency questionnaire), circulating carotenoid concentrations, physical measures and questionnaires about health symptoms, quality of life, personal habits and lifestyle patterns. Outcome assessments are completed by telephone interview every 6 months with medical record verification. We will assess evidence of effectiveness by the length of the breast cancer event-free interval, as well as by overall survival separately in all the women in the study as well as specifically in women under and over the age of 55 years.

A mechanism of drug resistance to tamoxifen in breast cancer

Drug resistance to tamoxifen (Tam) is a significant clinical problem but the mechanism through which this occurs remains elusive. We have developed a number of xenograft models of Tam-stimulated growth that model breast cancer progression using estrogen receptor positive MCF-7 or T47D breast cancer cells. When estrogen-stimulated T47D:E2 tumors are treated long term with Tam, Tam-stimulated tumors develop (T47D:Tam) that are stimulated by both estrogen and Tam. When HER-2/neu status is determined, it is clear that the T47D:Tam tumors express significantly higher levels of HER-2/neu protein by immunohistochemistry and mRNA as measured by real-time RT-PCR. The T47D:Tam tumors also express higher levels of estrogen receptor and progesterone receptor protein than their estrogen-stimulated T47D:E2 counterparts. We compared out results to the MCF-7 model of Tam-stimulated growth. The MCF-7:Tam ST (estrogen- and Tam-stimulated) and MCF-7:Tam LT (estrogen-inhibited, Tam-stimulated) were bilaterally transplanted to account for any mouse to mouse variation and characteristic growth patterns were observed. TUNEL staining was performed on MCF-7:Tam LT treated with either estrogen or Tam and it was concluded that estrogen-inhibited tumor growth was a result of increased apoptosis. Three phases of tumor progression are described that involve increases in HER-2/neu expression, de-regulation of estrogen receptor expression and increases in apoptosis which in concert determine the phenotype of drug resistance to Tam.

Classifying local disease recurrences after breast conservation therapy based on location and histology: new primary tumors have more favorable outcomes than true local disease recurrences

BACKGROUND

To distinguish true local recurrences (TR) from new primary tumors (NP) and to assess whether this distinction has prognostic value in patients who develop ipsilateral breast tumor recurrences (IBTR) after breast-conserving surgery and radiotherapy.

METHODS

Between 1970 and 1994, 1339 patients underwent breast-conserving surgery at The University of Texas M. D. Anderson Cancer Center for ductal carcinoma in situ or invasive carcinoma. Of these patients, 139 (10.4%) had an IBTR as the first site of failure. For the 126 patients with clinical data available for retrospective review, we classified the IBTR as a TR if it was located within 3 cm of the primary tumor bed and was of the same histologic subtype. All other IBTRs were designated NP.

RESULTS

Of the 126 patients, 48 (38%) patients were classified as NP and 78 (62%) as TR. Mean time to disease recurrence was 7.3 years for NP versus 5.6 years for TR (P = 0.0669). The patients with NP had improved 10-year rates of overall survival (NP 77% vs. TR 46%, P = 0.0002), cause-specific survival (NP 83% vs. TR 49%, P = 0.0001), and distant disease-free survival (NP 77% vs. TR 26%, P < 0.0001). Patients with NP more often developed contralateral breast carcinoma (10-year rate: NP 29% vs. TR 8%, P = 0.0043), but were less likely to develop a second local recurrence after salvage treatment of the first IBTR (NP 2% vs. TR 18%, P = 0.008).

CONCLUSIONS

Patients with NP had significantly better survival rates than those with TR, but were more likely to develop contralateral breast carcinoma. Distinguishing new breast carcinomas from local disease recurrences may have importance in therapeutic decisions and chemoprevention strategies. This is because patients with new carcinomas had significantly lower rates of metastasis than those with local disease recurrence, but were more likely to develop contralateral breast carcinomas.

Aromatase inhibitors in breast cancer: an update

BACKGROUND

Tamoxifen has been the endocrine treatment of choice for patients with breast cancer. The development of selective aromatase inhibitors has offered an alternative management approach for patients in whom a hormonal approach is indicated.

METHODS

The authors reviewed reports in which aromatase inhibitors were compared with tamoxifen for the treatment of metastatic disease, as well as information pertinent to their use as adjuvant therapy.

RESULTS

Both nonsteroidal (anastrozole and letrozole) and steroidal (exemestane) aromatase inhibitors for metastatic disease appear to provide superior efficacy and a better toxicity profile in first- and second-line treatment of metastatic disease than tamoxifen. Early results from the ATAC trial suggest anastrozole is superior to tamoxifen for disease-free survival, particularly in receptor-positive patients, and in reducing the incidence of contralateral breast cancer.

CONCLUSIONS

Aromatase inhibitors have important roles in optimal management of postmenopausal patients with hormone-responsive metastases in both the adjuvant and advanced-disease settings.

Tamoxifen, radiation therapy, or both for prevention of ipsilateral breast tumor recurrence after lumpectomy in women with invasive breast cancers of one centimeter or less

PURPOSE

This trial was prompted by uncertainty about the need for breast irradiation after lumpectomy in node-negative women with invasive breast cancers of </= 1 cm, by speculation that tamoxifen (TAM) might be as or more effective than radiation therapy (XRT) in reducing the rate of ipsilateral breast tumor recurrence (IBTR) in such women, and by the thesis that both modalities might be more effective than either alone.

PATIENTS AND METHODS

After lumpectomy, 1,009 women were randomly assigned to TAM (n = 336), XRT and placebo (n = 336), or XRT and TAM (n = 337). Rates of IBTR, distant recurrence, and contralateral breast cancer (CBC) were among the end points for analysis. Cumulative incidence of IBTR and of CBC was computed accounting for competing risks. Results with two-sided P values of.05 or less were statistically significant.

RESULTS

XRT and placebo resulted in a 49% lower hazard rate of IBTR than did TAM alone; XRT and TAM resulted in a 63% lower rate than did XRT and placebo. When compared with TAM alone, XRT plus TAM resulted in an 81% reduction in hazard rate of IBTR. Cumulative incidence of IBTR through 8 years was 16.5% with TAM, 9.3% with XRT and placebo, and 2.8% with XRT and TAM. XRT reduced IBTR below the level achieved with TAM alone, regardless of estrogen receptor (ER) status. Distant treatment failures were infrequent and not significantly different among the groups (P =.28). When TAM-treated women were compared with those who received XRT and placebo, there was a significant reduction in CBC (hazard ratio, 0.45; 95% confidence interval, 0.21 to 0.95; P =.039). Survival in the three groups was 93%, 94%, and 93%, respectively (P =.93).

CONCLUSION

In women with tumors </= 1 cm, IBTR occurs with enough frequency after lumpectomy to justify considering XRT, regardless of tumor ER status, and TAM plus XRT when tumors are ER positive.

Recursive partitioning identifies patients at high and low risk for ipsilateral tumor recurrence after breast-conserving surgery and radiation

PURPOSE

Recursive partitioning analysis (RPA), a method of building decision trees of significant prognostic factors for outcome, was used to determine subgroups at significantly different risk for ipsilateral breast tumor recurrence (IBTR) in early-stage breast cancer.

PATIENTS AND METHODS

Nine hundred twelve women underwent breast-conserving surgery, axillary dissection, and radiation. Systemic therapy was chemotherapy with or without tamoxifen in 32%, tamoxifen in 27%, or none in 41%. RPA was used to create a decision tree according to predictive variables that classify patients by IBTR risk, and the Kaplan-Meier method was used to calculate 10-year risks. Median follow-up was 5.9 years.

RESULTS

Age was the first split in the partition tree. Patients more than 55 years old had a 4% 10-year IBTR, the only further division being use of tamoxifen or not (2% v 5%, P =.03). For patients </= 55 years old, extensive intraductal component (EIC) was the next significant split. For EIC-negative tumors, age </= 35 years and negative margins were associated with a 10-year IBTR of 3%; with close (</= 2 mm) or positive margins, 34%. Patients 36 to 55 years old with estrogen receptor-positive tumors receiving tamoxifen had a risk of IBTR of 5%, but had a 20% risk without tamoxifen.

CONCLUSION

This RPA showed that age </= 55 versus more than 55 years was the most significant factor for IBTR. Patients </= 35 years old had a low risk of IBTR when tumors were EIC-negative with negative margins. EIC was an independent factor for IBTR for ages </= 55 years. Use of tamoxifen was the most significant factor for patients older than 55 years, but it resulted in a greater absolute decrease in risk of IBTR for patients 36 to 55 years old.

Tamoxifen-related uterine carcinosarcomas occur under/after prolonged treatment: report of five cases and review of the literature

The risk of tamoxifen-related endometrial adenocarcinoma is well established with daily dose and treatment duration of adjuvant tamoxifen as risk factors. There have also been in the past years, a few descriptions of uterine nonepithelial malignancies occurring after tamoxifen. We describe five recent cases of uterine carcinosarcomas occurring under/after tamoxifen administered in an adjuvant setting. None of these patients had received prior pelvic radiation therapy. Their median age at the diagnosis of breast cancer was 58 years (41-68), and 69 years (50-84) at the diagnosis of uterine carcinosarcoma. The median length of exposure to tamoxifen was 9 years (5-20), and the median time from the initiation of tamoxifen to the diagnosis of the uterine malignancy (latency period) 9 years (7-20). All patients presented with an advanced stage (IIA-IVA). Our data, together with those of the literature, plead for a causal role of a prolonged exposure to tamoxifen on the subsequent development of uterine carcinosarcoma. The long latency period observed even in patients receiving only 5 years of treatment leads us also to consider a prolonged gynecologic follow-up of the patients.

Morbidity of tamoxifen–perceptions of patients and healthcare professionals

There is little published data comparing patients' and doctors' perceptions of tamoxifen-related morbidity and toxicity, in particular in terms of side-effects which are not medically serious but which disrupt quality of life. We undertook a questionnaire-based study of 210 randomly selected, disease-free pre- and post-menopausal breast cancer patients to assess perceived morbidity whilst taking tamoxifen. We also questioned 143 healthcare professionals, including nurses, GPs and oncologists, on their opinions of tamoxifen-related side-effects. This study suggests that patients experience significant morbidity while taking adjuvant tamoxifen but will tolerate this for the sake of anticipated benefits. Healthcare professionals particularly hospital-based doctors and specialist nurses tend to overestimate the prevalence and severity of tamoxifen-associated symptoms.

American Society of Clinical Oncology technology assessment on the use of aromatase inhibitors as adjuvant therapy for women with hormone receptor-positive breast cancer: status report 2002

OBJECTIVE

To conduct an evidence-based technology assessment to determine whether the routine use of anastrozole or any of the aromatase inhibitors in the adjuvant breast cancer setting is appropriate for broad-based conventional use in clinical practice. POTENTIAL INTERVENTIONS: Anastrozole, letrozole, and exemestane.

OUTCOMES

Outcomes of interest include breast cancer incidence, breast cancer-specific survival, overall survival, and net health benefit.

EVIDENCE

A comprehensive, formal literature review was conducted for relevant topics and is detailed in the text. Testimony was collected from invited experts and interested parties. The American Society of Clinical Oncology (ASCO)-prescribed technology assessment procedure was followed. BENEFITS/HARMS: The ASCO panel recognizes that a woman and her physician's decision regarding adjuvant hormonal therapy is complex and will depend on the importance and weight attributed to information regarding both cancer and non-cancer-related risks and benefits.

CONCLUSION

The panel was influenced by the compelling, extensive, and long-term data available on tamoxifen. Overall, the panel considers the results of the Arimidex (anastrozole) or Tamoxifen Alone or in Combination (ATAC) trial and the extensive supporting data to be very promising but insufficient to change the standard practice at this time (May 2002). A 5-year course of adjuvant tamoxifen remains the standard therapy for women with hormone receptor-positive breast cancer. The panel recommends that physicians discuss the available information with patients, and, in making a decision, acknowledge that treatment approaches can change over time. Individual health care providers and their patients will need to come to their own conclusions, with careful consideration of all of the available data. (Specific questions addressed by the panel are summarized in Appendix 3.)

VALIDATION

The conclusions of the panel were endorsed by the ASCO Health Services Research Committee and the ASCO Board of Directors.

Tamoxifen ("Nolvadex"): a review

Tamoxifen has been used in the management of breast cancer for over 30 years. Since its introduction for the treatment of advanced breast cancer, its indications have increased to include the treatment of early breast cancer, ductal carcinoma in situ, and more recently for breast cancer chemoprevention. Tamoxifen has a good tolerability profile and moreover, unlike many other endocrine therapies, it is efficacious in both pre- and postmenopausal women. It is the combination of efficacy and tolerability that allows tamoxifen to maintain its position as the hormonal treatment of choice for most patients with oestrogen-receptor positive breast cancer. Ongoing studies will provide further information about the optimal duration of tamoxifen therapy and how it compares with the newer aromatase inhibitors.

Tamoxifen and toremifene treatment of breast cancer and risk of subsequent endometrial cancer: a population-based case-control study

A population-based case-control study was performed to evaluate the risk of endometrial cancer related to tamoxifen or toremifene treatment. All patients with breast cancer diagnosis since 1980 in Finland who subsequently developed an endometrial cancer by the end of 1995 and 3 matched controls were identified among the 38,000 breast cancer patients of the Finnish Cancer Registry database. Detailed information on treatment of breast cancer and potential confounders was collected from hospital records. The OR for tamoxifen treatment (59 cases), adjusted for significant cofactors (increased risk associated with obesity, low parity and PR positivity) was 2.9 (95% CI 1.8-4.7). The OR for toremifene (3 cases) was 0.9 (95% CI 0.3-3.9). The OR related to adjuvant tamoxifen treatment reached its maximum 2-5 years after the beginning of treatment (OR 5.1, 95% CI 2.1-13), while the OR for tamoxifen used for palliative treatment of advanced breast cancer was especially high after a lag of over 5 years (OR 9.5, 95% CI 2.5-36). The risk increase due to tamoxifen was slightly higher if the age at initiation was below 55, and risk was more pronounced among patients with well-differentiated endometrial cancer than patients with cancers of clinical grades 2 or 3. According to our results, treatment with tamoxifen increases the risk of endometrial cancer. Due to the rare use of toremifene up to the mid-1990s, the risk assessment concerning it was inconclusive.

Thrombophilia: what's a practitioner to do?

Management of thrombophilia is an ever-changing field as new disorders are described and additional clinical experience accrues. This paper addresses three common management issues in the care of patients with thrombophilia. The first two topics are updates for common but perplexing hypercoagulable states and the last topic introduces a new option for optimal management of oral anticoagulant therapy. Dr. Jacob Rand updates and organizes the approach to patients with antiphospholipid syndrome. This syndrome is a common acquired thrombophilic state, but the diagnosis and treatment of patients remains a challenge. Dr. Rand outlines his diagnostic and treatment strategies based on the current understanding of this complicated syndrome. Dr. Barbara Konkle addresses the special concerns of managing women with thrombophilia. Hematologists are often asked to advise on the risks of hormonal therapy or pregnancy in a woman with a personal or family history of thrombosis or with an abnormal laboratory finding. Dr. Konkle reviews the available data on the risks of hormonal therapy and pregnancy in women with and without known underlying thrombophilic risk factors. In Section III, Dr. Gail Macik will discuss a new approach to warfarin management. Several instruments are now available for home prothrombin time (PT) monitoring. Self-testing and self management of warfarin are slowly emerging as reliable alternatives to traditional provider-based care and Dr. Macik reviews the instruments available and the results of studies that support this new management option.

Side effects of chemotherapy and combined chemohormonal therapy in women with early-stage breast cancer

The decision to receive chemotherapy or chemohormonal therapy involves careful consideration of both the potential benefits and possible risks of therapy. There are substantial short- and long-term side effects from chemotherapy. By convention, short-term side effects include those toxic effects encountered during chemotherapy, while long-term side effects include later complications of treatment arising after the conclusion of adjuvant chemotherapy. These side effects vary, depending on the specific agents used in the adjuvant regimen as well as on the dose used and the duration of treatment. There is also considerable variability in side effect profile across individuals. This review will focus on the short- and long-term toxicity seen with the most commonly used adjuvant chemotherapy and chemohormonal therapy regimens.

Duration of adjuvant tamoxifen therapy

The benefit of using adjuvant tamoxifen to treat breast cancer has been firmly established for patients with estrogen receptor (ER)-positive tumors, regardless of age, lymph node status, or menopausal status. Uncertainty remains, however, regarding the optimal duration of tamoxifen therapy. We reviewed the findings of randomized clinical trials that directly compared alternative treatment durations. Trials comparing short-term adjuvant treatment with tamoxifen (i.e., 1-3 years) with treatments having durations of about 5 years consistently have demonstrated additional benefits stemming from the longer therapy. Trials testing 5 years of treatment with longer durations have, in the aggregate, suggested no additional benefit for the patient. Nevertheless, the number of recurrences reported to date in these trials is not large, and the results of the individual trials are heterogeneous. Furthermore, as a result of tamoxifen's "carryover" effect, duration trials require considerable follow-up before definitive results can be established. Until more definitive data become available, adjuvant treatment with tamoxifen should be limited to 5 years outside the clinical trials setting. Continued accrual of ER-positive patients to ongoing tamoxifen duration trials, including the Adjuvant Tamoxifen Treatment Offer More (aTTom) and Adjuvant Tamoxifen Longer Against Shorter (ATLAS) trials, is appropriate. Alternatively, patients who remain disease free after 5 years of tamoxifen therapy should be encouraged to participate in trials testing crossover to other hormonal interventions, including selective ER modulators or aromatase inhibitors.

Findings from recent National Surgical Adjuvant Breast and Bowel Project adjuvant studies in stage I breast cancer

Before 1989, credible information about the treatment of breast cancer was derived mainly from randomized clinical trials that enrolled women with either metastatic (stage IV); locally advanced (stage III); or primary, operable, axillary lymph node-positive (stage II) disease. This report provides information from six recent National Surgical Adjuvant Breast and Bowel Project (NSABP) trials involving lymph node-negative (stage I) patients. Findings from NSABP B-13 demonstrated, through 14 years of follow-up, improvements in disease-free survival (DFS) and overall survival from methotrexate and fluorouracil (MF), regardless of age, in women with estrogen receptor (ER)-negative tumors. Results from NSABP B-19, which was conducted with similar patients, demonstrated, through 8 years, a greater overall DFS and survival advantage with cyclophosphamide and MF (CMF) than that observed with MF. Findings from NSABP B-23, in which patients similar to those in B-13 and B-19 were randomly assigned to receive CMF plus placebo, CMF plus tamoxifen (TAM), doxorubicin (Adriamycin) and cyclophosphamide (AC) plus placebo, or AC plus TAM, demonstrated no difference in relapse-free survival (RFS) or overall survival among the four groups through 5 years, either for all patients or relative to age. NSABP B-14, which was carried out in women with ER-positive tumors, compared the outcomes of those who received either placebo or TAM. Through 14 years, superior DFS and overall survival advantages, as well as a reduction in contralateral breast cancer, were observed with TAM. No additional benefit resulted from TAM administration beyond 5 years. Findings from NSABP B-20, a second study conducted in patients with ER-positive tumors, showed, after 8 years, both a DFS and an overall survival advantage from TAM plus either MF or CMF over that achieved with TAM alone. A recent meta-analysis in women with negative lymph nodes and either ER-negative or ER-positive tumors of less than or equal to 1 cm in size was conducted using patients from five NSABP trials. After 8 years, the RFS in women with ER-negative tumors was greater in the group treated with surgery and chemotherapy than in those who underwent surgery alone. In women with ER-positive tumors, RFS and overall survival advantages were observed from the addition of chemotherapy to TAM when that treatment regimen was compared with TAM alone. In addition, evidence has been presented from NSABP B-21, a trial evaluating radiation therapy (XRT) and/or TAM for the prevention of ipsilateral breast tumor recurrence (IBTR) after lumpectomy in women with tumors less than or equal to 1 cm. Findings have shown that XRT is superior to TAM and that XRT + TAM is superior to XRT alone for preventing IBTR. The findings demonstrate that chemotherapy and/or hormonal therapy is effective for the management of women with negative axillary lymph nodes and either ER-negative or ER-positive tumors. Because it also has been proven effective in women with tumors less than or equal to 1 cm, such therapy might also be considered in the treatment of that patient population.

Adjuvant chemotherapy with doxorubicin and cyclophosphamide in women with rapidly proliferating node-negative breast cancer

This prospective clinical trial was designed to assess the impact of adjuvant chemotherapy in women with rapidly proliferating node-negative breast cancer. This group has been predicted to have a 5-year disease-free survival (DFS) of 70% without adjuvant chemotherapy. In this study, 449 women with rapidly proliferating breast cancer (91% measured by S-phase fraction and 9% by histochemistry) received adjuvant chemotherapy with doxorubicin/cyclophosphamide (AC) plus tamoxifen for estrogen receptor-positive or progesterone receptor-positive cancer. The 5-year DFS was 90% (+/- 2%) and the 5-year overall survival was 94% (+/- 1%). At a median follow-up of 62 months, the strategy of administering 6 cycles of AC to women with T2 N0 cancer and 3 cycles in those with smaller T1 N0 cancers appeared to eliminate tumor size as a potential prognostic factor. Adjuvant chemotherapy with AC appears effective in reducing recurrence rates for women with rapidly proliferating node-negative breast cancer.

Fulvestrant (Faslodex): current status in the therapy of breast cancer

Fulvestrant (Faslodex, formerly ICI 182,780) is a potent steroidal antiestrogen that mediates its effects by estrogen receptor downregulation. It appears to act as a pure antiestrogen and exhibits none of the negative side effects associated with the partial agonist activity of tamoxifen. It has been shown to be as effective as the oral aromatase inhibitor anastrozole in postmenopausal women with advanced breast cancer who have progressed on prior endocrine therapy, principally tamoxifen. It therefore provides the clinician with an alternative therapeutic strategy following the development of tamoxifen resistance. Fulvestrant might also have potential as a follow-on therapy after tamoxifen in an adjuvant setting and help alleviate some of the concerns surrounding long-term (up to 5 years) tamoxifen therapy.

[Toxic hepatitis associated with tamoxifen use. A case report and literature review]

Tamoxifen is an antiestrogenic drug that acts by binding to the estrogen receptor. The drug is used as a co-adjuvant treatment in advanced breast cancer expressing the oestrogen-receptor protein. Clinical trials of tamoxifen have shown its efficacy in reducing mortality and recurrence rates over a five-year treatment. Cases of tamoxifen-associated hepatotoxicity have been described, including cholestasis with or without cytolysis and steatohepatitis. We report the case of a female patient who developed hepatic alterations while undergoing continuous tamoxifen treatment. We also present an overview of similar cases published to date and comment on the advisability of continuing or suppressing this treatment in patients with hepatotoxicity or after a five-year treatment period.

Raloxifene is associated with less side effects than tamoxifen in women with early breast cancer: a questionnaire study from one physician's practice

OBJECTIVE

Selective estrogen receptor modulators (SERMs) are being used increasingly for the prevention and treatment of breast cancer. The currently available SERMs, tamoxifen and raloxifene, are both associated with antiestrogenic side effects that can be bothersome. However, no data exist on how they compare in this regard. We conducted a retrospective, questionnaire-based study to answer this question.

METHODS

Women with early breast cancer in one physician's practice who had received either or both of these drugs were surveyed using a self-administered questionnaire. Respondents graded the frequency and severity of side effects related to estrogen deprivation, such as vaginal dryness, mood changes, hot flashes, weight gain, and changes in libido, as well as other side effects, such as vaginal discharge. They were separated into three groups for analysis (group 1, tamoxifen only; group 2, raloxifene only; group 3, both drugs). Side effects graded 4 or 5 (or weight gain >10 pounds) were considered severe.

RESULTS

Two hundred sixty-four questionnaires were available for analysis. Women on raloxifene had a shorter average duration of therapy. In comparing the tamoxifen and raloxifene groups, vaginal discharge, severe hot flashes, and weight gain of >10 pounds were significantly more frequent with tamoxifen. However, weight gain was also related to the duration of therapy with either drug.

CONCLUSIONS

In this observational study, antiestrogenic side effects were common with either tamoxifen or raloxifene. Raloxifene is associated with significantly less vaginal discharge and severe hot flashes than tamoxifen in women with early breast cancer. Although weight gain of >10 pounds may also occur less frequently on this drug, this may be confounded by the shorter average duration of raloxifene therapy.

Medical management of breast cancer: today and tomorrow

The medical management of invasive breast cancer has evolved based on the recognition that surgery alone was associated with few long-term cures. This Update will review the current status of breast cancer medical management in three areas: prevention in individuals with an elevated risk, adjuvant (postoperative) treatment of early breast cancer, and treatment principles in metastatic disease. Tamoxifen has emerged as a promising agent in the treatment of women at an increased risk for breast cancer and in those with in situ disease. However, the risks of treatment must be carefully weighed against the benefits in these cohorts of women with an excellent overall prognosis. This same principle can be applied to the use of adjuvant treatment in early invasive breast cancer, where the goal is cure. Adjuvant polychemotherapy is recommended in women considered at high-risk for relapse and death. In addition, women with hormone-sensitive breast cancer are offered adjuvant taxmoxifen. Nonetheless, there are some patients with low-risk disease or those with significant co-morbidities that are unlikely to benefit from adjuvant therapies and likely to sustain toxicities. The treatment goal in metastatic breast cancer is focused on palliation of symptoms as fewer than 10% of such patients achieve 5-year survival. However, novel targeted therapies are changing the treatment armamentarium and hold great promise. These new directions of treatment will be discussed as well as areas of controversy.

Antiaromatase agents: evolving role in adjuvant therapy

The goal of adjuvant hormonal therapy is to prevent breast cancer recurrence. Standard therapy with tamoxifen has shown great value in the adjuvant setting; however, its tolerability profile can render it unsuitable for some patients. The aromatase inactivator, exemestane, and the 2 aromatase inhibitors, letrozole and anastrozole, have been shown to be equivalent or superior to tamoxifen with respect to multiple endpoints in patients with metastatic breast cancer. With tolerability profiles that are similar to, and in many cases, more acceptable than that of tamoxifen, and efficacy potentially superior to tamoxifen, studies using the antiaromatase agents as adjuvant therapy are currently ongoing. These trials will answer some important questions, such as the order in which adjuvant hormonal therapies are selected to maximize efficacy, whether the antiaromatase agents show improved tolerability, and whether combination therapy is more effective than monotherapy.

The value of adjuvant treatment in young women with breast cancer

The postoperative management of breast cancer is an ever-changing field. Young patients, in particular, have attracted recent interest as it has become apparent that age alone is a poor prognostic indicator for breast cancer. Adjuvant therapies indisputably delay breast cancer recurrence and save lives, and should be considered for all young patients. Chemotherapy is increasingly being considered appropriate for all women under the age of 35 years, regardless of other risk factors, but poses the particularly difficult problem of infertility for these young women. As the additional benefits of anthracyclines and taxanes in the adjuvant setting become clear, chemotherapy regimens are also becoming increasingly intensive and the risk of myocardial damage and leukaemia should not be ignored. The benefits of chemotherapy need to be weighed against the possible dangers, and therapy should be individualised according to cancer pathology and patient circumstance. Tamoxifen should be given for 5 years to all women whose cancer is estrogen receptor positive, regardless of whether the patient has received chemotherapy. If chemotherapy is not given, the addition of luteinising hormone-releasing hormone (LHRH) agonists to tamoxifen in patients with estrogen receptor positive breast cancers appears to be beneficial. The addition of LHRH agonists to chemotherapy and tamoxifen is currently being evaluated in randomised trials. Radiotherapy should be given after breast conservation surgery, and should include the axilla if nodes are involved and the axilla has not been surgically cleared. Chest wall radiotherapy should be considered following mastectomy in young women considered at high risk of local recurrence, but the long-term morbidity and mortality of local radiation therapy, which is increased in young women, needs to be considered.

Adjuvant therapy in breast cancer

The new millennium ushers in an exciting time in the treatment of early stage breast cancer. Although worldwide incidence statistics have not changed significantly in the past decade, mortality rates have declined. This change seems to be related to public health initiatives that increase early detection and awareness and to an increase in the efficacy of adjuvant treatments, including advances in chemotherapy and the emergence of biologic treatments. Physicians from many specialties participate in multidisciplinary tumor boards. Moreover, patients, families, and advocacy groups have taken on new responsibilities, offering encouragement and support for clinical and basic research.

Role of antiestrogens and aromatase inhibitors in breast cancer treatment

This review explores the recent experience with, and the basis for, the use of selective estrogen receptor modulators to treat and prevent breast cancer. As new agents are unveiled, they will continue to be tested against tamoxifen. A number of new selective estrogen receptor modulators are in clinical development in an attempt to decrease the unwanted effects of tamoxifen. Raloxifene holds the promise of treating osteoporosis with the beneficial side effect of breast cancer prevention. Additionally, two different classes of hormonal agents, the aromatase inhibitors and estrogen receptor down-regulators, which have no estrogen-like properties at any site, appear to be promising new treatments for advanced breast cancer.

Costs of treatment for elderly women with early-stage breast cancer in fee-for-service settings

PURPOSE

This study provides population-based estimates of the treatment costs for elderly women with early-stage breast cancer, with emphasis on costs of modified radical mastectomy (MRM) compared with breast-conserving surgery (BCS) and radiation therapy (RT).

PATIENTS AND METHODS

Women with breast cancer from the Surveillance, Epidemiology, and End Results cancer registries were linked with their Medicare claims, 1990 through 1998. Each claim was assigned to an initial, continuing, or terminal care phase after a cancer diagnosis. Mean monthly phase-specific costs were determined for all health care and for treatment related only to cancer. Cumulative long-term costs of care that accrue during a women's remaining lifetime were calculated by treatment group.

RESULTS

Initial care costs for the 6 months after diagnosis for women who underwent BCS with RT were approximately $450 per month higher than for women with MRM. During the continuing-care phase, costs for women undergoing BCS with RT were significantly less expensive than for MRM cases. The two groups had similar costs in the terminal-care phase. Assuming the same survival distributions, long-term costs for women undergoing BCS with RT were not statistically different than for women undergoing MRM.

CONCLUSION

Although mastectomy was less costly in the initial phase, the lifetime costs of BCS with RT and mastectomy were equivalent. Thus, women's preferences, resources to cover out-of-pocket costs, and life situations should be the major factors addressed in shared decision making about treatment options.

A rationale for the reinitiation of adjuvant tamoxifen therapy in women receiving fewer than 5 years of therapy

The overview analysis of adjuvant therapy trials in early-stage breast cancer by the Early Breast Cancer Trialists' Collaborative Group (EBCTCG) compared 1, 2, and 5 years of adjuvant therapy. The optimal benefit to patients in terms of reduced risk of recurrence and death was clearly conferred by 5 years of therapy with tamoxifen compared to shorter durations of therapy. Many women with early-stage breast cancer treated in the past received a recommendation for shorter durations of tamoxifen therapy. The obvious question is whether reinitiating tamoxifen to complete a full 5-year course would further reduce the risk of recurrence and death. In an attempt to explore this issue, we have analyzed recurrence rates in women who received different durations of tamoxifen therapy in the adjuvant setting. The data used for this analysis are directly from the EBCTCG. Our analysis suggests that women who received 1-2 years of adjuvant tamoxifen therapy may benefit from reinitiation of tamoxifen to complete a 5-year course.

Selective estrogen receptor modulators: tissue actions and potential for CNS protection

Significant physiologic changes occur during menopause. Evidence exists to suggest that estrogen may be neuroprotective under specific conditions. However, there are limitations in the neuroprotection afforded by standard hormone therapy. Accordingly, alternative agents with selected estrogenic effects may hold even greater promise rather than conventional hormone replacement therapy for the prevention and treatment of CNS injury. Recently, a variety of selective estrogen receptor modulators (SERMs) have been developed to retain the favorable and minimize the adverse side effects of estrogens. This review focuses on the CNS and known neuroprotective effects of two specific SERMs, raloxifene and arzoxifene. Recent studies hint that raloxifene and arzoxifene are neuroprotective and may preserve some elements of cognitive function. However, the mechanism of action is not well described and it is unclear if the beneficial effects of SERMs rely on activation of estrogen receptors.

Tamoxifen and ovarian cysts: a prospective study

PURPOSE

To prospectively follow a group of women with breast cancer on tamoxifen for the development of ovarian cysts.

METHODS

72 women were followed every 6 months with pelvic examination and vaginal ultrasound. Chi square and Student's t-test were used for statistical analysis.

RESULTS

The duration of treatment was 31.5+/-20 months. The mean age was 51.2+/-9.8 years. 55.6% were post-menopausal. Out of 72 women, 18 (25%) developed ovarian cysts. The mean age of women who developed ovarian cysts was significantly lower than in those who did not (47.0+/-7.0 and 52.5+/-10.2 years, respectively, P=0.03), however, the mean duration of treatment was not significantly different (33.3+/-17.4 and 29.3+/-20 months, respectively, P=0.45). Out of 32, 14 (43.8%) pre-menopausal and out of 40, 4 (10%) post-menopausal women developed ovarian cysts (P=0.003). They developed the cysts after an average duration of 33.3+/-18 and 50.7+/-6.2 months, respectively (P=0.7). The average diameter of the cysts was 2.8+/-1.2 cm. All cysts were simple except for one pre-menopausal women. All the cysts in post-menopausal women resolved spontaneously. One pre-menopausal patient had a multi-loculated cyst, was operated and had a serious cystadenoma. In nine patients, the cysts resolved spontaneously and in three after discontinuation of tamoxifen, and one patient was lost to follow-up. All cysts were asymptomatic.

CONCLUSION

Ovarian cysts frequently develop in women with breast cancer on tamoxifen. The majority of the cysts resolve spontaneously, therefore an expectant management with follow-up ultrasonography is recommended.

Adaptive hypersensitivity to estradiol: potential mechanism for secondary hormonal responses in breast cancer patients

Women with hormone dependent breast cancer initially respond to hormone deprivation therapy with tamoxifen or oophorectomy for 12-18 months but later relapse. Upon secondary therapy with aromatase inhibitors, patients often experience further tumor regression. The mechanisms responsible for secondary responses are unknown. We postulated that hormone deprivation induces hypersensitivity to estradiol. Evidence of this phenomenon was provided in a model system involving MCF-7 cells grown in vitro and in xenografts. To determine if the ER transcriptional process is involved in hypersensitivity, we examined the effect of estradiol on ER reporter activity, PgR, PS2, and c-myc as markers and found no alterations in hypersensitive cells. Next, we examined whether MAP kinase may be upregulated in the hypersensitive cells as a reflection of increased growth factor secretion or action. Basal MAP kinase activity was increased both in vitro and in vivo in hypersensitive cells. Proof of principle studies indicated that an increase in MAP kinase activity induced by TGFalpha administration caused a two- to three-fold shift to the left in estradiol dose response curves in wild type cells. Blockade of MAP kinase with PD98059 returned the shifted curve back to baseline. These data suggested that MAP kinase overexpression could induce hypersensitivity. To determine why MAP kinase was increased, we excluded constitutive receptor activity and growth factor secretion by the demonstration that the pure anti-estrogen, ICI 182780, could inhibit MAP kinase activation. We also excluded hypersensitivity to estradiol induced growth factor secretion, and thus MAP kinase activation, since estradiol stimulated MAP kinase at 24, 48, and 72 h at the same concentrations in hypersensitive as in wild type cells. Surprisingly, a series of experiments suggested that MAP kinase increased in hypersensitive cells as a result of estrogen activation via a non-genomic pathway. We examined the classical signal pathway in which SHC is phosphorylated and binds to SOS and GRB-2 to activate Ras, Raf, and MAP kinase. With 5-20 min of exposure, estradiol caused binding of SHC to the estrogen receptor, phosphorylation of SHC, binding of GRB-2 to SOS, and activation of MAP kinase. All of these affects could be blocked by ICI 182780. Taken together, these observations suggest that the cell membrane ER pathway may be responsible for upregulation of MAP kinase and hypersensitivity in cells adapted to estradiol deprivation.

Use of SERMs for the adjuvant therapy of early-stage breast cancer

Tamoxifen was the first in a class of drugs now commonly referred to as selective estrogen receptor modulators or SERMs. SERMs exhibit tissue-specific estrogenic agonist/antagonist activity through their ability to bind to the estrogen receptor alpha (ER) protein and interact with coregulatory proteins, thereby modulating transcription of estrogen target genes. Since its first approval by the United States Food and Drug Administration (FDA) in 1977, tamoxifen has been found to (a) lower the risk of recurrence and death for women with early-stage hormone receptor-positive breast cancer, irrespective of menopausal and node status or use of adjuvant chemotherapy; (b) reduce the risk of invasive breast cancer following breast conservation in women with ductal carcinoma in situ (DCIS); and (c) reduce the risk of breast cancer in high-risk women. Toremifene is the only other SERM approved by the FDA for breast cancer treatment. However, it offers no clear clinical advantage over tamoxifen in the adjuvant or metastatic settings. Several other SERMs are in various phases of clinical development. In addition, strategies to combine SERMs with other endocrine therapy like ovarian suppression or aromatase inhibitors are active areas of investigations. At present, SERMs are recognized as the first targeted and relatively nontoxic medical therapy for women with high-risk or steroid hormone receptor-positive breast cancer.