Stage and pattern of metastases in patients with breast cancer

68Ga-FAPI Outperforms 18F-FDG PET/CT in Identifying Bone Metastasis and Peritoneal Carcinomatosis in a Patient With Metastatic Breast Cancer

A 60-year-old woman, previously treated for breast cancer, was referred to gastroenterologists due to persistent abdominal distension. F-FDG PET/CT revealed multiple abnormal foci at the skeleton including the bilateral ilium, peritoneum, and omentum. Ga-FAPI PET/CT was performed for further detecting the primary lesion, which showed a greater number of bone metastases and higher uptake in peritoneal carcinomatoses than F-FDG. Biopsy at the left ilium and omentum indicated metastases from breast cancer. This case highlighted that Ga-FAPI may outperforms F-FDG PET/CT in identifying bone metastasis and peritoneal carcinomatosis.

Recurrence dynamics does not depend on the recurrence site

INTRODUCTION

The dynamics of breast cancer recurrence and death, indicating a bimodal hazard rate pattern, has been confirmed in various databases. A few explanations have been suggested to help interpret this finding, assuming that each peak is generated by clustering of similar recurrences and different peaks result from distinct categories of recurrence.

METHODS

The recurrence dynamics was analysed in a series of 1526 patients undergoing conservative surgery at the National Cancer Institute of Milan, Italy, for whom the site of first recurrence was recorded. The study was focused on the first clinically relevant event occurring during the follow up (ie, local recurrence, distant metastasis, contralateral breast cancer, second primary tumour), the dynamics of which was studied by estimating the specific hazard rate.

RESULTS

The hazard rate for any recurrence (including both local and distant disease relapses) displayed a bimodal pattern with a first surge peaking at about 24 months and a second peak at almost 60 months. The same pattern was observed when the whole recurrence risk was split into the risk of local recurrence and the risk of distant metastasis. However, the hazard rate curves for both contralateral breast tumours and second primary tumours revealed a uniform course at an almost constant level. When patients with distant metastases were grouped by site of recurrence (soft tissue, bone, lung or liver or central nervous system), the corresponding hazard rate curves displayed the typical bimodal pattern with a first peak at about 24 months and a later peak at about 60 months.

CONCLUSIONS

The bimodal dynamics for early stage breast cancer recurrence is again confirmed, providing support to the proposed tumour-dormancy-based model. The recurrence dynamics does not depend on the site of metastasis indicating that the timing of recurrences is generated by factors influencing the metastatic development regardless of the seeded organ. This finding supports the view that the disease course after surgical removal of the primary tumour follows a common pathway with well-defined steps and that the recurrence risk pattern results from inherent features of the metastasis development process, which are apparently attributable to tumour cells.

Diagnosis of Recurrent and Metastatic Disease Using F-18 Fluorodeoxyglucose-Positron Emission Tomography in Breast Cancer

One of the major strengths of F-18 fluorodeoxyglucose-positron emission tomography (FDG-PET) in breast cancer imaging is in the evaluation of patients who have suspected loco-regional recurrence or distant metastasis. In general, FDG-PET is more sensitive than conventional imaging for the detection of recurrent disease. Because of its ability to more accurately stage patients who have advanced breast cancer, FDG-PET has a significant impact on choice of treatment and management in this patient group.

Patients with recurrent breast cancer: does the primary axillary lymph node status predict more aggressive tumor progression?

BACKGROUND

The extent of axillary lymph node involvement represents the foremost important prognostic parameter in primary breast cancer, and, thus, is one of the main determinants for subsequent systemic treatment. Nevertheless, the relevance of the initial axillary lymph node status on survival after disease recurrence is discussed controversially. Persisting prognostic impact after relapse would identify lymph node status as a marker for tumor biology, in contrast to a simply time-dependent phenomenon.

METHOD

Retrospective analysis of 813 patients with locoregional or distant recurrence of primary breast cancer, who were primarily diagnosed with their disease at the I. Frauenklinik, Ludwig-Maximilians-University, Munich, and the University Hospital in Berlin-Charlottenburg, Germany, between 1963 and 2000. To be eligible, patients were required to have been treated for resectable breast cancer free of distant disease at the time of primary diagnosis, and must have undergone systematic axillary lymph node dissection. Patients with unknown tumor size or nodal status were excluded from the study. All data were gathered contemporaneously and compared with original patients files, as well as the local cancer registry, ensuring high quality of data. The median observation time was 60 (standard deviation 44) months.

RESULTS

At time of primary diagnosis, 273 patients (33.6%) were node-negative, while axillary lymph node metastases were detected in 540 patients (66.4%). In univariate analysis tumor size, axillary lymph node status, histopathological grading, hormone receptor status, as well as peritumoral lymphangiosis and haemangiosis carcinomatosa were significantly correlated with survival after relapse (all, P < 0.0001). Kaplan-Meier analysis estimated the median survival time after relapse in node-negative patients to be 42 months (31-52 months, 95% CI), and 20 months in patients with 1-3 axillary lymph node metastases (16-24 months, 95% CI), compared to 13 months in patients with at least 4 involved axillary nodes (12-15 months, 95% CI). Multivariate logistic regression analysis, allowing for tumor size, axillary lymph node status, histopathological grading, presence of lymphangiosis carcinomatosa, relapse site and disease-free interval confirmed all parameters, except of histopathological grading (P = 0.14), as significant, independent risk factors for cancer associated death. Subgroup analyses, accounting for site of relapse and duration of disease-free interval, confirmed primary lymph node status as independent predictor for cancer-associated death after relapse.

CONCLUSION

Lymph node involvement at primary diagnosis of breast cancer patients predicts an unfavorable outcome after first recurrence, independently of the site of relapse and disease-free interval. These observations support the hypothesis that primary lymph node involvement is not a merely time-dependent indicator for tumor progression, but indicates tumors with aggressive biological behavior.

Detection of locoregional and distant recurrences in breast cancer patients by using FDG PET

Cases of recurrence of breast cancer can pose considerable diagnostic and therapeutic challenges for the oncologic team. The prognosis and management decisions are based on knowledge of the true extent of disease. Conventional staging methods, including physical examination, assessment of levels of tumor markers, cross-sectional imaging, and bone scintigraphy, may not reliably demonstrate the extent of disease in all cases. Physical examination and cross-sectional imaging (computed tomography [CT] or magnetic resonance imaging) can be problematic because (a) the sequelae of previous surgery and radiation therapy can be difficult to distinguish from recurrent neoplasms and (b) early metastatic disease (small lesions) can be difficult to distinguish from benign lesions that are too small to characterize. Positron emission tomography (PET) with 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG) can help clarify inconclusive findings from physical examination and cross-sectional imaging. FDG PET is more sensitive than CT in detection of lymphatic spread of disease to locoregional and mediastinal nodes. Metastases at distant sites including the lung, bone, and the liver are also readily detected at FDG PET. FDG PET has been proved accurate in restaging cases of recurrent breast cancer and will likely aid in directing therapy in these cases.

Prognostic significance of an increased number of micrometastatic tumor cells in the bone marrow of patients with first recurrence of breast carcinoma

BACKGROUND

Using cytokeratin (CK) as a histogenetic marker of epithelial tumor cells in the bone marrow of patients with primary breast carcinoma, a subgroup of patients with decreased survival can be identified. This study was designed to evaluate the frequency and prognostic relevance of such cells in patients with recurrent breast carcinoma.

METHODS

Bone marrow aspirates from 65 patients were analyzed immunocytochemically for the presence of CK positive cells. A quantitative immunoassay with monoclonal anti-CK antibody A45-B/B3 was used and 2 x 10(6) bone marrow cells per patient were evaluated. For prognostic evaluation the authors calculated a cutoff value of micrometastatic tumor cells by analogy to classification and regression tree (CART) analysis. Patients were monitored prospectively for a median of 37 months (range, 11-63 months).

RESULTS

Bone marrow micrometastases were present in 5 of 32 patients (16%) with locoregional recurrence and in 24 of 33 patients (73%) with distant recurrence. The bone marrow status yielded no prognostic indication for patients with locoregional recurrence. In contrast, a cutoff value of 2.5 tumor cells per 1 million bone marrow cells analyzed (2.5 x 10(-6) tumor cells) correlated with a significantly different prognosis for women with distant disease. Patients with metastatic disease and a micrometastatic tumor load of > 2.5 x 10(-6) tumor cells survived for a mean of 6 months (95% confidence interval [95% CI], 2.0-9.1) compared with 17 months (95% CI, 11.6-22.0) for patients with < or = 2.5 x 10(-6) tumor cells (P < 0.0001). Multivariate analysis, allowing for hormone receptor status, disease free interval prior to recurrence, manifestation site of metastases, age, and micrometastases in bone marrow, revealed that bone marrow involvement was an independent risk factor, with a hazard ratio of 7.4 (95% CI, 1.6-13.3) for disease-related death.

CONCLUSIONS

An increased number of micrometastases identified in the bone marrow of patients with metastatic breast carcinoma represents an independent prognostic factor that may influence future therapeutic strategies for patients with metastatic breast carcinoma.

The natural history of operable breast cancer after primary treatment

This paper aimed at reviewing information on the natural history of operable breast carcinoma after primary treatment. Breast carcinoma does not appear as a single disease entity, but as a wide variety of clinical manifestations. Primary loco-regional treatment should have a curative aim. However, the probability of early or late relapse increases according to a series of prognostic factors. The axillary node status remains the main prognostic indicator but especially in node-negative patients, an increasing number of additional morphologic and biological prognostic factors can classify patients according to a low, good or high risk categories. The natural history of the disease is influenced by loco-regional treatment as far as loco-regional control is concerned. The risk of relapse after loco-regional treatment alone differs during the first three years according to nodal status and it then tends to decrease and become more homogeneous. Adjuvant systemic therapies can decrease the probability of relapse, mainly in loco-regional but rarely in distant sites, thus limiting the absolute advantage. In any case, most women after primary treatment are not cured and are still carriers of occult disease. A timely diagnosis of first relapse after primary treatment is the direct aim of follow-up. An improvement in survival is only an indirect aim of the follow-up, and depends, if at all, on an anticipated diagnosis of recurrence, on the disease site in which this anticipated diagnosis is feasible and on application of different therapeutic strategies according to disease extension and to disease site. Follow-up could be tailored according to time after primary treatment (with more frequent examinations during the first three years than thereafter) and according to prognostic factors, mainly the axillary nodal status. Follow-up should not be considered as conceptually independent either from primary treatment or from treatment after recurrence. At time of first relapse, a new prognostic evaluation can be based on sites of disease recurrence, ER status at time of diagnosis and the time interval from primary treatment to relapse. Different therapeutic approaches could be planned according to survival expectation, including experimental treatments for patients having a dire prognosis.

Prognostic factors and significance of chemotherapy in patients with recurrent or metastatic transitional cell cancer of the urinary tract

BACKGROUND

Prognostic factors for patients with disseminated transitional cell carcinoma of the urothelium (TCC) has been examined only in patients selected for studies with chemotherapy. This study was performed to determine important prognostic factors in patients with disseminated TCC and evaluate the impact of chemotherapy.

METHODS

The prognostic factors for survival were analyzed in 240 patients with disseminated TCC admitted from 1976 to 1992. Information on prior medical history, baseline variables, and treatment were related to survival after dissemination. Both univariate and multivariate analyses were performed to identify factors of independent importance.

RESULTS

Univariate analyses indicated that performance status; hemoglobin; leukocyte count; platelet count; concentrations of serum creatinine, aspartate aminotransferase, lactate dehydrogenase, and alkaline phosphatase; hydronephrosis; bone metastases; disease extension; and chemotherapy were related significantly to survival. Multivariate analysis demonstrated that a good performance status, a normal alkaline phosphatase concentration, and a normal serum creatinine concentration were independent prognosticators for long survival. When chemotherapy was included in the analysis, it was found to be the most important independent prognostic factor in conjunction with alkaline phosphatase and performance status.

CONCLUSION

This study has established the importance of performance status and alkaline phosphatase as the most important prognostic factors of survival in patients with disseminated TCC regardless of treatment. Chemotherapy was found to be an independent prognostic variable that indicates a possible prolongation of survival in patients receiving chemotherapy.

Differential influence of prognostic factors on the occurrence of metastases at various anatomical sites in human breast cancer

The present study was initiated by data on the anatomical occurrence of metastases from breast cancer. Metastases may occur at various organs, here grouped into ten categories, and simultaneous occurrences at several sites are common. Our aim was to identify and compare risk factors for development of metastases at each site. The influence of the various risk factors for recurrence at one specific site can be modelled as a standard competing risk problem, using well-established survival analysis techniques such as the Cox regression model. Recently a generalization to joint occurrences at more than one site has been proposed. The more general models allow comparison of the differential prognostic influence of various risk factors on recurrence at different sites. We applied these methods to data from the Danish Breast Cancer Cooperative Group on recurrence after breast cancer, and examined the effect of degree of anaplasia, number of positive lymph nodes, size of primary tumour, skin or deep fascial invasion, age of the patient and adjuvant treatment regimen, as possible risk factors. There were no differential effects of type of therapy on recurrence in different sites. However, chemotherapy had a marginally significant positive effect at all sites. Moreover the number of positive lymph nodes was associated with an increased risk of metastases, homogenous across sites, except for brain where an opposing trend was found. Similarly the degree of anaplasia was associated with a somewhat increased risk of metastases, homogenous except for brain. For brain metastases a significantly more pronounced effect of degree of anaplasia was found. Comparison of the results obtained from the two types of models reveals that the new more general models confirm fewer differences between the influence of the prognostic factors than the traditional regression models suggest.

Survival following locoregional recurrence of breast cancer: univariate and multivariate analysis

Although prognostic variables for locoregional recurrence of breast cancer have been evaluated by univariate analysis, multifactorial analysis has not been previously performed. In the present study, survival following chest wall and/or regional lymphatic recurrence was determined in 230 patients with locoregionally recurrent breast cancer without evidence of distant metastases treated at the Radiation Oncology Center, Mallinckrodt Institute of Radiology and affiliated hospitals. Multifactorial analysis demonstrated that the site of recurrences correlated most strongly with overall survival (p = 0.001). The 5-year actuarial overall survival was 44-49% for patients with isolated chest wall, axillary, and internal mammary lymph node recurrence. Patients with either supraclavicular, multiple lymphatic, or concomitant chest wall and lymphatic recurrence had an 21-24% 5-year overall survival. The 5-year disease-free survival was 28-37% for patients with chest wall, axillary, or internal mammary recurrences compared to 4-13% for those with supraclavicular, chest wall and lymphatic, or those with multiple sites of lymphatic recurrence. Disease-free interval from mastectomy to recurrence was also found to be a significant prognostic factor for overall survival (p = 0.005). Fifty percent of patients with a disease-free interval of at least 2 years survived 5 years following locoregional relapse, compared to 35% for those with disease-free interval of less than 2 years. In the subset of patients with small chest wall recurrences (excised or less than 3 cm) and a disease-free interval of at least 2 years, the 5-year overall and disease-free survivals were 67% and 54%, respectively. These results suggest that subsets of patients with locoregional recurrence of breast cancer can survive for long periods of time. The conventional wisdom that chest wall and/or regional nodal recurrence following mastectomy uniformly confers a dismal prognosis is not necessarily true.

Site-specific effect of chemotherapy in patients with breast cancer

The efficacy of cytotoxic therapy in different anatomical sites can be studied by analyzing the anatomical distribution of recurrences following adjuvant therapy or the rate of response according to site of metastasis. Cumulated data from 7 adjuvant studies showed that the relative reduction in the rate of recurrence was 37% for local and regional recurrences versus 25% for distant metastases. There are only sparse and inconclusive data concerning the anatomical pattern of recurrence according to type of adjuvant chemotherapy. Thus, the majority of trials have not demonstrated significant differences in distribution of metastases in patients receiving different types of adjuvant systemic therapy. The available data on the rate of response in relation to metastatic site showed higher response rates in soft tissue metastases (55%), compared to visceral and bone metastases (40%). Cumulated data from 12 trials showed no differences in response rates between different soft tissue lesions (skin, subcutaneous tissue, lymph nodes, breast), or between metastases demonstrated by paraclinical tests (lung, liver, bone). However, there was a tendency for soft tissue lesions to have a higher response rate (55-60%) than visceral and bone metastases (31-44%). The reason for the observed differences is unknown. At the time of diagnosis soft tissue lesions may be smaller (with better blood supply) than visceral lesions. This might increase the likelihood of response, since experimental data show that the response rate is inversely correlated with tumour burden and tumour size. Another explanation is based on the hypothesis of site-specific clonal selection of tumour cells, which differ with respect to sensitivity to cytotoxic agents. However, the observed differences can also be ascribed to methodological errors or differences in assessing response of tumours at specific sites. Thus, the false positive response rate in soft tissue lesions, evaluated by physical examination, is approximately 20% compared with less than 10% in lung lesions evaluated by x-rays.

Metastatic pattern of infiltrating lobular carcinoma of the breast: an autopsy study

We analyzed the autopsy records and autopsy histological slides of 261 patients with breast carcinoma who died at the Institute of Oncology, Ljubljana, from January 1972 to October 1989, with particular attention to the metastatic pattern of infiltrating lobular carcinoma (ILC) which we compared with infiltrating ductal carcinoma (IDC). In 226 of 261 patients who died with metastatic disease there were 25 cases of ILC, 195 cases of IDC, 4 cases of mixed IDC-ILC, and 2 cases of mucinous carcinoma. There was no statistically significant difference in frequency of metastases to common metastatic sites, such as the liver, bone, and pleura, with the exception of the lungs, in which IDC metastases prevailed (P less than 0.006). By contrast, a statistically highly significant prevalence of ILC metastases to the peritoneum/retroperitoneum, hollow viscera, internal genital organs, leptomeninges, and myocardium was found (P values of less than 0.006- less than 10(-6). The metastases to these sites were characterized by diffuse growth of neoplastic cells that infiltrated in a lymphoma or leukemia-like fashion. Such metastases may remain clinically silent for a long time, in spite of their extensiveness. The difference of metastatic pattern between ILC and IDC is insufficiently appreciated in most of the published studies on ILC.

Pattern of spread and progression in relation to the characteristics of the primary tumour in human breast cancer

Characteristics of primary breast tumours were related to the extent of dissemination, the anatomical location of metastases, and the rate of progression in 863 patients with recurrent breast cancer. The following features were examined: tumour laterality, location within the breast, size, invasion of skin or fascia, presence of residual cancer tissue (RCT) in the mastectomy specimen, and number of positive lymph nodes. Increasing tumour size, increasing number of nodes, and the presence of local invasion and RCT were all associated with a short duration of survival both from initial diagnosis and from first recurrence. None of the factors were related to either the extent of dissemination or the rate of progression. Patients who had their primary tumours located in the medial or central part of the breast had an increased incidence of mediastinal and pleural recurrences respectively. Primary tumours greater than 5 cm, invasion of skin or fascia, and presence of RCT were all associated with an increased incidence of local recurrences. In addition, both RCT and fascial invasion were associated with increased occurrence of brain metastases. Most differences were explainable on the basis of local and regional lymphodynamics. Since the status of the features examined here all vary with time from tumour inception, it is suggested that the impact on prognosis is related to variations in tumour age from inception to primary diagnosis rather than to qualitative biological differences.

Effect of psychosocial treatment on survival of patients with metastatic breast cancer

The effect of psychosocial intervention on time of survival of 86 patients with metastatic breast cancer was studied prospectively. The 1 year intervention consisted of weekly supportive group therapy with self-hypnosis for pain. Both the treatment (n = 50) and control groups (n = 36) had routine oncological care. At 10 year follow-up, only 3 of the patients were alive, and death records were obtained for the other 83. Survival from time of randomisation and onset of intervention was a mean 36.6 (SD 37.6) months in the intervention group compared with 18.9 (10.8) months in the control group, a significant difference. Survival plots indicated that divergence in survival began at 20 months after entry, or 8 months after intervention ended.

The value of yearly chest X-ray in patients with stage I breast cancer

In 263 patients with stage I breast cancer, i.e. tumour less than 5 cm in diameter, no invasion of skin and deep fascia, and no involvement of axillary lymph nodes, X-rays of the chest were performed at 6, 12 months and yearly thereafter to the 6th year or until recurrence, another cancer was detected, the patient refused further follow-up or died. Among 1599 examinations, in only 0.25% (four patients) were unsuspected malignant changes observed. Due to this low cost/benefit ratio a fixed routine schedule of repeated chest X-rays in stage I cancer patients, otherwise apparently free of disease, is not justified.

Body size and menopausal status in relation to the pattern of spread in recurrent breast cancer

The prognosis and pattern of spread were related to body size and menopausal status in 863 patients with recurrent breast cancer. These patients were all enrolled in the adjuvant protocols of the Danish Breast Cancer Cooperative Group. The pattern of spread was illustrated by the number of metastases, the anatomical location of recurrence, and the rate of progression. Body size was estimated as height, weight, Quetelet index (QI), and body surface area (BSA). The body size was unassociated with both recurrence-free interval (RFI) and survival after recurrence (SAR). The groups of patients with different body size had both the same number and the same location of metastases. The tumour growth rates were estimated as clinical rates of progression (i.e. the time elapsed from a single distant metastasis until dissemination). The progression rate was unaffected by body size. Postmenopausal patients had a significantly shorter RFI and SAR compared to premenopausal patients. The number of metastatic sites, the anatomical location of metastases, and the rate of progression were similar in pre- and postmenopausal patients. The study could not confirm most findings from the literature which report a poor prognosis for patients with large body size. Moreover, the results do not suggest interactions between body size, menopausal status, and the clinical course of recurrent breast cancer.

Metastatic pattern in recurrent breast cancer. Special reference to intrathoracic recurrences

The anatomical and temporal patterns of recurrence were studied in 401 patients with first recurrence of breast cancer. All patients underwent the same scheduled investigation program: history, physical examination, blood tests, bone scanning, bilateral iliac crest biopsy, radiologic bone survey, chest x-rays, and ultrasound scanning of the liver. The current article focuses on the diagnosis of intrathoracic (ITH) recurrence. Most patients recurred in a single site and 50% of the recurrences were diagnosed within the first 2 years from initial diagnosis. Chest x-ray revealed ITH recurrence in 27% (109 patients), and in 8% the lung, pleura, and/or mediastinum were the only signs of recurrence. Generally, the status of primary demographic, clinical, and pathoanatomical characteristics were not predictive as to the development of ITH recurrence, although patients with pleural recurrences often had centrally located primary tumors, locally advanced disease, and often received adjuvant radiotherapy. Clinical symptoms and signs of ITH recurrence were present in only one third of the patients, and the diagnostic specificity and sensitivity of serum lactate dehydrogenase were only 33% and 85%, respectively. Since ITH recurrences often are silent, and since recurrence in this site may have both prognostic and therapeutical implications, routine chest x-ray is indicated in all patients with first recurrence of breast cancer.

Histological grade and steroid receptor content of primary breast cancer--impact on prognosis and possible modes of action

The clinical course of breast cancer was related to degree of anaplasia (DA) and steroid receptor (SR) content of primary tumours in 743 patients (pts) with clinical recurrence, initially enrolled in the DBCG-77 protocols. The oestrogen receptor (ER) and the progesterone receptor (PgR) content was known in 110 and 67 pts. The recurrence-free interval, survival after recurrence, and the overall survival were all prolonged in patients with well differentiated tumours or with high SR content. The tumour growth rates were estimated as clinical rates of progression (i.e., the time elapsed from a single distant metastasis until dissemination). The progression rate was prolonged in relatively well differentiated as well as in receptor rich tumours. The extent of dissemination, as indicated by the number of metastatic sites, was not associated with either DA or SR content. However, the anatomical distribution of metastases varied with both DA and SR content: signs of poor prognosis (high DA or low SR content) were associated with occurrence of visceral metastases. In contrast, SR rich tumours had a propensity for recurrence in bone. The results suggest that the impact on prognosis of the features examined here includes both variations in growth rate and metastatic pattern.

Adjuvant systemic treatment and the pattern of recurrences in patients with breast cancer

The aim was to analyze the impact of adjuvant systemic treatment (AST) on the anatomical distribution, the number, and the temporal relationship of the first metastases in 635 patients (pts) with breast cancer. These patients participated in the prospective studies of AST of the Danish Breast Cancer Cooperative Group (DBCG) 77-program. All patients had primary high-risk breast cancer (i.e. node positive or local invasion or tumor size greater than 5 cm). The initial treatment was mastectomy with axillary sampling, followed by postoperative radiotherapy. The types of AST and the number of patients with recurrence were: chemotherapy (CT), 134 pts; levamisole (LEV), 96 pts; tamoxifen (TAM), 154 pts. The pattern of recurrence in these patients was compared with the pattern of recurrence in 251 pts who did not receive AST (controls). Although CT reduced the total number of metastatic sites (P = 0.04), the incidence of liver metastases was increased compared to untreated controls (P = 0.02). The median number of metastatic sites was equal in TAM- and LEV-treated pts compared to controls. The incidence of lung metastases was increased in TAM-treated pts (P = 0.03), and LEV-treated pts had a decreased incidence of lymph node (P = 0.01) and pleural recurrences (P = 0.01) compared to controls. The results may suggest that mechanisms of clonal selection during the metastatic process involve differences in sensitivity to antineoplastic treatments of metastases at various anatomical locations.

Assessment and presentation of survival experience in the Danish Breast Cancer Cooperative Group

The purpose of this article is to describe some statistical methods usually applied in articles concerning survival data. Some fundamental concepts for survival data will be described and among others a short review of the statistical theory of Kaplan-Meier plot and log-rank test will be given. The theory will be exemplified using DBCG data with examples of increasing complexity of the statistical models. As an advanced statistical model Cox's regression model for survival data is discussed. This model has been applied in a DBCG article concerning histological malignancy grading of invasive ductal breast carcinoma and the results from this will be brought up to date and discussed.

The pattern of metastases in human breast cancer. Influence of systemic adjuvant therapy and impact on survival

Of the 3,802 patients enrolled in the DBCG 77 protocols, 863 developed clinical recurrence within a median follow-up time of 4.9 years (range 2.0-7.0). More than 69% of these had their first recurrence confined to a single anatomical site and 12% had more than two metastatic sites. The most common sites were bone (35%), lung (23%), skin (22%), and regional lymph nodes (16%). The observation period after first recurrence was 3.6 years (range 0.8-6.4). Survival after recurrence was significantly related both to the location and the number of metastases. Patients who were given adjuvant chemotherapy (n = 134) had significantly fewer metastatic sites and significantly more frequent liver metastases than untreated patients (n = 50). Patients who received adjuvant tamoxifen (n = 154) had the same number of metastatic sites, but more often had lung metastases than untreated patients (n = 201). These results probably reflect that metastases in different anatomical locations differ with respect to sensitivity to antineoplastic treatments.