Adjuvant therapy of premenopausal and menopausal high-risk breast cancer patients. Present status of the Danish Breast Cancer Cooperative Group Trials 77-B and 82-B

From September 1977 to November 1987 high-risk (i.e. with positive axillary lymph nodes, or tumor size greater than 5 cm or skin/facia invasion) premenopausal and menopausal breast cancer patients have been included in 2 randomized trials. In both trials the primary surgical treatment was total mastectomy with axillary sampling. In the first trial (DBCG 77-B) 1034 patients all received postoperative radiotherapy (RT) and were further randomized to 1) no systemic treatment (0), 2) cyclophosphamide (C), or 3) cyclophosphamide + methotrexate + 5-fluorouracil (CMF). The chemotherapy was given for 1 year. With a median observation time of 7 years the actuarial survival after 9 years is 50, 60 and 65% respectively. Retrospectively, the survival benefit was observed to be most pronounced in patients with tumor size less than or equal to 5 cm and with less than or equal to 3 positive lymph nodes. In the subsequent study initiated in 1982 (82-B) all patients received CMF for 9 months. Furthermore they were randomized to 1) RT, 2) no further treatment, or 3) tamoxifen (TAM) for 1 year. As of November 1, 1987, 1308 patients have been included. At 4 years and with a median observation time of 2 years the survival is similar in the 3 groups. In conclusion, in high-risk premenopausal and menopausal patients adjuvant chemotherapy combined with RT resulted in a 20-30% relative reduction in mortality at 9 years compared with RT alone. Preliminary analysis of adjuvant CMF + RT, compared with CMF alone or with CMF + TAM, shows after a median observation time of more than 2 years no significant survival differences.

Adjuvant treatment of postmenopausal patients with high risk primary breast cancer. Results from the Danish adjuvant trials DBCG 77 C and DBCG 82 C

The efficacy of adjuvant treatment with tamoxifen was evaluated in protocol DBCG 77 C. Postmenopausal high risk patients (tumor greater than 5 cm, positive axillary nodes, or invasion to skin/fascia) were randomized after total mastectomy and axillary sampling to postoperative radiotherapy (control) or to radiotherapy plus treatment with tamoxifen (TAM), 30 mg daily for 1 year. A total of 1,716 patients entered the study. At 8 years of follow-up, (7 years median time of observation), we observed a significant increase of recurrence-free survival for the TAM treated group and a reduction in mortality, which is significant for patients less than 70 years of age. Retrospectively, an increased recurrence-free survival in TAM treated patients was significant in the following subgroups: tumor less than 5 cm, positive lymph nodes, anaplasia grade II and estrogen receptor level greater than 100 fmol/mg cytosol protein. In the subsequent trial (DBCG 82 C), 1,347 postmenopausal patients less than 70 years were randomized to one of the following 3 regimens: radiotherapy + tamoxifen, 30 mg daily for 1 year (TAM), TAM alone, or TAM + CMF (CMF i.v. day 1 every 4 weeks x 9). The survival is similar in the 3 groups at 4 years (2 years median time of observation).

Stage and pattern of metastases in patients with breast cancer

This study compares the pattern of metastases in 228 patients with initial stage I and 635 patients with initial stage II breast cancer. All these patients had recurrence within a median time of follow-up of 4.9 years (range 2.0-7.0 years). All patients were initially mastectomized, and staging was based on histopathological evaluation of mastectomy specimens. Patients with stage II disease received postoperative radiotherapy; 67% also received systemic adjuvant therapy. Locoregional recurrences were the most common sites of recurrence in stage I, whereas distant metastases occurred more often in stage II patients. Stage II patients had a significantly higher number of metastatic sites than stage I patients. Among patients with a single site of recurrence the frequency of local or regional recurrence was 62% in stage I patients compared to 16% in stage II patients. When correcting for this difference, which was ascribed to the effect of radiotherapy, the number and the distribution of metastatic sites were almost equal in stage I and II patients. The anatomical distribution of metastatic sites in different periods after mastectomy was almost the same in stage I and stage II patients; extraregional lymph node metastases, however, occurred earlier in stage II than in stage I patients. The recurrence-free interval, the survival after recurrence (SAR), and the overall survival were all significantly shorter for stage II than for stage I patients. The reduced SAR for patients with stage II disease hints that tumours of higher stages have a higher rate of progression. The progression time, however, was of the same duration in patients with initial stage I and II breast cancer. The prognostic significance of the classification of patients with breast cancer according to stage does not seem to discriminate tumours with different biological properties with regard to the rate as well as the pattern of dissemination. Postmastectomy follow-up of patients with stage I and II disease should therefore, follow the same guide-lines. Since the anatomical distribution of metastases was the same in different periods after mastectomy, the screening for recurrent disease should not be directed towards any specific sites in certain periods after initial diagnosis.

Evidence of a castration-mediated effect of adjuvant cytotoxic chemotherapy in premenopausal breast cancer

This prospective randomized trial, conducted by the Danish Breast Cancer Cooperative Group, is the largest study, so far, of adjuvant chemotherapy in premenopausal breast cancer. The trial is unique in that it is nationwide and based on a nonselected population of patients, and is the only adjuvant trial studying the effect of cyclophosphamide monotherapy. After total mastectomy with axillary node sampling, followed by local radiotherapy, 1,032 pre- and perimenopausal women with operable breast cancer were randomized to observation alone, or to adjuvant chemotherapy for 1 year with either cyclophosphamide monotherapy or with a combination of cyclophosphamide, methotrexate, and 5-fluorouracil (CMF). As of January 1987, median follow-up was 68 months. From early on both cyclophosphamide alone and CMF were found to improve recurrence-free survival (RFS) significantly and to a similar degree (P = .0001). However, an overall survival advantage did not become evident until 5 years after the start of treatment. So far, this advantage appears to be more pronounced in CMF (P = .0065) than in cyclophosphamide-only patients (P = .08). Thus, the study confirms the findings of the National Surgical Adjuvant Breast Project (NSABP) and Milan trials that adjuvant chemotherapy prolongs the survival of premenopausal women with early breast cancer. A retrospective analysis revealed that, in contrast with CMF, cyclophosphamide alone did not improve RFS significantly in subsets of patients without amenorrhea, with estrogen-receptor (ER) negative tumors, and with tumors of low histological differentiation. Assuming that cyclophosphamide alone is a less tumoricidal treatment than CMF, these findings suggest that the effect of adjuvant cytotoxic chemotherapy is mediated partly through chemical castration, and partly through a purely cytotoxic effect.

Bone metastases in primary operable breast cancer. The role of a yearly scintigraphy

In 231 patients with primary operable breast cancer bone scintigraphies were performed yearly from the second to the 6th year until recurrence irrespective of localization was diagnosed, another cancer was detected, or the patient refused further follow-up or died. During the observation period (from 2 up to 7 years after surgery) 13 patients (5.6%) had bone metastases verified by X-ray or histology within 12 months after the last bone scintigraphy. The scintigraphy was positive in only 7 of these patients. The yearly incidence of bone metastases varied between 0.6 and 2.6%. Due to this low incidence and a low cost/benefit, we conclude that a fixed schedule of repeated scintigraphies in primary operable breast cancer patients otherwise free of apparent disease is not justified.

Prognostic usefulness of estrogen receptor immunocytochemical assays for human breast cancer

Breast cancers of postmenopausal patients at high risk for recurrence participating in an adjuvant therapy protocol were independently assayed for estrogen receptor by conventional dextran-coated charcoal steroid binding assays and by immunocytochemistry (ER-ICA) to compare the two assays and to assess the prognostic usefulness of ER-ICA. The ER-ICA was based on a monoclonal antibody to the estrogen receptor and was applied to lightly fixed, frozen sections of the cancers. Excellent agreement was found between the two estrogen receptor methods. It was found that a combination of the distribution of ER-ICA stained cells and the overall staining intensity gave a statistically significant correlation with the quantitative estrogen receptor dextran-coated charcoal steroid binding assay value. In addition, the overall appraisal of the lesion as ER-ICA positive or negative as well as the ER-ICA staining intensity and proportion of ER-ICA stained cancer cells related to patient disease-free interval and survival, independent of patient lymph node involvement. This relationship of ER-ICA status to prognosis appeared not to relate only to responses to adjuvant tamoxifen treatment since it also was observed with patients who did not receive the antiestrogen.

Pattern of metastases in human breast carcinoma in relation to estrogen receptor status

The distribution of metastases at the first recurrence of breast cancer was studied in 57 estrogen receptor (ER) positive and in 23 ER negative patients, who constituted a subset of 460 patients with operable breast cancer. The pattern of metastases with respect to localization of metastases and the dominant site of first recurrence was similar in patients with ER positive and ER negative tumours. The recurrence-free survival (RFS) and the overall survival were associated with the ER status in the 460 patients. ER positive patients had both a significantly longer RFS (p = 0.0024) and survival (p = 0.0001) compared to ER negative patients. Survival after recurrence was prolonged in patients with soft tissue recurrences only, and the proportion of dead patients was highest in receptor negative patients with metastases to bone and viscera. In conclusion, we could not demonstrate that ER positive and negative tumours have a propensity for recurrence at specific sites.

Argyrophilic cells in 202 human mucinous breast carcinomas. Relation to histopathologic and clinical factors

Two hundred two human, mucinous breast carcinomas were investigated for the presence of argyrophilic granules, and these granules were found in 25% of the cases. The granules were located in the cytoplasm and were heterogeneously distributed within the tumors. Tumors with granules were otherwise morphologically indistinguishable from those tumors without granules. The recurrence-free survival was independent of the presence of granules, and no relation was found to other clinical or histopathologic factors. Tumors with granules were found to be estrogen-receptor positive, and they appear to have a slightly less aggressive growth pattern than tumors without granules, but the difference is far from being statistically significant. It is concluded that there is no convincing evidence that this group of primary breast carcinomas with argyrophilia originates from APUD cells.

Beneficial effect of adjuvant tamoxifen therapy in primary breast cancer patients with high oestrogen receptor values

Oestrogen receptor concentrations were measured in primary tumours of 291 postmenopausal breast cancer patients with high risk of recurrence. These patients were a subset of the 1650 patients participating in the Danish Breast Cancer Cooperative Group's trial of adjuvant treatment with tamoxifen (30 mg daily for one year). A cut-off point of 10 fmol/mg cytosol protein and the use of a Cox proportional hazards model distinguished between patients with long recurrence-free survivals and those with early recurrent disease. The use of this model also showed that patients with an oestrogen-receptor content below 100 fmol/mg did not benefit from the endocrine therapy, while those with concentrations above 100 fmol/mg had a significantly longer recurrence-free survival. This finding is consistent with the response of advanced breast cancer to endocrine treatment.

Bone metastases in primary operable breast cancer. The role of serial scintigraphy

In 1978 and 1979, 1060 Danish patients with primary operable breast cancer were bone-scanned for osseous metastases before entering a nationwide therapeutical trial. A re-reading group interpreted the scans produced in 12 participating hospitals. As a consequence standardized guide-lines for interpretation were agreed upon from 1979. The frequency of positive bone scans suggesting bone metastases fell abruptly from 1978 to 1979, as read both locally and by the re-reading group. As measured statistically the difference between the interpretation of the local and the re-reading groups remained unchanged. Of the 1060 patients 760 were followed by repeated pre-scheduled scans 6 and 12 months after surgery until any kind of recurrence was diagnosed. Only 37 of the 760 patients (4.9%) developed bone metastases verified by radiology or autopsy during the first 2 yr after surgery. A single positive scan, especially performed 6 or 12 months after surgery, as well as two or three scans repeatedly staying or becoming positive increase significantly the risk of developing bone metastases within 12 months after the latest scan. In 13 of the 37 patients with otherwise subsequently proven bone metastases the latest scan(s) were negative. It is concluded that a fixed schedule of repeated bone scans in patients with breast cancer is not warranted.

Prognostic significance of residual cancer tissue after diagnostic biopsy in breast carcinoma. Three-year short-term results

Among 3264 cases of breast carcinoma undergoing diagnostic biopsy and frozen section followed by one-stage mastectomy, the occurrence of residual cancer tissue (RCT) was evaluated as part of a prospective, nationwide trial in Denmark. RCT was defined by the presence of cancer left in relation to the biopsy cavity in the mastectomy specimen. A significantly higher cumulative recurrence rate within 3 yr was found in cases with residual cancer compared to cases without this finding. The difference was most pronounced in the premenopausal high-risk group. Therefore, RCT in the wall of the biopsy cavity is considered a prognostic hazard by itself.

Antiestrogen treatment of postmenopausal women with primary high risk breast cancer

The role of antiestrogen treatment in high risk postmenopausal patients with primary breast cancer is currently evaluated in a nationwide, prospective randomized trial conducted by the Danish Breast Cancer Cooperative Group. The primary treatment is total mastectomy and radiotherapy. As of February 1, 1982, 720 women were randomized to treatment with tamoxifen (30 mg daily for 1 year) and 691 women were randomized to no further therapy. Life-table analysis after 36 months shows a difference in recurrence rates of 9% (p = 0.19) in favor of the tamoxifen-treated patients. The material has been analyzed with respect to established prognostic factors such as age, degree of anaplasia, tumor size, and number of positive nodes. The rates of recurrent disease are lower in all subsets of patients treated with tamoxifen, but are only statistically significant in patients 50-59 years of age or with 4 or more positive lymph nodes. Regardless of treatment, ER negative patients have a 23% higher recurrence rate than ER positive patients after 18 months of analysis (p = 0.0033); this represents an approximate doubling of risk, and is independent of age, degree of anaplasia, tumor size, or lymph node status. With regard to PgR status, there is 11% higher recurrence rate in the PgR negative than in the PgR positive patients (p = 0.097).

Adjuvant chemotherapy with cyclophosphamide or CMF in premenopausal women with stage II breast cancer

After total mastectomy and partial axillary dissection, 805 premenopausal women with stage II breast cancer were randomized to receive postoperative radiotherapy (RT) alone, RT + cyclophosphamide (C) for 12 monthly cycles, or RT + cyclophosphamide/methotrexate/5-fluorouracil (CMF) for 12 monthly cycles. At 3 years actuarial relapse-free survival for RT + C and RT + CMF was significantly better than for RT alone (p = 0.0009 and 0.0001, respectively). There was no significant difference in relapse-free survival between RT + C and RT + CMF. C resulted in more pronounced haematologic toxicity and a higher frequency of amenorrhoea and of alopecia than CMF, while CMF resulted in more pronounced nausea and stomatitis than C. In the preliminary results, C alone may be as effective as CMF in prolonging relapse-free survival in premenopausal women with stage II breast cancer.

What do early bone scans tell about breast cancer patients?

In 1978, 1012 out of a total of 1888 Danish breast cancer patients registered for a nationwide therapeutical trial were bone-scanned to find osseous metastases. A re-reading group (N.R., O.M. and S.P.N.) interpreted 842 of the scans produced in the twelve participating hospitals. Specific criteria were used for grading the scintiscans. Of the 842 scans 682 were performed within 30 days of the operation and were defined as initial. The re-reading group found 50 (7%) of these scans to be equivocal and 46 (7%) to be indicative of bone metastases at the time of operation. The number of X-ray-verified bone metastases was only 5 (0.6%). The frequency of positive bone scans correlated with the age of the patients and tumor size, but not with clinical staging at the time of operation, number of positive axillary lymph nodes or degree of tumor anaplasia. Recurrences and death rates during a 2-yr follow-Up period correlated significantly with initial clinical staging. In the clinical low-risk group a positive initial bone scan worsened the prognosis, but this was not statistically significant for all patients grouped together. Although the prognostic value of the initial bone scan per se is dubious, it serves as a guidance for elective X-ray examination and as a basis for comparing subsequent scans.

Selection of high risk groups among prognostically favorable patients with breast cancer

In a prospective, nationwide, decentralized breast cancer project conducted by The Danish Breast Cancer Cooperative Group (DBCG) the recurrence rate within the first year after surgery was analysed in relation to tumor anaplasia. One thousand forty-eight patients met the requirements of eligibility, i.e. tumor size less than or equal to 5 cm with negative axillary nodes, and no skin or deep invasion. The recurrence rates in tumors with anaplasia Grades I, II, and III were 4, 9, and 14%, respectively (p = 0.001). Therefore, it seems possible, prospectively, among otherwise prognostically favorable patients, to select a group with high risk of recurrence which might benefit from adjuvant systemic therapy.