Abstract S5-2: Iatrogenic Displacement of Tumor Cells to the Sentinel Node after Surgical Excision Biopsy in Primary Breast Cancer

Background: It is shown that isolated tumor cells are more common in the sentinel node after needle biopsy of a breast cancer, indicating iatrogenic displacement of epithelial cells. This may result in unnecessary axillary lymph node dissections. It is possible that a similar iatrogenic displacement occurs after surgical excision biopsy but the incidence and clinical significance is basically unknown.

Material and Methods: By linking data from the Danish Breast Cancer Cooporative Group database and data from the Danish National Health Registry we compared the incidence of isolated tumor cells and micrometastases in the sentinel node of 347 breast cancer patients with prior surgical excision biopsy to a group of 14401 patients without prior surgical excision biopsy in a multivariate analysis adjusting for tumor size, receptor status, type and histological grade. The incidence of isolated tumor cells in the sentinel node was further analysed by histological type. Finally, we investigated the incidence of non-sentinel node metastases in patients with isolated tumor cells and micrometastases in the sentinel node after prior surgical excision biopsy.

Results: We found an adjusted odds ratio on 3.99 (95% CI 2.67-5.97; P<0.0001) for having isolated tumor cells in the sentinel node after surgical excision biopsy. Likewise, we found an adjusted odds ratio for having micrometastases on 1.62 (95% CI 1.20 -2.18; P=0.002). Isolated tumor cells were, in general, more common in the sentinel node of lobular carcinomas compared to ductal carcinomas (adjusted OR 3.51; 95% CI 2.80-4.40; P<0.0001). In contrast, the increase in isolated tumor cells after surgical excision biopsy was especially seen in patients with ductal carcinomas with an adjusted odds ratio on 5.41 (95% CI 3.45-8.48; P=0.054) whereas the odds ratio for lobular carcinomas was only 1.53 (95% CI 0.45-5.14) (P=0.054 for heterogeneity). None of the 20 patients with isolated tumor cells in the sentinel node after prior surgical excision biopsy had non-sentinel node metastases compared to 13% in the group without prior surgical excision biopsy (P=0.15). In patients with micrometastases in the sentinel node after prior surgical excision biopsy 13% had non sentinel node metastases compared to 18% in the group without prior surgical excision biopsy (P=0.29).

Conclusions: The 4-fold increase in isolated tumor cells in the sentinel node after surgical excision biopsy indicates that this procedure induces iatrogenic displacement of epithelial cells. This displacement is more common in ductal carcinomas, despite the fact that lobular carcinomas, in general, are more likely to present with isolated tumor cells in the sentinel node. We found no further dissemination to non-sentinel lymph nodes, suggesting that isolated tumor cells in the sentinel node in these women do not indicate further spread of disease. Hence, in case of isolated tumor cells in the sentinel node after prior surgical excision biopsy, omission of axillary lymph node dissection should be considered.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr S5-2.

Abstract P5-01-08: Preoperative Positron Emission Tomography/Computed Tomography (PET/CT) and 18F-Fluorodeoxyglucose (18F-FDG) Compared with Conventional Assessment in Patients with Early Primary Breast Cancer: Preliminary Results of a Prospective Study

Background: The prognosis and clinical management of patients with newly diagnosed breast cancer depends on the extent of disease. The aim of this study was to compare the diagnostic and therapeutic impact of preoperative PET/CT, using 18F-FDG in the initial extra-axillary staging of patients with early breast cancer, to the results of conventional assessment. One hundred patients are planned enrolled. We here report the results of the first fifty consecutive patients.

Patients and methods: Fifty consecutive patients with newly diagnosed early operable breast cancer with tumors ≥2 cm were examined preoperatively with conventional assessment (mammography, breast/axilla ultrasound, chest x-ray and blood samples) and PET/CT. Conventional assessment and PET/CT were evaluated independently with no prior knowledge of the other. Distant metastases/new primary cancers found on PET/CT were confirmed histologically, by other imaging modalities or with at least 1 year of follow-up.

Results: The mean age was 56 ± 11 years. PET/CT identified primary tumor in all but two patients (96%). Nine cases of extra-axillary lymph node involvement were solely revealed by PET/CT in the internal mammary chain (n=7) and the supraclavicular region (n=2). Additionally, PET/CT solely detected distant metastasis (ovary, bone) in two patients and new primary cancers (ovary, lung) in another two patients. Two patients (4%) had non-malignant focal uptake of 18F-FDG confirmed with histologic biopsies (schwannoma, colon adenoma).

In 12 patients (24%) extra-axillary malignancy was detected by PET/CT only, leading to an upgrade of initial staging in 20% (10/50) of patients and ultimately a modification of planned treatment in 4 (8%) patients. No patient was down staged by PET/CT.

Conclusion: PET/CT is a valuable tool to provide information on extra-axillary lymph node involvement, distant metastases and other occult primary cancers. Preoperative 18F-FDG-PET/CT has a substantially impact on initial staging and on clinical management in patients with early stage breast cancer.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P5-01-08.

Multimodal prevention of pain, nausea and vomiting after breast cancer surgery

BACKGROUND

Despite many one- or two-modal attempts to relieve postoperative nausea and vomiting (PONV) and pain, postoperative issues following breast cancer surgery remain a substantial problem. Therefore, the aim of this explorative, hypothesis-generating study was to evaluate the effect of a multimodal, opiate-sparing, evidence-based regimen for prevention of PONV and pain.

METHODS

Two hundred consecutive patients scheduled for breast cancer surgery were included. The prevention regimen included a package consisting of preoperative paracetamol, dextromethorphan, celecoxib, gabapentin, dexamethasone, total intravenous anaesthesia and intraoperative ondansetron. The patients were prospectively scored according to PONV, pain during rest and mobilization and major side effects.

RESULTS

Of 200 consecutive breast cancer patients, 191 received the full package. During the first 36 postoperative hours, 79.1% reported no PONV at all and only 3.7% reported severe PONV. At rest, 69.6% reported no or light pain and 3.1% reported severe pain, with corresponding values of 59.7% and 8.9% during arm mobilization. Mean postoperative morphine consumption was 2.2 mg. The only significant side effect was transient dizziness.

CONCLUSION

A multimodal, opiate-sparing regimen to prevent pain and PONV seems to be more effective than one- or two-component regimens on PONV and pain after breast cancer surgery, a result which calls for large-scale multi-center or randomized studies.

[The significance of reproductive history for prognosis of primary breast cancer]

The aetiological impact of a woman's reproductive history on breast cancer is well established, whereas the prognostic influence of the reproductive pattern is less well described. A literature search with focus on three Danish studies is described. Status as parous/nulliparous and number of births appear to have no prognostic influence. Women who have their first child at an early age have a lower survival than women who have postponed their first childbirth. This may eventually be explained by selection, i.e. that women with an early first full-term pregnancy represent a group with a more malignant disease. Women diagnosed in the first two years after childbirth have a significantly lower survival, probably because the cancer, being subclinical during pregnancy, is affected by the high oestrogen concentrations with aggressive growth as the outcome. Pregnancy after treatment of breast cancer does not appear to have a negative influence on the prognosis.

[Should all younger patients with breast cancer be offered adjuvant cytotoxic chemotherapy?]

The aim of the study was to investigate whether young age at diagnosis is a negative prognostic factor in primary breast cancer and how stage of disease at diagnosis and treatment may influence such an association. It was conducted as a retrospective cohort study based on a population-based data-base of breast cancer diagnosis with detailed information on tumour characteristics, treatment regimens, and vital status and included 10,356 patients with primary breast cancer less than 50 years of age at diagnosis. The main outcome measures were relative risk of dying within the first ten years after diagnosis according to age at diagnosis, adjusted for effect of known prognostic factors and expected mortality. Overall, young patients with low risk disease who did not receive adjuvant treatment had a significantly increasing risk of dying with decreasing age at diagnosis (adjusted relative risk: 45-49 years: 1 (reference); 40-44 years: 1.12 (0.89-1.40); 35-39 years: 1.40 (1.10-1.78); < 35 years: 2.18 (1.64-2.89). However, a similar trend was not seen in young patients who received adjuvant cytotoxic therapy. We found the same difference as above when comparing women receiving no treatment with those receiving adjuvant cytotoxic therapy within strata of node negative patients and patients with the same tumour size. In conclusion, the negative prognostic effect of young age is almost exclusively seen in women diagnosed with low risk disease not receiving adjuvant cytotoxic therapy, whereas young women who receive adjuvant cytotoxic therapy have the same prognosis as middle-aged women. These results suggest that young women with breast cancer, on the basis of age alone, should be regarded as high risk patients and be given adjuvant cytotoxic therapy.

Factors influencing the effect of age on prognosis in breast cancer: population based study

OBJECTIVE

To investigate whether young age at diagnosis is a negative prognostic factor in primary breast cancer and how stage of disease at diagnosis and treatment influences such an association.

DESIGN

Retrospective cohort study based on a population based database of patients with breast cancer containing detailed information on tumour characteristics, treatment regimens, and survival.

SETTING

Denmark.

SUBJECTS

10 356 women with primary breast cancer who were less than 50 years old at diagnosis.

MAIN OUTCOME MEASURES

Relative risk of dying within the first 10 years after diagnosis according to age at diagnosis after adjustment for known prognostic factors and expected mortality.

RESULTS

Overall, young women with low risk disease who did not receive adjuvant treatment had a significantly increased risk of dying; risk increased with decreasing age at diagnosis (adjusted relative risk: 45-49 years (reference): 1; 40-44 years: 1.12 (95% confidence interval 0.89 to 1.40); 35-39 years: 1.40 (1.10 to 1.78); <35 years: 2.18 (1.64 to 2.89). However, no similar trend was seen in patients who received adjuvant cytotoxic treatment. The increased risk in younger women who did not receive adjuvant treatment compared with those who did remained when women were grouped according to presence of node negative disease and by tumour size.

CONCLUSION

The negative prognostic effect of young age is almost exclusively seen in women diagnosed with low risk disease who did not receive adjuvant cytotoxic treatment. These results suggest that young women with breast cancer, on the basis of age alone, should be regarded as high risk patients and be given adjuvant cytotoxic treatment.

Variations in prognostic factors in primary breast cancer throughout the menstrual cycle

AIMS

We investigated whether menstrual cycle dependent variations in prognostic factors are detectable in malignant breast tissue.

METHODS

Since 1977 the Danish Breast Cancer Cooperative Group has collected population-based information about primary clinical data, treatment regimens and follow-up status on Danish women with breast cancer. Information about last menstrual periods prior to surgery was obtained from files recorded at the time of admission for primary surgery. Included in this study were 1060 patients self-reported to be regularly menstruating and with a menstrual period within 6 weeks of surgery and who were operated in a single-step procedure. None of the patients were current users of exogenous hormones at the time of surgery. Variations of prognostic factors throughout the menstrual cycle were evaluated.

RESULTS

Overall, no significant correlation between endogenous hormone fluctuations and oestrogen receptor (ER) status and progesterone receptor (PgR) status were found. Furthermore, we observed no cycle-dependent variation for mitotic index, lymph node involvement or tumour size.

CONCLUSIONS

The classical prognostic factors in breast cancer did not differ significantly throughout the menstrual cycle in the present study.

Parity, age at first childbirth and the prognosis of primary breast cancer

Reproductive factors are known to be aetiologically important in breast cancer, but less is known regarding their effect on breast cancer prognosis. We have investigated the prognostic effect of age at first birth and total parity using data from the Danish Breast Cancer Cooperative Group that, since 1977, has collected population-based information on tumour characteristics, treatment regimes and follow-up status on Danish women with breast cancer. Details of pregnancy history were added from the Danish Civil Registration System and the National Birth Registry. Included in the study were 10,703 women with primary breast cancer. After adjusting for age and stage of disease (tumour size, axillary nodal status and histological grading), the number of full-term pregnancies was found without prognostic value. However, women with primary childbirth between 20 and 29 years experienced a significantly reduced risk of death compared with women with primary childbirth below the age of 20 years [20-24 years: relative risk (RR) = 0.88, 95% confidence interval (CI) 0.78-0.99; 25-29 years: RR = 0.80, 95% CI 0.70-0.91]. Further adjustment for oestrogen receptor status did not influence these results. The effect was not modified by age at diagnosis, tumour size or nodal status. In conclusion, low age at first childbirth, but not parity, was associated with a poor prognosis of breast cancer. We speculate whether women who develop breast cancer despite an early first full-term pregnancy might represent a selected group with a more malignant disease.

Time since childbirth and prognosis in primary breast cancer: population based study

OBJECTIVE

To investigate whether time since birth of last child was of prognostic importance in women with primary breast cancer.

DESIGN

Retrospective cohort study based on a population based database of breast cancer diagnoses with detailed information on tumour characteristics, treatment regimens, reproductive factors, and vital status.

SETTING

Denmark.

SUBJECTS

5652 women with primary breast cancer aged 45 years or less at the time of diagnosis.

MAIN OUTCOME MEASURES

5 and 10 year survival; relative risk of dying.

RESULTS

Women diagnosed in the first 2 years after last childbirth had a crude 5 year survival of 58.7% and 10 year survival of 46.1% compared with 78.4% and 66.0% for women whose last childbirth was more than 2 years before their diagnosis. After adjustment for age, reproductive factors, and stage of disease (tumour size, axillary nodal status, and histological grading), a diagnosis sooner than 2 years since last childbirth was significantly associated with a poor survival (relative risk 1.58, 95% confidence interval 1.24 to 2.02) compared with women who gave birth more than 5 years previously. Further analyses showed that the effect was not modified by age at diagnosis, tumour size, and nodal status.

CONCLUSIONS

A diagnosis of breast cancer less than 2 years after having given birth is associated with a particularly poor survival irrespective of the stage of disease at debut. Therefore, a recent pregnancy should be regarded as a negative prognostic factor and should be considered in counselling these patients and in the decisions regarding adjuvant treatment.