Multiparity and the risk of premenopausal breast cancer: different effects across ethnic groups in Singapore.

BACKGROUND: The relationship between multiparity and premenopausal breast cancer risk is different in Caucasian, African-American and Hispanic women. For Asian women, this relationship has never been well studied. METHODS: Within the Singapore Birth Registry, we selected all women who had a first child between 1986 and 2002 (169,936 Chinese, 40,521 Malay, 17,966 Indian). We linked them to the Singapore Cancer Registry data to identify those who developed breast cancer after childbirth (n = 527). We used multivariate Cox analysis to examine the relationship between parity, ethnicity and premenopausal breast cancer risk. RESULTS: Compared to Chinese, Malay women had increased and Indian women had decreased risks of premenopausal breast cancer (adjusted Hazard Ratios [HRadj] 1.25 [1.0-1.6] and 0.48 [0.3-0.8] respectively). Multiparity did not modify the risk of premenopausal breast cancer in Chinese and Indians. In Malays there was a significant risk reduction with increasing parity (P (trend )0.037). Malay women with one, two and >or=3 children had premenopausal breast cancer risks (HR(adj)) of 1.86 (1.2-3.0), 1.52 (1.1-2.2) and 0.87 (0.6-1.3) respectively compared to their Chinese counterparts. CONCLUSIONS: The impact of multiparity on premenopausal breast cancer risk differs across ethnic groups in Singapore. Increasing parity reduces the risk of premenopausal breast cancer in Malay, but not in Chinese and Indian women. Uniparous Malay women have twice the risk of premenopausal breast cancer compared to uniparous Chinese. This excess risk disappears after giving birth to >or=3 children. Indian women have lower premenopausal breast cancer risks than Chinese, regardless of their parity status.

Use of alternative therapy in postmenopausal breast cancer patients treated with tamoxifen after surgery.

The goal of this study was to determine the frequency of alternative therapy use in postmenopausal women with early stage breast cancer who were enrolled in a randomized clinical trial designed to determine the value of breast irradiation after treatment with breast-conserving surgery and tamoxifen. A questionnaire was given to 300 patients, ages 52 to 90 years, after completion of radiation therapy (if any). Of the 290 respondents, 78 (27%) had used some form of alternative therapy. Of these, 60.3% started after the diagnosis of breast cancer. Users of alternative therapies were significantly younger than nonusers (67.0 +/- 8.4 years versus 70.0 +/- 8.7 years, p = 0.009) and they used a median of one type of therapy per person (range 1-13). Users of alternative therapies were more likely to have experienced symptoms (stiffness, pain, numbness, or swelling) in the ipsilateral shoulder or arm after treatment of their breast cancers compared to nonusers (odds ratio [OR] = 2.0, p = 0.02). This relationship between alternative therapy use and symptoms was strongest in the group who started alternative therapies after breast cancer diagnosis (OR = 2.1, p = 0.05). On multivariate analysis, younger age and radiotherapy treatment were related to alternative therapy use. In conclusion, 27% of patients with early stage breast cancer used alternative therapy. Users were more likely to be younger and to experience shoulder or arm symptoms after breast-conserving surgery with radiation.

Deep vein thrombosis and malignancy: a surgical oncologist's perspective.

Oncology patients are at increased risk of developing deep vein thrombosis (DVT) and its potentially fatal sequel, pulmonary embolism. This is due to multiple factors, including the presence of the malignancy itself, comorbid factors and therapy-related interventions. Issues that are peculiar to venous thrombosis in the oncology setting are discussed, based on a MEDLINE search of the English literature. These include the need to screen for malignancy in idiopathic DVT, a high index of suspicion for venous thrombosis in the cancer patient, the use of vena cava filters, and the anti-neoplastic effects of heparin. Asian patients appear to have a lower incidence of DVT compared to Caucasians. A recommended regimen for prophylaxis of DVT must take into account the varying thrombosis risk associated with different malignancies. Cancer patients not undergoing abdominal, pelvic or orthopaedic surgery (e.g. mastectomy) should use elastic compression stockings and be mobilized early, whereas low-molecular-weight heparin should be given to those undergoing more major surgery. In advanced malignancy, treatment of DVT palliates symptoms. These patients may need long-term anticoagulation with warfarin.

Factors influencing arm and axillary symptoms after treatment for node negative breast carcinoma.

BACKGROUND: The purpose of the current study was to identify the factors that contribute to postoperative arm symptoms following breast conserving surgery in a well-defined cohort of node negative breast carcinoma patients. METHODS: A convenience sample of 370 women >/= 50 years of age with node negative breast carcinoma who were participants in a randomized controlled trial designed to assess the need for breast radiation in addition to tamoxifen were surveyed. Axillary dissection was optional for patients 65 years or older and who were clinically node negative. RESULTS: A total of 65.1% (241/370) of women had ipsilateral shoulder or arm symptoms. Multivariate analysis revealed that axillary dissection, breast radiation, and younger age (odds ratio = 11.2, 1.65, and 3.8 respectively) were significantly (P < 0.05) associated with increased ipsilateral shoulder or arm symptoms. Treatment with axillary dissection and breast radiation were significant factors (P < 0.02) associated with the self-reporting of arm swelling (odds ratio = 4.4 and 2.0, respectively). Patients 70 years old or greater reported significantly fewer arm symptoms (odds ratio = 0.26, P < 0.05) after axillary dissection. CONCLUSIONS: Arm symptoms were present in about 80% of patients who underwent breast conserving surgery, axillary dissection, and breast radiation in the current study. These symptoms were significantly associated with the use of axillary dissection, breast radiation, and younger age. Older patients experienced fewer arm symptoms after standard treatment for node negative breast carcinoma, and thus older age should not be a contraindication to axillary dissection.