Biomaterial Database

Risk factors for contralateral breast cancer in Chennai (Madras), India. 1998

C K Gajalakshmi, and V Shanta, and M Hakama

Division of Epidemiology and Cancer Registry, Cancer Institute (WIA), Madras, India.

BACKGROUND This is the first cohort study conducted in India to identify risk factors for contralateral breast cancer (CBC) among patients with first primary breast cancer. METHODS Patients with first primary breast cancer diagnosed in 1960-1989 at the Cancer Institute (WIA) in Chennai, India, were followed-up until 31 December 1994. The risk of CBC was assessed among unilateral breast cancer (UBC) patients who survived for >12 months following the diagnosis of breast cancer and did not develop a second cancer (n = 2665) and among those who developed a CBC > or =12 months after the diagnosis of breast cancer (n = 39). RESULTS The age-adjusted incidence of CBC among women with UBC was seven times the incidence (per single breast) in the general population. Among women with UBC the relative risk (RR) was 4.5 (95% CI: 1.1-19.6) comparing those with and without a history of breast cancer in the mother, and 2.8 (95% CI: 1.2-6.7) comparing age at first birth 21-25 versus earlier. The RR was 0.3 (95% CI: 0.1-0.6) comparing those with and without hormone therapy for their UBC. Radiotherapy for the UBC had no significant effect on the incidence of CBC. CONCLUSIONS Positive family history of breast cancer and later age at first childbirth emerged as stronger risk factors for CBC than UBC. Hormone therapy reduces the risk of CBC.

UI	MeSH Term	Description	Entries
D007194	India	A country in southern Asia, bordering the Arabian Sea and the Bay of Bengal, between Burma and Pakistan. The capitol is New Delhi.	Republic of India
D008593	Menopause	The last menstrual period. Permanent cessation of menses (MENSTRUATION) is usually defined after 6 to 12 months of AMENORRHEA in a woman over 45 years of age. In the United States, menopause generally occurs in women between 48 and 55 years of age.	Change of Life, Female
D008598	Menstruation	The periodic shedding of the ENDOMETRIUM and associated menstrual bleeding in the MENSTRUAL CYCLE of humans and primates. Menstruation is due to the decline in circulating PROGESTERONE, and occurs at the late LUTEAL PHASE when LUTEOLYSIS of the CORPUS LUTEUM takes place.
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D001943	Breast Neoplasms	Tumors or cancer of the human BREAST.	Breast Cancer,Breast Tumors,Cancer of Breast,Breast Carcinoma,Cancer of the Breast,Human Mammary Carcinoma,Malignant Neoplasm of Breast,Malignant Tumor of Breast,Mammary Cancer,Mammary Carcinoma, Human,Mammary Neoplasm, Human,Mammary Neoplasms, Human,Neoplasms, Breast,Tumors, Breast,Breast Carcinomas,Breast Malignant Neoplasm,Breast Malignant Neoplasms,Breast Malignant Tumor,Breast Malignant Tumors,Breast Neoplasm,Breast Tumor,Cancer, Breast,Cancer, Mammary,Cancers, Mammary,Carcinoma, Breast,Carcinoma, Human Mammary,Carcinomas, Breast,Carcinomas, Human Mammary,Human Mammary Carcinomas,Human Mammary Neoplasm,Human Mammary Neoplasms,Mammary Cancers,Mammary Carcinomas, Human,Neoplasm, Breast,Neoplasm, Human Mammary,Neoplasms, Human Mammary,Tumor, Breast
D005260	Female		Females
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults
D012307	Risk Factors	An aspect of personal behavior or lifestyle, environmental exposure, inborn or inherited characteristic, which, based on epidemiological evidence, is known to be associated with a health-related condition considered important to prevent.	Health Correlates,Risk Factor Scores,Risk Scores,Social Risk Factors,Population at Risk,Populations at Risk,Correlates, Health,Factor, Risk,Factor, Social Risk,Factors, Social Risk,Risk Factor,Risk Factor Score,Risk Factor, Social,Risk Factors, Social,Risk Score,Score, Risk,Score, Risk Factor,Social Risk Factor
D015994	Incidence	The number of new cases of a given disease during a given period in a specified population. It also is used for the rate at which new events occur in a defined population. It is differentiated from PREVALENCE, which refers to all cases in the population at a given time.	Attack Rate,Cumulative Incidence,Incidence Proportion,Incidence Rate,Person-time Rate,Secondary Attack Rate,Attack Rate, Secondary,Attack Rates,Cumulative Incidences,Incidence Proportions,Incidence Rates,Incidence, Cumulative,Incidences,Person time Rate,Person-time Rates,Proportion, Incidence,Rate, Attack,Rate, Incidence,Rate, Person-time,Rate, Secondary Attack,Secondary Attack Rates