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I A Olivotto

Publications and source records attributed to I A Olivotto.

At least 19 recordsLinked to original sources
PubMed2006

Late risk of relapse and mortality among postmenopausal women with estrogen responsive early breast cancer after 5 years of tamoxifen.

BACKGROUND: Letrozole after 5 years of adjuvant tamoxifen results in a significant reduction in risk of recurrence from estrogen receptor (ER) positive breast cancer. An individualized estimate of the risk of relapse and death after 5 years of tamoxifen could improve decisions regarding extended hormonal therapy. METHODS: The British Columbia Breast Cancer Outcomes database was used to identify women aged 45 years or older at the time of diagnosis with early-stage (I-IIIA) breast cancer who received tamoxifen and were disease free 5 years after diagnosis. Ten-year breast cancer event rates and mortality were calculated as well as annualized hazard rates of recurrence. RESULTS: A total of 1086 women were identified with a median age of 64 years and follow-up of 10.5 years. The relative risk (RR) of death was 3.1 (P=0.003) and for recurrence was 1.7 (P=0.037) for N1 (one to three positive nodes) versus N0 (zero nodes positive) disease. N2 (four to nine nodes positive) had a RR of 5.8 (P<0.001) for death and 3.0 (P=0.002) for recurrence. Low tumor grade and high ER level subgroups had a more favorable prognosis. Annual breast cancer risk between years 6 and 10 was, respectively, 2.2%, 3.5% and 7.6% for N0, N1 and N2 disease and 2.6% and 4.5% for T1 and T2 breast cancer. CONCLUSION: T and N stages predicted late relapse and death from breast cancer in a population-based cohort of postmenopausal women. Risk estimates reported herein may be used to optimize decision making regarding adjuvant therapy after 5 years of tamoxifen.

Aged↗
PubMed2005

A comparative analysis of radiotherapy use and patient outcome in males and females with breast cancer.

BACKGROUND: The aim was to determine whether gender was a significant prognostic factor for post-mastectomy relapse, after accounting for known prognostic factors and delivery of radiotherapy. PATIENTS AND METHODS: All patients diagnosed with invasive breast cancer between 1 January 1989 and 31 December 1998 who had undergone total mastectomy as primary therapy were identified from the British Columbia Cancer Agency's Breast Cancer Outcomes Unit database. Patients with pT4 or M1 disease were excluded. A comparison of patient, tumour and treatment factors was made between males and females. Outcomes were analysed in terms of locoregional-relapse free survival, breast cancer-specific survival and overall survival. RESULTS: Sixty males and 4181 females were identified. Multivariable analysis revealed increased tumour size, positive margin status, delivery of chemotherapy, positive nodal status and male gender to be significantly associated with the use of post-mastectomy radiotherapy. Multivariable analysis revealed tumour size, nodal status, tumour grade and presence of vascular space invasion to be significantly associated with locoregional recurrence. Gender was not a prognostic factor for locoregional recurrence, breast cancer-specific survival or overall survival on univariable or multivariable analysis. CONCLUSIONS: These data suggest that gender is not a prognostic factor in patients undergoing mastectomy for early stage breast cancer. Men having mastectomy for breast cancer should receive adjuvant radiotherapy following guidelines similar to those developed for females.

Aged↗
PubMed2005

Comparison of 1- and 2-year screening intervals for women undergoing screening mammography.

We compared the long-term impact of 1- and 2-year screening mammography intervals using prognostic, screening, and outcome information for women aged 50-74 years obtained from the Screening Mammography Program of British Columbia in two time periods, prior to 1997 (policy of annual mammography) and after 1997 (biennial mammography). Survival was estimated for both periods using a prognostic model and the expected rate of interval and screen-detected cancers. The likelihood of a screen-detected cancer with annual screening was 2.32 per thousand screens and with biennial screening was 3.32 per thousand screens. The prognostic profile of screen-detected cancers was better than that of interval cancers. Among both screen-detected and interval cancers, the prognostic profiles with annual and biennial screening were similar. The estimated breast cancer-specific survival rates for women undergoing annual and biennial screening mammography were 95.2 and 94.6% at 5 years, and 90.4 and 89.2% at 10 years, respectively. Annual compared to biennial mammography was associated with a 1.2% increase in the estimated 10-year breast cancer-specific survival for women aged 50-74 years, diagnosed with invasive breast cancer after screening programme attendance.

Aged↗
PubMed2005

Postmastectomy radiotherapy reduces locoregional recurrence in elderly women with high-risk breast cancer.

AIMS: Clinical trials of adjuvant radiotherapy after mastectomy have largely excluded women aged 70 years or over, even though they comprise 30% of the breast cancer population. This study examined outcomes in elderly women with high-risk breast cancer treated with or without postmastectomy radiotherapy (PMRT). MATERIALS AND METHODS: Data were analysed for 233 women aged 70 years or over with high-risk breast cancer (tumours > 5 cm or > or = 4 positive axillary nodes) treated with mastectomy and referred to the British Columbia Cancer Agency from 1989 to 1997. Tumour and treatment characteristics were compared between two cohorts: women treated with PMRT (n = 147) vs women treated without PMRT (n = 86). Univariate and multivariate analyses of 10-year Kaplan-Meier locoregional recurrence (LRR), distant recurrence, breast cancer-specific survival and overall survival were carried out. RESULTS: Median follow-up time was 5.5 years. The distribution of tumour sizes was similar in the two groups. Compared with women treated without PMRT, higher proportions of women who underwent PMRT had four or more positive nodes (83% vs 67%, P = 0.01) and positive surgical margins (14% vs 4%, P = 0.02). Systemic therapy, used in 94% of women, was comparable in the two cohorts (P = 0.63). Elderly women treated with PMRT had significantly lower LRR compared with women treated without PMRT (16% vs 28%, P = 0.03). No differences in distant recurrence, breast cancer-specific survival or overall survival were observed in the two treatment groups (all P > 0.05). On multivariate analysis, the omission of PMRT and the presence of high-grade histology were significant predictors of LRR, whereas an increasing number of positive nodes was significantly associated with distant recurrence and overall survival. CONCLUSIONS: In women aged 70 years or over with tumours greater than 5 cm or four or more positive nodes, significantly lower LRR was observed in women treated with radiotherapy compared with women treated without radiotherapy. PMRT should be considered in the management of elderly women with these high-risk characteristics.

Aged↗
PubMed2005

Short communication: Setup variations in locoregional radiotherapy for breast cancer: an electronic portal imaging study.

Recent trials demonstrating a survival benefit with locoregional radiotherapy (LRRT) to the chest wall and regional nodes in women with node-positive breast cancer have led to increased use of complex techniques to match three or more radiation fields, but information on setup reproducibility with LRRT for breast cancer is scarce. This study reports the magnitude and directions of random and systematic deviations in LRRT for breast cancer using an offline electronic portal imaging verification protocol. Electronic portal images (EPIs) of 46 consecutive women treated with LRRT for breast cancer from March 2001 to February 2002 with LRRT were analysed. Comparisons of EPIs to the corresponding digitally reconstructed radiographs were performed offline with anatomy matching. Displacements in mm were recorded in the superior-inferior (SI), medial-lateral (ML), and anterior-posterior (AP) directions. Random errors ranged from 2.0 mm to 2.5 mm for the breast/chest wall tangential treatments and 2.3 mm to 3.9 mm for the supraclavicular nodal treatments. Systematic errors occurred to a greater degree in the AP direction for the tangential fields and in the ML direction for the supraclavicular field. Displacements of > or =10 mm were found in 1.2% of breast/chest wall tangential treatments and in 6.2% of supraclavicular nodal treatments. These data demonstrate that EPI is a useful tool to verify setup reproducibility in LRRT for breast cancer.

Adult↗
PubMed2004

The difference between study recommendations, stated policy, and actual practice in a clinical trial.

BACKGROUND: We determined whether physicians involved in a clinical trial adhere to the study recommendations or the stated policy of their treatment centre with respect to the administration of boost radiation after breast conserving surgery. PATIENTS AND METHODS: Boost radiation treatment policy was determined by survey at 25 oncology centres involved in a randomised trial of breast or breast plus nodal radiation in Canada. Actual practice was compared with stated policy and study recommendations. RESULTS: Among 248 subjects, 201 (81%) were treated according to stated policy [kappa=0.40, 95% confidence intervals (CI) 0.27-0.52; P<0.0001], indicating only a fair to moderate agreement between stated and actual practice, while 232 (94%) were treated according to study recommendations (kappa=0.59, 95% CI 0.40-0.77; P<0.0001), indicating moderate to near substantial agreement between study recommendations and actual practice (P=0.88 for z-test of difference). In a multivariate analysis, subjects who had invasive disease at a resection margin were more likely to get a boost than those with margins clear of invasive tumour by 2 mm [odds ratio (OR) 49, 95% CI 7.6-322; P<0.0001]. CONCLUSIONS: Physicians appear compliant with study recommendations for a non-randomised manoeuvre in a clinical trial, possibly at the expense of compliance with stated local policy. Clinical trial protocols should incorporate standard practice.

Adult↗
PubMed2002

Prognostic significance of the number of axillary lymph nodes removed in patients with node-negative breast cancer.

PURPOSE: The objective of the study was to evaluate the association between the number of lymph nodes removed at axillary dissection and recurrence and survival for patients with node-negative invasive breast cancer. PATIENTS AND METHODS: Subjects were 2,278 women with pathologically node-negative invasive breast cancer, diagnosed from 1989 to 1993 in British Columbia, Canada. Women aged > or = 90 years, with pure in-situ, bilateral invasive breast cancer or T4, N1, N2, or M1 stage, or who had axillary radiation were excluded. Two groups were defined for analysis: node-negative with no systemic therapy (n = 1,468) and node-negative with systemic therapy (n = 810). Median follow-up was 7.5 years. Prognostic variables assessed were age at diagnosis, tumor size, tumor grade, invasion of lymphatics, veins, or nerves, estrogen receptor status, and number of nodes removed. RESULTS: For patients not receiving systemic therapy, regional relapse was significantly increased with smaller numbers of nodes removed (P =.03). There was a trend toward shorter overall survival with fewer nodes removed (P =.06). Node-negative patients who received systemic therapy did not have a higher regional relapse rate or shorter overall survival when fewer nodes were recovered. CONCLUSION: Recovery of a small number of negative lymph nodes at axillary dissection likely understages patients and leads to undertreatment, resulting in an increased regional relapse rate and poorer survival. The use of systemic therapy may overcome this effect. The number of nodes removed, in conjunction with other prognostic factors, may be useful in selecting node-negative patients for systemic therapy.

Adolescent↗
PubMed2002

Mega-dose vitamins and minerals in the treatment of non-metastatic breast cancer: an historical cohort study.

BACKGROUND: Alternative therapies such as mega-dose vitamins and minerals are commonly used by women with breast cancer, but their effect on recurrence and survival have rarely been evaluated. METHODS: Survival and recurrence outcomes for 90 women with unilateral non-metastatic breast cancer diagnosed between 1989 and 1998, and who had been prescribed mega-doses of beta-carotene, vitamin C, niacin, selenium, coenzyme Q10, and zinc in addition to standard therapies were compared with matched controls. The 90 treated patients were prescribed combinations from three to six of the vitamins and minerals listed above. The controls were matched (2:1) to the vitamin/mineral patients for age at diagnosis, presence of axillary lymph node metastasis, tumor stage, grade, estrogen receptor status, year of diagnosis, and prescription of systemic therapy. All subjects were patients of the British Columbia Cancer Agency, Vancouver Island Centre. FINDINGS: Median follow-up of surviving patients was 68 months (minimum 20 months, 133 months maximum). The vitamin/mineral patients and controls were well matched. Two endpoints were considered. Breast cancer-specific survival (p = 0.19) and disease-free survival (p = 0.08) times for the vitamin/mineral treated group were shorter, after adjusting for diagnostic variables using a Cox proportional hazards model. The hazard ratios for the vitamin/mineral treated group versus the control group were estimated at 1.75 (95% CI = 0.83-2.69) for disease-specific survival and 1.55 (95% CI = 0.94-2.54) for disease-free survival. Overall survival was similar for the two groups (log-rank test, p = 0.36). INTERPRETATION: Breast cancer-specific survival and disease-free survival times were not improved for the vitamin/mineral treated group over those for the controls.

Breast Neoplasms↗
PubMed2001

Waiting times from abnormal breast screen to diagnosis in 7 Canadian provinces.

BACKGROUND: Delay to breast cancer diagnosis following an abnormal screening result is associated with anxiety and personal disruption. We assessed the patterns and timeliness of diagnostic follow-up after breast cancer screening for women with abnormal results who attended organized screening programs in 7 provinces. METHODS: Using data from the Canadian Breast Cancer Screening Database, we identified 203,141 women aged 50-69 years who underwent screening in 1996 through provincially organized breast cancer screening programs in British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, Nova Scotia and Newfoundland. We prospectively followed women with an abnormal screening result through to the completion of the assessment process. We evaluated the waiting times from screening examination to first assessment, from screening examination to first imaging, from screening examination to diagnosis and from first assessment to diagnosis for 13,958 women, stratified according to screening program, mode of detection, whether a biopsy was performed and whether cancer was diagnosed. RESULTS: We observed considerable variations between and within programs in the time to diagnosis. The median time from screening examination to first assessment was 2.6 weeks. The median time from screening examination to diagnosis was 3.7 weeks; this time increased to 6.9 weeks for women undergoing biopsy. Even when no biopsy was performed, 10% of the women waited 9.6 weeks or longer for a diagnosis, as compared with 15.0 weeks or longer for 10% of the women undergoing biopsy. Among the women who had a biopsy, the use of core biopsy was associated with a shorter median time to diagnosis than was open biopsy, and those found to have cancer had shorter waiting times than women with benign biopsy findings. INTERPRETATION: Women undergoing assessment of an abnormal breast cancer screening result waited many weeks for a diagnosis, especially when a biopsy was performed. To ensure that targets for timeliness, adopted nationally in 1999, are realized, improved models of care or dissemination of existing efficient techniques to reach a diagnosis will be needed.

Aged↗
PubMed2001

Mammographically detected ductal carcinoma in situ of the breast treated with breast-conserving surgery and definitive breast irradiation: long-term outcome and prognostic significance of patient age and margin status.

PURPOSE: This study was performed to determine the long-term outcome for women with mammographically detected ductal carcinoma in situ (DCIS; intraductal carcinoma) of the breast treated with breast-conserving surgery followed by definitive breast irradiation. METHODS AND MATERIALS: An analysis was performed of 422 mammographically detected intraductal breast carcinomas in 418 women from 11 institutions in North America and Europe. All patients were treated with breast-conserving surgery followed by definitive breast irradiation. The median follow-up time was 9.4 years (mean, 9.4 years; range, 0.1-19.8 years). RESULTS: The 15-year overall survival rate was 92%, and the 15-year cause-specific survival rate was 98%. The 15-year rate of freedom from distant metastases was 94%. There were 48 local failures in the treated breast, and the 15-year rate of any local failure was 16%. The median time to local failure was 5.0 years (mean, 5.7 years; range, 1.0-15.2 years). Patient age at the time of treatment and final pathology margin status from the primary tumor excision were both significantly associated with local failure. The 10-year rate of local failure was 31% for patient age < or = 39 years, 13% for age 40-49 years, 8% for age 50-59 years, and 6% for age > or = 60 years (p = 0.0001). The 10-year rate of local failure was 24% when the margins of resection were positive, 9% when the margins of resection were negative, 7% when the margins of resection were close, and 12% when the margins of resection were unknown (p = 0.030). Patient age < or = 39 years and positive margins of resection were both independently associated with an increased risk of local failure (p = 0.0006 and p = 0.023, respectively) in the multivariable Cox regression model. CONCLUSIONS: The 15-year results from the present study demonstrated high rates of overall survival, cause-specific survival, and freedom from distant metastases following the treatment of mammographically detected ductal carcinoma in situ of the breast using breast-conserving surgery and definitive breast irradiation. Younger age and positive margins of resection were both independently associated with an increased risk of local failure. The 15-year results in the present study serve as an important benchmark for comparison with other treatment modalities. These results support the use of breast-conserving surgery and definitive breast irradiation for the treatment of appropriately selected patients with mammographically detected ductal carcinoma in situ of the breast.

Adult↗
PubMed2001

Salvage treatment for local recurrence after breast-conserving surgery and radiation as initial treatment for mammographically detected ductal carcinoma in situ of the breast.

BACKGROUND: The purpose of the current study is to evaluate the outcome of salvage treatment for local recurrence after breast-conserving surgery and radiation as initial treatment for mammographically detected ductal carcinoma in situ (DCIS; intraductal carcinoma) of the breast. METHODS: An analysis was performed of 42 patients with local only first failure (n = 41) or local-regional only first failure (n = 1) after breast-conserving surgery and radiation treatment had been given for DCIS of the breast. Surgical treatment at the time of local recurrence included mastectomy (n = 37; 88%) or excision (n = 5; 12%). Adjuvant systemic therapy at the time of local recurrence was chemotherapy (n = 3; 7%), tamoxifen (n = 8; 19%), both (n = 1; 2%), none (n = 29; 69%), or unknown (n = 1; 2%). The median interval from the time of initial treatment to local recurrence was 4.8 years (range = 1.0-15.2 yrs). The median follow-up after salvage treatment was 4.5 years (range = 0.2-12.8 yrs). RESULTS: At the time of the local recurrence, 22 patients (52%) had invasive ductal carcinoma, 18 patients (43%) had DCIS, 1 patient (2%) had invasive lobular carcinoma, and 1 patient (2%) had angiosarcoma. After salvage treatment, the rate of overall survival and the rate of cause specific survival for all 42 patients were 92% at both 5- and 8-years after treatment. The rate of freedom from distant metastases was 89% at 5 and 8 years. Favorable prognostic factors after salvage treatment were DCIS as the histology of the local recurrence and mammography only as the method of detection of the local recurrence. CONCLUSIONS: The results of salvage treatment in the current study demonstrated that local recurrences were salvaged with high rates of survival and freedom from distant metastases. These results support the use of breast-conserving surgery and radiation for initial management of DCIS of the breast.

Adult↗
PubMed2001

Clinical practice guidelines for the care and treatment of breast cancer: 11. Lymphedema.

OBJECTIVE: To provide information and recommendations for women and their physicians when making decisions about the management of lymphedema related to breast cancer. OPTIONS: Compression garments, pneumatic compression pumps, massage and physical therapies, other physical therapy modalities, pharmaceutical treatments. OUTCOMES: Symptom control, quality of life, cosmetic results. EVIDENCE: Systematic review of English-language literature retrieved primarily from MEDLINE (1966 to April 2000) and CANCERLIT (1985 to April 2000). Nonsystematic review of breast cancer literature published to October 2000. RECOMMENDATIONS: Pre- and postoperative measurements of both arms are useful in the assessment and diagnosis of lymphedema. Circumferential measurements should be taken at 4 points: the metacarpal-phalangeal joints, the wrists, 10 cm distal to the lateral epicondyles and 15 cm proximal to the lateral epicondyles. Clinicians should elicit symptoms of heaviness, tightness or swelling in the affected arm. A difference of more than 2.0 cm at any of the 4 measurement points may warrant treatment of the lymphedema, provided that tumour involvement of the axilla or brachial plexus, infection and axillary vein thrombosis have been ruled out. Practitioners may want to encourage long-term and consistent use of compression garments by women with lymphedema. One randomized trial has demonstrated a trend in favour of pneumatic compression pumps compared with no treatment. Further randomized trials are required to determine whether pneumatic compression provides additional benefit over compression garments alone. Complex physical therapy, also called complex decongestive physiotherapy, requires further evaluation in randomized trials. In one randomized trial no difference in outcomes was detected between compression garments plus manual lymph drainage versus compression garments alone. Clinical experience supports encouraging patients to consider some practical advice regarding skin care, exercise and body weight. [A patient version of these guidelines appears in Appendix 2.] VALIDATION: An initial draft of this document was developed by a task force sponsored by the BC Cancer Agency. It was updated and revised substantially by a writing committee and then submitted for further review, revision and approval by the Steering Committee for Clinical Practice Guidelines for the Care and Treatment of Breast Cancer. SPONSOR: The steering committee was convened by Health Canada. COMPLETION DATE: October 2000.

Bandages↗
PubMed2001

Health system costs of metastatic breast cancer.

To assess the costs of treating patients with incurable breast cancer, all health system costs during the interval from diagnosis of first recurrence or metastasis until death for 75 female subjects randomly selected from those known to have died of breast cancer in British Columbia, Canada between July 1, 1995 and December 31, 1996, were identified. Costs were determined from several databases within the British Columbia (BC) Ministry of Health, as well as from BC Cancer Agency patient charts. The mean total cost to the health system was CDN $36,474.33 (95% confidence interval $29,752-$43,196) per subject. The mean costs were highest for the youngest age group and lowest for the middle age group, but these only differed by $2,300. Inpatient costs accounted for the greatest proportion of the total, over 50% in all age groups. This data may be valuable in assessing the cost-effectiveness of interventions that are known to affect mortality due to breast cancer.

Adult↗
PubMed2000

A decision analysis of the effect of avoiding axillary lymph node dissection in low risk women with invasive breast carcinoma.

BACKGROUND: Evidence that avoiding axillary lymph node dissection (AxD) strikes an appropriate balance between morbidity and recurrence risk in patients with invasive breast carcinoma generally is anecdotal and without a formally quantified basis. The current study presents a decision analysis of the difference in 5-year disease free survival (DFS) rate between treatment scenarios with and without routine AxD. METHODS: To derive quantitative estimates of the effect of avoiding AxD on 5-year DFS, the authors examined outcomes for women undergoing 2 treatment scenarios: AxD or no AxD with adjuvant therapy decisions based on risk factors in the primary tumor. Eligible patients belonged to 2 lymph node metastases risk groups: low (patients without palpable lymph nodes and lymphatic or vascular invasion [LVI] negative tumors < or = 0.5 cm in greatest dimension) and moderate (patients with mammographically detected, LVI negative tumors, between 0.6-2.0 cm in greatest dimension or patients with palpable LVI negative tumors between 0.6-1.0 cm in greatest dimension with nonpalpable lymph nodes). Along with observed data regarding treatment and recurrence, the authors employed estimates of the efficacy of chemotherapy, tamoxifen, and regional radiation therapy derived from published randomized trials to estimate the 5-year DFS rate for treatment scenarios with and without AxD. RESULTS: Patients in the low risk group had a 5% risk of lymph node metastases. In these women, eliminating AxD and treating no patients with chemotherapy and/or tamoxifen resulted in a < 1% decrease in the 5-year DFS rate. Patients in the moderate risk group had a 10% risk of lymph node metastases. Eliminating AxD and treating only those women with Grade 3 tumors > 1 cm in greatest dimension with chemotherapy and/or tamoxifen resulted in a 1.8% decrease in the 5-year DFS rate. However, if all patients in this group were treated with chemotherapy and/or tamoxifen and no AxD, the 5-year DFS rate increased by 2.7%. CONCLUSIONS: In patients with a low risk of lymph node metastases, it was estimated that eliminating AxD may result in only minimal changes in the estimated 5-year DFS rate.

Adult↗
PubMed2000

Effect of time interval between breast-conserving surgery and radiation therapy on ipsilateral breast recurrence.

PURPOSE: To examine the effect of the time interval (interval) between breast-conserving surgery (BCS) and the start of radiation therapy (RT) on the subsequent risk of ipsilateral breast cancer recurrence (IBR). METHODS AND MATERIALS: We reviewed interval and a number of prognostic and treatment factors among 1,962 women treated with BCS and RT for invasive breast cancer diagnosed between January 1, 1989 and December 31, 1993 in British Columbia, Canada. Subjects were female, less than 90 years old at diagnosis, not treated with chemotherapy, not stage T4 or M1, and had survived more than 30 days from diagnosis. The cumulative incidence of IBR was estimated in four interval groups: 0-5, 6-8, 9-12, and 13+ weeks. Only 23 women had an interval of greater than 20 weeks between BCS and start of RT. To assess whether an imbalance of prognostic and treatment factors could be obscuring real differences between the interval groups, Cox proportional hazards regression analyses were conducted. RESULTS: Median follow-up was 71 months. The crude incidence of IBR for the entire sample was 3.9%. The cumulative incidence of IBR in the 6-8, 9-12, and 13+ week groups was not statistically significantly different from the cumulative incidence of IBR in the 0-5 week group. Multivariate analyses demonstrated that patients not using tamoxifen p = 0.027) and those with grade 3 histology (p = 0.003) were more likely to recur in the breast. Interval between BCS and RT was not a statistically significant predictor of breast recurrence when entered into a model incorporating tamoxifen use and tumor grade (0-5 vs. 6-8 weeks, p = 0.872; 0-5 vs. 9-12 weeks, p = 0.665; 0-5 vs. 13+ weeks, p = 0.573). CONCLUSIONS: We found no univariate or multivariate difference in ipsilateral breast cancer recurrence between intervals of 0 to 20 weeks from breast conserving surgery to start of radiation therapy, in a population-based, low risk group of women not receiving adjuvant chemotherapy, after controlling for other factors important in predicting ipsilateral breast cancer recurrence.

Adult↗