Primary MALT lymphoma of the breast: pathological and radiological characteristics

PURPOSE

Primary Mucosa-associated lymphoid tissue (MALT) lymphoma is a rare diagnosis in the breast, and clinical diagnosis based on radiological features is often challenging. This study aimed to evaluate the clinicopathological, and radiological characteristics of the patients diagnosed with primary breast MALT lymphoma.

METHODS

This study examined 18 cases of primary MALT lymphoma of the breast diagnosed at a single tertiary center between January 2002 to December 2020. Medical charts, radiological imaging and original pathology slides were reviewed for each case.

RESULTS

All cases were female (gender assigned at birth) and presented with a palpable mass or an incidental imaging finding. Imaging presentation ranged from mammographic asymmetries, circumscribed masses, and ultrasound masses lacking suspicious features. Seventeen cases were biopsied under ultrasound; one received a diagnostic excision biopsy. Microscopic examination of the breast specimens demonstrated atypical small lymphocyte infiltration with plasmacytoid differentiation and rare lymphoepithelial lesions. Immunohistochemistry was performed in all cases and established the diagnosis. Most patients were treated with radiotherapy, and only three were treated with chemotherapy. The median follow-up period was 4 years and 7.5 months, and all patients were alive at the last follow-up.

CONCLUSION

Primary MALT breast lymphomas are usually indolent and non-systemic, and local radiotherapy may effectively alleviate local symptoms. Radiological findings show overlap with benign morphological features, which can delay the diagnosis of this unusual etiology. Although further studies involving a larger cohort could help establish the clinical and radiological characteristics of primary breast MALT lymphomas, pathology remains the primary method of diagnosis.

TRIAL REGISTRATION NUMBER

University Health Network Ethics Committee (CAPCR/UHN REB number 19-5844), retrospectively registered.

Utilization of a rapid diagnostic centre during the COVID-19 pandemic reduced diagnostic delays in breast cancer

BACKGROUND

Access to breast imaging was restricted during the first wave of the COVID-19 pandemic. We assessed the impact of healthcare restrictions on the Gattuso Rapid Diagnostic Centre (GRDC) at the Princess Margaret Cancer Centre.

METHODS

A retrospective review of patients seen at the GRDC between March 12 - August 31, 2020 and the corresponding period from 2019 was performed.

RESULTS

There was an 18.6% decrease in patients seen at the GRDC (n = 429 in 2020 vs. 527 in 2019). Time from the first abnormal breast image to diagnosis was significantly shorter (17.4 days [IQR 13.0-21.8] in 2020 vs. 25.9 days [21.0-30.8] in 2019; p = 0.020) with no appreciable difference in time from diagnosis to consult or from consult to surgery.

CONCLUSION

The GRDC enabled patients with concerning breast symptoms to access breast imaging, which helped to ensure timely treatment during the first wave of the pandemic.

Abstract B020: Does surgical procedure influence psychosocial outcomes after treatment in women with ductal carcinoma in situ?

Objective: Rates of bilateral mastectomy are increasing in women with ductal carcinoma in situ (DCIS). We aim to characterize the trajectory of psychosocial outcomes after surgery in women with DCIS. Methods: We have been prospectively collecting psychosocial data on women receiving surgery for stage 0-III breast cancer at University Health Network in Toronto, Ontario, Canada since 2009. We queried our prospective database to identify all women receiving surgery for DCIS between May 2009 and January 2020. Women completed validated psychosocial questionnaires (e.g. BREAST-Q, Impact of Event Scale, Hospital Anxiety & Depression Scale) pre-operatively, and at 6 and 12 months following surgery. We analyzed the change in psychosocial scores between three surgical procedures (breast-conserving therapy, unilateral mastectomy and bilateral mastectomy) using linear mixed models, controlling for age and sociodemographic factors (e.g. ethnicity, education level, income and marital status). P values < .05 were significant. Results: 89 women with DCIS were identified, with a mean age of 52.4 ± 10.3 years. By surgical procedure, 7 women underwent breast-conserving therapy (8%), 46 underwent unilateral mastectomy (52%) and 36 underwent bilateral mastectomy (40%). Breast satisfaction (-8, P = .03) and sexual well-being (-10, P = .02) scores decreased over time but was not influenced by surgical procedure. Younger women had worse psychosocial well-being scores (-0.5/year, P = .02), with no impact of surgical procedure. There was a significant interaction between surgical procedure and time for chest physical well-being scores (P = .04); women having breast-conserving therapy had better chest physical well-being scores compared with both unilateral and bilateral mastectomy (with no difference between mastectomy groups). Unemployed women had worse chest physical well-being scores (-9, P = .04). There was a significant interaction between procedure and time for distress scores (P = .02); women having unilateral or bilateral mastectomy had higher distress scores before surgery but at 12 months, there was no difference between surgical procedures. Women with a higher annual income (≥80,000$) had higher breast satisfaction (+10, P = .03), psychosocial well-being (+14, P = .004), and sexual well-being (+12, P = .02), and lower distress (-12, P = .004 ) scores than women earning less than 80,000$ per year. There was a significant interaction (P = .01) between procedure and time for anxiety scores; while all surgical groups had mild anxiety scores at baseline, the anxiety scores for both unilateral and bilateral mastectomy groups improved to normal range over time while scores for women having breast-conserving therapy remained mild. Conclusions: Surgical procedure influences chest physical well-being, distress and anxiety scores in women with DCIS. Our data may help inform surgical decision-making for women with DCIS, and highlight a need for identifying women with high distress at diagnosis who may benefit from targeted psychosocial support.

Citation Format: David W. Lim, Helene Retrouvey, Isabel Kerrebijn, Benita Hosseini, Anne C. O'Neill, Tulin D. Cil, Toni Zhong, Stefan O.P. Hofer, David R. McCready, Kelly A. Metcalfe. Does surgical procedure influence psychosocial outcomes after treatment in women with ductal carcinoma in situ? [abstract]. In: Proceedings of the AACR Special Conference on Rethinking DCIS: An Opportunity for Prevention?; 2022 Sep 8-11; Philadelphia, PA. Philadelphia (PA): AACR; Can Prev Res 2022;15(12 Suppl_1): Abstract nr B020.

[SCREENING WOMEN AT HIGH RISK FOR BREAST CANCER - BRCA AND BEYOND]

BACKGROUND

Radiologic screening for breast cancer is performed with the goal of diagnosing the disease at an earlier stage, thus reducing morbidity and mortality. Screening recommendations for women at higher than average risk for breast cancer differ from those of women with an average risk, and include yearly breast MRI and mammography starting at a young age.

OBJECTIVES

Review the morbidity and mortality, and check whether the goal of early diagnosis was achieved in the participants of the High-Risk Ontario Breast Screening Program at the Princess Margaret Cancer Centre, Ontario Canada.

METHODS

A prospective cohort study was conducted of 2,081 women participating in the Princess Margaret Cancer Centre high risk screening program 2011-2018. Demographic, imaging, and if applicable biopsies, diagnosis and treatment data were captured in a prospectively maintained database starting with each participant's enrolment in the program.

RESULTS

A total of 32% of the participants were carriers of pathogenic variants in breast cancer related genes (BRCA, NF, CHEK2, TP53 etc.), 8% had a history of therapeutic chest radiotherapy, and the remaining 60% had a calculated elevated lifetime risk based on family history or personal risk factors, without an identifiable pathogenic mutation or previous radiation. During the follow-up period 89 breast cancer cases were diagnosed at the median age of 49 years. Median tumor size at diagnosis was 0.9 cm, correlating with a T1 disease. Nodal disease was found only in 4 cases. Breast cancer incidence was the same in the mutation carriers and chest radiotherapy groups, but 3-fold lower in the third group. Diagnosis of breast cancer was most commonly conducted by MRI imaging, and only 6% of cases were diagnosed based solely on mammography findings. Furthermore, 38 women died during follow-up, 29 of them (76%) were BRCA carriers who died from ovarian carcinoma.

CONCLUSIONS

Diagnosis at an early stage was achieved in this cohort of women followed in the high risk screening program. Most cases were diagnosed by MRI, thus emphasizing the importance of identifying women at high risk for breast cancer and referring them to the appropriate screening program.

Impact of patient, tumour and treatment factors on psychosocial outcomes in invasive breast cancer

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Background: In breast cancer, clinicians aim to improve survival while patients value quality of life. We aim to delineate the impact of patient, tumour and treatment factors on psychosocial outcomes after treatment. Methods: A prospective cohort of women with unilateral stage I-III breast cancer were recruited at University Health Network in Toronto, Canada between 2014-2017. Validated questionnaires (BREAST-Q, Impact of Event, Hospital Anxiety & Depression Scales) were completed pre-operatively, and 6 and 12 months after surgery. Change in psychosocial scores over time by surgical procedure was assessed using linear mixed models, controlling for age, pathologic stage, hormone (HR) and HER2 receptor, and treatments. Predictors of psychosocial outcomes at 12 months were assessed using multivariable linear regression models. P values <.05 were significant. Results: 413 women underwent unilateral lumpectomy (48%), unilateral mastectomy (36%) and bilateral mastectomy (16%). Pathologic stage were: 18 ypT0/Tis (4%), 201 stage I (49%), 136 stage II (33%) and 58 stage III (14%). Receptor profiles were as follows: 277 HR+/HER2- (68%), 59 HR+/HER2+ (14%), 31 HR-/HER2+ (8%) and 39 HR-/HER2- (10%). Over time, women having unilateral lumpectomy had the highest scores of breast satisfaction ( P<.01), psychosocial ( P<.01) and sexual ( P<.01) well-being, with no difference between unilateral versus bilateral mastectomy groups. Age was inversely related with distress ( P <.01), psychosocial ( P <.01) and physical ( P =.001) well-being. Radiotherapy was associated with worse breast satisfaction (-8.1, P<.01), psychosocial (-6.9, P<.01) and physical (-5.8, P<.01) well-being, while chemotherapy was associated with worse sexual well-being (-5.5, P=.04). Endocrine therapy was associated with worse distress (6.7, P <.01), physical (-5.2, P <.01) and sexual (-6.4, P =.03) well-being. Women with a pathologic complete response had less anxiety compared to stage I (-2.0, P=.03). Women with triple-negative disease had worse breast satisfaction (-8.0, P=.03), distress (8.0, P =.01), anxiety (2.4, P <.01) and psychosocial (-7.5, P =.047) well-being than HR+/HER2- disease. In our regression model at 12 months, surgical procedure was a significant predictor of breast satisfaction ( P <.01), psychosocial ( P<.01), physical ( P<.01) and sexual ( P<.01) well-being. HER2 positivity predicted worse satisfaction ( P=.045), psychosocial ( P =.047), physical ( P =.02) and sexual ( P =.01) well-being. Income level ( P=.01) predicted breast satisfaction and physical well-being. Ethnicity (P <.01) and education level (P =.04) predicted distress scores. Conclusions: Psychosocial functioning after breast cancer is influenced by an interplay between patient, tumour and treatment factors. Delineating these influences identifies potentially modifiable factors with de-escalation therapy and enhancing psychosocial support.

Longitudinal Study of Psychosocial Outcomes Following Surgery in Women with Unilateral Nonhereditary Breast Cancer

INTRODUCTION

Rates of bilateral mastectomy are rising in women with unilateral, nonhereditary breast cancer. We aim to characterize how psychosocial outcomes evolve after breast cancer surgery.

PATIENTS AND METHODS

We performed a prospective cohort study of women with unilateral, sporadic stage 0-III breast cancer at University Health Network in Toronto, Canada between 2014 and 2017. Women completed validated psychosocial questionnaires (BREAST-Q, Impact of Event Scale, Hospital Anxiety & Depression Scale) preoperatively, and at 6 and 12 months following surgery. Change in psychosocial scores was assessed between surgical groups using linear mixed models, controlling for age, stage, and adjuvant treatments. P < .05 were significant.

RESULTS

A total of 475 women underwent unilateral lumpectomy (42.5%), unilateral mastectomy (38.3%), and bilateral mastectomy (19.2%). There was a significant interaction (P < .0001) between procedure and time for breast satisfaction, psychosocial and physical well-being. Women having unilateral lumpectomy had higher breast satisfaction and psychosocial well-being scores at 6 and 12 months after surgery compared with either unilateral or bilateral mastectomy, with no difference between the latter two groups. Physical well-being declined in all groups over time; scores were not better in women having bilateral mastectomy. While sexual well-being scores remained stable in the unilateral lumpectomy group, scores declined similarly in both unilateral and bilateral mastectomy groups over time. Cancer-related distress, anxiety, and depression scores declined significantly after surgery, regardless of surgical procedure (P < .001).

CONCLUSIONS

Psychosocial outcomes are not improved with contralateral prophylactic mastectomy in women with unilateral breast cancer. Our data may inform women considering contralateral prophylactic mastectomy.

Abstract PS2-27: Benefits of a rapid diagnostic centre for breast cancer care during the COVID-19 pandemic

BACKGROUND: Changes in access to breast imaging and suspension of mammographic screening during the COVID-19 pandemic had the potential to significantly delay breast cancer diagnostic pathways. The Gattuso Rapid Diagnostic Centre (GRDC) is an innovative clinic that provides a patient-centered approach for investigation of suspicious breast abnormalities and sees approximately 1200 patients per year. The aim of this study was to assess the impact of the pandemic on patient volumes and imaging at this high-volume breast rapid diagnostic centre.

METHODS: A retrospective review of consecutive patients who presented to the GRDC from the start of the pandemic (March 12, 2020) until May 31, 2020 was performed. The number of patients, reason for referral, cancer detection rate (CDR), and waiting time from appointment to diagnosis were evaluated and compared to a corresponding time period in 2019.

RESULTS: A total of 168 new patients presented to the GRDC during the study period, corresponding to a 32.3% decrease in the number of patients compared to 2019 (n=248). Seventy-eight patients (46.4%) were referred due to the presence of a clinical palpable abnormality, which represented an increase of 13.8% (n=81 [32.7%] in 2019; p=0.005). Out of 168 patients, 69 were diagnosed with a breast malignancy, yielding a CDR of 41.1% during the pandemic versus 111 patients in 2019 (CDR of 44.8%; p= 0.456). The average time from appointment at GRDC to diagnosis was lower at 0.76 days vs 1.21 days in 2019. The rate of same day diagnosis was significantly higher at 39.5% vs 27.0% in 2019 (p=0.008). Twenty-five patients (14.9%) received neoadjuvant systemic therapy compared to 16 patients (6.5%) in 2019 (p=0.005). CONCLUSION: There were fewer patients presenting for breast investigations during the pandemic period and a significant increase in the percentage of patients with palpable masses as the cause for referral with no appreciable change in the CDR. The presence of a rapid diagnostic breast center enabled patients with concerning breast symptoms to access and receive expedited assessment. This ensured patients did not undergo diagnostic delays despite the health care restrictions that emerged during the COVID-19 pandemic.

Citation Format: Gary Ko, Sharmy Sarvanantham, Sangita Sequeira, Vrutika Prajapati, David R. McCready, Vivianne Freitas, Tulin D. Cil. Benefits of a rapid diagnostic centre for breast cancer care during the COVID-19 pandemic [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS2-27.

Robot-assisted nipple-sparing mastectomy: systematic review

BACKGROUND

The growing volume of studies of robot-assisted nipple-sparing mastectomy requires critical assessment. This review synthesizes the data on safety, feasibility, oncological and cosmetic outcomes, and patient-reported outcome measures (PROMs) for robot-assisted nipple-sparing mastectomy.

METHODS

A systematic review was performed using MEDLINE, MEDLINE In-Process/ePubs, Embase/Embase Classic, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, LILACS, PubMed, ClinicalTrials.Gov, WHO ICTRP and the grey literature. Original studies reporting on patients with breast cancer or at increased risk of breast cancer undergoing robot-assisted nipple-sparing mastectomy were included. Risk of bias was assessed using the Institute of Health Economics Case Series Quality Appraisal Checklist.

RESULTS

Of 7177 titles screened, eight articles were included, reporting on 249 robot-assisted nipple-sparing mastectomies in 187 women. The indication was either therapeutic (58·6 per cent) or prophylactic (41·4 per cent), with immediate reconstruction performed in 96·8 per cent. Surgical techniques followed a similar approach, with variations in incision, robot models, camera and insufflation. Postoperative morbidity included skin complications, lymphocele, infection, seroma, haematoma and skin ischaemia/necrosis. Complications specific to the nipple-areolar complex included ischaemia and necrosis. There were two conversions owing to haemorrhage, but no intraoperative deaths. Three patients had positive margins. Follow-up time ranged from 3·4 to 44·8 months. Locoregional recurrences were not observed. PROMs and objective cosmetic outcomes were reported inconsistently. Data on nipple sensitivity were not reported.

CONCLUSION

Robot-assisted nipple-sparing mastectomy is feasible with acceptable short-term outcomes but it remains in the assessment phase.

Psychosocial outcomes following surgery in women with unilateral, nonhereditary breast cancer

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Background: Rates of bilateral mastectomy continue to rise in average-risk women with unilateral breast cancer. We aim to characterize psychosocial predictors of surgical procedure and how psychosocial outcomes change over time after surgery for breast cancer. Methods: A prospective cohort of women with unilateral, nonhereditary breast cancer were recruited at University Health Network in Toronto, Canada between 2014-2017. Women completed validated psychosocial questionnaires (BREAST-Q) pre-operatively, and 6 and 12 months after surgery. Outcomes were assessed between three surgical groups (unilateral lumpectomy, unilateral mastectomy, bilateral mastectomy). Predictors of surgical procedure were identified using a multinomial logistic regression model. Change in psychosocial scores over time according to procedure was assessed using linear mixed models. All models control for age, stage, reconstruction and treatment. P values < .05 were considered statistically significant. Results: 506 women underwent surgery as follows: 216 unilateral lumpectomy (43%), 181 unilateral mastectomy (36%) and 109 bilateral mastectomy (22%). In the multinomial regression model, younger age (p < .01), and lower chest physical (p = .03) and sexual well-being (p = .02) predicted having bilateral mastectomy over unilateral lumpectomy while younger age (p < .01) and lower disease stage (p = .02) predicted bilateral mastectomy over unilateral mastectomy. The mixed model demonstrates that breast satisfaction follows a non-linear pattern of change over time, with 6- but not 12-month scores being significantly different from baseline (p = .015). Procedure predicts baseline satisfaction (p = .016), with bilateral mastectomy having worse satisfaction than unilateral lumpectomy. Procedure also predicts change in satisfaction, with unilateral and bilateral mastectomy having lower scores across time than lumpectomy. While a significant improvement in psychological well-being is detected by 12 months (p = .02), those with unilateral and bilateral mastectomy have worse psychological well-being over time compared to lumpectomy. Women having mastectomy start with worse physical well-being than those in the lumpectomy group, but their physical well-being does not decline as much as the lumpectomy group over time (p < .01). Conclusions: Definitive surgical procedure affects the trajectory of psychosocial functioning over time. This emerging data may be used to further facilitate surgical decision-making in women considering contralateral prophylactic mastectomy.

Patterns of Recurrence and Predictors of Survival in Breast Cancer Patients Treated with Neoadjuvant Chemotherapy, Surgery, and Radiation

PURPOSE

Neoadjuvant chemotherapy (NAC) is standard of care for locally advanced breast cancer. There is wide variation in radiation therapy (RT) practice and limited data describing locoregional relapse (LRR) after NAC. We hypothesized a low LRR risk with modern NAC, surgery, and RT and aimed to elucidate patterns of LRR and predictors of disease-free survival (DFS) and overall survival (OS) in these patients.

METHODS AND MATERIALS

Data from 416 patients with stage II/III breast cancer treated between 2008 and 2015 with NAC, surgery, and adjuvant RT were reviewed retrospectively. DFS and OS rates were calculated using the Kaplan-Meier method. The LRR rate was estimated using the cumulative incidence function, treating death as a competing risk. Multivariable survival analysis was performed using Cox regression.

RESULTS

Median follow-up was 4.7 years. Most patients had cT2/3 (74%) cN1 (61%) disease and underwent mastectomy (75%) and axillary dissection (84%). Pathologic complete response (pCR) was achieved in 22% of patients. There were 27 LRRs (including 4 isolated LRRs) and 89 distant failures. Two patients developed LRR 2 months after surgery, before adjuvant RT. LRR could be mapped in 23 patients: most (20) recurred within the RT field; 1 in- and out-of-field; and 2 out-of-field. Five-year LRR, DFS, and OS were 6.4%, 77%, and 90%, respectively. On multivariable analysis, triple-negative subtype (hazard ratio [HR] 2.82; 95% confidence interval [CI], 1.78-4.47; P < .001), stage III disease (HR 1.72; 95% CI, 1.11-2.69; P = .016), and non-pCR (HR 4.76; 95% CI 2.13-10.0; P < .001) were associated with poor DFS and OS (HR 4.13 [95% CI, 2.21-7.72; P < .001]; HR 1.94 [95% CI, 1.001-3.75; P = .049]; and HR 2.38 [95% CI, 0.98-5.88; P = .055], respectively).

CONCLUSIONS

Patients with breast cancer treated with modern NAC, surgery, and RT have a low 5-year LRR risk, with the majority occurring in-field. Triple-negative subtype, stage III disease, and non-pCR were associated with inferior DFS and OS.

Predictors of uptake of contralateral prophylactic mastectomy in women with nonhereditary breast cancer

BACKGROUND

The rates of contralateral prophylactic mastectomy (CPM) are increasing in women with breast cancer. Previous retrospective research has examined clinical and demographic predictors of the uptake of CPM. However, to the authors' knowledge, there has been very little prospective research to date that has examined psychosocial functioning prior to breast cancer surgery to determine whether psychosocial functioning predicts uptake of CPM. The current study was conducted to evaluate demographic, clinical, and psychosocial predictors of the uptake of CPM in women with unilateral breast cancer without a BRCA1 or BRCA2 mutation.

METHODS

Women with unilateral non-BRCA-associated breast cancer completed questionnaires prior to undergoing breast cancer surgery. Participants completed demographic and psychosocial questionnaires assessing anxiety, depression, cancer-related distress, optimism/pessimism, breast satisfaction, and quality of life. Pathological and surgical data were collected from medical charts.

RESULTS

A total of 506 women consented to participate, 112 of whom (22.1%) elected to undergo CPM. Age was found to be a significant predictor of CPM, with younger women found to be significantly more likely to undergo CPM compared with older women (P < .0001). The rate of CPM was significantly higher in women with noninvasive breast cancer compared with those with invasive breast cancer (P < .0001). Women who elected to undergo CPM had lower levels of presurgical breast satisfaction (P = .01) and optimism (P = .05) compared with women who did not undergo CPM.

CONCLUSIONS

Psychosocial functioning at the time of breast cancer surgery decision making impacts decisions related to CPM. Women who have lower levels of breast satisfaction (body image) and optimism are more likely to elect to undergo CPM. It is important for health care providers to take psychosocial functioning into consideration when discussing surgical options.

Is immediate breast reconstruction safe in women over 70? An analysis of the National Surgical Quality Improvement Program (NSQIP) database

PURPOSE

The safety of immediate breast reconstruction (IBR) in older women is largely unknown. This study aimed to determine the 30-day postoperative complication rates following IBR (implant-based or autologous) in older women (≥ 70 years) with breast cancer and to compare them to younger women (18-69 years).

METHODS

The National Surgical Quality Improvement Program (NSQIP) database was used to identify women with in situ or invasive breast cancer who underwent IBR (2005-2016). Outcomes included 30-day postoperative morbidity and mortality, which were compared across age groups stratified by type of reconstruction.

RESULTS

Of 28,850 women who underwent implant-based and 9123 who underwent autologous reconstruction, older women comprised 6.5% and 5.7% of the sample, respectively. Compared to younger women, older women had more comorbidities, shorter operative times, and longer length of hospital stay. In the implant-based reconstruction group, the 30-day morbidity rate was significantly higher in older women (7.5% vs 5.3%, p < 0.0001) due to higher rates of infectious, pulmonary, and venous thromboembolic events. Wound morbidity and prosthesis failure occurred equally among age groups. In the autologous reconstruction group, there was no statistically significant difference in the 30-day morbidity rates (older 9.5% vs younger 11.6%, p = 0.15). Both wound morbidity and flap failure rates were similar between the two age groups. For both reconstruction techniques, mortality within 30 days of breast surgery was rare.

CONCLUSION

Immediate breast reconstruction is safe in older women. These data support the notion that surgeons should discuss IBR as a safe and integral part of cancer treatment in well-selected older women.

Psychosocial Functioning in Women with Early Breast Cancer Treated with Breast Surgery With or Without Immediate Breast Reconstruction

PURPOSE

To compare psychosocial function outcomes in early breast cancer patients treated with breast-conserving surgery (BCS), mastectomy alone (MA), and mastectomy with immediate breast reconstruction (IBR) at 1 year after surgery.

METHODS

Early-stage (stage 0-2) breast cancer patients treated with BCS, MA, and IBR at the University Health Network, Toronto, Ontario, Canada between May 1 2015 and July 31 2016 were prospectively enrolled. Their changes in psychosocial functioning from baseline to 12 months following surgery were compared by using the BREAST-Q, Hospital Anxiety and Depression Scale, and Impact of Event Scale with ANOVA and linear regression.

RESULTS

There were 303 early-stage breast cancer patients: 155 underwent BCS, 78 MA, and 70 IBR. After multivariable regression accounting for age, baseline score, income, education, receipt of chemoradiation or hormonal therapy, ethnicity, cancer stage, and unilateral versus bilateral surgery, breast satisfaction was highest in BCS (72.1, SD 19.6), followed by IBR (60.0, SD 18.0), and MA (49.9, SD 78.0) at 12 months, p < 0.001. Immediate breast reconstruction had similar psychosocial well-being (69.9, SD 20.6) compared with BCS (78.5, SD 20.6), p = 0.07. Sexual and chest physical well-being were similar between IBR, BCS, and MA, p > 0.05.

CONCLUSIONS

Our study found that in a multidisciplinary breast cancer centre where all three breast ablative and reconstruction options are available to early breast cancer patients, either BCS or IBR can be used to provide patients with a higher degree of satisfaction and psychosocial well-being compared with MA in the long-term.

Abstract PD6-01: Prevalence and predictors of self-reported memory ability in a large sample of breast cancer survivors

Background: A substantial subset of women previously treated for breast cancer report deficits in cognitive abilities such as memory. Cancer-related cognitive dysfunction (CRCD) has been linked to a variety of factors including chemotherapy. However, the reported prevalence of symptoms is variable and investigations of CRCD correlates in large samples are limited. This study aimed to 1) investigate whether the prevalence of patient-reported memory problems differs as a function of having received chemotherapy and time-since-treatment; and 2) identify additional factors associated with patient-reported memory in a large sample of breast cancer survivors.

Method: In this cross-sectional cohort study, self-administered questionnaires including those assessing memory (Multifactorial Memory Questionnaire) and lifestyle behaviors were mailed to 1500 disease-free breast cancer survivors from three time-since-treatment cohorts (early: 6-18 months, middle: 2-4 years, or late: 5-12 years post-treatment). Demographic and clinical information was collected and confirmed from chart review. The prevalence of clinically significant memory dysfunction was estimated using published normative cut-off scores. We tested whether chemotherapy and time-since-treatment affected memory (analysis of variance), or increased the risk of significant memory dysfunction (odds ratio chi-squared test). Using a forward stepwise regression model, we explored whether patient characteristics (age, education, comorbidities, concussion history, adverse life events), type of treatment (chemotherapy, radiotherapy, hormonal therapy), or lifestyle behaviors (adherence to a Mediterranean diet, physical activity, sleep efficiency, stress management practices) were associated with patient-reported memory.

Results: 773 questionnaire packages were returned (mean age=60.4±11.7). 436 (56%) survivors had received chemotherapy (Ch+), and 337 (44%) had not (Ch-). 314 (41%) were early survivors, 244 (32%) were middle, and 215 (28%) were late. Ch+ reported poorer memory than Ch- (F(1, 764)=12.752, p&lt;0.001), with no effect of time-since-treatment or interaction. Prevalence of significant memory dysfunction was higher in Ch+ (28%) than in Ch- (15%) (OR=2.130, 95% CI 1.479-3.066). Younger age and history of concussion were significantly associated with worse patient-reported memory (p=0.002, p&lt;0.001). Unlike chemotherapy (p=0.018), neither radiation nor hormonal treatment was a significant predictor of memory symptoms. Increased physical activity (p=0.002) and higher sleep efficiency (p&lt;0.001) were associated with better memory. Survivors reporting greater memory symptoms also reported greater use of stress management techniques (p=0.026).

Conclusion: This large study indicates that chemotherapy doubles the risk of memory symptoms up to at least 10 years post-treatment. Results also point to sleep hygiene and physical activity as potentially meaningful targets for self-management training to reduce CRCD in breast cancer survivors.

Citation Format: Bernstein LJ, D'Amico DN, Richard NM, McCready DR, Howell D, Jones JM, Edelstein K. Prevalence and predictors of self-reported memory ability in a large sample of breast cancer survivors [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD6-01.

Abstract P5-16-01: Is breast reconstruction safe in women over 70? An analysis of the national surgical quality improvement program (NSQIP) database

Background:Less than 14% of older women undergo post-mastectomy breast reconstruction. A major reason for the low rate is the concern about post-operative complications. A thorough analysis of surgical complications by age group is limited in previous studies. The aim of this study is to determine the surgical complication rates of older women (≥70 years old) with breast cancer who underwent breast reconstruction and compare them to younger women (18–69 years old).

Methods: Data from the National Surgical Quality Improvement Program (NSQIP) database were used to identify women with carcinoma in situ and invasive breast cancer who underwent delayed or immediate breast reconstruction (2005-2016). The primary outcome was 30-day post-operative surgical complications; the secondary outcome was 30-day mortality.Patient demographics, comorbidities, and 30-day postoperative complications and mortality rates were compared across age groups and each type of reconstruction.

Results: Of 42,929 women who underwent breast reconstruction, 2,615 (6.1%) were older women. Although compared to young women, older women were more likely to have medical comorbidities their American Society of Anesthesiologists' (ASA) classification was lower.Tumor histology distribution was similar in both groups. Lymph node surgery and neoadjuvant chemotherapy was significantly less frequent among older women. Compared to young women, older women more frequently underwent immediate breast reconstruction (IBR) [n=2,405 (92%) versus n=33,580 (88.3%), p&lt;0.0001] but less frequently underwent delayed breast reconstruction [n=209 (8%) versus n=4,734 (11.7%), p&lt;0.0001]. Prosthesis-based reconstruction was the most common technique in both age groups. Autologous reconstruction was significantly less common amongst older women than young women [n=517 (19.8%) versus n=10,011 (24.8%), p&lt;0.0001]. Older women experienced higher rates of superficial surgical site infection (SSI) [n=69 (2.6%) versus n=716, (1.8%), p=0.002] and urinary tract infection [n=15 (0.6%) versus n=101 (0.3%) p =0.005]. However, the rates of deep SSI, dehiscence, pneumonia, thromboembolism, renal complications, cardiac events, and sepsis were similar between both groups. Older women had significantly lower rates of events of bleeding requiring transfusion [n=27 (1%) versus n=736 (1.8%), p=0.002] and flap failure [n=2 (0.4%) versus n=210 (2.1%), p=0.006). Return to the operating room within 30-days was similar between older and young women [n=171 (6.5%) versus n=2,821 (7.0%,) p=0.4]. Thirty-day deaths were rare events [older n=3 (0.1%) and young n=10 (0.02%), p=0.05].

Conclusions: Overall, 30-day postoperative complications in older women who undergo breast reconstruction are extremely low. Infection rates were slightly higher in the older group however; severe complications such as flap failure, bleeding, reoperation, and death were more common in young women. Age alone did not confer an increased risk of complications after breast reconstruction. Breast reconstruction can be safely offered to older women undergoing breast cancer treatment.

Citation Format: Angarita FA, McCready DR, Cil T. Is breast reconstruction safe in women over 70? An analysis of the national surgical quality improvement program (NSQIP) database [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-16-01.

Regulatory T Cells in Ovarian Cancer Are Characterized by a Highly Activated Phenotype Distinct from that in Melanoma

Purpose: Regulatory T (Treg) cells expressing the transcription factor FOXP3 are essential for the maintenance of immunologic self-tolerance but play a detrimental role in most cancers due to their ability to suppress antitumor immunity. The phenotype of human circulating Treg cells has been extensively studied, but less is known about tumor-infiltrating Treg cells. We studied the phenotype and function of tumor-infiltrating Treg cells in ovarian cancer and melanoma to identify potential Treg cell-associated molecules that can be targeted by tumor immunotherapies.Experimental Design: The phenotype of intratumoral and circulating Treg cells was analyzed by multicolor flow cytometry, mass cytometry, RNA-seq, and functional assays.Results: Treg cells isolated from ovarian tumors displayed a distinct cell surface phenotype with increased expression of a number of receptors associated with TCR engagement, including PD-1, 4-1BB, and ICOS. Higher PD-1 and 4-1BB expression was associated with increased responsiveness to further TCR stimulation and increased suppressive capacity, respectively. Transcriptomic and mass cytometry analyses revealed the presence of Treg cell subpopulations and further supported a highly activated state specifically in ovarian tumors. In comparison, Treg cells infiltrating melanomas displayed lower FOXP3, PD-1, 4-1BB, and ICOS expression and were less potent suppressors of CD8 T-cell proliferation.Conclusions: The highly activated phenotype of ovarian tumor-infiltrating Treg cells may be a key component of an immunosuppressive tumor microenvironment. Receptors that are expressed by tumor-infiltrating Treg cells could be exploited for the design of novel combination tumor immunotherapies. Clin Cancer Res; 24(22); 5685-96. ©2018 AACR.

Concurrent risk-reduction surgery in patients with increased lifetime risk for breast and ovarian cancer: an analysis of the National Surgical Quality Improvement Program (NSQIP) database

BACKGROUND

Patients with genetic susceptibility to breast and ovarian cancer are eligible for risk-reduction surgery. Surgical morbidity of risk-reduction mastectomy (RRM) with concurrent bilateral salpingo-oophorectomy (BSO) is unknown. Outcomes in these patients were compared to patients undergoing RRM without BSO using a large multi-institutional database.

METHODS

A retrospective cohort analysis was conducted using the American College of Surgeon's National Surgical Quality Improvement Program (NSQIP) 2007-2016 datasets, comparing postoperative morbidity between patients undergoing RRM with patients undergoing RRM with concurrent BSO. Patients with genetic susceptibility to breast/ovarian cancer undergoing risk-reduction surgery were identified. The primary outcome was 30-day postoperative major morbidity. Secondary outcomes included surgical site infections, reoperations, readmissions, length of stay, and venous thromboembolic events. A multivariate analysis was performed to determine predictors of postoperative morbidity and the adjusted effect of concurrent BSO on morbidity.

RESULTS

Of the 5470 patients undergoing RRM, 149 (2.7%) underwent concurrent BSO. The overall rate of major morbidity and postoperative infections was 4.5% and 4.6%, respectively. There was no significant difference in the rate of postoperative major morbidity (4.5% vs 4.7%, p = 0.91) or any of the secondary outcomes between patients undergoing RRM without BSO vs. those undergoing RRM with concurrent BSO. Multivariable analysis showed Body Mass Index (OR 1.05; p < 0.001) and smoking (OR 1.78; p = 0.003) to be the only predictors associated with major morbidity. Neither immediate breast reconstruction (OR 1.02; p = 0.93) nor concurrent BSO (OR 0.94; p = 0.89) were associated with increased postoperative major morbidity.

CONCLUSION

This study demonstrated that RRM with concurrent BSO was not associated with significant additional morbidity when compared to RRM without BSO. Therefore, this joint approach may be considered for select patients at risk for both breast and ovarian cancer.

Abstract P2-12-15: ReFilx- synthetic biodegradable soft tissue fillers for breast conserving surgery in breast cancer

Introduction: Breast conserving surgery (BCS) is the most common procedure performed in breast cancers, but it can often result in breast deformities that can have negative impacts on quality of life. With better treatments, more breast cancer survivors are expected to live longer, the demand for achieving optimal cosmetic outcomes has also increased accordingly. Currently, oncoplastic techniques involving local tissue rearrangement with or without contralateral balancing procedures are used in specialized centers to achieve breast symmetry in some patients. When a breast deformity occurs, corrective options include: fat grafting, autologous flap procedures and completion mastectomy with immediate reconstruction. These techniques have long operative times, longer length of hospital stay and higher complication rates. Commercially-available synthetic implants are fabricated in pre-determined sizes and thus are not suitable to reconstruct partial breast deformities of varying size and shape. We explored the use of amino-acid based biodegradable polyurethanes as tissue fillers for BCS due to their chemical versatility, superior mechanical properties and tailored biocompatibility. Objective: To evaluate novel biodegradable polymer constructs, referred to as ReFilx, as soft tissue fillers for BCS defects. Hypothesis: Implantation of ReFilx during BCS will maintain breast shape and size and promote tissue regeneration in and around the biodegradable biomaterial, in contrast to sham controls. Methods: Two ReFilx formulations with high porosity, mechanical properties (compressive modulus=45±6 kPa and 31±9 kPa) comparable to native breast tissue and a moderate degree of swelling (202±6% and 248±6%) were selected for implantation in porcine BCS defects. Three female Yucatan Minipigs (age=4 years, weight=100-120 kg, 12 breasts per pig) received BCS to remove normal breast tissue of approximately 2 cm diameter, after which the defects were filled with ReFilx Formulation A, ReFilx Formulation B, or no filler (sham control). At 6, 12, 24, and 36 weeks post-implantation (n=3 per group), ultrasound breast examinations and mastectomies of each selected group of breasts were performed. Samples were fixed in 10% buffered formalin and stained with H&E, Masson's Trichrome and immunohistomchemistry using CD31. Results: ReFilx formulations maintained breast size and shape, with similar stiffness to native breast tissue, while sham controls collapsed over 36 weeks. The ReFilx fillers supported cell and tissue infiltration and neovascularization, as indicated by Masson's Trichrome and CD31 staining, respectively, without eliciting foreign body giant cell formation, fibrosis, or chronic inflammation, commonly associated with implanted medical devices. Conclusions: ReFilx are promising soft tissue fillers for breast volume restoration, representing a simple, versatile, permanent, and aesthetically superior solution to prevent soft tissue deformities. Acknowledgements: MaRS PoP fund, grant # MI 2011-170, NSERC # SYN 430828. Haynes Connell Foundation Breast Cancer Fund.

Citation Format: Leong WL, Sharifpoor S, Battiston K, Charleton D, Corrigan M, McCready DR, Done SJ, Santerre JP. ReFilx- synthetic biodegradable soft tissue fillers for breast conserving surgery in breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-12-15.

Cost analysis of breast cancer diagnostic assessment programs

OBJECTIVES

Diagnostic assessment programs (daps) appear to improve the diagnosis of cancer, but evidence of their cost-effectiveness is lacking. Given that no earlier study used secondary financial data to estimate the cost of diagnostic tests in the province of Ontario, we explored how to use secondary financial data to retrieve the cost of key diagnostic test services in daps, and we tested the reliability of that cost-retrieving method with hospital-reported costs in preparation for future cost-effectiveness studies.

METHODS

We powered our sample at an alpha of 0.05, a power of 80%, and a margin of error of ±5%, and randomly selected a sample of eligible patients referred to a dap for suspected breast cancer during 1 January-31 December 2012. Confirmatory diagnostic tests received by each patient were identified in medical records. Canadian Classification of Health Intervention procedure codes were used to search the secondary financial data Web portal at the Ontario Case Costing Initiative for an estimate of the direct, indirect, and total costs of each test. The hospital-reported cost of each test received was obtained from the host-hospital's finance department. Descriptive statistics were used to calculate the cost of individual or group confirmatory diagnostic tests, and the Wilcoxon signed-rank test or the paired t-test was used to compare the Ontario Case Costing Initiative and hospital-reported costs.

RESULTS

For the 191 identified patients with suspected breast cancer, the estimated total cost of $72,195.50 was not significantly different from the hospital-reported total cost of $72,035.52 (p = 0.24). Costs differed significantly when multiple tests to confirm the diagnosis were completed during one patient visit and when confirmatory tests reported in hospital data and in medical records were discrepant. The additional estimated cost for non-salaried physicians delivering diagnostic services was $28,387.50.

CONCLUSIONS

It was feasible to use secondary financial data to retrieve the cost of key diagnostic tests in a breast cancer dap and to compare the reliability of the costs obtained by that estimation method with hospital-reported costs. We identified the strengths and challenges of each approach. Lessons learned from this study have to be taken into consideration in future cost-effectiveness studies.

The effect of surgery type on survival and recurrence in very young women with breast cancer

BACKGROUND

The impact of surgical treatment on outcomes in breast cacner in very young women remains unclear. We sought to determine the effect of surgery type on risk of recurrence and survival in a population-based cohort.

METHODS

All women diagnosed with breast cancer aged ≤35 (1994-2003) were identified from the Ontario Cancer Registry. Patient, tumor, and treatment variables, including primary surgery, recurrences, and death were abstracted from chart review. Cox regression models were fit to determine the effect of surgery type on recurrence and overall survival.

RESULTS

We identified 1,381 patients with 11-year median follow-up of which 793 (57%) had BCS. Of the remaining mastectomy patients, 52% had postmastectomy radiation. Overall, 41% of patients sustained a recurrence of any type and 31% died. Controlling for known confounders, there was no association between type of surgery and death from any cause (HR = 0.98, 95% CI = 0.78, 1.25) or first recurrence (HR = 0.93, 95% CI = 0.75, 1.14). Distant recurrence was most common (13% in BCS; 25.3% in mastectomy) with local recurrence 12.4% after BCS and 7.5% after mastectomy.

CONCLUSIONS

In this cohort of very young women who were selected for treatment with BCS and mastectomy, we found similar oncologic outcomes. J. Surg. Oncol. 2017;115:122-130. © 2017 Wiley Periodicals, Inc.

Society of Surgical Oncology Breast Disease Working Group Statement on Prophylactic (Risk-Reducing) Mastectomy

Over the past several years, there has been an increasing rate of bilateral prophylactic mastectomy (BPM) and contralateral prophylactic mastectomy (CPM) surgeries. Since publication of the 2007 SSO position statement on the use of risk-reducing mastectomy, there have been significant advances in the understanding of breast cancer biology and treatment. The purpose of this manuscript is to review the current literature as a resource to facilitate a shared and informed decision-making process regarding the use of risk-reducing mastectomy.

TARGIT-R (Retrospective): North American Experience with Intraoperative Radiation Using Low-Kilovoltage X-Rays for Breast Cancer

BACKGROUND

Single-dose intraoperative radiotherapy (IORT) is an emerging treatment for women with early stage breast cancer. The objective of this study was to define the frequency of IORT use, patient selection, and outcomes of patients treated in North America.

METHODS

A multi-institutional retrospective registry was created, and 19 institutions using low-kilovoltage IORT for the treatment of breast cancer entered data on patients treated at their institution before July 31, 2013. Patient selection, IORT treatment details, complications, and recurrences were analyzed.

RESULTS

From 2007 to July 31, 2013, a total of 935 women were identified and treated with lumpectomy and IORT. A total of 822 patients had at least 6 months' follow-up documented and were included in the analysis. The number of IORT cases performed increased significantly over time (p < 0.001). The median patient age was 66.8 years. Most patients had disease that was <2 cm in size (90 %) and was estrogen positive (91 %); most patients had invasive ductal cancer (68 %). Of those who had a sentinel lymph node procedure performed, 89 % had negative sentinel lymph nodes. The types of IORT performed were primary IORT in 79 %, secondary IORT in 7 %, or planned boost in 14 %. Complications were low. At a median follow-up of 23.3 months, crude in-breast recurrence was 2.3 % for all patients treated.

CONCLUSIONS

IORT use for the treatment of breast cancer is significantly increasing in North America, and physicians are selecting low-risk patients for this treatment option. Low complication and local recurrence rates support IORT as a treatment option for selected women with early stage breast cancer.

Abstract P4-03-05: Wide-field optical coherence tomography (WF-OCT) for near real-time, point-of-care assessment of margin status in breast-conserving surgery specimens: Results of a feasibility study at a high-volume single-centre

Wide-Field Optical Coherence Tomography (WF-OCT) is a non-destructive, non-contact light imaging modality capable of label-free visualization of the internal microscopic architecture of breast tissue specimens. Its unique combination of high-resolution imaging in near real-time with tissue penetration depths approaching 2-mm makes it a promising imaging modality for obtaining detailed surgical margin status in breast-conserving surgery (BCS) specimens. A prototype WF-OCT imaging platform developed by Perimeter Medical Imaging, Inc. (Toronto, Canada) has permitted fully-automated, dynamically-focused visualization of margin widths around the intact surfaces of freshly excised BCS specimens. Herein are reported the results of a feasibility study at a high-volume single-centre evaluating the routine use of WF-OCT for sampling of surgical margin status in BCS specimens at the point-of-care.

Methods: Women with biopsy confirmed breast cancer and scheduled for primary BCS were recruited at Princess Margaret Cancer Centre (Toronto, Canada). Standard medical care was not altered. Freshly excised BCS specimens including all lumpectomy samples were imaged by WF-OCT immediately prior to standard histological processing. The system acquired dynamically-focused, hemispherical coverage over two contra-lateral surfaces of the intact BCS specimen within the time constraints of the cold ischemic time window. High-resolution (10 μm) images of the tissue surface down to a 1 to 2-mm depth were obtained. Blinded assessments were performed on image data sets by two clinical readers (surgeon and radiologist) trained on a validated and unrelated data set correlating OCT images with histology slides. The readers were first asked to independently assess margin status using only blinded pre- and intra-operative knowledge (without OCT). Upon completion, the readers were provided OCT images of all scanned surface and similarly asked to assess the margin status with the additional OCT information. These assessments were subsequently evaluated by a breast pathologist comparing the OCT images and corresponding histopathology sections. The added utility of WF-OCT imaging information for margin prediction was studied.

Results: [Pending study completion in August 2015]. Through accurate correlation with the histopathologic gold standard, OCT demonstrated capability to differentiate tissue microstructures, including: distinctive patterns for adipose tissue, fibrous stroma, breast lobules and ducts, cysts and microcysts, as well as in-situ and invasive carcinomas.

Implications: The fully-automated WF-OCT imaging platform can integrate conveniently into standard pathological processing workflows to provide comprehensive sampling of surgical margin status in BCS specimens at the point-of-care. Clinical readers from surgical and radiological backgrounds can be trained to competently interpret WF-OCT images of BCS specimens for accurate prediction margin status. The implementation of WF-OCT at the point-of-care for routine surgical margin assessments will be further explored in future clinical trials.

Citation Format: Valic MS, Leong WL, Done SJ, Wilson BC, Kulkarni S, McCready DR, Niu CJ, Atachia Y, Munro EA, Rempel D. Wide-field optical coherence tomography (WF-OCT) for near real-time, point-of-care assessment of margin status in breast-conserving surgery specimens: Results of a feasibility study at a high-volume single-centre. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-03-05.

Regional Nodal Irradiation in Early-Stage Breast Cancer

BACKGROUND

Most women with breast cancer who undergo breast-conserving surgery receive whole-breast irradiation. We examined whether the addition of regional nodal irradiation to whole-breast irradiation improved outcomes.

METHODS

We randomly assigned women with node-positive or high-risk node-negative breast cancer who were treated with breast-conserving surgery and adjuvant systemic therapy to undergo either whole-breast irradiation plus regional nodal irradiation (including internal mammary, supraclavicular, and axillary lymph nodes) (nodal-irradiation group) or whole-breast irradiation alone (control group). The primary outcome was overall survival. Secondary outcomes were disease-free survival, isolated locoregional disease-free survival, and distant disease-free survival.

RESULTS

Between March 2000 and February 2007, a total of 1832 women were assigned to the nodal-irradiation group or the control group (916 women in each group). The median follow-up was 9.5 years. At the 10-year follow-up, there was no significant between-group difference in survival, with a rate of 82.8% in the nodal-irradiation group and 81.8% in the control group (hazard ratio, 0.91; 95% confidence interval [CI], 0.72 to 1.13; P=0.38). The rates of disease-free survival were 82.0% in the nodal-irradiation group and 77.0% in the control group (hazard ratio, 0.76; 95% CI, 0.61 to 0.94; P=0.01). Patients in the nodal-irradiation group had higher rates of grade 2 or greater acute pneumonitis (1.2% vs. 0.2%, P=0.01) and lymphedema (8.4% vs. 4.5%, P=0.001).

CONCLUSIONS

Among women with node-positive or high-risk node-negative breast cancer, the addition of regional nodal irradiation to whole-breast irradiation did not improve overall survival but reduced the rate of breast-cancer recurrence. (Funded by the Canadian Cancer Society Research Institute and others; MA.20 ClinicalTrials.gov number, NCT00005957.).

Identification of a Low-Risk Luminal A Breast Cancer Cohort That May Not Benefit From Breast Radiotherapy

PURPOSE

To determine the prognostic and predictive value of intrinsic subtyping by using immunohistochemical (IHC) biomarkers for ipsilateral breast relapse (IBR) in participants in an early breast cancer randomized trial of tamoxifen with or without breast radiotherapy (RT).

PATIENTS AND METHODS

IHC analysis of estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2 (HER2), cytokeratin 5/6, epidermal growth factor receptor, and Ki-67 was conducted on 501 of 769 available blocks. Patients were classified as luminal A (n = 265), luminal B (n = 165), or high-risk subtype (luminal HER2, n = 22; HER2 enriched, n = 13; basal like, n = 30; or triple-negative nonbasal, n = 6). Median follow-up was 10 years.

RESULTS

Classification by subtype was prognostic for IBR (10-year estimates: luminal A, 5.2%; luminal B, 10.5%; high-risk subtypes, 21.3%; P < .001). Luminal subtypes seemed to derive less benefit from RT (luminal A hazard ratio [HR], 0.40; luminal B HR, 0.51) than high-risk subtypes (HR, 0.13); however, the overall subtype-treatment interaction term was not significant (P = .26). In an exploratory analysis of women with clinical low-risk (age older than 60 years, T1, grade 1 or 2) luminal A tumors (n = 151), 10-year IBR was 3.1% versus 11.8% for the high-risk cohort (n = 341; P = .0063). Clinical low-risk luminal A patients had a 10-year IBR of 1.3% with tamoxifen versus 5.0% with tamoxifen plus RT (P = .42). Multivariable analysis showed that RT (HR, 0.31; P < .001), clinical risk group (HR, 2.2; P = .025), and luminal A subtype (HR, 0.25; P < .001) were significantly associated with IBR.

CONCLUSION

IHC subtyping was prognostic for IBR but was not predictive of benefit from RT. Further studies may validate the exploratory finding of a low-risk luminal A group who may be spared breast RT.

Cancer-related fatigue and associated disability in post-treatment cancer survivors

PURPOSE

Cancer-related fatigue (CRF) is the most prevalent and distressing symptom among cancer patients and survivors. However, research on its prevalence and related disability in the post-treatment survivorship period remains limited. We sought to describe the occurrence of CRF within three time points in the post-treatment survivorship trajectory.

METHODS

A self-administered mail-based questionnaire which included the Functional Assessment of Cancer Therapy-Fatigue (FACT-F) and the World Health Organisation Disability Assessment Schedule 2.0 was sent to three cohorts of disease-free breast, prostate or colorectal cancer survivors (6-18 months; 2-3 years; and 5-6 years post-treatment). Clinical information was extracted from chart review. Frequencies of significant fatigue by diagnostic group and time cohorts were studied and compared. Multivariate logistic regressions were conducted to examine the associations between CRF and demographic, clinical, and psychosocial variables.

RESULTS

One thousand two hundred ninety-four questionnaire packages were returned (63 % response rate). A total of 29 % (95 % CI [27 % to 32 %]) of the sample reported significant fatigue (FACT-F ≤34), and this was associated with much higher levels of disability (p < 0.0001). Breast (40 % [35 % to 44 %]) and colorectal (33 % [27 % to 38 %]) cancer survivors had significantly higher rates of fatigue compared with the prostate group (17 % [14 % to 21 %]) (p < 0.0001). Fatigue levels did not differ between the three time cohorts. The main factors associated with CRF included physical symptom burden, depression, and co-morbidity (AUC, 0.919 [0.903 to 0.936]).

CONCLUSIONS

Clinically relevant levels of CRF are present in approximately 1/3 of cancer survivors up to 6 years post-treatment, and this is associated with high levels of disability.

IMPLICATIONS FOR CANCER SURVIVORS

Clinicians need to be aware of the chronicity of CRF and assess for it routinely in medical practice. While there is no gold standard treatment, non-pharmacological interventions with established efficacy can reduce its severity and possibly minimize its disabling impact on patient functioning. Attention must be paid to the co-occurrence and need for possible treatment of depression and other co-occurring physical symptoms as contributing factors.

Changes in insulin receptor signaling underlie neoadjuvant metformin administration in breast cancer: a prospective window of opportunity neoadjuvant study

INTRODUCTION

The antidiabetic drug metformin exhibits potential anticancer properties that are believed to involve both direct (insulin-independent) and indirect (insulin-dependent) actions. Direct effects are linked to activation of AMP-activated protein kinase (AMPK) and an inhibition of mammalian target of rapamycin mTOR signaling, and indirect effects are mediated by reductions in circulating insulin, leading to reduced insulin receptor (IR)-mediated signaling. However, the in vivo impact of metformin on cancer cell signaling and the factors governing sensitivity in patients remain unknown.

METHODS

We conducted a neoadjuvant, single-arm, "window of opportunity" trial to examine the clinical and biological effects of metformin on patients with breast cancer. Women with untreated breast cancer who did not have diabetes were given 500 mg of metformin three times daily for ≥2 weeks after diagnostic biopsy until surgery. Fasting blood and tumor samples were collected at diagnosis and surgery. Blood glucose and insulin were assayed to assess the physiologic effects of metformin, and immunohistochemical analysis of tumors was used to characterize cellular markers before and after treatment.

RESULTS

Levels of IR expression decreased significantly in tumors (P = 0.04), as did the phosphorylation status of protein kinase B (PKB)/Akt (S473), extracellular signal-regulated kinase 1/2 (ERK1/2, T202/Y204), AMPK (T172) and acetyl coenzyme A carboxylase (S79) (P = 0.0001, P < 0.0001, P < 0.005 and P = 0.02, respectively). All tumors expressed organic cation transporter 1, with 90% (35 of 39) exhibiting an Allred score of 5 or higher.

CONCLUSIONS

Reduced PKB/Akt and ERK1/2 phosphorylation, coupled with decreased insulin and IR levels, suggest insulin-dependent effects are important in the clinical setting. These results are consistent with beneficial anticancer effects of metformin and highlight key factors involved in sensitivity, which could be used to identify patients with breast cancer who may be responsive to metformin-based therapies.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00897884. Registered 8 May 2009.

B7-H4 expression by nonhematopoietic cells in the tumor microenvironment promotes antitumor immunity

The B7 family plays a critical role in both positive and negative regulation of immune responses by engaging a variety of receptors on lymphocytes. Importantly, blocking coinhibitory molecules using antibodies specific for CTLA-4 and PD-1 enhances tumor immunity in a subset of patients. Therefore, it is critical to understand the role of different B7 family members since they may be suitable therapeutic targets. B7-H4 is another member that inhibits T-cell function, and it is also upregulated on a variety of tumors and has been proposed to promote tumor growth. Here, we investigate the role of B7-H4 in tumor development and show that B7-H4 expression inhibits tumor growth in two mouse models. Furthermore, we show that B7-H4 expression is required for antitumor immune responses in a mouse model of mammary tumorigenesis. We found that the expression levels of B7-H4 correlate with MHC class I expression in both mouse and human samples. We show that IFNγ upregulates B7-H4 expression on mouse embryo fibroblasts and that the upregulation of B7-H4 on tumors is dependent on T cells. Notably, patients with breast cancer with increased B7-H4 expression show a prolonged time to recurrence. These studies demonstrate a positive role for B7-H4 in promoting antitumor immunity.

Sentinel node biopsy after neoadjuvant chemotherapy in biopsy-proven node-positive breast cancer: the SN FNAC study

PURPOSE

An increasing proportion of patients (> 30%) with node-positive breast cancer will obtain an axillary pathologic complete response after neoadjuvant chemotherapy (NAC). If sentinel node (SN) biopsy (SNB) is accurate in this setting, completion node dissection (CND) morbidity could be avoided.

PATIENTS AND METHODS

In the prospective multicentric SN FNAC study, patients with biopsy-proven node-positive breast cancer (T0-3, N1-2) underwent both SNB and CND. Immunohistochemistry (IHC) use was mandatory, and SN metastases of any size, including isolated tumor cells (ypN0[i+], ≤ 0.2 mm), were considered positive. The optimal SNB identification rate (IR) ≥ 90% and false-negative rate (FNR) ≤ 10% were predetermined.

RESULTS

From March 2009 to December 2012, 153 patients were accrued to the study. The SNB IR was 87.6% (127 of 145; 95% CI, 82.2% to 93.0%), and the FNR was 8.4% (seven of 83; 95% CI, 2.4% to 14.4%). If SN ypN0(i+)s had been considered negative, the FNR would have increased to 13.3% (11 of 83; 95% CI, 6.0% to 20.6%). There was no correlation between size of SN metastases and rate of positive non-SNs. Using this method, 30.3% of patients could potentially avoid CND.

CONCLUSION

In biopsy-proven node-positive breast cancer after NAC, a low SNB FNR (8.4%) can be achieved with mandatory use of IHC. SN metastases of any size should be considered positive. The SNB IR was 87.6%, and in the presence of a technical failure, axillary node dissection should be performed. We recommend that SN evaluation with IHC be further evaluated before being included in future guidelines on the use of SNB after NAC in this setting.

Barriers to immediate breast reconstruction in the Canadian universal health care system

PURPOSE

To describe the population-based rates of immediate breast reconstruction (IBR) for all women undergoing mastectomy for treatment or prophylaxis of breast cancer in the past decade, and to evaluate geographic, institutional, and patient factors that influence use in the publically funded Canadian health care system.

METHODS

This population-based retrospective cohort study used administrative data that included 28,176 women who underwent mastectomy (25,141 mastectomy alone and 3,035 IBR) between April 1, 2002, and March 31, 2012, in Ontario, Canada. We evaluated factors associated with IBR by using a multivariable logistic regression model with the generalized estimating equation approach.

RESULTS

The population-based, age-adjusted IBR rate increased from 5.1 procedures to 8.7 in 100,000 adult women (43.7%; P < .001), and the increase was greatest for prophylactic mastectomy or therapeutic mastectomy for in situ breast cancer (78.6%; P < .001). Women who lived in neighborhoods with higher median income had significantly increased odds of IBR compared with mastectomy alone (odds ratio [OR], 1.71; 95% CI, 1.47 to 2.00), and immigrant women had significantly lower odds (OR, 0.59; 95% CI, 0.44 to 0.78). A patient had nearly twice the odds of receiving IBR when she was treated at a teaching hospital (OR, 1.84; 95% CI, 1.1 to 3.06) or at a hospital with two or more available plastic surgeons (OR, 2.01; 95% CI, 1.53 to 2.65). Patients who received IBR traveled significantly farther compared with those who received mastectomy alone (OR, 1.04; 95% CI, 1.02 to 1.05 for every 10 km increase).

CONCLUSION

IBR is available to select patients with favorable clinical and demographic characteristics who travel farther to undergo surgery at teaching hospitals with two or more available plastic surgeons.

Commentary on the Canadian National Breast Screening study

In the setting of the 25-year follow-up of the Canadian National Breast Screening Study, the Society of Surgical Oncology continues to endorse mammographic screening for women beginning at 40 years of age, while acknowledging that mammography has both risks and benefits. Further investigation is warranted to develop better screening methods and to determine optimal screening schedules for women based on their risk of future breast cancer and their imaging characteristics.

An Individual Person Data Meta-Analysis of Preoperative Magnetic Resonance Imaging and Breast Cancer Recurrence

Purpose

There is little consensus regarding preoperative magnetic resonance imaging (MRI) in breast cancer (BC). We examined the association between preoperative MRI and local recurrence (LR) as primary outcome, as well as distant recurrence (DR), in patients with BC.

Methods

An individual person data (IPD) meta-analysis, based on preoperative MRI studies that met predefined eligibility criteria, was performed. Survival analysis (Cox proportional hazards modeling) was used to investigate time to recurrence and to estimate the hazard ratio (HR) for MRI. We modeled the univariable association between LR (or DR) and MRI, and covariates, and fitted multivariable models to estimate adjusted HRs. Sensitivity analysis was based on women who had breast conservation with radiotherapy.

Results

Four eligible studies contributed IPD on 3,180 affected breasts in 3,169 subjects (median age, 56.2 years). Eight-year LR-free survival did not differ between the MRI (97%) and no-MRI (95%) goups (P = .87), and the multivariable model showed no significant effect of MRI on LR-free survival: HR for MRI (versus no-MRI) was 0.88 (95% CI, 0.52 to 1.51; P = .65); age, margin status, and tumor grade were associated with LR-free survival (all P < .05). HR for MRI was 0.96 (95% CI, 0.52 to 1.77; P = .90) in sensitivity analysis. Eight-year DR-free survival did not differ between the MRI (89%) and no-MRI (93%) groups (P = .37), and the multivariable model showed no significant effect of MRI on DR-free survival: HR for MRI (v no-MRI) was 1.18 (95% CI, 0.76 to 2.27; P = .48) or 1.31 (95% CI, 0.76 to 2.27; P = .34) in sensitivity analysis.

Conclusion

Preoperative MRI for staging the cancerous breast does not reduce the risk of LR or DR.

How can diagnostic assessment programs be implemented to enhance inter-professional collaborative care for cancer?

BACKGROUND

Inter-professional collaborative care (ICC) for cancer leads to multiple system, organizational, professional, and patient benefits, but is limited by numerous challenges. Empirical research on interventions that promote or enable ICC is sparse so guidance on how to achieve ICC is lacking. Research shows that ICC for diagnosis could be improved. Diagnostic assessment programs (DAPs) appear to be a promising model for enabling ICC. The purpose of this study was to explore how DAP structure and function enable ICC, and whether that may be associated with organizational and clinical outcomes.

METHODS

A case study approach will be used to explore ICC among eight DAPs that vary by type of cancer (lung, breast), academic status, and geographic region. To describe DAP function and outcomes, and gather information that will enable costing, recommendations expressed in DAP standards and clinical guidelines will be assessed through retrospective observational study. Data will be acquired from databases maintained by participating DAPs and the provincial cancer agency, and confirmed by and supplemented with review of medical records. We will conduct a pilot study to explore the feasibility of estimating the incremental cost-effectiveness ratio using person-level data from medical records and other sources. Interviews will be conducted with health professionals, staff, and referring physicians from each DAP to learn about barriers and facilitators of ICC. Qualitative methods based on a grounded approach will be used to guide sampling, data collection and analysis.

DISCUSSION

Findings may reveal opportunities for unique structures, interventions or tools that enable ICC that could be developed, implemented, and evaluated through future research. This information will serve as a formative needs assessment to identify the nature of ongoing or required improvements, which can be directly used by our decision maker collaborators, and as a framework by policy makers, cancer system managers, and DAP managers elsewhere to strategically plan for and implement diagnostic cancer services.

Abstract P1-13-14: Discordance of ER and PR status between primary and recurrent breast cancer in association with endocrine therapy

Background: Discordance in tumor receptor status between primary and recurrent tumors has been previously reported. Discordant ER/PR status has been used to differentiate recurrences from new primaries. We evaluated discordance rates of ER and PR expression between the primary and locoregional/contralateral recurrences and examined the relationship with adjuvant endocrine therapy (ET).

Methods: We conducted a retrospective chart review of breast cancer patients (pts) treated with lumpectomy and adjuvant locoregional radiation (RT) from 1999-2005 at the Princess Margaret Cancer Centre. Tumor recurrence was classified as locoregional recurrence (LRR) for ipsilateral breast or lymph node recurrence, contralateral disease (CD) or distant recurrence. ER and PR were assessed by immunohistochemistry; positive if &gt;10% tumor cells staining, borderline if 10% staining, and negative if &lt;10% staining. Univariate analyses were applied to determine the association of receptor discordance with age, menopausal status, tumor grade, endocrine therapy or adjuvant chemotherapy.

Results: All 441 pts had a lumpectomy with negative margins and RT, and had a median follow-up of 8.3 years. The median age at primary surgery was 57, and 67% of pts were postmenopausal. ET (tamoxifen and/or aromatase inhibitors) was initiated in 294 (84%) eligible patients. There were 24 (5.4%) pts with LRR, 20 (4.5%) pts with CD, and 28 (6.3%) with distant metastases. Nine pts with LRR also had distant disease, and 3 pts with CD also had distant disease. Among pts with LRR, 17 had ER/PR status available for comparison. Discordance rates for ER and PR were (1/17) 5.9% and (3/17) 17.6%, respectively, and the most common change was ER becoming positive, and PR becoming negative (75%). For pts with CD, 18 had ER/PR status available for comparison. Discordance rates for ER and PR were (7/18) 38.9% and (9/18) 50%, respectively. The most common change was ER becoming positive (86%), and PR becoming positive (75%). Distant disease receptor status was only available for two patients, therefore not included. The patient with LRR and discordant ER did not receive ET, while pts with LRR and discordant PR all received ET. Among patients with CD, 15% of patients with discordant ER status received ET, and 33% with discordant PR received ET. There was no statistically significant association between discordance rates in either LRR or CD groups and use of ET. Similarly, discordance rates were not associated with the other patient or tumor variables studied, or the development of distant metastases or death.

Conclusions: Discordance of ER and PR expression was low in LRR and higher in CD, where the majority of changes were from negative to positive receptor status. Receptor discordance was not associated with endocrine therapy. This study suggests that the biology of LRR and CD may be different, and re-evaluation of receptor status could lead to additional treatment options becoming available from an endocrine standpoint.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-13-14.

Impact of endocrine therapy in early-stage breast cancer on time to locoregional recurrence

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Background: Locoregional recurrence (LR) remains a major source of morbidity and mortality in breast cancer. Our primary aim was to evaluate the impact of endocrine therapy (ET) on time to LR. Methods: A retrospective chart review of breast cancer patients (pts) treated with lumpectomy and locoregional radiation from 1999-2005 at the Princess Margaret Cancer Centre was carried out. LR was defined as ipsilateral breast or lymph node recurrence. Kaplan-Meier estimates of survival and univariate analyses were performed for age, menopausal status, tumor and nodal stage, grade, receptor status, adjuvant chemotherapy (AC) and ET. Results: Of 440 pts evaluated, the mean age at primary resection was 56 years (yrs) (range 40-79), and 67% were postmenopausal. The majority had ductal carcinomas (87%) and grade 1-2 (68%) tumors. Tumor distribution was 315 (72%) T1, 120 (27%) T2, 4 (1%) T3; 138 (31%) were node positive. Receptor status was ER/PR+HER2- 206 (47%), ER+PR+HER2unknown 80 (18%), ER-PR-HER2unknown 41 (9%), and triple negative 37 (8%). AC was used in 190 (43%). ET (tamoxifen and/or aromatase inhibitors) was initiated in 294 (84%) eligible pts, and 267/294 (91%) completed a minimum duration of ≥2 yrs. Overall, LR occurred in 24 (5%) pts, and 8/24 (33%) pts with LR also had distant metastases. Average time from surgery to LR was 5.4 yrs (range 8 months-12 yrs). The average duration of ET in pts with LR was 4.3 yrs (range 0-8), and 5.8 yrs (range 0-12) without LR. Of ER/PR+ pts with LR, 3/15 (20%) did not receive ET. At the time of LR, 5 (33%) pts were receiving ET. After stopping ET, 2 (13%) recurred 0-2 yrs, 3 (20%) at 4-5 yrs, and 2 (13%) at 7-8 yrs. Treatment with at least 2 yrs of ET predicted for fewer recurrences: at 2 yrs LR-free rate was 100% vs 90% for <2 yrs ET; at 5 yrs 99.6% vs 84%; and at 8 yrs 98.2% vs 84% (p=0.0092). ER/PR+HER2- pts had lower LR risk (p=0.028), and ER-/PR-/HER+ had higher LR risk (p=0.029). The remaining variables were not associated with risk of LRs. Survival post-LR was 90% (95%CI 64-97%) at 2 yrs and 65% (95%CI 34-84%) at 5 yrs. Conclusions: Pts who completed at least 2 yrs of ET had significantly lower risk of LR. The average time to LR was 5.4 years, and pts with LR had decreased survival at 5 yrs post-recurrence.

Sentinel node biopsy after neoadjuvant therapy: Relevance of sentinel node micrometastases, isolated tumor cells, and value of immunohistochemistry

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Background: Sentinel node biopsy (SNB) is used in breast cancer patients that present with clinically negative nodes. In this setting, most guidelines do not support the use of immunohistochemistry (IHC) and recommend against completion node dissection (CND) when only isolated tumor cells (pN0(i+)) or micrometasases (pN1mi) are identified. When SNB is used after neoadjuvant therapy (NAT), the relevance of ypN0(i+) and ypN1mi sentinel nodes (SNs) and the value of IHC are not well established. The goals of this study are to determine if CND should be recommended in the presence of ypN0(i+) or ypN1mi SNs and if IHC should be used to evaluate SNs after NAT. Methods: From March 2009 to December 2012, 152 women with biopsy proven node positive breast cancer were accrued to the multicentric prospective SN FNAC trial. After NAT, SNB was followed by a CND in all participants. SNs were cut in serial slices no thicker than 2 mm. Hematoxylin and eosin stains (H and E) were done on all slices, and if negative, IHC was used. The size of the largest SN metastasis and the primary method of identification (H and E or IHC) were recorded. ypN0(i+), ypN1mi and ypN1 SNs were considered as positive. Pathology was centrally reviewed. Results: 145 women were eligible for the trial. Axillary pathologic complete response rate = 34% (49/145). SNB success rate = 88% (127/145). False negative rate = 8.4% (7/83). If ypN0(i+) SNs are classified as node negative, the false negative rate is increased to 13.3% (11/83). For patients with ypN0(i+) (n=7), ypN1mi (n=8) and ypN1 (n=61) SNs, the rates of non-SN involvement are 57%, 38% and 56% respectively (p=NS). 40% (27/68) of positive SNBs are primarily detected by IHC. This is increased to 64% (9/14) for the identification of SN metastases ≤ 2mm. Conclusions: After NAT, particularly when presenting with biopsy proven node positive breast cancer, patients with ypN0(i+) and ypN1mi SNs have a significant rate of non-SN involvement. In the absence of evidence to show that a CND can be safely avoided, efforts should be made to identify even minimal amounts of disease when SNBs are done following NAT. IHC is useful to increase the detection of small SN metastases in this setting. Clinical trial information: NCT00909441.

The effect of surgery type on survival and recurrence in very young women with breast cancer

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Background: Young age has been identified as an independent predictor of recurrence and mortality in women with breast cancer. The equivalence of breast conserving surgery (BCS) with mastectomy remains unclear in this population in an era of multimodal therapy. We sought to determine the effect of surgery type on the risk of recurrence and survival in a large, population based cohort of very young women. Methods: All women diagnosed with breast cancer aged ≤35 between 1994 and 2003 in Ontario were identified from the Ontario Cancer Registry, a population based registry of all incident invasive breast cancers in the province. A retrospective chart review was undertaken to identify patient, tumor and treatment variables, as well as locoregional, distant recurrences and death. Univariable and multivariable Cox proportional hazards regression models were fit to determine the effect of primary surgery type on overall survival while controlling for known confounders. To examine time to recurrence in a multivariable analysis, the proportional subdistribution hazards model (Fine and Gray) was used to account for death being a competing risk. Results: A total of 1,381 patients were identified; the median age was 33 (range 18 – 35), median follow up was 11 years. Primary surgical treatment was BCS in 793 (57%) patients of which 89% had adjuvant radiotherapy. Of the 588 (43%) having mastectomy, 53% underwent post mastectomy radiation. Overall, 38% of patients sustained a recurrence of any type and 31% had died. After controlling for tumor size, margin status, node status, grade, LVI, ER/PR, HER2 and treatment (chemotherapy, radiation, hormones) there was no difference in overall survival (HR 0.99, 95% CI 0.79,1.26) or recurrence (HR 0.96, 95% CI 0.73,1.26) among women treated with BCS or mastectomy. Predictors of recurrence were size ≥2 cm, ≥ 1 positive node, neoadjuvant chemotherapy, and lack of radiation. Predictors of death were similar and included high grade and presence of LVI. Conclusions: Very young women selected for BCS had similar outcomes to those selected for mastectomy after controlling for known prognostic factors for recurrence and death.

Sentinel node biopsy following neoadjuvant chemotherapy in biopsy proven node positive breast cancer: The SN FNAC study

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Background: A significant and increasing proportion of patients (>30%) with biopsy proven node positive breast cancer will obtain a pathological complete response (pCR) in the axilla after neoadjuvant chemotherapy (NAC). If sentinel node biopsy (SNB) can accurately identify these patients, they could potentially avoid the morbidity of an axillary node dissection. The primary aim of this study is to evaluate the identification rate (IR), false negative rate (FNR) and accuracy of SNB in this setting. The accuracy of post NAC axillary ultrasound and clinical examination are evaluated as secondary endpoints. Methods: Patients with biopsy proven node positive breast cancer (T0-3, N1-2, M0) treated with NAC were eligible to participate in this multi-centre prospective trial. Following NAC, axillary ultrasound and clinical examination results were obtained. At time of surgery, all participants underwent both a SNB and a completion node dissection. A SNB IR greater than 90% and a FNR of less than 10% were pre-determined as being optimal. Results: From September 2009 to December 2012, 153 patients were accrued to the study. 7 patients were not eligible and 5 patients had not yet undergone surgery at the time of analysis. Axillary pCR rate = 34.0% (48/141). SNB IR = 87.2% (123/141), 95% CI [81.7%-92.7%] and FNR = 9.9% (8/81), 95% CI [3.4%-16.4%]. If only one sentinel node was removed, FNR = 19.0%(4/21); if there were 2 or more sentinel nodes, FNR = 6.6% (4/61) (p < 0.0001). Accuracy of SNB, axillary ultrasound and clinical examination were 93.5%, 63.2%, and 45.5% respectively. Conclusions: SNB following NAC in biopsy proven node positive breast cancer is associated with a suboptimal IR. FNR (less than 10%) and accuracy of SNB in this study are comparable to that of patients that present with clinically negative nodes. The FNR decreases when more than one sentinel node is identified. However, in an era where regional nodal radiation is increasingly used, the relevance of leaving residual disease in the undissected axilla after NAC is unknown and remains to be investigated. Clinical trial information: NCT00909441.

Quality indicators for sentinel lymph node biopsy: is there room for improvement?

BACKGROUND

Eleven quality indicators (QI) for sentinel lymph node biopsy (SLNB) were previously developed through a consensus-based approach, yet still need to be incorporated into clinical practice. We sought to evaluate the applicability and clinical relevance for surgeons.

METHODS

Breast cancer patients undergoing SLNB between 2004 and 2008 at Mount Sinai Hospital, Toronto, were evaluated. Clinical and pathological data were obtained from an institutional database. Information on axillary recurrences was obtained through a retrospective chart review. Adherence to standardized protocols was evaluated in each case.

RESULTS

All 11 QIs were measurable in 300 patients. The identification rate was 100%. More than 1 SLN was identified in 78.6% of patients. The SLNB was performed simultaneously with primary surgery in 96.7% of patients; 61 SLNs harboured metastasis. Of these patients, 80.3% underwent completion lymphadenectomy. Cases complied with protocols for radiocolloid injection and pathologic SLN evaluation/reporting. No ineligible patients underwent SLNB. Of patients with a complete 5-year follow-up (n = 42), only 1 had axillary recurrence.

CONCLUSION

Applying QIs for SLNB was feasible, but modifications were necessary to develop a more practical approach to quality assessment. Of the 11 suggested QIs, those that encompass protocols (nuclear medicine and pathology) should be reclassified as prerequisites, as they are independent of the technical aspect of SLNB performance. The remaining 8 QIs encompass surgery per se and should be measured routinely by surgeons. Furthermore, concise and clinically relevant target rates are necessary for these QIs to be established as widely recognized control standards.

Abstract P2-10-33: Mitotic Component of Grade Can Distinguish Breast Cancer Patients at Greatest Risk of Local Relapse

Background: With the recent recognition of many different molecular subtypes of breast cancer a desire to more specifically categorize tumors to allow tailoring of treatment to individual patients has developed. This has largely involved the development of molecular tests rather than the re-examination of current pathologic criteria. We wanted to evaluate standard pathologic features to determine their ability to predict for local recurrence.

Materials and Methods: Slides were retrieved for review from 280 of 769 women who had participated in a trial of tamoxifen with or without breast irradiation between December 1992 and June 2000 and for whom outcome data up to 18 years was available. All women were 50 years of age or older at the time of enrollment and had T1 or T2 node negative breast cancer. The cases for which slides were obtained were representative of the whole group. The slides were reviewed by two breast pathologists (SJD and NAM). Several features were evaluated; modified Nottingham histologic grade and its components- degree of tubule formation, nuclear pleomorphism and mitotic count. Mitotic component of grade was calibrated to the microscopic field size used. The presence of lymphatic/vascular space invasion was also scored. A statistical analysis was performed to relate these pathologic features to local recurrence at up to 18 years.

Results: The strongest predictor of local recurrence was the mitotic component of the Nottingham histologic grade with 5.7% for mitotic score 1/3 (n = 200), 19.6% for mitotic score 2/3 (n = 37) and 19.8% for mitotic score 3/3 (n = 43)(Gray's p-value = 0.0021). Overall grade was also able to predict for local recurrence with 2.6% for Grade 1 (n = 49), 10.6% for Grade 2 (n = 162) and 17.9% for Grade 3 (n = 71)(Gray's p-value=0.026). However, neither architecture (0% vs. 9.5% vs. 9.8%, Gray's p-value=0.74) nor degree of nuclear pleomorphism (0% vs. 7.9% vs. 11.5%, Gray's p-value=0.37), the other components of histologic grade, showed a statistically significant difference for recurrence. The presence or absence of endothelial lined space invasion was also found to be not statistically different (9.3% vs. 13%, Gray's p-value=0.55).

Conclusion: Within this cohort of tamoxifen treated T1 and T2 breast cancer patients 50 years of age or older, mitotic index could stratify women into groups with high and low risk of recurrence. If validated this may be a useful way of allocating patients to different treatment groups. Additional validation studies are planned on similar groups of patients.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-10-33.