Associations between clinical pathway concordance, cost, and survival outcomes for stage II colon cancer: a population-based study.

This study measures patient's concordance between clinical reference pathways with survival or cost among a population-based cohort of colon cancer patients applying a continuous measure of concordance. The primary hypothesis is that a higher concordance score with the clinical pathway is significantly associated with longer survival or lower cost. The study informs whether patient's adherence to a defined clinical pathway is beneficial to patients' outcomes or health system. An externally determined clinical pathway for colon cancer was used to identify treatment nodes in colon cancer care. Using observational data up to 2019, the study generated a continuous measure of pathway concordance. The study measured whether incremental improvements in pathway concordance were associated with survival and treatment costs. Concordance between patients' reference pathways and their observed trajectories of care was highly statistically associated with survivorship [hazard ratio: 0.95 (95% confidence interval, CI, 0.95-0.96)], showing that adherence to the clinical pathway was associated with a lower mortality rate. An increase in concordance was statistically significantly associated with a decrease in health system cost. When patients' care followed the clinical pathway, survival outcomes were better and total health system costs were lower in this cohort. This finding creates a compelling case for further research into understanding the barriers to pathway concordance and developing interventions to improve outcomes and help providers implement best practice care where appropriate.

Development of population-level colon cancer pathway concordance measures and association with survival.

Clinical cancer pathways help standardize healthcare delivery to optimize patient outcomes and health system costs. However, population-level measurement of concordance between standardized pathways and actual care received is lacking. Two measures of pathway concordance were developed for a simplified colon cancer pathway map for Stage II-III colon cancer patients in Ontario, Canada: a cumulative count of concordant events (CCCE) and the Levenshtein algorithm. Associations of concordance with patient survival were estimated using Cox proportional hazards models adjusted for patient characteristics and time-dependent cancer-related activities. Models were compared and the impact of including concordance scores was quantified using the likelihood ratio chi-squared test. The ability of the measures to discriminate between survivors and decedents was compared using the C-index. Normalized concordance scores were significantly associated with patient survival in models for cancer stage-a 10% increase in concordance for Stage II patients resulted in a CCCE score adjusted hazard ratio (aHR) of death of 0.93, 95% CI 0.88-0.98 and a Levenshtein score aHR of 0.64, 95% CI 0.60-0.67. A similar relationship was found for Stage III patients-a 10% increase in concordance resulted in a CCCE aHR of 0.85, 95% CI 0.81-0.88 and a Levenshtein aHR of 0.78, 95% CI, 0.74-0.81. Pathway concordance can be used as a tool for health systems to monitor deviations from established clinical pathways. The Levenshtein score better characterized differences between actual care and clinical pathways in a population, was more strongly associated with survival and demonstrated better patient discrimination.

Patient opinions on contralateral prophylactic mastectomy: A patient-driven discussion in need of tuning?

BACKGROUND: Rates of contralateral prophylactic mastectomy (CPM) are increasing among women with unilateral breast cancer despite low rates of contralateral recurrence and lack of survival benefit. We aimed to investigate the decisional needs and supports required to ensure adequate and quality decision-making by patients with breast cancer facing the decision regarding CPM. METHODS: In this qualitative study, we used semistructured interviews developed with the use of the Ottawa Decision Support Framework to investigate the decisional needs and supports of women (aged > 18 yr) with nonhereditary breast cancer who had previously discussed CPM with their care provider. Patients were recruited from 2 academic cancer centres in Toronto, Ontario. Interviews were conducted between June 2016 and October 2017. We analyzed responses to the open-ended questions iteratively and inductively to establish major themes within the results. RESULTS: Ten patients were recruited. Eight patients reported having initiated the discussion about CPM. Although most patients reported feeling supported, 6 mentioned some degree of decisional conflict. Cancer risk reduction was the most commonly reported perceived benefit of CPM (9 patients), followed by improved psychologic well-being (7). Most patients (8) did not mention the lack of survival benefit of CPM as a disadvantage of the procedure. Patients indicated that information resources (in 8 cases) and improved counselling from their health care team (in 7) would assist in decision-making. CONCLUSION: Our findings illustrate the disconnect between true and perceived risks (i.e., surgical risk) and benefits (potential recurrence and survival benefit) of CPM, which is not being managed adequately despite support from the health care team. A decision aid may address unmet patient need by providing a reliable resource regarding the benefits and risks of this procedure, while helping patients understand their values and realign their expectations.

Factors associated with waiting time to breast cancer diagnosis among symptomatic breast cancer patients: a population-based study from Ontario, Canada.

PURPOSE: A prolonged time from first presentation to cancer diagnosis has been associated with worse disease-related outcomes. This study evaluated potential determinants of a long diagnostic interval among symptomatic breast cancer patients. METHODS: This was a population-based, cross-sectional study of symptomatic breast cancer patients diagnosed in Ontario, Canada from 2007 to 2015 using administrative health data. The diagnostic interval was defined as the time from the earliest breast cancer-related healthcare encounter before diagnosis to the diagnosis date. Potential determinants of the diagnostic interval included patient, disease and usual healthcare utilization characteristics. We used multivariable quantile regression to evaluate their relationship with the diagnostic interval. We also examined differences in diagnostic interval by the frequency of encounters within the interval. RESULTS: Among 45,967 symptomatic breast cancer patients, the median diagnostic interval was 41 days (interquartile range 20-92). Longer diagnostic intervals were observed in younger patients, patients with higher burden of comorbid disease, recent immigrants to Canada, and patients with higher healthcare utilization prior to their diagnostic interval. Shorter intervals were observed in patients residing in long-term care facilities, patients with late stage disease, and patients who initially presented in an emergency department. Longer diagnostic intervals were characterized by an increased number of physician visits and breast procedures. CONCLUSIONS: The identification of groups at risk of longer diagnostic intervals provides direction for future research aimed at better understanding and improving breast cancer diagnostic pathways. Ensuring that all women receive a timely breast cancer diagnosis could improve breast cancer outcomes.

Patient-reported symptoms following mastectomy alone or lumpectomy plus radiation for early stage breast cancer: a cohort study.

PURPOSE: Studies examining symptom differences between surgeries for breast cancer patients rarely incorporate the effects of adjuvant treatment choice. We sought to understand differences in patient-reported symptoms between lumpectomy plus radiation and mastectomy in the year following surgery. METHODS: This cohort study used linked administrative datasets. The exposure was defined as lumpectomy plus radiation or mastectomy. The outcomes of moderate-to-severe (score ≥ 4) patient-reported symptoms were obtained using the Edmonton symptom assessment system (ESAS). Line plots were created to determine symptom trajectories in the 12 months following surgery, and the relationships between surgery and each of the nine symptoms were assessed using multivariable analyses. Clinical significance was determined as a difference of 10%. RESULTS: Of 13,865 Stage I-II breast cancer patients diagnosed 2007-2015, 11,497 underwent lumpectomy plus radiation and 2368 underwent mastectomy. Symptom trajectories were similar for all nine symptoms until approximately 5 months postoperatively when they diverged and mastectomy symptoms started becoming more severe. On multivariable analyses, patients undergoing mastectomy were at an increased risk of reporting moderate-to-severe depression (RR 1.19, 95% CI 1.09-1.30), lack of appetite (RR 1.11, 95% CI 1.03-1.20), and shortness of breath (RR 1.16, 95% CI 1.04-1.15) compared to those undergoing lumpectomy plus radiation. CONCLUSIONS: Even with the addition of adjuvant radiation, patients who are treated with lumpectomy fare better in three of nine patient-reported symptoms. Further examination of these differences will assist in better shared decision-making regarding surgical treatments.

Practitioner Opinion on Contralateral Prophylactic Mastectomy: How Do We Steer a Patient-Driven Discussion?

BACKGROUND: Contralateral prophylactic mastectomy (CPM) is increasing despite a recent statement from The American Society of Breast Surgeons discouraging average-risk women with unilateral breast cancer (BC) from undergoing CPM. The objective of our study was to conduct a needs assessment of BC health practitioners to gather information about their opinions, attitudes, and experiences surrounding CPM. METHODS: The Ottawa Decision Support Framework was the theoretical framework for the development of the interview guide. Semistructured interviews were conducted until data saturation with a convenience sample of 16 BC practitioners (Ontario, Canada), including oncologic and reconstructive surgeons, medical oncologists, and nurse navigators. RESULTS: Nearly all practitioners identified the discussion regarding CPM as patient-initiated. The majority of practitioners (13/16) described their role as supporting the patient in the decision-making process. Practitioners described educating patients on the lack of survival benefit and in general discouraging CPM. Practitioners agreed that most patients demonstrate decisional conflict (11/16) as a barrier to decision-making, and it is a challenge to realign patients' understanding and expectations. Almost all practitioners (15/16) identified a need for information materials to help educate patients on the risks and benefits of CPM and to help realign expectations. CONCLUSIONS: Practitioners have identified CPM in average-risk women with unilateral BC as a patient-driven phenomenon that is on the rise, despite highlighting the increased risk of complications and lack of survival benefit. Our practitioner needs assessment identifies the need for a dynamic decision aid to help guide the shared decision-making process for practitioners and patients.

Axillary Lymph Node Ultrasound Following Neoadjuvant Chemotherapy in Biopsy-Proven Node-Positive Breast Cancer: Results from the SN FNAC Study.

BACKGROUND: The sentinel node biopsy following neoadjuvant chemotherapy (SN FNAC) study has shown that in node-positive (N+) breast cancer, sentinel node biopsy (SNB) can be performed following neoadjuvant chemotherapy (NAC), with a low false negative rate (FNR = 8.4%). A secondary endpoint of the SN FNAC study was to determine whether axillary ultrasound (AxUS) could predict axillary pathological complete response (ypN0) and increase the accuracy of SNB. METHODS: The SN FNAC trial is a study of patients with biopsy-proven N+ breast cancer who underwent SNB followed by completion node dissection. All patients had AxUS following NAC and the axillary nodes were classified as either positive (AxUS+) or negative (AxUS-). AxUS was compared with the final axillary pathology results. RESULTS: There was no statistical difference in the baseline characteristics of patients with AxUS+ versus those with AxUS-. Overall, 82.5% (47/57) of AxUS+ patients had residual positive lymph nodes (ypN+) at surgery and 53.8% (42/78) of AxUS- patients had ypN+. Post NAC AxUS sensitivity was 52.8%, specificity 78.3%, and negative predictive value 46.2%. AxUS FNR was 47.2%, versus 8.4% for SNB. If post-NAC AxUS- was used to select patients for SNB, FNR would decrease from 8.4 to 2.7%. However, using post-NAC AxUS in addition to SNB as an indication for ALND would have led to unnecessary ALND in 7.8% of all patients. CONCLUSION: AxUS is not appropriate as a standalone staging procedure, and SNB itself is sufficient to assess the axilla post NAC in patients who present with N+ breast cancer.

Breast screening for survivors of breast cancer: A systematic review.

There is a large and growing population of women who have a personal history of breast cancer (PHBC). This systematic review was undertaken to explore the outcomes of surveillance mammography in breast cancer survivors, and to examine the evidence for screening these women within an organized population-based screening program. We searched Cochrane Central Register of Controlled Trials (CENTRAL Issue 6, 2015), OVID MEDLINE and EMBASE (January 2012 to June 22, 2015) for English-language studies of surveillance of the target population. A study author extracted study outcomes, which were audited by a research assistant. One systematic review and 5 primary studies were included. These showed that surveillance mammography may reduce breast cancer-specific mortality through early/asymptomatic detection (Hazard Ratio for those without compared to with symptoms:HR: 0.64, 95% CI 0.55 - 0.74). Three studies showed that semi-annual mammography is likely not of greater benefit than annual mammography. No evidence was found to suggest that surveillance mammography for women with a PHBC should not be conducted within an organized screening program. The small evidence-base had a high level of heterogeneity in populations, interventions and outcomes. Based on this review, organized screening programs should reassess their guidelines on surveillance mammography and consider including women with a PHBC.

Whole-mount pathology of breast lumpectomy specimens improves detection of tumour margins and focality.

AIMS: Technical limitations in conventional pathological evaluation of breast lumpectomy specimens may reduce diagnostic accuracy in the assessment of margin and focality. A novel technique based on whole-mount serial sections enhances sampling while preserving specimen conformation and orientation. The aim of this study was to investigate assessment of focality and margin status by the use of whole-mount serial sections versus simulated conventional sections in lumpectomies. METHODS AND RESULTS: Two pathologists interpreted whole-mount serial sections and simulated conventional sections for 58 lumpectomy specimens by reporting the closest margin and focality. Measurements were compared by the use of McNemar's chi-squared test. Statistically significant differences were observed in the assignment of both margin positivity (P = 0.014) and multifocality (P = 0.021). A positive margin or multifocal disease was identified by the use of whole-mount serial sections but missed in the simulated conventional assessment in 10.3% and 17.2% of all cases, respectively. There was no case in which a positive margin was detected only in the simulated conventional assessment. CONCLUSIONS: The whole-mount technique is more sensitive than conventional assessment for identifying a positive margin or multifocal disease in breast lumpectomy specimens. Undersampling in conventional sections was implicated in almost all cases of discordance. The majority of positive margins or secondary foci identified only in whole-mount serial sections concerned in-situ disease.

Utilization of Percutaneous Needle Biopsy for Breast Diagnosis in a Comprehensive Breast Center: Implications for Development of Quality Indicators.

INTRODUCTION: Percutaneous needle biopsy (PNB) is the standard of care for diagnosis of breast lesions. Rates of excisional biopsy for breast diagnosis in North America have been reported at approximately 35 %, although significant regional variation exists. A target rate of PNB for diagnosis of breast abnormalities is needed to facilitate quality improvement. We sought to describe the use of PNB in a referral practice, the clinical scenarios prompting PNB or surgical biopsy (SB), and the accuracy and rate of PNB to inform the ultimate development of a benchmark rate of PNB in breast diagnosis. MATERIALS AND METHODS: Female patients age 18-90 years, referred to Sunnybrook Health Sciences Centre, a large teaching hospital affiliated with the University of Toronto, with a breast lesion prompting tissue diagnosis with SB and/or PNB between 2002 and 2009 were studied. Each biopsied lesion was characterized by method of biopsy: PNB, SB, or PNB followed by SB. For each lesion, we collected data on patient demographics and breast cancer risk, reason for referral, imaging characteristics (breast imaging-reporting and data system classification, full description, final impression before biopsy), and pathology from each biopsy method. We report concordance between the final impression pre-biopsy and the PNB diagnosis with final surgical diagnosis where applicable. RESULTS: One thousand and twenty-six lesions were biopsied, 987 (96 %) with PNB. The benign:malignant ratio for the entire cohort was 1.2:1. Final impression was concordant with final pathology in 674/862 (78 %) and PNB diagnosis was concordant with SB pathology in 487/556 (88 %). The reasons for SB without PNB were required pathologic evaluation of the entire lesion (n = 19), patient choice (n = 5), other biopsy technique used (n = 6), technical (n = 4), planned mastectomy (n = 3), and enlarging mass (n = 2). 155/559 (28 %) of lesions without evidence of malignancy on PNB ultimately underwent SB. Papillary lesions and radial scars were more likely to undergo SB with or without prior PNB. Lesions deemed to be suspicious or malignant on final impression were more likely to be excised after a benign diagnosis at PNB. CONCLUSION: The vast majority of lesions requiring tissue diagnosis can be accurately diagnosed with PNB. Benchmarks for rates of PNB of 90 % or greater may be considered for performance measurement in appropriate populations.

A Patient-Centered Approach to Wait Times in the Surgical Management of Breast Cancer in the Province of Ontario.

BACKGROUND: Wait time for breast cancer is an important contributor to cancer outcomes and patient satisfaction. This study sought to define a patient-centered wait time by measuring the time from the first abnormal imaging to definitive surgery. The authors hypothesized that multiple preoperative investigations significantly increase the patient-centered wait time. METHODS: A retrospective analysis of prospectively maintained databases at the Institute for Clinical and Evaluative Sciences in Ontario, Canada was performed. Women undergoing primary surgery for invasive breast cancer from 2003 to 2011 were evaluated. The median wait time between the first abnormal imaging and definitive surgery was calculated. Uni- and multivariable analyses were performed to identify characteristics of the patients, treating institution, and diagnostic pathway that contribute significantly to the patient-centered wait time. RESULTS: Our final cohort consisted of 42,179 patients: 31,837 (75 %) who had breast conserving surgery and 10,342 (25 %) who underwent mastectomy. The median wait time from the first abnormal imaging to definitive surgery was 52 days (intraquartile range 35-76 days). In adjusted analysis, older patient age, later year of surgery, additional preoperative imaging, and biopsies beyond those required for diagnosis significantly and independently extended the surgical wait time. Preoperative consultations and institutional factors such as volume of breast surgery performed and geographic location also independently had an impact on surgical wait time. CONCLUSIONS: This study defined a novel patient-centered measure of surgical wait time that more fully embraces the wait experienced by the patient. Many common preoperative interventions had a significant impact on overall wait time experienced by the patient. Evidence-based quality initiatives to coordinate appropriate investigations are needed to reduce wait times.

Digital compared to screen-film mammography: breast cancer prognostic features in an organized screening program.

Our previous study found cancer detection rates were equivalent for direct radiography compared to screen-film mammography, while rates for computed radiography were significantly lower. This study compares prognostic features of invasive breast cancers by type of mammography. Approved by the University of Toronto Research Ethics Board, this study identified invasive breast cancers diagnosed among concurrent cohorts of women aged 50-74 screened by direct radiography, computed radiography, or screen-film mammography from January 1, 2008 to December 31, 2009. During the study period, 816,232 mammograms were performed on 668,418 women, and 3,323 invasive breast cancers were diagnosed. Of 2,642 eligible women contacted, 2,041 participated (77.3 %). The final sample size for analysis included 1,405 screen-detected and 418 interval cancers (diagnosed within 24 months of a negative screening mammogram). Polytomous logistic regression was performed to evaluate the association between tumour characteristics and type of mammography, and between tumour characteristics and detection method. Odds ratios (OR) and 95 % confidence intervals (CI) were recorded. Cancers detected by computed radiography compared to screen-film mammography were significantly more likely to be lymph node positive (OR 1.94, 95 %CI 1.01-3.73) and have higher stage (II:I, OR 2.14, 95 %CI 1.11-4.13 and III/IV:I, OR 2.97, 95 %CI 1.02-8.59). Compared to screen-film mammography, significantly more cancers detected by direct radiography (OR 1.64, 95 %CI 1.12-2.38) were lymph node positive. Interval cancers had worse prognostic features compared to screen-detected cancers, irrespective of mammography type. Screening with computed radiography may lead to the detection of cancers with a less favourable stage distribution compared to screen-film mammography that may reflect a delayed diagnosis. Screening programs should re-evaluate their use of computed radiography for breast screening.

Surgical resident experience in breast disease: a national study.

BACKGROUND: Management of breast disease is an integral component of general surgery. This study was performed to describe the exposure to breast disease by residents in Canadian general surgery programs. METHODS: This study involved a 20-item survey and pilot semistructured interviews. Surgical trainees at 12 training programs in Canada participated in the survey. Results were used to characterize resident experience with breast surgery and clinics. RESULTS: Residents across all post-graduate training years and from 12 Canadian medical schools responded (n = 162, 44 %). Residents had the most breast surgery experience in PGY2 and PGY3 years. One third of trainees performed ≤ 1 breast procedure per month. Only 25 % had attended more than one breast clinic per month. Lumpectomies were the most common procedure (20.7/year) and 94 % of residents performed sentinel lymph node biopsy. Four pilot semistructured interviews were performed. The greatest stated barriers to breast training were "lack of time" and the impression that these were "lower priority cases." CONCLUSIONS: Achieving competence in breast disease management is a key requirement for general surgery trainees. Surgical educators must ensure that the quality and quantity of residency training in breast diseases is sufficient for future surgeons to provide optimal patient care.

The effect of age on the opportunity to receive cancer treatment.

INTRODUCTION: Older adults with cancer may not receive the same opportunities for treatment as younger patients. In this retrospective population-based cohort study, we explored whether age was an independent predictor of receiving specialist consultation and treatment. METHODS: Patients age 45-99 were identified from the Ontario Cancer Registry having a primary solid tumor diagnosed between 01/Jan/2010 and 31/Dec/2019. We used logistic regression adjusted sociodemographic and clinical characteristics to compare the likelihood of consultation or receipt of treatment using linear splines at critical ages of 65, 80, and 90 years. RESULTS: A total 168,232 (42%), 165,205 (41%), 57,360 (14%), and 7810 (2%) patients were diagnosed age 45-64, 65-79, 80-89, and 90-99, respectively. The likelihood of surgical consultation decreased as patients reached 65 years [adjusted odds ratio (aOR) 0.86 (0.84-0.89)], which decreased further among octogenarians [aOR 0.63 (0.59-0.67)]. Similar results were observed for consultation with a medical oncologist and radiation oncologist. Receipt of surgery also decreased with age. Three-month post-operative mortality was higher among older patients [aRR 1.38 (1.26-1.50) per 10 years, p < 0.0001], an effect that remained similar as patients reached age 65 + years of age (p = 0.09 for change). For stage I patients, 3-month post-operative survival was high across all age groups, ranging from 99.8% in 45-64 year-olds, 99.4% in 65-79 year-olds, and 98.1% among octogenarians and nonagenarians (lung, colorectal, breast, cervical cancer patients). CONCLUSION: Older patients were less likely to have specialist consultations. More comprehensive data collection on clinical factors and referral patterns is needed to improve care for elderly cancer patients.

Identifying Breast Cancer Recurrence in Administrative Data: Algorithm Development and Validation.

Breast cancer recurrence is an important outcome for patients and healthcare systems, but it is not routinely reported in cancer registries. We developed an algorithm to identify patients who experienced recurrence or a second case of primary breast cancer (combined as a "second breast cancer event") using administrative data from the population of Ontario, Canada. A retrospective cohort study design was used including patients diagnosed with stage 0-III breast cancer in the Ontario Cancer Registry between 1 January 2009 and 31 December 2012 and alive six months post-diagnosis. We applied the algorithm to healthcare utilization data from six months post-diagnosis until death or 31 December 2013, whichever came first. We validated the algorithm's diagnostic accuracy against a manual patient record review (n = 2245 patients). The algorithm had a sensitivity of 85%, a specificity of 94%, a positive predictive value of 67%, a negative predictive value of 98%, an accuracy of 93%, a kappa value of 71%, and a prevalence-adjusted bias-adjusted kappa value of 85%. The second breast cancer event rate was 16.5% according to the algorithm and 13.0% according to manual review. Our algorithm's performance was comparable to previously published algorithms and is sufficient for healthcare system monitoring. Administrative data from a population can, therefore, be interpreted using new methods to identify new outcome measures.

Differences in breast cancer diagnosis by patient presentation in Ontario: a retrospective cohort study.

BACKGROUND: In Ontario, patients with breast cancer typically receive their diagnoses through the Ontario Breast Screening Program (OBSP) after an abnormal screen, through screening initiated by a primary care provider or other referring physician, or through follow-up of symptoms by patients' primary care providers. We sought to explore the association of the route to diagnosis (screening within or outside the OBSP or via symptomatic presentation) with use of OBSP-affiliated breast assessment sites (O-BAS), wait times until diagnosis or treatment, health care use and overall survival for patients with breast cancer. METHODS: In this retrospective cohort study, we used the Ontario Cancer Registry to identify adults (aged 18-105 yr) who received a diagnosis of breast cancer from 2013 to 2017. We excluded patients if they were not Ontario residents or had missing age or sex, or who died before diagnosis. We used logistic regression to evaluate factors associated with categorical variables (whether patients were or were not referred to an OBAS, whether patients were screened or symptomatic) and Cox proportional hazards regression to identify factors associated with all-cause mortality. RESULTS: Of 51 460 patients with breast cancer, 42 598 (83%) received their diagnoses at an O-BAS. Patients whose cancer was first detected through the OBSP were more likely than symptomatic patients to be given a diagnosis at an O-BAS (adjusted odds ratio 1.68, 95% confidence interval [CI] 1.57 to 1.80). Patients screened by the OBSP were given their diagnoses 1 month earlier than symptomatic patients, but diagnosis at an O-BAS did not affect the time until either diagnosis or treatment. Patients referred to an O-BAS had significantly better overall survival than those who were not referred (adjusted hazard ratio 0.73, 95% CI 0.66 to 0.80). INTERPRETATION: Patients screened through the OBSP were given their diagnoses earlier than symptomatic patients and were more likely to be referred to an O-BAS, which was associated with better survival. Our findings suggest that individuals with signs and symptoms of breast cancer would benefit from similar referral processes, oversight and standards to those used by the OBSP.

Measuring the quality of sentinel lymph node biopsy in breast cancer using newly developed quality indicators: a feasibility study.

BACKGROUND: Measurement of the quality of sentinel lymph node biopsy (SLNB) has not been reported beyond the false-negative rate and sentinel lymph node identification rate. This study's purpose is to determine the feasibility of measuring 11 quality indicators (QIs) that were recently developed using a modified Delphi process. METHODS: All patients who underwent SLNB for breast cancer at a tertiary health-care center from January 1st 2005 to December 31st 2007 were identified using a SLNB registry. Patient charts were reviewed retrospectively and the QIs were abstracted. RESULTS: Nine of the 11 QIs were measurable: 7 required chart-level abstraction, 2 were confirmed at an institutional level, and 2 were immeasurable due to registry limitations. Of the 497 identified patients, 13 patients had failed SLNB, resulting in 484 SLNBs. The axillary positivity rate was 19%. The method of SLN identification was reported in 97% of cases, and in 388 (80%) more than one SLN was removed. All SLNs were serially sectioned according to protocol, though only 102 (21%) of pathology reports explicitly stated the cancer stage. Nearly all SLNBs were performed alongside the primary breast surgery. Among SLN-positive patients: 78 (87%) underwent axillary lymph node dissection, 10 patients refused, and chart data were missing in 2 others. No "ineligible" patients had SLNB. CONCLUSION: Measurement of newly developed QIs for SLNB is feasible for abstraction from inpatient charts at a single institution. These QIs can provide baseline measures for ongoing quality assessment of SLNB using hospital chart review.

Development and evaluation of a robust algorithm for computer-assisted detection of sentinel lymph node micrometastases.

AIMS: Increasing the sectioning rate for breast sentinel lymph nodes can increase the likelihood of detecting micrometastases. To make serial sectioning feasible, we have developed an algorithm for computer-assisted detection (CAD) with digitized lymph node sections. METHODS AND RESULTS: K-means clustering assigned image pixels to one of four areas in a colourspace (representing tumour, unstained background, counterstained background and microtomy artefacts). Four filters then removed 'false-positive' pixels from the tumour cluster. A set of 43 sections containing tumour (a total of 259 foci) and 59 sections negative for malignancy was defined by two pathologists, using light microscopy, and CAD was applied. For the clinically relevant task of identifying the largest focus in each section (micrometastasis in 22/43 sections), the sensitivity and specificity were 100%. Isolated tumour cells (ITCs) were identified in one slide initially considered to be negative. Identification of all 259 foci yielded sensitivities of 57.5% for ITCs (<0.200 mm), 89.5% for micrometastases, and 100% for larger metastases, with one false-positive. Reduced sensitivity was ascribed to variable staining. Nine additional metastases (<0.01-0.3 mm) that were not initially identified were detected by CAD. CONCLUSIONS: This algorithm is well suited to the task of sentinel lymph node evaluation and may enhance the detection of occult micrometastases.

Supine breast MRI.

PURPOSE: To achieve high-quality unilateral supine breast magnetic resonance imaging (MRI) as a step to facilitate image aiding of clinical applications, which are often performed in the supine position. Contrast-enhanced breast MRI is a powerful tool for the diagnosis of cancer. However, prone patient positioning typically used for breast MRI hinders its use for image aiding. MATERIALS AND METHODS: A fixture and a flexible four-element receive coil were designed for patient-specific shaping and placement of the coil in close conformity to the supine breast. A 3D spoiled gradient sequence was modified to incorporate compensation of respiratory motion. The entire setup was tested in volunteer experiments and in a pilot patient study. RESULTS: The flexible coil design and the motion compensation produced supine breast MR images of high diagnostic value. Variations in breast shape and in tissue morphology within the breast were observed between a supine and a diagnostic prone MRI of a patient. CONCLUSION: The presented supine breast MRI achieved an image quality comparable to diagnostic breast MRI. Since supine positioning is common in many clinical applications such as ultrasound-guided breast biopsy or breast-conserving surgery, the registration of the supine images will aid these applications.

Variation in Diagnosis, Treatment, and Outcome of Esophageal Cancer in a Regionalized Care System in Ontario, Canada.

Importance: Esophageal cancer remains one of the most deadly cancers, ranking sixth highest among cancers leading to the greatest years of life lost. Objective: To determine how patients with esophageal cancer are diagnosed and treated in Ontario's regionalized thoracic surgery centers. Design, Setting, and Participants: This cohort study included patients diagnosed with esophageal cancer between January 1, 2010, and December 31, 2018, identified from the Ontario Cancer Registry, in a single-payer health care system with regionalization of thoracic surgery in the province of Ontario, Canada. Exposures: Exposures included incidence of esophageal cancer and stage at diagnosis; time from the first health care visit until treatment; and the use of specialist consultations, endoscopic ultrasonography, positron emission tomography and computed tomography, endomucosal resection, esophagectomy, neoadjuvant therapy, adjuvant therapy, radiation alone, and chemotherapy alone or in combination with other treatment. Main Outcomes and Measures: Outcome measures included wait times, health care use, treatment, and overall survival. Data were analyzed from March 2020 to February 2021. Results: There were 10 364 patients (mean [SD] age, 68.3 [11.9] years; 7876 men [76%]) identified during the study period. The incidence of esophageal cancer increased over the study period from 1041 in 2010 to 1309 in 2018, which was driven by a 30% increase in the number of adenocarcinomas. The time from first health care encounter to start of treatment was a median 93 days (interquartile range, 56-159 days). Endoscopic ultrasonography was observed for 12% of patients, and positron emission tomography and computed tomography (CT) in 45%. Use of endoscopic mucosal resection was observed for 8% of patients with stage 0 to I disease. A total of 114 of 547 patients (21%) receiving endoscopic resection had a subsequent esophagectomy. Only 2778 patients (27%) had consultations with a thoracic surgeon, a medical oncologist, and a radiation oncologist, whereas 1514 patients (15%) did not see any of these specialists. Of 3047 patients who had an esophagectomy, those receiving neoadjuvant therapy had better overall survival (median survival, 36 months; 95% CI, 32-39 months) than patients who received esophagectomy alone (median survival, 27 months; 95% CI, 24-30 months) or those who received esophagectomy with adjuvant therapy (median survival, 36 months; 95% CI, 32-44 months) despite significant early mortality (log-rank P < .001). There was significant variation in treatment modality across hospitals: esophagectomy ranged from 5% to 39%; esophagectomy after neoadjuvant therapy ranged from 33% to 93%; and esophagectomy followed by adjuvant therapy ranged from 0 to 34% (P < .001). Perioperative mortality was higher at 30 days for patients receiving esophagectomy at low-volume centers (odds ratio [OR], 3.66; 95% CI, 2.01-6.66) and medium-volume centers (OR, 2.07; 95% CI, 1.33-3.23) compared with high-volume centers (P < .001). A longer wait time until treatment was associated with better overall survival (median overall survival was 15 to 17 days vs 5 to 8 days for patients who received treatment earlier than 30 days vs 30 days or longer after diagnosis; P < .001). Conclusions and Relevance: The results of this cohort study suggest that despite regionalization, there was significant regional variability in volumes at designated centers and in the evaluation and treatment course for patients with esophageal cancer across Ontario.