Olorunsola F. Agbaje

Single Reading with Computer-Aided Detection for Screening Mammography

BACKGROUND The sensitivity of screening mammography for the detection of small breast cancers is higher when the mammogram is read by two readers rather than by a single reader. We conducted a trial to determine whether the performance of a single reader using a computer-aided detection system would match the performance achieved by two readers. METHODS The trial was designed as an equivalence trial, with matched-pair comparisons between the cancer-detection rates achieved by single reading with computer-aided detection and those achieved by double reading. We randomly assigned 31,057 women undergoing routine screening by film mammography at three centers in England to double reading, single reading with computer-aided detection, or both double reading and single reading with computer-aided detection, at a ratio of 1:1:28. The primary outcome measures were the proportion of cancers detected according to regimen and the recall rates within the group receiving both reading regimens. RESULTS The proportion of cancers detected was 199 of 227 (87.7%) for double reading and 198 of 227 (87.2%) for single reading with computer-aided detection (P=0.89). The overall recall rates were 3.4% for double reading and 3.9% for single reading with computer-aided detection; the difference between the rates was small but significant (P<0.001). The estimated sensitivity, specificity, and positive predictive value for single reading with computer-aided detection were 87.2%, 96.9%, and 18.0%, respectively. The corresponding values for double reading were 87.7%, 97.4%, and 21.1%. There were no significant differences between the pathological attributes of tumors detected by single reading with computer-aided detection alone and those of tumors detected by double reading alone. CONCLUSIONS Single reading with computer-aided detection could be an alternative to double reading and could improve the rate of detection of cancer from screening mammograms read by a single reader. (ClinicalTrials.gov number, NCT00450359.)

Overdiagnosis, Sojourn Time, and Sensitivity in the Copenhagen Mammography Screening Program

Abstract:  The goal of this research was to estimate the overdiagnosis at the first and second screens of the mammography screening program in Copenhagen, Denmark. This study involves a mammography service screening program in Copenhagen, Denmark, with 35,123 women screened at least once. We fit multistate models to the screening data, including preclinical incidence of progressive cancers and nonprogressive (i.e., overdiagnosed) cancers. We estimated mean sojourn time as 2.7 years (95% confidence interval [CI] 2.2–3.1) and screening test sensitivity as 100% (95% CI 99.8–100). Overdiagnosis was estimated to be 7.8% (95% CI 0.3–26.5) at the first screen and 0.5% (95% CI 0.02–2.1) at the second screen. This corresponds to 4.8% of all cancers diagnosed among participants during the first two invitation rounds and following intervals. A modest overdiagnosis was estimated for the Copenhagen screening program, deriving almost exclusively from the first screen. The CIs were very broad, however, and estimates from larger datasets are warranted. 

Matrix Metalloproteinase Single-Nucleotide Polymorphisms and Haplotypes Predict Breast Cancer Progression

Purpose: Polymorphisms within the promoter region of several matrix metalloproteinase (MMP) genes have been linked to alterations in the level of transcription. We hypothesized that an individuals MMP genotype and haplotype will influence breast tumor progression and help predict prognosis. Experimental Design: This study has evaluated the association between single-nucleotide polymorphisms (SNP) in the promoter regions of MMP-1, MMP-3, MMP-7, MMP-9, MMP-12, and MMP-13 and metastatic spread of breast cancer in 128 lymph node–negative and 93 lymph node–positive patients. The study cohort was of mixed ethnicity, with Caucasian patients comprising 65%. Associations between genotype and lymph node status were estimated by logistic regression and with overall survival using the method of Kaplan-Meier and log-rank test. Associations between haplotype and lymph node status were also investigated. Results: The data show a significant and independent association of the C/T genotype for MMP-9 [mixed ethnicities odds ratio 3.6, 95% confidence interval (95% CI) 1.2-11.1; Caucasian odds ratio 9.1, 95% CI 1.7-48.4] and the 2G/2G genotype for MMP-1 (mixed ethnicities odds ratio 3.9, 95% CI 1.7-9.4; Caucasian odds ratio 2.6, 95% CI 1.0-6.9) with lymph node–positive disease. MMP-1 2G/2G was associated with reduced survival (hazard ratio 3.1, 95% CI 1.1-8.7), although this is dependent on lymph node status. Two haplotypes, driven by the MMP-1 2G allele, were significantly associated with lymph node–positive disease and survival. Conclusions: These results suggest that MMP single-nucleotide polymorphisms influence breast cancer behavior and that the MMP-1 2G/2G genotype increases the risk of lymph node metastasis and predicts poor prognosis.

Lymph Node Status and Breast Cancer-related Lymphedema

Objective:This study examines the association between nodal positivity and risk of developing breast cancer-related lymphedema (BCRL) in patients who underwent axillary lymph node dissection (ALND). Summary Background Data:The pathophysiology of BCRL is poorly understood. It has been assumed that one of the factors predisposing to the development of BCRL is nodal positivity, although retrospective series have produced contradictory findings. As these studies have included treatment regimens known to cause BCRL, such as axillary radiotherapy, any relationship between nodal positivity and the development of BCRL remains speculative. Methods:A total of 212 patients who had undergone ALND for invasive breast cancer had arm volume measurements preoperatively, and at intervals postoperatively. No patient received axillary radiotherapy. Arm volumes were obtained by measuring serial arm circumferences every 4 cm up the arm and then calculated by using the formula for the volume of a truncated cone. Robust regression techniques were used to analyze the effects of node positivity, age, preoperative body mass index, and wound infection on arm volume excess. Results:In all, 64 of 212 (30%) patients were node positive. Contrary to previous assumptions, positive node status was significantly inversely associated with arm volume after adjusting for tumor size, time since operation, and allowing for correlated observations within subjects. Furthermore, the number of positive nodes also correlated inversely with arm volume. Conclusion:These results are counterintuitive to the conventional understanding of the pathophysiology of BCRL. A possible explanation is that patients who develop disease in axillary lymph nodes and subsequently undergo ALND have more time and ability to develop lymphatic collaterals, which may provide adequate lymphatic drainage following surgery, thereby reducing the risk of developing BCRL.

Incorporation of a genetic factor into an epidemiologic model for prediction of individual risk of lung cancer: the Liverpool Lung Project.

The Liverpool Lung Project (LLP) has previously developed a risk model for prediction of 5-year absolute risk of lung cancer based on five epidemiologic risk factors. SEZ6L, a Met430IIe polymorphic variant found on 22q12.2 region, has been previously linked with an increased risk of lung cancer in a case-control population. In this article, we quantify the improvement in risk prediction with addition of SEZ6L to the LLP risk model. Data from 388 LLP subjects genotyped for SEZ6L single-nucleotide polymorphism (SNP) were combined with epidemiologic risk factors. Multivariable conditional logistic regression was used to predict 5-year absolute risk of lung cancer with and without this SNP. The improvement in the model associated with the SEZ6L SNP was assessed through pairwise comparison of the area under the receiver operating characteristic curve and the net reclassification improvements (NRI). The extended model showed better calibration compared with the baseline model. There was a statistically significant modest increase in the area under the receiver operating characteristic curve when SEZ6L was added into the baseline model. The NRI also revealed a statistically significant improvement of around 12% for the extended model; this improvement was better for subjects classified into the two intermediate-risk categories by the baseline model (NRI, 27%). Our results suggest that the addition of SEZ6L improved the performance of the LLP risk model, particularly for subjects whose initial absolute risks were unable to discriminate into “low-risk” or “high-risk” group. This work shows an approach to incorporate genetic biomarkers in risk models for predicting an individuals lung cancer risk. Cancer Prev Res; 3(5); 664–9. ©2010 AACR.

Long-term survival of women with basal-like ductal carcinoma in situ of the breast: a population-based cohort study

BackgroundMicroarray gene-profiling of invasive breast cancer has identified different subtypes including luminal A, luminal B, HER2-overexpressing and basal-like groups. Basal-like invasive breast cancer is associated with a worse prognosis. However, the prognosis of basal-like ductal carcinoma in situ (DCIS) is still unknown. Our aim was to study the prognosis of basal-like DCIS in a large population-based cohort.MethodsAll 458 women with a primary DCIS diagnosed between 1986 and 2004, in Uppland and Västmanland, Sweden were included. TMA blocks were constructed. To classify the DCIS tumors, we used immunohistochemical (IHC) markers (estrogen-, progesterone-, HER2, cytokeratin 5/6 and epidermal growth factor receptor) as a surrogate for the gene expression profiling. The association with prognosis was examined for basal-like DCIS and other subtypes using Kaplan-Meier survival analyses and Cox proportional hazards regression models.ResultsIHC data were complete for 392 women. Thirty-two were basal-like (8.2%), 351 were luminal or HER2-positive (89.5%) and 9 unclassified (2.3%). Seventy-six women had a local recurrence of which 34 were invasive. Another 3 women had general metastases as first event. Basal-like DCIS showed a higher risk of local recurrence and invasive recurrence 1.8 (Confidence interval (CI) 95%, 0.8-4.2) and 1.9 (0.7-5.1), respectively. However, the difference was not statistically significant. Also, no statistically significant increased risk was seen for triple-negative or high grade DCIS.ConclusionsBasal-like DCIS showed about a doubled, however not statistically significant risk for local recurrence and developing invasive cancer compared with the other molecular subtypes. Molecular subtyping was a better prognostic parameter than histopathological grade.

Incidence of bone metastases and survival after a diagnosis of bone metastases in breast cancer patients

BACKGROUND Bone is the most common metastatic site associated with breast cancer. Using a database of women with breast cancer treated at Guys Hospital, London 1976-2006 and followed until end 2010, we determined incidence of and survival after bone metastases. METHODS We calculated cumulative incidence of bone metastases considering death without prior bone metastases as a competing risk. Risk of bone metastases was modelled through Cox-regression. Survival after bone metastases diagnosis was calculated using Kaplan-Meier methodology. RESULTS Of the 7064 women, 589 (22%) developed bone metastases during 8.4 years (mean). Incidence of bone metastases was significantly higher in younger women, tumour size >5 cm, higher tumour grade, lobular carcinoma and ≥ four positive nodes, but was not affected by hormone receptor status. Median survival after bone metastases diagnosis was 2.3 years in women with bone-only metastases compared with <1 year in women with visceral and bone metastases. There was a trend for decreased survival for patients who developed visceral metastases early, and proportionately fewer patients in this group. INTERPRETATION Incidence of bone metastases has decreased but bone metastases remain a highly relevant clinical problem due to the large number of patients being diagnosed with breast cancer.

Mammographic features of breast cancers at single reading with computer-aided detection and at double reading in a large multicenter prospective trial of computer-aided detection: CADET II

PURPOSE To evaluate the mammographic features of breast cancer that favor lesion detection with single reading and computer-aided detection (CAD) or with double reading. MATERIALS AND METHODS The Computer Aided Detection Evaluation Trial II study was approved by the ethics committee, and all participants provided written informed consent. A total of 31,057 women were recruited from three screening centers between September 2006 and August 2007. They were randomly allocated to the double reading group, the single reading with CAD group, or the double reading and single reading with CAD group at a ratio of 1:1:28, respectively. In this study, cancers in the women whose mammograms were read with both single reading with CAD and double reading were retrospectively reviewed. The original mammograms were obtained for each case and reviewed by two of three experienced breast radiologists in consensus. The method of detection was noted. The size and predominant mammographic feature of the cancer were recorded, as was the breast density. CAD marking data were reviewed to determine if the cancer had been correctly marked. RESULTS A total of 227 cancers were detected in 28,204 women. A total of 170 cases were recalled with both reading regimens. Lesion types were masses (66%), microcalcifications (25%), parenchymal deformities (6%), and asymmetric densities (3%). The ability of the reading regimens to correctly prompt the reader to recall cases varied significantly by lesion type (P < .001). More parenchymal deformities were recalled with double reading, whereas more asymmetric densities were recalled with single reading with CAD. There was no difference in the ability of either reading regimen to prompt the reader to correctly recall masses or microcalcifications. CAD correctly prompted 100% of microcalcifications, 87% of mass lesions, 80% of asymmetric densities, and 50% of parenchymal deformities. CAD correctly marked 93% of spiculated masses compared with 80% of ill-defined masses (P = .054). There was a significant trend for cancers detected with double reading to occur only in women with a denser mammographic background pattern (P = .02). Size had no effect on lesion detection. CONCLUSION Readers using either single reading with CAD or double reading need to be aware of the strengths and weaknesses of reading regimens to avoid missing the more challenging cancer cases.

Age at diagnosis and distant metastasis in breast cancer--a surprising inverse relationship.

INTRODUCTION Predictors for site of distant metastasis and impact on survival in breast cancer are incompletely understood. METHODS Clinico-pathological risk factors for site of distant metastasis and survival were analysed in patients with invasive breast cancer treated between 1986 and 2006. RESULTS Of 3553 patients, with median follow-up 6.32years, 825 (23%) developed distant metastasis. The site of metastasis was bone in 196/825 (24%), viscera in 540/825 (65%) and unknown in 89 (11%). Larger primary invasive tumour size, higher tumour grade and axillary nodal positivity increased risk of metastasis to all sites. Lobular carcinoma was more likely to first metastasise to bone compared to invasive ductal carcinoma (NST). Oestrogen receptor (ER) negative, progesterone receptor (PgR) negative and/or Human epidermal growth factor (HER2) positive tumours were more likely to metastasise to viscera. A striking relationship between increasing age at diagnosis and a reduction in risk of distant metastasis to bone and viscera was observed. Median time to death from onset of metastatic disease was 1.52 (Interquartile range (IQR) 0.7-2.9)years for patients with bone metastasis and 0.7 (IQR 0.2-1.5)years for visceral metastasis. On multivariate analysis, despite the decrease in risk of distant metastasis with increasing age, there was an elevated hazard for death in patients >50years at diagnosis of metastasis if they developed bone metastasis, with a similar trend observed in the >70years age group if they developed visceral metastasis. CONCLUSION These findings indicate that there are biological mechanisms underlying the impact of age on the development of distant metastasis and subsequent death. This may have important implications in the treatment of breast cancer.

When is a completion axillary lymph node dissection necessary in the presence of a positive sentinel lymph node

BACKGROUND The management of the axilla in the presence of positive sentinel lymph node (SLN) remains controversial. Many centres forgo completion axillary lymph node dissection (cALND) in the presence of micrometastatic disease. The American College of Surgeons Oncology Group (ACOSOG) Z0011 trialists argue for extending this to macrometastasis. The aim of this study was to correlate tumour burden in SLNs with that in the residual lymph node basin to determine the likelihood of residual disease in patients with micro- and macrometastasis in the SLN. METHODS Patients who underwent cALND following a positive SLN were analysed for histopathological features of the primary tumour and burden of axillary disease. RESULTS Of 155 patients, 115 (74%) had macrometastases and 40 (26%) micrometastases in the SLNs. Residual axillary disease was detected in 55/155 (35%) patients with macrometastases and 4/40 (10%) with micrometastases. Generally, with increasing size of metastasis in the SLN there was an increasing risk of further disease in residual lymph nodes. Logistic regression analysis showed increased odds ratios for further disease for all groups when compared with the <2mm (micrometastasis) SLN group. CONCLUSION Patients may be advised to forgo cALND where the SLN contains isolated tumour cells or micrometastasis. Recommendations for proceeding to cALND can be based on the size of metastasis in the SLN, which relates to the risk of further disease in the residual axillary lymph nodes and subsequent regional recurrence.