Mary Salvatore

CT Screening for Lung Cancer: Nonsolid Nodules in Baseline and Annual Repeat Rounds

PURPOSE To address the frequency of identifying nonsolid nodules, diagnosing lung cancer manifesting as such nodules, and the long-term outcome after treatment in a prospective cohort, the International Early Lung Cancer Action Program. MATERIALS AND METHODS A total of 57,496 participants underwent baseline and subsequent annual repeat computed tomographic (CT) screenings according to an institutional review board, HIPAA-compliant protocol. Informed consent was obtained. The frequency of participants with nonsolid nodules, the course of the nodule at follow-up, and the resulting diagnoses of lung cancer, treatment, and outcome are given separately for baseline and annual repeat rounds of screening. The χ(2) statistic was used to compare percentages. RESULTS A nonsolid nodule was identified in 2392 (4.2%) of 57,496 baseline screenings, and pathologic pursuit led to the diagnosis of 73 cases of adenocarcinoma. A new nonsolid nodule was identified in 485 (0.7%) of 64,677 annual repeat screenings, and 11 had a diagnosis of stage I adenocarcinoma; none were in nodules 15 mm or larger in diameter. Nonsolid nodules resolved or decreased more frequently in annual repeat than in baseline rounds (322 [66%] of 485 vs 628 [26%] of 2392, P < .0001). Treatment of the cases of lung cancer was with lobectomy in 55, bilobectomy in two, sublobar resection in 26, and radiation therapy in one. Median time to treatment was 19 months (interquartile range [IQR], 6-41 months). A solid component had developed in 22 cases prior to treatment (median transition time from nonsolid to part-solid, 25 months). The lung cancer-survival rate was 100% with median follow-up since diagnosis of 78 months (IQR, 45-122 months). CONCLUSION Nonsolid nodules of any size can be safely followed with CT at 12-month intervals to assess transition to part-solid. Surgery was 100% curative in all cases, regardless of the time to treatment.

CT Screening for Lung Cancer: Part-Solid Nodules in Baseline and Annual Repeat Rounds

OBJECTIVE The purpose of this study was to assess the frequencies of identifying participants with part-solid nodules, of diagnostic pursuit, of diagnoses of lung cancer, and long-term lung cancer survival in baseline and annual repeat rounds of CT screening in the International Early Lung Cancer Action Project. MATERIALS AND METHODS Screenings were performed under a common protocol. Participants with solid, nonsolid, and part-solid nodules and the diagnoses of lung cancer were documented. RESULTS Part-solid nodules were identified in 2892 of 57,496 (5.0%) baseline screening studies; 567 (19.6%) of these nodules resolved or decreased in size. Diagnostic pursuit led to the diagnosis of adenocarcinoma in 79 cases, all clinical stage I. At resection, one nodule (12-mm solid component) had a single N2 metastasis. A new part-solid nodule was identified in 541 of 64,677 (0.8%) annual repeat screenings; 377 (69.7%) of these nodules resolved or decreased in size. In eight cases among the 541, the diagnosis of adenocarcinoma manifesting as a part solid nodule was made; on retrospective review the nodule originally had been a nonsolid nodule. In another 20 cases, the cancer originally had manifested as a nonsolid nodule but had progressed to become part-solid at annual repeat screening before any diagnosis was pursued. These 28 annual repeat cases of lung cancer were all pathologic stage IA. Of the 107 cases of lung cancer (79 baseline cases and 28 annual repeat cases), 106 were surgically resected, and one baseline case was followed up with imaging for 4 years. The lung cancer survival rate was 100% with a median follow-up period from diagnosis of 89 months (interquartile range, 52-134 months). CONCLUSION Lung cancers manifesting as part-solid nodules at repeat screening studies all started as nonsolid nodules. Among 107 cases of adenocarcinoma manifesting as a part-solid nodule, a single lymph node metastasis was found in a single case (solid component, 12 mm).

The chest radiologist's role in invasive breast cancer detection

PURPOSE To assess the ability of chest CT to identify patients needing further evaluation of the breasts. METHODS IRB approval was obtained with a waiver of consent. Women with chest CT and mammogram within 12months formed the cohort. A breast assessment and recommendation CT score (BARCS) analogous to mammographic BI-RADS was created and compared to the mammogram BI-RADS. RESULTS BARCS and mammographic BI-RADS management recommendations were concordant for 77.1%. 11 invasive cancers were detected; all by mammogram while CT missed 2. CONCLUSION BARCS score should be studied in prospective trials. Chest CT might be the earliest opportunity to detect breast cancer.

Incremental Role of Mammography in the Evaluation of Gynecomastia in Men Who Have Undergone Chest CT

OBJECTIVE The purpose of this study was to determine whether additional breast imaging is clinically valuable in the evaluation of patients with gynecomastia incidentally observed on CT of the chest. MATERIALS AND METHODS In a retrospective analysis, 62 men were identified who had a mammographic diagnosis of gynecomastia and had also undergone CT within 8 months (median, 2 months). We compared the imaging findings of both modalities and correlated them with the clinical outcome. RESULTS Gynecomastia was statistically significantly larger on mammograms than on CT images; however, there was a high level of concordance in morphologic features and distribution of gynecomastia between mammography and CT. In only one case was gynecomastia evident on mammographic but not CT images, owing to cachexia. Two of the 62 men had ductal carcinoma, which was obscured by gynecomastia. Both of these patients had symptoms suggesting malignancy. CONCLUSION The appearance of gynecomastia on CT scans and mammograms was highly correlated. Mammography performed within 8 months of CT is unlikely to reveal cancer unless there is a suspicious clinical finding or a breast mass eccentric to the nipple. Men with clinical symptoms of gynecomastia do not need additional imaging with mammography to confirm the diagnosis if they have undergone recent cross-sectional imaging.

The general radiologist's role in breast cancer risk assessment: breast density measurement on chest CT☆

To determine if general radiologists can accurately measure breast density on low-dose chest computed tomographic (CT) scans, two board-certified radiologists with expertise in mammography and CT scan interpretation, and seven general radiologists performed retrospective review of 100 womens low-dose chest CT scans. CT breast density grade based on Breast Imaging Reporting and Data System grades was independently assigned for each case. Kappa statistic was used to compare agreement between the expert consensus grading and those of the general radiologists. Kappa statistics were 0.61-0.88 for the seven radiologists, showing substantial to excellent agreement and leading to the conclusion that general radiologists can be trained to determine breast density on chest CT.

Baseline and annual repeat rounds of screening: implications for optimal regimens of screening

AbstractObjectivesDifferences in results of baseline and subsequent annual repeat rounds provide important information for optimising the regimen of screening.MethodsA prospective cohort study of 65,374 was reviewed to examine the frequency/percentages of the largest noncalcified nodule (NCN), lung cancer cell types and Kaplan–Meier (K-M) survival rates, separately for baseline and annual rounds.ResultsOf 65,374 baseline screenings, NCNs were identified in 28,279 (43.3%); lung cancer in 737 (1.1%). Of 74,482 annual repeat screenings, new NCNs were identified in 4959 (7%); lung cancer in 179 (0.24%). Only adenocarcinoma was diagnosed in subsolid NCNs. Percentages of lung cancers by cell type were significantly different (p < 0.0001) in the baseline round compared with annual rounds, reflecting length bias, as were the ratios, reflecting lead times. Long-term K-M survival rate was 100% for typical carcinoids and for adenocarcinomas manifesting as subsolid NCNs; 85% (95% CI 81–89%) for adenocarcinoma, 74% (95% CI 63–85%) for squamous cell, 48% (95% CI 34–62%) for small cell. The rank ordering by lead time was the same as the rank ordering by survival rates.ConclusionsThe significant differences in the frequency of NCNs and frequency and aggressiveness of diagnosed cancers in baseline and annual repeat need to be recognised for an optimal regimen of screening.Key Points• Lung cancer aggressiveness varies considerably by cell type and nodule consistency. • Kaplan–Meier survival rates varied by cell type between 100% and 48%. • The percentages of lung cancers by cell type in screening rounds reflect screening biases. • Rank ordering by cell type survival is consistent with that by lead times. • Empirical evidence provides critical information for the regimen of screening.

Segmentation of the whole breast from low-dose chest CT images

The segmentation of whole breast serves as the first step towards automated breast lesion detection. It is also necessary for automatically assessing the breast density, which is considered to be an important risk factor for breast cancer. In this paper we present a fully automated algorithm to segment the whole breast in low-dose chest CT images (LDCT), which has been recommended as an annual lung cancer screening test. The automated whole breast segmentation and potential breast density readings as well as lesion detection in LDCT will provide useful information for women who have received LDCT screening, especially the ones who have not undergone mammographic screening, by providing them additional risk indicators for breast cancer with no additional radiation exposure. The two main challenges to be addressed are significant range of variations in terms of the shape and location of the breast in LDCT and the separation of pectoral muscles from the glandular tissues. The presented algorithm achieves robust whole breast segmentation using an anatomy directed rule-based method. The evaluation is performed on 20 LDCT scans by comparing the segmentation with ground truth manually annotated by a radiologist on one axial slice and two sagittal slices for each scan. The resulting average Dice coefficient is 0.880 with a standard deviation of 0.058, demonstrating that the automated segmentation algorithm achieves results consistent with manual annotations of a radiologist.

The Lung Parenchyma

The lung parenchyma should be evaluated on axial images using lung window settings (window 1500, level −500) which are recorded on the computer image. Scroll using the mouse through the right lung beginning at the apex and moving toward the lung bases evaluating the lung parenchyma in front of the right major fissure which will include the right upper and middle lobes of the lung. Next scroll from the bases of the lung to the apex reviewing the lung posterior to the right major fissure, the right lower lobe. Repeat this process reviewing the left lung parenchyma. In front of the left major fissure is the left upper lobe which includes the lingual and posterior is the left lower lobe.

The Trachea and Bronchi

Evaluation of the trachea and bronchi should be performed on lung window settings. This chapter looks at the normal anatomy of the trachea and bronchi and common anatomical variants. Next we review diseases of the trachea which can be focal such as cancer or diffuse, involving a large segment of the trachea such as amyloidosis. Bronchiectasis is irreversible dilation of the bronchi which become larger than their accompanying artery. Bronchiectasis can be focal or diffuse. Focal bronchiectasis occurs with bronchial atresia. Diffuse bronchiectasis can be central or peripheral. Central bronchiectasis is seen with allergic bronchopulmonary aspergillosis (ABPA). Distal bronchiectasis occurs in patients with infection. The distribution of the bronchiectasis helps to narrow the differential diagnosis.

The Soft Tissues

The visualized soft tissues on chest CT include the breast tissue, muscles, and subcutaneous tissue and should be viewed on mediastinal window settings on axial images (Level 40, Window 400). I recommend beginning with the right side and scrolling from superior to inferior and then left side inferior to superior. Women are having fewer mammograms currently. The indications for chest CT are increasing as lung cancer screening received approval for reimbursement by Medicare (www.Medicare.gov). Therefore, the only opportunity we may have to diagnose breast cancer early is on a CT scan of the chest. It is imperative that the scanned breast be included on the images provided to the radiologist for interpretation and they are often not included so that the field of view for evaluating the lung parenchyma is not compromised. A viable solution is to include the entire breast on soft tissue windows only and allow lung windows to be optimized for evaluation of the lung.