Accuracy of chest film screening by technologists in the New York early lung cancer detection program

The Role of Genomics and Proteomics in Lung Cancer Early Detection and Treatment

Lung cancer is the leading cause of cancer-related death worldwide, with non-small-cell lung cancer (NSCLC) being the primary type. Unfortunately, it is often diagnosed at advanced stages, when therapy leaves patients with a dismal prognosis. Despite the advances in genomics and proteomics in the past decade, leading to progress in developing tools for early diagnosis, targeted therapies have shown promising results; however, the 5-year survival of NSCLC patients is only about 15%. Low-dose computed tomography or chest X-ray are the main types of screening tools. Lung cancer patients without specific, actionable mutations are currently treated with conventional therapies, such as platinum-based chemotherapy; however, resistances and relapses often occur in these patients. More noninvasive, inexpensive, and safer diagnostic methods based on novel biomarkers for NSCLC are of paramount importance. In the current review, we summarize genomic and proteomic biomarkers utilized for the early detection and treatment of NSCLC. We further discuss future opportunities to improve biomarkers for early detection and the effective treatment of NSCLC.

Chest X-ray Interpretation by Radiographers Is Not Inferior to Radiologists: A Multireader, Multicase Comparison Using JAFROC (Jack-knife Alternative Free-response Receiver Operating Characteristics) Analysis

RATIONALE AND OBJECTIVES

Chest X-rays (CXR) are one of the most frequently requested imaging examinations and are fundamental to many patient pathways. The aim of this study was to investigate the diagnostic accuracy of CXR interpretation by reporting radiographers (technologists).

METHODS

A cohort of consultant radiologists (n = 10) and reporting radiographers (technologists; n = 11) interpreted a bank (n = 106) of adult CXRs that contained a range of pathologies. Jack-knife alternate free-response receiver operating characteristic (JAFROC) methodology was used to determine the performance of the observers (JAFROC v4.2). A noninferiority approach was used, with a predefined margin of clinical insignificance of 10% of average consultant radiologist diagnostic accuracy.

RESULTS

The diagnostic accuracy of the reporting radiographers (figure of merit = 0.828, 95% confidence interval 0.808-0.847) was noninferior to the consultant radiologists (figure of merit = 0.788, 95% confidence interval 0.766-0.811), P < .0001.

CONCLUSIONS

With appropriate postgraduate education, reporting radiographers are able to interpret CXRs at a level comparable to consultant radiologists.

Immediate reporting of chest X-rays referred from general practice by reporting radiographers: a single centre feasibility study

Aim

To investigate the feasibility of radiographer-led immediate reporting of chest radiographs (CXRs) referred from general practice.

Materials and methods

This 4-month feasibility study (November 2016 to March 2017) was carried out in a single radiology department at an acute general hospital. Comparison was made between CXRs that received an immediate and routine report to determine the number of lung cancers diagnosed, time to diagnosis of lung cancer, time to computed tomography (CT), and number of urgent referrals to respiratory medicine.

Results

Forty of 186 sessions (22%) were covered by radiographer immediate reporting. Of the 1,687 CXRs referred from general practice, 558 (33.1%) received an immediate report (radiographer or radiologist). Twenty-two (of 36) CT examinations performed were following an abnormal CXR with an immediate report (mean 0.8 scans/week). Time from CXR to CT was shorter in the immediate report group (n=22 mean 0.9 days SD=2.3) compared to routine reporting (n=14; mean 6.5 SD=3.2; F=27.883, p<0.0001). Time to multidisciplinary team (MDT) discussion was shorter in the immediate reporting group (mean 4.1 SD=2.9) compared to routine reporting (mean 10.6; SD=4.5; F=11.59, p<0.0001). No apparent difference was found for time to discussion at treatment MDT.

Conclusion

It is feasible to introduce a radiographer-led immediate CXR reporting service. Patients can be taken off the lung cancer pathway sooner with the introduction of radiographer immediate reporting of CXRs and this may improve outcomes for patients. A definitive study assessing outcomes is required to determine whether this will have an impact mortality and morbidity for patients.

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Early lung cancer diagnosis is often limited by insufficient radiology capacity.

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It is feasible to introduce immediate reporting of chest X-rays from general practice by radiographers.

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Time to diagnosis of lung cancer can be significantly shortened with immediate chest X-ray reporting.

Computing eye gaze metrics for the automatic assessment of radiographer performance during X-ray image interpretation

AIM

To investigate image interpretation performance by diagnostic radiography students, diagnostic radiographers and reporting radiographers by computing eye gaze metrics using eye tracking technology.

METHODS

Three groups of participants were studied during their interpretation of 8 digital radiographic images including the axial and appendicular skeleton, and chest (prevalence of normal images was 12.5%). A total of 464 image interpretations were collected. Participants consisted of 21 radiography students, 19 qualified radiographers and 18 qualified reporting radiographers who were further qualified to report on the musculoskeletal (MSK) system.

OUTCOME MEASURES

Eye tracking data was collected using the Tobii X60 eye tracker and subsequently eye gaze metrics were computed. Voice recordings, confidence levels and diagnoses provided a clear demonstration of the image interpretation and the cognitive processes undertaken by each participant. A questionnaire afforded the participants an opportunity to offer information on their experience in image interpretation and their opinion on the eye tracking technology.

RESULTS

Reporting radiographers demonstrated a 15% greater accuracy rate (p≤0.001), were more confident (p≤0.001) and took a mean of 2.4s longer to clinically decide on all features compared to students. Reporting radiographers also had a 15% greater accuracy rate (p≤0.001), were more confident (p≤0.001) and took longer to clinically decide on an image diagnosis (p=0.02) than radiographers. Reporting radiographers had a greater mean fixation duration (p=0.01), mean fixation count (p=0.04) and mean visit count (p=0.04) within the areas of pathology compared to students. Eye tracking patterns, presented within heat maps, were a good reflection of group expertise and search strategies. Eye gaze metrics such as time to first fixate, fixation count, fixation duration and visit count within the areas of pathology were indicative of the radiographer's competency.

CONCLUSION

The accuracy and confidence of each group could be reflected in the variability of their eye tracking heat maps. Participants' thoughts and decisions were quantified using the eye tracking data. Eye tracking metrics also reflected the different search strategies that each group of participants adopted during their image interpretations. This is the first study to use eye tracking technology to assess image interpretation skills between various groups of different levels of experience in radiography, especially on a combination of the MSK system, chest cavity and a variety of pathologies.

Effect of Training and Experience on Radiologic Diagnostic Performance in Midfacial Trauma

In a retrospective approach the medical records and radiographs of 618 patients with midfacial trauma were reviewed by radiologists who were classified into four groups according to the length of their training and experience. Initially reported diagnoses were compared with discharge diagnoses, and the impact of training and experience on diagnostic performance was assessed. The same parameters were also investigated in a prospective study. Neither of the investigations revealed any statistically significant improvement in diagnostic performance with increased training and experience. After the basic radiologic education, innate perceptive and cognitive abilities seem to have a larger influence on radiologic diagnostic preformance than training and experience.

Modeling excess lung cancer risk among screened arm participants in the Mayo Lung Project

BACKGROUND

The Mayo Lung Project (MLP) was a randomized clinical trial designed to test whether periodic screening by chest x-ray reduced lung cancer (LC) mortality in men who were high-risk smokers. Among MLP participants, there were more deaths from LC in the screening arm both at the trial's end and after long-term follow-up. Overdiagnosis was cited widely as an explanation for the MLP results, whereas a role for excess LC risk attributable to undergoing numerous chest x-ray screenings largely was unexamined. The authors of this report examined the consistency of the MLP data with a modified 2-stage clonal expansion (TSCE) model of excess LC risk.

METHODS

By using a simulation model calibrated to the initial MLP data, the authors examined the expected statistical variance of LC incidence and mortality between the screening and control arms. A Bayesian estimation framework using a modified version of the TSCE model to evaluate the role of excess LC risk attributable to chest x-ray screening was derived and applied to the MLP data.

RESULTS

Simulation experiments indicated that the overall difference in LC deaths and incidence between the study arm and the control arm was unlikely (P = .0424 and P = .0104, respectively) assuming no excess risk of LC. The authors estimated that the 10-year excess LC risk for a man aged 60 years who smoked and who received 10 chest x-ray screenings was 0.574% (P = .0021).

CONCLUSIONS

The excess LC risk observed among screening arm participants was found to be statistically significant with respect to the TSCE model framework in part because of the incorporation of key risk correlates of age and screen frequency into the estimation framework.

Screening for early lung cancer. Results of the Memorial Sloan-Kettering study in New York

The Memorial Sloan-Kettering lung cancer screening program was begun in 1974 to evaluate sputum cytology as a supplement to the annual chest x-ray examination for early detection and diagnosis. The 10,040 adult, male cigarette smokers who enrolled were randomly assigned to receive annual chest x-ray examinations only or a dual screen with annual chest x-ray examination and four monthly sputum cytology evaluation. Over 40 percent of the 288 who developed lung cancer were diagnosed in stage I, and their survival was 76 percent at five years; overall survival was 35 percent. Nearly one third of the lung cancers detected on first examination on the dual screen, and 14 percent of those on subsequent examinations were found by cytologic examination. The same number of cancers developed in the x-ray screen only group, and were diagnosed at a later date. Despite the delay, survival and mortality were the same, suggesting that the squamous carcinomas detected by cytologic examination alone are very slow growing and tend to remain localized until detectable by x-ray examination.

Detection of true pathologic stage I lung cancer in a screening program and the effect on survival

One-hundred-sixty-nine lung cancers have occurred to date among 10,040 cigarette smoking men who participated in the New York Lung Cancer Detection Program. Almost 40% of the cases, 65, were still Stage I when their disease was diagnosed; 62 had thoracotomy and resection, and in 57, mediastinal node dissection confirmed that the mediastinum was free of metastases ("true pathologic" Stage I). Fifty-four of the 62 (87%) are still alive at this time, while only 15 of 104 (14%) of those with Stage II and III lung cancers are alive. Only two patients of the 62 in Stage I who were treated by resection died of lung cancer, both with T2 tumors. Two others are alive with metastases, one died postoperatively, and five died of other causes without evidence of lung cancer. The estimated probability of survival for true Stage I lung cancer is over 90% at five years, and close to 40% of all lung cancers can be detected in this favorable stage by present radiologic and cytologic screening techniques.