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Concept: Medical test

154

The anaplastic lymphoma kinase (ALK) gene rearrangement is a driver gene of non-small cell lung cancer (NSCLC). Positive expression of ALK gene rearrangement has been considered a molecular subtype of NSCLC, that there are special pathological characteristics and clinical prognosis. Furthermore, the tyrosine kinase inhibitor has demonstrated high effective in treating ALK positive NSCLC patients. Thus making molecular diagnostic testing for ALK expression is an important step in the process of pathological diagnosis. Currently, many detecting ALK expression assays are available or in development, clinical pathologists focus on how to choose the best method for routine diagnosis of lung cancer. There are many domestic and international authoritative guidelines recommend ALK detecting assays, technological process and relative standard. In the current review, we summarize the diagnostic tests available and the special sample types that could be used to identify patients with ALK-positive NSCLC.

Concepts: Gene expression, Cancer, Lung cancer, Non-small cell lung carcinoma, Pathology, Prognosis, Medical test, Anaplastic large cell lymphoma

145

Background Venous thromboembolism may be the earliest sign of cancer. Currently, there is a great diversity in practices regarding screening for occult cancer in a person who has an unprovoked venous thromboembolism. We sought to assess the efficacy of a screening strategy for occult cancer that included comprehensive computed tomography (CT) of the abdomen and pelvis in patients who had a first unprovoked venous thromboembolism. Methods We conducted a multicenter, open-label, randomized, controlled trial in Canada. Patients were randomly assigned to undergo limited occult-cancer screening (basic blood testing, chest radiography, and screening for breast, cervical, and prostate cancer) or limited occult-cancer screening in combination with CT. The primary outcome measure was confirmed cancer that was missed by the screening strategy and detected by the end of the 1-year follow-up period. Results Of the 854 patients who underwent randomization, 33 (3.9%) had a new diagnosis of occult cancer between randomization and the 1-year follow-up: 14 of the 431 patients (3.2%) in the limited-screening group and 19 of the 423 patients (4.5%) in the limited-screening-plus-CT group (P=0.28). In the primary outcome analysis, 4 occult cancers (29%) were missed by the limited screening strategy, whereas 5 (26%) were missed by the strategy of limited screening plus CT (P=1.0). There was no significant difference between the two study groups in the mean time to a cancer diagnosis (4.2 months in the limited-screening group and 4.0 months in the limited-screening-plus-CT group, P=0.88) or in cancer-related mortality (1.4% and 0.9%, P=0.75). Conclusions The prevalence of occult cancer was low among patients with a first unprovoked venous thromboembolism. Routine screening with CT of the abdomen and pelvis did not provide a clinically significant benefit. (Funded by the Heart and Stroke Foundation of Canada; SOME ClinicalTrials.gov number, NCT00773448 .).

Concepts: Cancer, Metastasis, Blood, Stroke, Prostate cancer, Screening, Randomness, Medical test

141

The diagnostic work-up for heparin induced thrombocytopenia (HIT) can take several days. Consequently patients may be speculatively switched onto replacement anticoagulant therapy before a diagnosis is confirmed. On-demand immunoassay diagnostic testing enables timely treatment decisions, based on test results.

Concepts: Medical terms, Diagnosis, Anticoagulant, Heparin, Thrombocytopenia, Immunoassay, Medical test, Heparin-induced thrombocytopenia

79

Major issues in the implementation of screening for lung cancer by means of low-dose computed tomography (CT) are the definition of a positive result and the management of lung nodules detected on the scans. We conducted a population-based prospective study to determine factors predicting the probability that lung nodules detected on the first screening low-dose CT scans are malignant or will be found to be malignant on follow-up.

Concepts: Cancer, Metastasis, Lung cancer, Cancer staging, Pneumonia, Tomographic reconstruction, Solitary pulmonary nodule, Medical test

39

The UK Lung Cancer Screening (UKLS) trial is a randomised pilot trial of low-dose CT (LDCT) screening for individuals at high risk of lung cancer. We assessed the long-term psychosocial impact on individuals participating in the UKLS trial.

Concepts: Epidemiology, Cancer, Metastasis, Lung cancer, Cancer staging, Randomized controlled trial, Tobacco smoking, Medical test

35

Dramatic increases have been seen over recent decades in the reported incidence of thyroid cancer, but owing to new modes of screening, hundreds of thousands of cases may be overdiagnoses - diagnosis of tumors that would not, if left alone, result in symptoms or death.

Concepts: Epidemiology, Cancer, Oncology, Medical terms, Prostate cancer, Screening, Overdiagnosis, Medical test

31

Lung cancer (LC) is the leading cause of cancer-related deaths worldwide. Early LC diagnosis is crucial to reduce the high case fatality rate of this disease. In this case-control study, we developed an accurate LC diagnosis test using retrospectively collected formalin-fixed paraffin-embedded (FFPE) human lung tissues and prospectively collected exhaled breath condensates (EBCs). Following international guidelines for diagnostic methods with clinical application, reproducible standard operating procedures (SOP) were established for every step comprising our LC diagnosis method. We analyzed the expression of distinct mRNAs expressed from GATA6 and NKX2-1, key regulators of lung development. The Em/Ad expression ratios of GATA6 and NKX2-1 detected in EBCs were combined using linear kernel support vector machines (SVM) into the LC score, which can be used for LC detection. LC score-based diagnosis achieved a high performance in an independent validation cohort. We propose our method as a non-invasive, accurate, and low-price option to complement the success of computed tomography imaging (CT) and chest X-ray (CXR) for LC diagnosis.

Concepts: Gene expression, Epidemiology, Cancer, Lung, Pneumonia, Medical imaging, Support vector machine, Medical test

29

Recurrence will develop in 30-50% of colorectal cancer (CRC) cases despite apparent clearance following treatment. Carcinoembryonic antigen (CEA) is the only guideline-recommended blood test for monitoring cases for recurrence, but its sensitivity and specificity are suboptimal. This observational study compared a novel 2-gene (methylated BCAT1 and IKZF1 DNA) blood test with CEA for detection of recurrent CRC. We conducted a paired comparison of the BCAT1/IKZF1 test with CEA (cut-off 5 ng/mL) in blood from patients in remission after treatment for primary CRC and undergoing surveillance. Blood collected in the 12 months prior to or 3 months after complete investigational assessment of recurrence status were assayed and the results compared by McNemar’s test. Of 397 patients enrolled, 220 underwent satisfactory assessment for recurrence and 122 had blood testing performed within the prescribed period. In 28 cases with recurrent CRC, CEA was positive in 9 (32%; 95% CI 16-52%) compared to 19 (68%; 95% CI 48-84%) positive for methylated BCAT1/IKZF1 (P = 0.002). All samples that were CEA positive were also BCAT1/IKZF1 positive. In 94 patients without clinically detectable recurrence, CEA was positive in 6 (6%, 95% CI 2-13%) and BCAT1/IKZF1 in 12 (13%, 95% CI 7-21%), P = 0.210. The odds ratio of a positive CEA test for recurrence was 6.9 (95% CI 2-22) compared to 14.4 (5-39) for BCAT1/IKZF1. The BCAT1/IKZF1 test was more sensitive for recurrence than CEA and the odds of recurrence given a positive test was twice that of CEA. The BCAT1/IKZF1 test should be further considered for monitoring cases for recurrence.

Concepts: Blood, Positive predictive value, Type I and type II errors, Sensitivity and specificity, Medical test

29

Lung cancer screening may detect cancer that will never become symptomatic (overdiagnosis), leading to overtreatment. Changes in size on sequential low-dose computed tomography (LDCT) screening, expressed as volume-doubling time (VDT), may help to distinguish aggressive cancer from cases that are unlikely to become symptomatic.

Concepts: Epidemiology, Cancer, Lung cancer, Cancer staging, Prostate cancer, Screening, Overdiagnosis, Medical test

28

Purpose To validate the recommendation of performing annual follow-up of nonsolid nodules (NSNs) identified by computed tomographic (CT) screening for lung cancer, all cases of lung cancer manifesting as NSN in the National Lung Screening Trial (NLST) were reviewed. Materials and Methods Institutional review board and informed consent were waived for this study. The NLST database was searched to identify all participants with at least one NSN on CT scan with lung cancer as the cause of death (COD) documented by the NLST endpoint verification process. Among the 26 722 participants, 2534 (9.4%) had one or more NSNs, and lung cancer as the COD occurred for 48 participants. On review, 21 of the 48 patients had no NSN in the cancerous lobe, which left 27 patients whose CT scans were reviewed by four radiologists: Group A (n = 12) were cases of lung cancer as the COD because of adenocarcinoma, and group B (n = 15) were cases of lung cancer as the COD because of other cell types. Frequency of lung cancer as the COD because of NSN and the time from randomization to diagnosis within these groups was determined. Results Six of the 12 patients in group A had no NSN in the cancerous lobe whereas the remaining six patients had a dominant solid or part-solid nodule in the lobe that rapidly grew in four patients, was multifocal in one patient, and had a growing NSN in one patient in whom diagnosis was delayed for over 3 years. Five of the 15 patients in group B had no NSN, and for the remaining 10 patients, lung cancer as the COD was not because of NSN. Conclusion It seems unlikely that patients with lung cancer as the COD occurred with solitary or dominant NSN as long as annual follow-up was performed. This lends further support that lung cancers that manifest as NSNs have an indolent course and can be managed with annual follow-up. (©) RSNA, 2016.

Concepts: Cancer, Metastasis, Lung cancer, Cancer staging, Tobacco smoking, Carcinoma, Solitary pulmonary nodule, Medical test