Trends in the Use of (18)F-Fluorodeoxyglucose PET Imaging in Surveillance of Non-Small-Cell Lung and Colorectal Cancer

Diagnostic performance of a deep-learning model using 18F-FDG PET/CT for evaluating recurrence after radiation therapy in patients with lung cancer

OBJECTIVE

We developed a deep learning model for distinguishing radiation therapy (RT)-related changes and tumour recurrence in patients with lung cancer who underwent RT, and evaluated its performance.

METHODS

We retrospectively recruited 308 patients with lung cancer with RT-related changes observed on 18F-fluorodeoxyglucose positron emission tomography-computed tomography (18F-FDG PET/CT) performed after RT. Patients were labelled as positive or negative for tumour recurrence through histologic diagnosis or clinical follow-up after 18F-FDG PET/CT. A two-dimensional (2D) slice-based convolutional neural network (CNN) model was created with a total of 3329 slices as input, and performance was evaluated with five independent test sets.

RESULTS

For the five independent test sets, the area under the curve (AUC) of the receiver operating characteristic curve, sensitivity, and specificity were in the range of 0.98-0.99, 95-98%, and 87-95%, respectively. The region determined by the model was confirmed as an actual recurred tumour through the explainable artificial intelligence (AI) using gradient-weighted class activation mapping (Grad-CAM).

CONCLUSION

The 2D slice-based CNN model using 18F-FDG PET imaging was able to distinguish well between RT-related changes and tumour recurrence in patients with lung cancer.

Compliance and initiative: A discussion on the relationship between standards and activities in radiopharmaceutical production

This study investigated how a standard could become reality-based in a workplace where certain types of deviations are not permitted, such as a radiopharmaceutical production unit. Compliance with standards is necessary to ensure the safety of individuals who manufacture such substances as well as the security of patients receiving treatment. In this qualitative case study, an ergonomic analysis of work (also known as activity analysis) was performed, with noncompliance recorded in internal audits as a starting point: the lack of double-checking in radiopharmaceutical synthesis cassette assembly. Field observations and self-confrontation interviews with workers from a production unit were conducted to analyze the activities. Although a double-check did not occur, the radiopharmaceutical synthesis operator apparently developed another risk control strategy, focusing his attention to the equipment assembly details, which necessitated continuous control and verification actions to ensure that there were no problems at this stage of production. A multilevel approach was used to demonstrate how the safety and quality of production processes based on standard compliance only become effective and adherent to the activity after resolving various conflicts at work, including control systems (external and internal audits), work collectives, the contradiction of the activity itself, and the discussion of singular situations arising daily. This study contributes to the discussion on workplace safety considering standardization and advances the discussion on changing perspectives regarding rule compliance.

Use of [18F]Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography after Curative Treatment of Non-Small-Cell Lung Cancer Patients: A Nationwide Cohort Study

[¹⁸F]Fluorodeoxyglucose positron emission tomography/computed tomography ([¹⁸F]FDG PET/CT) is a valuable imaging tool in the post-treatment management of non-small-cell lung cancer (NSCLC). This study aimed to investigate the trends in utilization and factors associated with the use of [¹⁸F]FDG PET/CT after curative-intent treatment. Data from 13,758 NSCLC patients diagnosed between 2007 and 2020 identified in the Danish Lung Cancer Registry, who underwent curative-intent treatment, were analyzed using multivariable regression. The results showed a significant increase in the use of [¹⁸F]FDG PET/CT scans, from 10.4 per 100 patients per year in 2007 to 39.6 in 2013, followed by a period of stability. Higher utilization rates were observed in patients who received radiotherapy (22% increase compared to surgical resection) and in patients with stage II-III disease (14% and 20% increase compared to stage I, respectively). Additionally, utilization was increased when other diagnostic procedures were performed, such as MRI, ultrasound, endoscopy, and biopsy. These findings highlight an increasing reliance on [¹⁸F]FDG PET/CT in post-treatment NSCLC, especially after radiotherapy and in patients with locally advanced disease, where treatment-induced radiographic changes and an increased risk of recurrence present a significant diagnostic challenge.

The usefulness of 18F-FDG PET/CT in follow-up and recurrence detection for patients with lung carcinoma and its impact on the survival outcome

Background

We assess the usefulness of 18F-FDG PET/CT for detection of recurrent or residual tumor in post treatment patients with NSCLC and comparing the results with CECT, and we evaluate its impact to the clinical assessment and overall survival of lung cancer patients.

Results

A prospective study of 63 patients with potentially resectable NSCLC, were divided into 2 groups according to the initial staging of the disease and the early response to treatment.

Group A (n=29) patients were treated by curative treatment, and group B (n=34) patients were treated by palliative treatment.

Evaluation of patients was done during the follow-up period clinically every 3 months and by 18F-FDG PET/CT and CECT imaging at 6 months intervals.

In group A, 18F-FDG PET/CT correctly diagnosed all recurrent or residual tumors (n=7) whereas CECT diagnosed only 5 with 2 false negative cases.

In group B, 18F-FDG PET/CT correctly diagnosed all recurrent or residual tumors (n=23) whereas CECT diagnosed 16 patients with 7 false negative cases.

By comparison of 18F-FDG PET/CT and CECT in detection of residual or recurrent lung cancer (n=30), the sensitivity, specificity, PPV, NPV, and accuracy of 18F-FDG PET/CT were 100%, 92%, 92%, 100%, and 96% respectively, while of CECT were 72%, 95%, 94%, 79%, and 84% respectively in correlation with reference standard data. The calculated SUV max ranged from 2.1 to 4.9.

There was a significant difference in overall survival between patients in routine scan who had positive 18F FDG PET/CT result (median survival 18 months) and those who had negative result (median survival 45 months) (P<0.0001).

Conclusion

18 F-FDG PET/CT plays an important role in distinguishing post treatment changes from tumor recurrence in patients with lung cancer. Follow-up or surveillance 18 F-FDG PET/CT is a prognostic indicator for overall survival of patients.

Treatment and Monitoring Variability in US Metastatic Breast Cancer Care

PURPOSE

Treatment and monitoring options for patients with metastatic breast cancer (MBC) are increasing, but little is known about variability in care. We sought to improve understanding of MBC care and its correlates by analyzing real-world claims data using a search engine with a novel query language to enable temporal electronic phenotyping.

METHODS

Using the Advanced Cohort Engine, we identified 6,180 women who met criteria for having estrogen receptor-positive, human epidermal growth factor receptor 2-negative MBC from IBM MarketScan US insurance claims (2007-2014). We characterized treatment, monitoring, and hospice usage, along with clinical and nonclinical factors affecting care.

RESULTS

We observed wide variability in treatment modality and monitoring across patients and geography. Most women received first-recorded therapy with endocrine (67%) versus chemotherapy, underwent more computed tomography (CT) (76%) than positron emission tomography-CT, and were monitored using tumor markers (58%). Nearly half (46%) met criteria for aggressive disease, which were associated with receiving chemotherapy first, monitoring primarily with CT, and more frequent imaging. Older age was associated with endocrine therapy first, less frequent imaging, and less use of tumor markers. After controlling for clinical factors, care strategies varied significantly by nonclinical factors (median regional income with first-recorded therapy and imaging type, geographic region with these and with imaging frequency and use of tumor markers; P < .0001).

CONCLUSION

Variability in US MBC care is explained by patient and disease factors and by nonclinical factors such as geographic region, suggesting that treatment decisions are influenced by local practice patterns and/or resources. A search engine designed to express complex electronic phenotypes from longitudinal patient records enables the identification of variability in patient care, helping to define disparities and areas for improvement.

PACIFIC: shifting tides in the treatment of locally advanced non-small cell lung cancer

The treatment paradigm of stage III, unresectable non-small cell lung cancer (NSCLC) has had few advancement since concurrent chemoradiotherapy was established as standard of care treatment. Despite modifications to radiotherapy, chemotherapy and surgical approaches, loco-regional and distant relapse remain high, which unfortunately has translated to poor survival outcomes. The PACIFIC study introduced immunotherapy to the domain of stage III NSCLC and has emerged as the fourth pillar in cancer treatment for these patients. The positive results of the study have excited both the radiation and medical oncology communities, demonstrating improvements in overall and progression-free survival (PFS). In this review, we discuss the details and impacts of the PACIFIC study, as well as the future implications for the treatment of stage III NSCLC.

Choosing wisely in oncology: necessity and obstacles

In the last decades, the survival of many patients with cancer improved thanks to modern diagnostic methods and progresses in therapy. Still for several tumours, especially when diagnosed at an advanced stage, the benefits of treatment in terms of increased survival or quality of life are at best modest when not marginal, and should be weighed against the potential discomfort caused by medical procedures. As in other specialties, in oncology as well the dialogue between doctor and patient should be encouraged about the potential overuse of diagnostic procedures or treatments. Several oncological societies produced recommendations similar to those proposed by other medical disciplines adhering to the Choosing Wisely (CW) campaign. In this review, we describe what was reported in the medical literature concerning adequacy of screening, diagnostic, treatment and follow-up procedures and the potential impact on them of the CW. We only marginally touch on the more complex topic of treatment appropriateness, for which several evaluation methods have been developed (including the European Society for Medical Oncology-magnitude of clinical benefit scale). Finally, we review the possible obstacles for the development of CW in the oncological setting and focus on the strategies which could allow CW to evolve in the cancer field, so as to enhance the therapeutic relationship between medical professionals and patients and promote more appropriate management.

The Value of FDG PET/CT in Treatment Response Assessment, Follow-Up, and Surveillance of Lung Cancer

OBJECTIVE

The purpose of this article is to summarize the evidence regarding the role of FDG PET/CT in treatment response assessment and surveillance of lung cancer and to provide suggested best practices.

CONCLUSION

FDG PET/CT is a valuable imaging tool for assessing treatment response for patients with lung cancer, though evidence for its comparative effectiveness with chest CT is still evolving. FDG PET/CT is most useful when there is clinical suspicion or other evidence for disease recurrence or metastases. The sequencing, cost analysis, and comparative effectiveness of FDG PET/CT and conventional imaging modalities in the follow-up setting need to be investigated.