Imaging Follow-Up of Nonsurgical Therapies for Lung Cancer: AJR Expert Panel Narrative Review

Novel PET-CT-MR Imaging Based Quantitative Technique for Accurate Assessment of Radiation Induced Injuries

Radiation-induced injuries (RIIs) are significant complications of radiation therapy used in cancer treatments and affect organs in a systemic fashion such as the heart, lungs, liver, and bone marrow. Such ionizing radiation leads to inflammation, fibrosis, and/or irreparable DNA damage, each of which can significantly impact patient's quality of life, underscoring the need for advanced diagnostic and imaging techniques. A novel combination of PET/Computed Tomography (CT) with Quantitative MR Imaging has emerged as a crucial tool for early diagnosis and timely evaluation of RIIs. This review focuses on the important role of quantitative PET-CT-MR imaging in diagnosing and monitoring RIIs.

Lung Needle Biopsy and Lung Ablation: Indications, Patient Management, and Postprocedure Imaging Findings

The clinical role and use of percutaneous transthoracic needle biopsy (TTNB) and ablation of lung tumors are evolving. Here we discuss important considerations for referring providers, including current and emerging indications supported by guidelines, critical aspects of pre and postprocedure patient management, and expected postprocedure imaging findings.

Ablation of Stage I-II Non-Small Cell Lung Cancer in Patients With Interstitial Lung Disease: A Multicenter Retrospective Study

BACKGROUND. Treatment options for patients with interstitial lung disease (ILD) who develop stage I-II non-small cell lung cancer (NSCLC) are severely limited, given that surgical resection, radiation, and systemic therapy are associated with significant morbidity and mortality. OBJECTIVE. The aim of this study was to evaluate the safety and efficacy of percutaneous ablation of stage I-II NSCLC in patients with ILD. METHODS. This retrospective study included patients with ILD and stage I-II NSCLC treated with percutaneous ablation in three health systems between October 2004 and February 2023. At each site, a single thoracic radiologist, blinded to clinical outcomes, reviewed preprocedural chest CT examinations for the presence and type of ILD according to 2018 criteria proposed by the American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Latin American Thoracic Society. The primary outcome was 90-day major (grade ≥ 3) adverse events, based on Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. Secondary outcomes were hospital length of stay (HLOS), local tumor control, and overall survival (OS). RESULTS. The study included 33 patients (19 men, 14 women; median age, 78 years; 16 patients with Eastern Cooperative Oncology Group performance status ≤ 1) with ILD who underwent 42 percutaneous ablation sessions (21 cryoablations, 11 radiofrequency ablations, 10 microwave ablations) of 43 NSCLC tumors ((median tumor size, 1.6 cm; IQR, 1.4-2.5 cm; range, 0.7-5.4 cm; 37 stage I, six stage II). The extent of lung fibrosis was 20% or less in 24 patients; 17 patients had imaging findings of definite or probable usual interstitial pneumonia. The 90-day major adverse event rate was 14% (6/42), including one CTCAE grade 4 event. No acute ILD exacerbation or death occurred within 90 days after ablation. The median HLOS was 1 day (IQR, 0-2 days). Median imaging follow-up for local tumor control was 17 months (IQR, 11-32 months). Median imaging or clinical follow-up for OS was 16 months (IQR, 6-26 months). Local tumor control and OS were 78% and 77%, respectively, at 1 year and 73% and 46% at 2 years. CONCLUSION. Percutaneous ablation appears to be a safe and effective treatment option for stage I-II NSCLC in the setting of ILD after multidisciplinary selection. CLINICAL IMPACT. Patients with ILD and stage I-II NSCLC should be considered for percutaneous ablation given that they are frequently ineligible for surgical resection, radiation, and systemic therapy.

Spectrum of Imaging Patterns of Lung Cancer following Radiation Therapy

Radiation therapy using conventional or newer high-precision dose techniques, including three-dimensional conformal radiotherapy, intensity-modulated radiation therapy, stereotactic body radiation therapy, four-dimensional conformational radiotherapy, and proton therapy, is an important component of treating patients with lung cancer. Knowledge of the radiation technique used and the expected temporal evolution of radiation-induced lung injury, as well as patient-specific parameters such as previous radiotherapy, concurrent chemoradiotherapy, or immunotherapy, is important in image interpretation. This review discusses factors that affect the development and severity of radiation-induced lung injury and its radiological manifestations, as well as the differences between conventional and high-precision dose radiotherapy techniques.

Outcomes following cryoablation of stage IA non-small cell lung cancer in patients with and without interstitial lung disease: A retrospective single-center cohort study

OBJECTIVE

To compare the safety and efficacy of cryoablation of treatment-naïve stage IA non-small cell lung cancer (NSCLC) in patients with and without interstitial lung disease (ILD).

MATERIALS AND METHODS

This retrospective single-center cohort study evaluated 33 consecutive patients (24 females, median age 75 years, Eastern Cooperative Oncology Group performance score 0-3) with ILD (9 patients) and without ILD (24 patients) who underwent 39 percutaneous cryoablations to treat 42 stage IA (8th IASLC edition) NSCLC measuring 1.2 cm (range 0.5-2.6 cm) from 2018 to 2022. Presence of ILD was determined according to 2018 American Thoracic Society Criteria on pre-ablation CT scans. The primary outcome was 90-day adverse events graded by the Common Terminology Criteria for Adverse Events (CTCAE) v5.0. Secondary outcomes were hospital length of stay (LOS), local recurrence-free survival, overall survival, and the cumulative incidence of local recurrence with death as a competing risk.

RESULTS

Adverse events ranged from grade 1-3 and occurred more often in the non-ILD group (p <.001). No acute exacerbation of ILD or death occurred within 90 days after cryoablation. The median LOS was 1 day (interquartile range 1-2 days) and did not differ between groups. One patient with ILD and two patients without ILD died after 22, 26, and 27 months from causes unrelated to cryoablation. Median imaging follow-up was 11 months (range, 0-47 months) and three tumors (7%) showed local recurrence after 4, 17, and 22 months. No difference in the cumulative incidence of local recurrence (p =.56) was found. Among all patients, local recurrence-free survival on a per-tumor basis and overall survival were 97% and 100% at 1 year, respectively.

CONCLUSION

Adverse events and local recurrence following percutaneous cryoablation of stage IA NSCLC did not differ between patients with and without ILD. No acute exacerbation of ILD or death within 90 days were observed.