Study examines outcomes of resection for ground-glass adenocarcinomas in the lungs
A study from researchers at Harvard Medical School looked into clinical outcomes for resected lung adenocarcinomas, manifesting as subsolid nodules during CT scans, to identify the most effective patient care strategy. The results are published in the American Journal of Roentgenology. [1]
The retrospective study examined medical records from 469 patients over an eight-year period, all of whom underwent resection between January 2012 and December 2020. Researchers compared outcomes from three types of nodules found on CT images from the patients: pure ground-glass nodules (pGGNs), heterogeneous ground-glass nodules (GGNs) and part-solid nodules (PSNs).
“These nodules present a potential clinical conundrum, having indolent behavior but a high-risk of malignancy,” the authors, led by Jingshuo D. Sun, MD, of Brigham Women’s Hospital and Harvard Medical School, wrote. “Approximately one quarter of subsolid nodules are transient inflammatory processes; however, those nodules that persist on follow-up imaging overwhelmingly represent a diagnosis along a spectrum related to adenocarcinoma: atypical adenomatous hyperplasia, adenocarcinoma in situ, minimally invasive adenocarcinoma, and invasive adenocarcinoma.”
CT examinations from the study cohort were independently reviewed by two board-certified thoracic radiologists, each blinded to pathological and clinical outcomes of the patients. However, the location of the nodules was preidentified. The radiologists classified each nodule as pGGN, GGN or PSN based on their expertise. The researchers then compared the radiologists’ findings to patient outcomes.
Results showed that patients with pGGNs demonstrated exceptional clinical outcomes. These nodules, characterized by increased but not definitively solid density, exhibited notably lower frequencies of invasive adenocarcinoma and negligible five-year recurrence rates. Conversely, GGNs and PSNs exhibited higher rates of invasive adenocarcinoma and recurrence, suggesting a closer resemblance in outcomes between the two nodule types.
When the researchers looked into details on how the patients were treated, they made a variety of discoveries. First, clinical outcomes point to a need for surveillance rather than immediate resection for truly homogeneous pGGNs, given their excellent clinical outcomes. However, for GGNs resection should be a primary consideration, especially if the nodule is displaying an increasing internal density—and this was true even if the nodules were not fully solid. The same care strategy also produced the best outcomes for patients with PSNs.
“Further evidence showing distinct clinical outcomes in patients with heterogeneous GGNs would support tailoring management guidelines for this increasingly recognized subset of subsolid nodules,” the authors said, adding that accurate classification of subsolid nodules, based on radiographic features, is crucial for determining appropriate treatment strategies and optimizing patient outcomes.
The full study is available at the link below.