Pure Ground-Glass Opacities: Potential for Surgical Cure in Adenocarcinoma; However Selection Is Key
Pure ground-glass opacities are a unique subset of pulmonary nodules that can represent benign findings, adenocarcinoma in situ/minimally invasive adenocarcinoma, or, in some cases, invasive adenocarcinoma. Although it is still unclear whether all adenocarcinoma in situ/minimally invasive adenocarcinoma appearing as pure ground-glass opacities will progress histologically to more invasive disease, it does appear that some proportion of pure ground-glass opacities have such potential. Timing of surgery for ground-glass opacities weighs the risks and benefits of surgical resection with those of close observation so as to avoid operating for benign disease but to operate early enough to avoid adenocarcinoma progression in lesions that are not benign. In their retrospective study of 308 patients with pure ground-glass opacities found to be lung adenocarcinoma presented in this issue of The Annals of Thoracic Surgery , Li and colleagues 1 have extended on their group’s prior findings 2 , 3 of excellent 5-year recurrence-free survival after resection for pure ground-glass opacities to now show a 100% recurrence-free survival 10 years after surgical resection. Of note 56.1% of their procedures were wedge resections, and 21.6% of all resections revealed invasive adenocarcinoma. Also on follow-up surveillance they found that just over 2% of these patients developed secondary primary lung cancers that were predominantly pure ground-glass opacities and primarily developed in the contralateral lung. Although these findings help clarify prognosis and the potential benefit of resection for ground-glass opacities, the study population and selection criteria for surgery must be clearly understood. First, only patients with pathologically proven adenocarcinoma were included. It is therefore unclear how many patients underwent resection for benign disease. Although presumably an acceptably low rate, this information would be helpful because the decision to operate must take into account the need to limit unnecessary operations. The authors do describe their selection process, which is to pursue surgery for either growth or persistence of ground-glass opacity on surveillance computed tomography. They also appropriately discuss the concern of prolonged observation because their 100% recurrence-free survival rate will not translate to patients whose pulmonary nodules develop solid components before surgery. The relatively small average pathologic tumor size of 1 cm likely suggests a fairly aggressive approach to resection as well as effective screening. Second, the definition for pure ground-glass opacities can vary, so the authors included a strict definition of only those with a consolidation/tumor ratio of zero. Third, although over half of the patients in the cohort underwent wedge resection, it is not clear how many of the wedge resections were for patients diagnosed with invasive adenocarcinoma. Fourth, as the authors note, this study cohort from China is largely made up of nonsmoking (87.0%) women (73.4%), so caution must be taken with extrapolation to other populations. Finally, the authors do not describe whether they routinely performed lymph node sampling and/or dissection during the index operation, which warrants follow-up studies. Despite some limitations, the authors should be commended for their work and commitment to demonstrating such promising long-term outcomes for patients with pure ground-glass opacities.
Li D, Deng C, Wang S, Li Y, Zhang Y, Chen H. Ten-Year Follow-up Results of Pure Ground-Glass Opacity-Featured Lung Adenocarcinomas After Surgery. Ann Thorac Surg. 2023 Aug;116(2):230-237. doi: 10.1016/j.athoracsur.2023.01.014. Epub 2023 Jan 13. PMID: 36646243.
Ten-Year Follow-up Results of Pure Ground-Glass Opacity-Featured Lung Adenocarcinomas After Surgery Di Li 1, Chaoqiang Deng 1, Shengping Wang 2, Yuan Li 3, Yang Zhang 1, Haiquan Chen 4 Affiliations expand PMID: 36646243 DOI: 10.1016/j.athoracsur.2023.01.014 Abstract Background: Previously, we have demonstrated that the 5-year recurrence-free survival after surgery of pure ground-glass opacity (GGO)-featured lung adenocarcinoma is 100%. This study aimed to reveal the long-term outcomes of these patients 10 years after surgery.
Methods: Lung adenocarcinoma patients who underwent surgery between December 2007 and December 2013 were reviewed. Patients with pure GGO-featured lung adenocarcinoma were enrolled. Postoperative survival and the risk of developing second primary lung cancer were analyzed.
Results: Overall, 308 cases of pure GGO-featured lung adenocarcinomas were included. Of these patients, 226 (73.4%) were female, 268 (87.0%) were nonsmokers, and 187 (60.7%) underwent sublobar resection. The median follow-up period after surgery was 112 months. The 10-year recurrence-free survival rate of these patients was 100%, and 10-year overall survival rate was 96.9%. Both 5-year and 10-year lung cancer-specific survival were 100%. There was no difference in 10-year recurrence-free survival rates between patients who underwent lobectomy or sublobar resection (P = .697). EGFR mutations were detected in 55.6% (84 of 151) of patients who underwent mutational analysis. The risk of developing secondary primary lung cancer for pure GGO-featured lung adenocarcinoma patients at 10 years after resection was 2.4%, and was not correlated with EGFR mutation status (P = .452).
Conclusions: No recurrence was observed in patients with pure GGO-featured lung adenocarcinomas 10 years after surgery, even when pathologically evaluated as invasive adenocarcinoma. Pure GGO can be cured by surgery. Surgery is recommended for the appropriate time window with the view to cure. Our study emphasizes that radiologic pure GGO-featured lung adenocarcinomas should be distinguished from other lung adenocarcinomas.
References - 1. Li D., Deng C., Wang S., Li Y., Zhang Y., Chen H.: Ten-year follow-up results of pure ground-glass opacity–featured lung adenocarcinomas after surgery. Ann Thorac Surg 2023; 116: pp. 230-238.
- 2. Fu F., Zhang Y., Wen Z., et. al.: Distinct prognostic factors in patients with stage I non–small cell lung cancer with radiologic part-solid or solid lesions. J Thorac Oncol 2019; 14: pp. 2133-2142.
- 3. Fu F., Zhang Y., Wang S., et. al.: Computed tomography density is not associated with pathological tumor invasion for pure ground-glass nodules. J Thorac Cardiovasc Surg 2021; 162: pp. 451-459.
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