Distinct Clinicopathologic Characteristics and Prognosis Based on the Presence of Ground Glass Opacity Component in Clinical Stage IA Lung Adenocarcinoma

Abstract

Introduction: We evaluated differences in the clinicopathologic characteristics and prognosis based on the presence of ground glass opacity (GGO) components in small-sized lung adenocarcinoma. Methods:We retrospectively investigated 634 lung adenocarcinomas classed as c-stage IA in the eighth edition TNM classification. Staging was defined according to the solid component size measured by thin-section computed tomography. All tumors were grouped into either a GGO or solid group, based on the presence of a GGO component.Results: Of the cases, 215 (34%) were classed as c-stage IA1 (T1mi: 88, T1a-GGO: 102, T1a-solid: 25), 255 (40%) as c-stage IA2 (T1b-GGO: 122, T1b-solid: 133), and 164 (26%) as c-stage IA3 (T1c-GGO: 44, T1c-solid: 120). Among the 546 c-stage IA cases excluding the T1mi lesions, Cox regression analysis revealed that presence of GGO was an independently significant prognosticator (p ¼ 0.024). The result was validated in 494 c-stage IA lung adenocarcinomas with a nonpredominant GGO component, showing the presence of GGO as a significant prognosticator (p ¼ 0.048). When we evaluated the prognostic impact of GGO presence in each clinical stage, the 5-year overall survival (OS) was significantly different between the GGO and solid groups (IA1: 97.8% versus 86.6%, p ¼ 0.026; IA2: 89.3% versus 75.2%, p ¼ 0.007; IA3: 88.5% versus 62.3%, p ¼ 0.003). Furthermore, the 5-year overall survival b was distinct in parallel similar pathologic findings when comparing a lepidic versus an invasive component (IA1: 97.9% versus 85.6%, p ¼ 0.031; IA2: 86.1% versus 69.4%, p ¼ 0.007; IA3: 77.5% versus 55.8%, p < 0.001).Conclusions: Clinicopathologic and oncologic outcomes were disparate based on the presence of a GGO component in the eighth edition TNM classification of c-stage IA lung adenocarcinoma.

Validation of the Eighth Edition Clinical T Categorization System for Clinical Stage IA, Resected Lung Adenocarcinomas: Prognostic Implications of the Ground-Glass Opacity Component

“…19 A different approach, the mixture cure model, was thus employed in this study to investigate the long-term prognostic potential of nodule type. Our study results, which partly coincide with those of past studies, 6,7 reported that the nodule type (i.e., PSN) could be used as a long-term prognostic indicator for surgical candidates with clinical stage IA adenocarcinomas. One may argue that the solid portion size would be different between PSNs and solid nodules even in the same cT category and that such discrepancy would be the potential confounder.…”

“…Recently, a few studies reported the distinct prognosis of PSNs compared with that of solid nodules. [5][6][7] Aokage et al 5 compared the overall survival (OS) of patients with clinical stage I, resected adenocarcinomas characterized by PSNs and solid nodules and revealed that those with PSNs had a more favorable prognosis in clinical stages IA2 and IA3. In addition, Ye et al 6 reported the excellent prognosis of patients with resected adenocarcinomas that appeared as PSNs in clinical stage IA and reported that neither the solid portion size nor the total tumor size could predict the prognosis of PSNs.…”

“…For instance, cT category has not been used as an independent variable. [5][6][7] In this study, we therefore aimed to validate the prognostic value of cT category in clinical stage IA, resected lung adenocarcinomas using a multivariable analysis that included nodule type, cT category, and their interaction term. Moreover, we aimed to evaluate the independent prognostic role of nodule type (i.e., the presence of GGO) using long-term follow-up data with two distinct survival analysis methods: the Cox proportional hazard model and the mixture cure model.…”

Invasiveness and surgical timing evaluation by clinical features of ground‐glass opacity nodules in lung cancers

“…It has been reported that five‐year‐survival in patients with AIS and MIA presenting with GGO nodules on chest CT could be 100% following surgical resection . However, in another study, the five‐year survival rates in stage IA1, IA2, and IA3 which presented in GGO nodules were 97.8%, 89.3%, and 88.5%, respectively . Hence, the surgical timing for the GGO nodules should be considered at the MIA stage.…”

“…5 However, in another study, the five-year survival rates in stage IA1, IA2, and IA3 which presented in GGO nodules were 97.8%, 89.3%, and 88.5%, respectively. 12,13 Hence, the surgical timing for the GGO nodules should be considered at the MIA stage. Previous reports have revealed that pure GGO nodules could be diagnosed as IA ultimately after surgical resection 14,15 and IA could also be misdiagnosed as a clinically noninvasive tumor on a preoperative CT scan just according to the CT features.…”