Prediction of Pleural Lavage Cytology According to Thin-Section Computed Tomography in Non-Small-Cell Lung Cancer

BACKGROUND

Although the positive rate of preresection pleural lavage cytology (PLC) is low, it is an important indicator of poor prognosis for non-small-cell lung cancer patients with frequent pleural dissemination (PD) recurrence. Thin-section computed tomography (TSCT) can reveal relationships between a primary tumor and the pleura at 1 to 2 mm intervals, and this is associated with visceral pleural invasion (VPI). However, its association with PLC remains unclear. Therefore, we aimed to improve PLC efficiency and predict PD recurrence by understanding the relationship between PLC and preoperative TSCT findings.

PATIENTS AND METHODS

Between January 2014 and December 2018, we reviewed 978 patients with non-small-cell lung cancer who underwent PLC tests during complete resection surgery. Preoperative TSCT findings were evaluated, and factors with the highest specificity (proportion of patients with radiologically to pathologically diagnosed positive PLC) were investigated. We also evaluated their relationships with VPI and PD recurrence.

RESULTS

PLC positive was identified in 55 (5.6%) of the 978 patients. The two TSCT findings predicting PLC results, "the absence of pleural findings," ie, tumor not attached to pleura or without pleural tag, and "consolidation-to-tumor ratio ≤0.5", had a specificity of 100% (95% confidence interval: 90.4%-100%); additionally, all cases with these findings were VPI negative and had no PD recurrence. And 24% of the cohort had either of these findings.

CONCLUSION

The absence of pleural findings and/or consolidation-to-tumor ratio ≤0.5 of primary tumor on preoperative TSCT can predict PLC negativity with very high probability; therefore, PLC can be omitted for such patients.

Reappraising the clinical usability of consolidation-to-tumor ratio on CT in clinical stage IA lung cancer

Objectives

Ground-glass opacity (GGO) on computed tomography is associated with prognosis in early-stage non-small cell lung cancer (NSCLC) patients. However, the stratification of the prognostic value of GGO is controversial. We aimed to evaluate clinicopathologic characteristics of early-stage NSCLC based on the consolidation-to-tumor ratio (CTR), conduct multi-pronged analysis, and stratify prognosis accordingly.

Methods

We retrospectively investigated 944 patients with clinical stage IA NSCLC, who underwent curative-intent lung resection between August 2018 and January 2020. The CTR was measured and used to categorize patients into six groups (1, 0%; 2, 0–25%; 3, 25–50%; 4, 50–75%; 5, 75–100%; and 6, 100%).

Results

Pathologic nodal upstaging was found in 1.8% (group 4), 9.0% (group 5), and 17.4% (group 6), respectively. The proportion of patients with a high grade of tumor-infiltrating lymphocytes tended to decrease as the CTR increased. In a subtype analysis of patients with adenocarcinoma, all of the patients with predominant micro-papillary patterns were in the CTR > 50% groups, and most of the patients with predominant solid patterns were in group 6 (47/50, 94%). The multivariate analysis demonstrated that CTR 75–100% (hazard ratio [HR], 3.85; 95% confidence interval [CI], 1.58–9.36) and CTR 100% (HR, 5.58; 95% CI, 2.45–12.72) were independent prognostic factors for DFS, regardless of tumor size.

Conclusion

We demonstrated that the CTR could provide various noninvasive clinicopathological information. A CTR of more than 75% is the factor associated with a poor prognosis and should be considered when making therapeutic plans for patients with early-stage NSCLC.

Pathological features and prognostic implications of ground-glass opacity components on computed tomography for clinical stage I lung adenocarcinoma

PURPOSE

To investigate the prognostic implications and pathological features of clinical stage I lung adenocarcinoma with ground-glass opacity (GGO) on computed tomography (CT).

METHODS

The subjects of this retrospective study were 1228 patients with lung adenocarcinoma classified as clinical stage I, who underwent complete resection by lobectomy. The patients were divided into four groups based on the presence and proportion of GGO according to the consolidation-to-tumor ratio (CTR); A, CTR ≤ 0.5; B, 0.5 < CTR ≤ 0.75; C, 0.75 < CTR ≤ 1.0 with GGO; D, without GGO (pure-solid). We compared overall survival, pathological findings (N/ly/v/STAS), and histological subtypes within each clinical stage among the four groups.

RESULTS

We found no significant differences among tumors with GGO (groups A, B and C) for prognosis or pathological findings in all the clinical stages. The prognoses of groups A, B and C were significantly better than that of group D for patients with clinical stages IA2-IB disease. Tumors without GGO on CT had a significantly larger number of positive N, ly, v and STAS in almost all stages than tumors with GGO on CT. Tumors without GGO on CT had significantly more solid predominant and less lepidic predominant adenocarcinoma.

CONCLUSION

Not the proportion of GGO, but its presence on CT, as well as the size of the solid component, were correlated significantly with pathological characteristics and survival.

Radiologic Criteria in Predicting Pathologic Less Invasive Lung Cancer According to TNM 8th Edition

PURPOSE

The Japan Clinical Oncology Group Study 0201 has proposed radiologic criteria on thin-slice computed tomography to diagnose pathologic less invasive lung adenocarcinoma that could be a candidate for sublobar resection based on the previous tumor, node, metastasis classification system (TNM). The aim of this study was to propose the new radiologic criteria for predicting pathologic less invasive cancer according to the 8th edition TNM.

PATIENTS AND METHODS

We analyzed 744 patients who had peripheral clinical Tis-T1cN0M0 non-small-cell lung cancer of 3 cm or less and underwent complete resection by lobectomy from 2003 to 2011. We defined lung cancer with no nodal involvement and no vessel invasion pathologically as a pathologic less invasive cancer and investigated the radiologic criteria on the basis of the solid component size and by the consolidation-to-tumor (C/T) ratio (calculated with the maximum solid component diameter divided by the maximum tumor diameter) by using preoperative thin-slice computed tomography to predict them with a specificity of 97% or more, and evaluated overall survival.

RESULTS

Patients with clinical Tis/T1mi/T1a disease had no pathologic invasive cancer except for one patient (specificity, 99%). From the investigation with the C/T ratio, only the criterion of C/T ratio 0.5 or less met the standard (specificity, 100%). The final specificity after combining these criteria was 99.6%, and they showed excellent prognosis (5-year overall survival rate, 96.2%).

CONCLUSION

Lung cancer with clinical Tis/T1mi/T1a or a C/T ratio of 0.5 or less can be completely cured by sublobar resection with sufficient margin because of its less invasive nature pathologically.