Intraoperative pleural lavage cytology after lung resection as an independent prognostic factor for staging lung cancer

The International Association for the Study of Lung Cancer Lung Cancer Staging Project: Proposals for Revision of the Classification of Residual Tumor After Resection for the Forthcoming (Ninth) Edition of the TNM Classification of Lung Cancer

INTRODUCTION

The goal of surgical resection is to completely remove a cancer; it is useful to have a system to describe how well this was accomplished. This is captured by the residual tumor (R) classification, which is separate from the TNM classification that describes the anatomic extent of a cancer independent of treatment. The traditional R-classification designates as R0 a complete resection, as R1 a macroscopically complete resection but with microscopic tumor at the surgical margin, and as R2 a resection that leaves gross tumor behind. For lung cancer, an additional category encompasses situations in which the presence of residual tumor is uncertain.

METHODS

This paper represents a comprehensive review of evidence regarding these R categories and the descriptors thereof, focusing on studies published after the year 2000 and with adjustment for potential confounders.

RESULTS

Consistent discrimination between complete, uncertain, and incomplete resection is revealed with respect to overall survival. Evidence regarding specific descriptors is generally somewhat limited and only partially consistent; nevertheless, the data suggest retaining all descriptors but with clarifications to address ambiguities.

CONCLUSION

On the basis of this review, the R-classification for the ninth edition of stage classification of lung cancer is proposed to retain the same overall framework and descriptors, with more precise definitions of descriptors. These refinements should facilitate application and further research.

Intraoperative rapid diagnosis of pleural lavage cytology in non-small cell lung cancer

OBJECTIVE

Positive pleural lavage cytology (PLC +) is a poor prognostic factor for non-small cell lung cancer (NSCLC). However, data on the impact of intraoperative rapid diagnosis of PLC (rPLC) are lacking. Therefore, we evaluated the efficacy of rPLC before resection during surgery.

METHODS

A total of 1,838 patients who underwent rPLC for NSCLC between September 2002 and December 2014 were studied retrospectively. We assessed the clinicopathological factors between rPLC findings and the impact on survival of patients with curative resection.

RESULTS

The rPLC + status was observed in 96 (5.3%) among 1,838 patients. The rPLC + group had more unsuspected N2 (30%) than the rPLC- group (p < 0.001). The 5-year overall survival (OS) of patients who underwent lobectomy or more extensive resection with rPLC + , negative rPLC (rPLC-), and microscopic pleural dissemination (PD) and/or malignant pleural effusion (PE) were 67.3, 81.3, and 11.0%, respectively. In the rPLC + group, the prognosis of patients with pN2 was equal to that of pN0-1 (5-year OS: 77.9% vs. 63.4%, p = 0.263). Undetectable dissemination in the first evaluation immediately after starting surgery was found in 9% of rPLC + patients by additional evaluation of the thoracic cavity.

CONCLUSIONS

Patients with rPLC + have more favorable survival than those with microscopic PD/PE after surgery. Curative resection should be performed in patients with rPLC + , even if N2 is detected during surgery. However, the rPLC + group often has N2 upstaging; therefore, systematic nodal dissection should be performed in rPLC + patients for exact staging. rPLC may contribute to preventing oversight PD by re-evaluation during surgery.

Impact of Positive Pleural Lavage Cytology for Each Stage of Non-Small Cell Lung Cancer Patients

BACKGROUND

Positive preresection pleural lavage cytology (PLC⁺) is a poor prognostic factor in non-small cell lung cancer (NSCLC). This study evaluated the prognostic value of PLC⁺ for the different pathologic stages (p-stages) of NSCLC.

METHODS

A retrospective analysis was conducted of all 1293 staged patients who underwent curative resection in the Shizuoka Cancer Center Hospital, Shizuoka, Japan, for NSCLC to evaluate the impact of PLC⁺ on survival, specifically in patients with p-stage I NSCLC. The survival rate between patients with and without PLC⁺ was compared using the Kaplan-Meier method with the log-rank test for comparison.

RESULTS

PLC⁺ was identified in 50 of the 1293 patients (3.9%) and was correlated with lymph node metastasis (P < .001), a pathologic tumor size larger than 3 cm (P = .033), the presence of pleural invasion (P < .001), and adenocarcinoma (P = .038). In patients with PLC⁺, the 5-year disease-free survival (DFS) was 31.1%, compared with 75.7% for patients with a negative PLC (PLC^-) (P < .001). On multivariate analysis, the PLC⁺ status was an independent prognostic factor of DFS (hazard ratio 1.70; P = .013). Among the 818 patients with p-stage I NSCLC, PLC⁺ was identified in 22, with a 5-year DFS of 40.4%. The prognosis in patients with p-stage I NSCLC with PLC⁺ was equal to that in patients with p-stage IIIA NSCLC with PLC^- (5-year DFS, 40.4% and 39.0%).

CONCLUSIONS

PLC is an independent prognostic factor in early-stage NSCLC. Therefore, it may be appropriate to up-stage an NSCLC diagnosis in the presence of PLC⁺, especially for patients with p stage I.

Oncologic Outcomes of Surgery Versus SBRT for Non-Small-Cell Lung Carcinoma: A Systematic Review and Meta-analysis

BACKGROUND

The optimal treatment of stage I non-small-cell lung carcinoma is subject to debate. The aim of this study was to compare overall survival and oncologic outcomes of lobar resection (LR), sublobar resection (SR), and stereotactic body radiotherapy (SBRT).

METHODS

A systematic review and meta-analysis of oncologic outcomes of propensity matched comparative and noncomparative cohort studies was performed. Outcomes of interest were overall survival and disease-free survival. The inverse variance method and the random-effects method for meta-analysis were utilized to assess the pooled estimates.

RESULTS

A total of 100 studies with patients treated for clinical stage I non-small-cell lung carcinoma were included. Long-term overall and disease-free survival after LR was superior over SBRT in all comparisons, and for most comparisons, SR was superior to SBRT. Noncomparative studies showed superior long-term overall and disease-free survival for both LR and SR over SBRT. Although the papers were heterogeneous and of low quality, results remained essentially the same throughout a large number of stratifications and sensitivity analyses.

CONCLUSION

Results of this systematic review and meta-analysis showed that LR has superior outcomes compared to SBRT for cI non-small-cell lung carcinoma. New trials are underway evaluating long-term results of SBRT in potentially operable patients.

Comparison of the clinical benefits for non-small cell lung cancer patients between different volume of pleural lavage fluid following video-assisted thoracoscopic lobectomy and systematic mediastinal lymph node dissection: study protocol for a randomized controlled trial

Background

Pleural lavage is regularly performed before closing the chest wall in pulmonary surgeries to prevent pleural implantation of tumor cells and postoperative infection. However, scant data could be found in the literature regarding the optimal regimen for performing pleural lavage. To establish a proper volume of pleural lavage, we herein designed a protocol for a randomized controlled trial.

Methods

A total of 400 participants with non-small cell lung cancer undergoing video-assisted thoracoscopic surgery (VATS) lobectomy and systematic mediastinal lymph node dissection (MLND) will be randomly assigned to one of two groups: group A (500 mL pleural lavage fluid) and group B (3000 mL pleural lavage fluid). The primary outcomes include the levels of leukocytes, neutrophils, and inflammatory factors on the first postoperative day. The secondary outcomes include (i) the levels of leukocytes, neutrophils, and inflammatory factors on the second and third postoperative days; (ii) the incidence of postoperative fever on the first, second, and third postoperative days; (iii) the volumes of chest drainage within the first 3 operative days, the duration of drainage, and postoperative hospitalization; and (iv) the incidence of postoperative complications (incision infection, pain, atelectasis, hemorrhage, etc.) and the incidence of pleural effusion requiring thoracic puncture or drainage within 30 days after surgery. The main content of the analysis includes effectiveness and safety analysis. We will perform subgroup analyses to identify potential influence factors.

Discussion

As far as we know, this will be the first randomized controlled trial to compare the clinical outcomes between different volumes of pleural lavage fluid following VATS and MLND. Findings from this trial will determine the appropriate amount of pleural lavage before chest wall closure.

Trial registration

This study was registered with the Chinese Clinical Trial Registry ( on 17 March 2019. ChiCTR 1900021950).

Clinicopathological features of intraoperative pleural lavage cytology for non-small cell lung cancer

OBJECTIVE

The significance of clinicopathological features of pre- and post-resection pleural lavage cytology (PLC) for non-small cell lung carcinoma (NSCLC) currently remains unknown.

METHODS

Between January 2010 and December 2012, pre- and post-resection PLC were performed for NSCLC in 565 patients at Tohoku University, Miyagi Cancer Center, or Sendai Medical Center. The relationship between the clinicopathological features and patient outcomes was analyzed.

RESULTS

Twenty-two patients (3.9%) had positive findings from pre- or post-resection PLC. Both PLC were correlated with pT and pl factors, while only post-resection PLC was correlated with pN factor (p < 0.005). The 5-year disease-free survival (DFS) rate of the positive pre-resection PLC was significantly poorer than that of negative (26.7% vs. 76.9%, p < 0.0001). In addition, the 5-year DFS of the positive post-resection PLC was also poorer than that of negative (14.3% vs. 76.0%, p < 0.0001). Multivariate analyses revealed that both PLC were not independent prognostic factors in our study.

CONCLUSIONS

A significant association of post-resection PLC with N factor is considered to be characteristics of post-resection PLC different from pre-resection PLC. A prognostic impact of post-resection PLC and its detailed difference from pre-resection PLC should be clarified by further investigations.

[Latest Progress of Intraoperative Pleural Lavage Cytology in Lung Cancer Surgery]

非小细胞肺癌（non-small cell lung cancer, NSCLC）根治术中胸腔冲洗液细胞学检查是一种常用的检测肿瘤进展并评估患者预后的诊断技术。长期以来大量研究者致力于阐明术中胸腔冲洗液细胞学检查结果与肺癌患者术后生存及肿瘤复发转移的关系。由于不同研究间存在明显异质性，其结论也各有不同。但能肯定的是，胸腔冲洗液肿瘤细胞检查阳性已被证实为手术患者的不良预后因素之一。本文尝试从临床意义、影响因素及可能发生机制等角度就近年来术中胸膜腔冲洗的研究进展作一综述。

The role of surgical intervention in lung cancer with carcinomatous pleuritis

Patients with non-small cell lung cancer (NSCLC) associated with carcinomatous pleuritis are currently classified as having stage IV disease per the 7^th edition of the tumor-node-metastasis (TNM) system, which means that the disease is deemed incurable. In fact, the 5-year survival rate of these patients was only 2% in a large global cohort collected by the International Association for the Study of Lung Cancer. However, patients with carcinomatous pleuritis have heterogeneous conditions. Some have minimal pleural effusion, which is first detected at thoracotomy; some have numerous pleural nodules without any effusion; and others have massive effusion and nodules with symptoms. Several investigators have reported the contribution of surgical intervention to favorable outcomes of patients with carcinomatous pleuritis first detected at thoracotomy. These reports show a relatively higher 5-year survival rate of 15% to 37%. The extrapleural pneumonectomy (EPP) is a radical surgical procedure that is commonly employed in the treatment of malignant pleural mesothelioma. Two authors reported that they have successfully performed EPPs for the treatment of patients with carcinomatous pleuritis. Their 5-year survival rates were estimated to be 22% and 61%, a significantly improved outcome. Although the development of chemotherapeutic agents, including molecular targeted drugs, might have the potential to prolong the survival of patients with advanced lung cancer, surgical interventions including EPP might have a role in improving the survival of patients with carcinomatous pleuritis of minimal disease and those without massive effusion or numerous pleural nodules.

Prognostic Value of Pleural Lavage Cytology in Patients with Lung Cancer Resection: An Updated Meta-Analysis

OBJECTIVE

Pleural lavage cytology (PLC) is considered as a possible tool for assessing prognosis of lung cancer patients. We aimed to comprehensively review the prognosis value of PLC in patients undergoing surgical resection.

METHODS

We searched 4 electronic databases for relevant studies comparing positive PLC and negative PLC. The primary outcomes included survival rate and recurrence rate at maximum follow-up.

RESULTS

The meta-analysis included 28 studies, with a total of 20,714 patients. For the overall survival rate of all stages, the results demonstrated that positive pre-resection, post-resection and pooled PLC were associated with unfavorable survival: hazard ratio (HR) 2.89 (95% confidence interval [CI] 2.48-3.37), 2.70 (1.90-3.83), and 2.89 (2.52-3.31), respectively. For the stage I survival rate, the combined results also suggested that positive pre-resection, post-resection and pooled PLC were associated with unfavorable survival: HR 3.29 (95% CI 2.55-4.25), 4.85 (2.31-10.20), and 3.16 (2.53-3.94), respectively. Furthermore, a meta-analysis of 14 studies included 14,279 patients showed that positive pre-resection, post-resection and pooled PLC were associated with an increased risk of overall recurrence: risk ratio (RR) 2.45 (95% CI 1.91-3.15), 2.37 (1.11-5.09), and 2.37 (95% CI 2.00-2.80), respectively. Positive PLC was also associated with a high pleural recurrence (RR 4.77; 95% CI 3.13-7.26) or distant recurrence (RR 2.33; 95% CI 1.65-3.29).

CONCLUSIONS

Both positive pre- resection and post-resection PLC are associated with not only higher tumor recurrence but also unfavorable survival outcomes in patients with lung cancer resection. This technique can therefore act as a strong prognostic factor for tumor recurrence and adverse survival rates.

[The prognostic value of micrometastasis in non-small cell lung cancer]

肺癌是我国目前发病率和死亡率最高的恶性肿瘤。非小细胞肺癌（non-small cell lung cancer, NSCLC）占肺癌的80%-85%。诊断时的分期是NSCLC主要的预后因子，也是治疗模式选择的重要依据。然而，完全性切除术后的Ⅰ期的NSCLC仍有25%-30%的复发率。这部分复发的患者可能早期就存在局部和（或）远处的隐匿性转移。因此，很多研究开始对NSCLC患者进行微转移的检测，并评估其预后价值。本文总结了近年来的相关研究，并就NSCLC的淋巴结微转移、骨髓微转移、胸膜腔微转移及外周血微转移的预后作用进行综述。

Intrapleural chemotherapy improves the survival of non-small cell lung cancer patients with positive pleural lavage cytology

PURPOSE

Information regarding the treatment of pleural lavage cytology (PLC)-positive patients is still limited. This study evaluated the efficacy of intrapleural chemotherapy (IPC) in PLC-positive patients.

METHODS

Three hundred eighty-six of the 567 lung cancer patients who underwent surgery had undergone PLC after thoracotomy, following by a complete resection were evaluated. IPC was performed after surgery, and cisplatin or adriamycin was injected intrapleurally through the thoracic tube.

RESULTS

The pathological diagnosis showed that 17 patients (4.4 %) were positive for (or suspected to have) malignancy in their PLC. The univariate and multivariate analysis showed that only pleural invasion was a significant predictor of a PLC-positive status. The 5-year overall survival in PLC-positive patients was 38 % and that in PLC-negative patients was 84 %. Both the univariate (p < 0.01) and multivariate (p = 0.045) analyses showed that the status of PLC was significantly associated with the overall survival. Eight of the 17 PLC-positive patients underwent IPC. The 2-year OS rate in the patients treated with IPC was 88 % and that of those without IPC was 44 (p = 0.04).

CONCLUSION

IPC improved the postoperative survival in PLC-positive NSCLC patients, and a further prospective evaluation regarding this therapy is warranted.

Pleural lavage cytology immediately after thoracotomy in patients with completely resected non-small cell lung cancer

This study evaluated 325 patients who had undergone pleural lavage cytology (PLC) immediately after thoracotomy following a complete resection for non-small cell lung cancer (NSCLC) between 2004 and 2008. The number of patients with negative and positive findings in PLC was 309 and 13, respectively. The proportion of T1 in the PLC-positive group was significantly smaller than that of the PLC-negative group. The pathologic examinations revealed that the parietal pleural invasion was significantly more severe in the PLC-positive group than in the PLC-negative group. Pathologic lymphovascular invasion was also significantly more prominent in the PLC-positive group than in the PLC-negative group. The 5-year survival rate after surgery in the PLC-positive group and PLC-negative group was 54.7% and 79.0%, respectively. The positive finding in PLC showed a tendency of an unfavorable prognosis for NSCLC patents following complete resection. Further clinical studies will be necessary to evaluate the efficacy of adjuvant therapy for PLC-positive patients.

Advances in the diagnosis of pleural disease in lung cancer

Pleural disease in lung cancer can be benign or malignant with the latter carrying a grave prognosis. In this review, we describe and discuss the advances in pleural imaging, procedures, and biomarkers for the diagnosis of pleural diseases in lung cancer. Ultrasound and computed tomography are increasingly applied in the planning of pleural procedures to enhance diagnostic accuracy and safety whilst pleuroscopy gives excellent yield in excess of 93% in the evaluation of cytology negative pleural effusions. Invasion beyond the elastic layer of the visceral pleura upstages lung cancer, and may indicate a need for adjuvant chemotherapy. Biomarkers isolated from pleural fluid or tissue may aid in diagnosis and guide treatment in the future. Magnetic resonance imaging, positron emission tomography, narrow band imaging of the pleura and autofluorescence thoracoscopy are technologies that require further evaluation to better define their respective roles in the diagnostic algorithms of pleural diseases in lung cancer.