Pit-fall sign on computed tomography predicts pleural involvement and poor prognosis in non-small cell lung cancer☆
Introduction
Non-small cell lung cancer (NSCLC) accounts for approximately 80–85% of primary lung cancer, which is the leading cause of cancer deaths in most industrialized countries [1]. Complete resection is the best modality for the cure, if applicable, but the postoperative prognosis remains unsatisfactory [2]. One of the most important factors to influence on the prognosis is the degree of pleural invasion by the tumor. If a tumor invades the chest wall beyond the visceral pleura, the primary tumor is classified into T3 and the 5-year survival rate after surgery is less than 40% even when no nodal metastasis or distant metastasis is documented [2]. If disseminated tumors are seen in the pleural cavity (T4), the 5-year survival rate is less than 10% [2], [3]. In addition, recent studies have revealed that visceral pleural invasion is also an important prognostic factor [4], [5]. Ichinose and co-workers documented a significant survival difference among patients having tumors not extending beyond the elastic layer of the visceral pleura (p0), tumors extending the elastic layer (p1), and tumors exposed to the surface of the visceral pleura (p2) [4]. Manac’h and co-workers also documented that the postoperative survival of patients having tumors with visceral pleural invasion (p1-2) was significantly worse than that of patients without visceral pleural invasion.
Although the degree of pleural invasion is clinically important, the accurate diagnosis is sometimes difficult preoperatively. Chest computed tomography (CT) and magnetic resonance imaging (MRI) are usually used in the evaluation of the tumor extent [6], and the diagnosis of chest wall invasion, pleural dissemination and pleural effusion can be easily made preoperatively [6], [7]. However, pleural dissemination and/or pleural effusion, which were not documented preoperatively, were sometimes revealed during operation. In addition, the accurate visceral pleural invasion cannot be made with preoperative CT and/or MRI. We have already identified a feature on chest CT (pit-fall sign) that suggests a possible pleural invasion by peripheral lung cancer [8]. Thus, in the present study, we prospectively examined the clinical significance of the pit-fall sign by assessing the diagnostic accuracy of pleural involvement and the prognostic significance in peripheral NSCLC.
Section snippets
Patients
A total of 103 consecutive NSCLC patients who underwent operation from 1 July 1994 through 31 June 1998 and met the following criteria were prospectively studied: (1) NSCLC presenting a peripheral solitary pulmonary nodule that was apparently located far from the pleural surface on CT; (2) no pleural effusion or disseminated tumors on CT; (3) no multiple nodules on CT; (4) no pneumonitis or atelectasis around the pulmonary nodule; (5) through pathological examination of pleural invasion
Pit-fall sign in NSCLC
Pit-fall sign was positive in 44 (46.7%) patients (Fig. 1a and Table 1). Pit-fall sign was more frequently seen in adenocarcinoma patients than squamous cell carcinoma patients. The incidence of positive pit-fall sign was significantly low in patients with poorly differentiated tumors. There was no significant correlation between the presence of pit-fall sign and p-stages (Table 1).
Pit-fall sign and pleural involvement
Although no apparent pleural involvement was documented on preoperative CT, malignant pleural effusion was
Discussion
In the present study, we first revealed the clinical significance of pit-fall sign on the preoperative CT. CT is the imaging method of choice in the diagnosis and the evaluation of tumor extent of primary lung cancer. Pleural indentation is a well-known imaging finding on CT that is characteristic of primary lung cancer, especially adenocarcinoma [11], [12]. However, the accurate evaluation of pleural involvement with CT is sometimes difficult. It has been reported that sensitivity and
References (18)
Revisions in the international system for lung cancer
Chest
(1997)- et al.
Prognostic factors obtained by a pathologic examination in completely resected non-small-cell lung cancer. An analysis in each pathologic stage
J Thorac Cardiovasc Surg
(1995) - et al.
Visceral pleural invasion by non-small cell lung cancer: an underrated bad prognostic factor
Ann Thorac Surg
(2001) - et al.
Diagnosis of visceral pleural invasion in resected lung cancer using jet stream of saline solution
Ann Thorac Surg
(1997) - et al.
Pleural signs of small pulmonary masses: pathologic correlation with chest radiograph and diagnostic value
Eur J Radiol
(1997) - et al.
Pleural cytologies in lung cancer withput pleural effusions
Ann Thorac Surg
(1997) - et al.
The Lung Cancer Surgical Study Sub-Group of the Japan Clinical Oncology Group
Lung Cancer
(2001) - et al.
Surgical therapy of early non-small cell lung cancer
Chest
(2000) - et al.
Surgery for non-small cell lung cancer: postoperative survival based on the revised tumor-node-metastasis classification and its time trend
Eur J Cardiothorac Surg
(2000)
Cited by (22)
Prognostic factors for overall survival of stage III non-small cell lung cancer patients on computed tomography: A systematic review and meta-analysis
2020, Radiotherapy and OncologyCitation Excerpt :The stage III cohort generally consisted of multiple histological types with a majority of squamous cell carcinoma and adenocarcinoma patients, except for 2 studies which consisted solely of adenocarcinoma [17] or squamous cell carcinoma [51] patients and 10 studies in which histological type was not reported specifically for stage III patients [14,31,33,35,39,74] or at all [20,50,64,70]. Stage III patients were treated exclusively with chemotherapy and/or radiotherapy in 39 studies [11–13,15,18,20,21,31,32,34–36,41,45,47,48,51,53–56,58–60,64,65,67,70–72,74,76,77,80–85], while surgery was an option in 25 publications [14,16,17,33,37–40,42–44,46,49,50,52,57,61–63,66,68,73,75,78,79]. A single study did not report treatment modalities [69].
Radiomics Signature: A Biomarker for the Preoperative Distant Metastatic Prediction of Stage I Nonsmall Cell Lung Cancer
2019, Academic RadiologyCitation Excerpt :Moreover, the Cox model showed pleural indentation was the independent predictor for the DM. Li et al found pit-fall sign on preoperative CT suggested a possible pleural involvement correlated with a poorer prognosis; the 5-year survival rate of pit-fall sign-positive patients was 46.5%, which was significantly lower than that of pit-fall sign-negative patients (68.9%; p = 0.044) (27). Lee found pleural indentation can differentiate the invasive adenocarcinoma from the noninvasive lesions (28).
Pleural contact decreases survival in clinical T1N0M0 lung cancer patients undergoing SBRT
2019, Radiotherapy and OncologyConcomitant Interstitial Lung Disease Is a Risk Factor for Pleural Invasion in Lung Cancer
2017, Annals of Thoracic SurgeryCitation Excerpt :They also suggested that patients with suspected VPI should be treated with lobectomy even if the tumor diameter is smaller than 2 cm. However, preoperative evaluation of VPI or M1a-Pl is not straightforward in ILD because the peripheral fibrotic lung of ILD obscures the VPI sign (the so-called pit fall sign) [11], and the small pleural nodule and minor effusion of M1a-Pl. Sato and colleagues [5] found that cancer recurrence was the main cause of death in lung cancer patients with ILD and was twice as high as death from respiratory failure, indicating that oncological control is important for survival.
Research Progress of Relationship between Pleural Deformation and Visceral Pleural Invasion in Lung Cancer Manifesting as Ground-glass Opacity
2022, Chinese Journal of Lung Cancer
- ☆
Part of this article appeared on the “Proceedings of ASCO 23:688, 2003(abstr. #2768)”.