Prevalence of benign pulmonary lesions excised for suspicion of malignancy: could it reflect a quality management index of indeterminate lung lesions?

Surgical Resection of Benign Nodules in Lung Cancer Screening: Incidence and Features

Introduction

Interventions and surgical procedures are common for nonmalignant lung lesions detected on lung cancer screening (LCS). Inadvertent surgical resection of benign nodules with a clinical suspicion of lung cancer can occur, can be associated with complications, and adds to the cost of screening. The objective of this study is to assess the characteristics of surgically resected benign nodules detected on LCS computed tomography which were presumed to be lung cancers.

Methods

This retrospective study included 4798 patients who underwent LCS between June 2014 and January 2021. The benign lung nodules, surgically resected with a presumed cancer diagnosis, were identified from the LCS registry. Patient demographics, imaging characteristics, and pathologic diagnoses of benign nodules were analyzed.

Results

Of the 4798 patients who underwent LCS, 148 (3.1%) underwent surgical resection of a lung nodule, and of those who had a resection, 19 of 148 (12.8%) had a benign diagnosis (median age = 64 y, range: 56-77 y; F = 12 of 19, 63.2%; M = seven of 19, 36.8%). The median nodule size was 10 mm (range: 6-31 mm). Most nodules were solid (15 of 19, 78.9%), located in the upper lobes (11 of 19; 57.9%), and were peripheral (17 of 19, 89.5%). Most nodules (13 of 17; 76.5%) had interval growth, and four of 17 (23.5%) had increased fluorodeoxyglucose uptake. Of the 19 patients, 17 (89.5%) underwent sublobar resection (16 wedge resection and one segmentectomy), whereas two central nodules (10.5%) had lobectomies. Pathologies identified included focal areas of fibrosis or scarring (n = 8), necrotizing granulomatous inflammation (n = 3), other nonspecific inflammatory focus (n = 3), benign tumors (n = 3), reactive lymphoid hyperplasia (n = 1), and organizing pneumonia (n = 1).

Conclusions

Surgical resections of benign nodules that were presumed malignant are infrequent and may be unavoidable given overlapping imaging features of benign and malignant nodules. Knowledge of benign pathologies that can mimic malignancy may help reduce the incidence of unnecessary surgeries.

The Prevalence of Benign Pathology Following Major Pulmonary Resection for Suspected Malignancy

BACKGROUND

In the era of lung cancer screening with low-dose computed tomography, there is concern that high false-positive rates may lead to an increase in nontherapeutic lung resection. The aim of this study is to determine the current rate of major pulmonary resection for ultimately benign pathology.

MATERIALS AND METHODS

A single-institution, retrospective analysis of all patients > 18 y who underwent major pulmonary resection between 2013 and 2018 for suspected malignancy and had benign final pathology was performed.

RESULTS

Of 394 major pulmonary resections performed for known or presumed malignancy, 10 (2.5%) were benign. Of these 10, the mean age was 61.1 y (SD 14.6). Most were current or former smokers (60%). Ninety percent underwent a fluorodeoxyglucose positron emission tomography scan. Median nodule size was 27 mm (IQR 21-35) and most were in the right middle lobe (50%). Preoperative biopsy was performed in four (40%) but were nondiagnostic. Video-assisted thoracoscopic lobectomy (70%) was the most common surgical approach. Final pathology revealed three (30%) infectious, three (30%) inflammatory, two (20%) fibrotic, and two (20%) benign neoplastic nodules. Two (20%) patients had perioperative complications, both of which were prolonged air leaks, one (10%) patient was readmitted within 30 d, and there was no mortality.

CONCLUSIONS

A small percentage of patients (2.5% in our series) may undergo major pulmonary resection for unexpectedly benign pathology. Knowledge of this rate is useful to inform shared decision-making models between surgeons and patients and evaluation of thoracic surgery program performance.

Lung Resection Without Tissue Diagnosis: A Pragmatic Perspective on the Indeterminate Pulmonary Nodule

BACKGROUND

The indeterminate pulmonary nodule is a common clinical problem. Preoperative tissue diagnosis is not always possible, despite all attempts. The objectives of this study were to determine the frequency of a malignant diagnosis in this scenario and whether attempted preoperative biopsy impacted estimation of the risk of malignancy.

PATIENTS AND METHODS

We reviewed 500 consecutive cases of pulmonary resection without a preoperative tissue diagnosis at a tertiary care center from 2009 to 2013. Age, sex, smoking status, prior malignancy, tumor size, and whether or not tissue diagnosis had been attempted were recorded. Logistic regression models were constructed to determine factors associated with a malignant diagnosis.

RESULTS

There were 297 males (59.4%), the mean age was 64.9 years, and 412 had a smoking history (82.4%). Also, 203 patients (40.6%) had a malignancy history, and 36 patients (7.2%) had previous lung cancer. Biopsy was attempted for 102 patients (20.5%). The final diagnosis was lung cancer in 336 patients (67.2%), metastatic cancer in 93 patients (18.6%), and benign tumour in 71 patients (14.2%). Male sex, increasing age, smoking history, and prior lung cancer were positive predictors of lung cancer. Model discrimination was good (c-statistic, 0.83). Attempted biopsy did not alter model discrimination.

CONCLUSION

In this cohort, 86% of resected lesions were malignant. The decision to pursue preoperative tissue diagnosis did not change the predictive ability offered by clinical factors. These findings are reassuring in the scenario when a patient is operable but the diagnosis remains unknown.

Evaluation of DWI and ADC Sequences' Diagnostic Values in Benign and Malignant Pulmonary Lesions

OBJECTIVE

The gold standard for the diagnosis of lung cancer is conducting a histopathologic study. It is also diagnosed based on some features of a computed tomography (CT) scan. Imposed radiation is a prominent side effect of a CT scan. Diffusion-weighted imaging (DWI) apparent diffusion coefficient (ADC) images have currently been used in the diagnosis of different lesions, including those of the brain and breast, and their uses in lung lesions are being evaluated. In this study, to find a safe, sensitive, and specific method, we aimed to assess DWI imaging to replace the CT scan and the positron emission tomography scan.

MATERIAL AND METHODS

A total of 29 patients were enrolled in the study. In b800 images in DWI, spinal cord and lesion signals were measured, and the lesion-to-cord-signal ratio (LCR) was calculated. The ADC value was measured in a quantitative way. Lesions were also graded qualitatively in b800 DWI sequences.

RESULTS

There was a significant difference between malignant and benign lesions in terms of DWI grading in b800 images (p<0.001). There was a significant difference between ADC means of a malignant and benign lesion (p=0.003). The mean LCR for malignant lung lesions was significantly higher than that of the benign ones (p<0.001). Considering Grade 3 as the cutoff in DWI grading results in sensitivity, specificity, and accuracy of 89%, 90%, and 89.6%, respectively. For ADC values, sensitivity, specificity, and accuracy of 79%, 80%, and 79.3%, respectively, were obtained when the cutoff was 1.027×10^-3 sec/mm². The sensitivity of 84%, the specificity of 90%, and the accuracy of 86.2% were calculated for the LCR in a cutoff of 0.983. In this study, all three parameters had an area under the curve of ≥0.8, meaning that these variables were valuable for the differentiation of benign and malignant lesions.

CONCLUSION

Diffusion-weighted magnetic resonance imaging is a noninvasive tool, with no contrast agent and requiring ionizing radiations, which could be used for the qualitative, quantitative, and semiquantitative assessment of pulmonary lesions.

[Clinical-radiological-pathological Characteristics of 297 Cases of Surgical Pathology Confirmed Benign Pulmonary Lesions in Which Malignancy Could Not Be Excluded in Preoperative Assessment: A Retrospective Cohort Analysis in a Single Chinese Hospital]

背景与目的

随着癌症早筛意识的提高，低剂量计算机断层扫描(low-dose computed tomography, LDCT)用于肺癌筛查在中国广泛开展。尽管有部分胸部LDCT筛查所见的肺部病灶是肿瘤病灶，但大多数的肺部结节是良性病变。如何有效的对肺部病灶进行术前鉴别，如何降低部分可避免手术的良性疾病的手术切除比例，是需要关注的问题。

方法

本研究纳入2017年1月1日-2018年12月31日期间北京协和医院诊治的，术前考虑肺部恶性病变不能除外，经手术病理确认为良性病变的患者，回顾性分析患者临床信息。

结果

297例患者纳入本研究，占我院肺部病灶行肺部手术治疗患者的9.8%。197例(66.3%)患者因体检行LDCT筛查发现肺部病灶。肺部病变胸部CT影像学评估情况，可评估的323个病灶，平均长径为(17.9±12.1)mm，直径≥8 mm的占91.0%，实性最多见(212/323, 65.6%)，此类肺部病灶可有毛刺征(71/323, 22.0%)、分叶征(94/323, 29.1%)、胸膜牵拉征(81/323, 25.1%)、血管集束征(130/323, 40.2%)、空泡征(23/323, 7.1%)等，提示恶性病变的影像学特征。292例(98.3%)行电视辅助胸腔镜手术(video-assisted thoracoscopic surgery, VATS)，232例(78.1%)患者行肺楔形切除术，13例(4.4%)行肺段切除术，51例(17.2%)患者行肺叶切除术。4例(1.3%)患者出现手术并发症。术后病理类型前3位的是感染性疾病98例(33.0%)、炎性结节96例(32.3%)和错构瘤64例(21.5%)。

结论

因术前不能排除恶性而行手术切除的肺部良性病灶，影像学表现以实性病灶多见，但多具有提示恶性的影像学特征。VATS可作为一种明确病原病理的重要活检方式。此类病灶病理结果以感染性疾病和炎性结节最为常见，错构瘤第三。

The value of the air bronchogram sign on CT image in the identification of different solitary pulmonary consolidation lesions

The aim of the present study is to investigate the value of air bronchogram sign on computed tomography (CT) image in the differential diagnosis of solitary pulmonary consolidation lesions (SPLs).A total of 105 patients (including 39 cases of lung cancer, 43 cases of tuberculosis, and 23 cases of pneumonia) with SPLs were evaluated for the CT features of air bronchogram sign in this retrospective study. The shape and lumen of the bronchi with air bronchogram sign, the length of the involved bronchus with air bronchogram sign, the length of lesion on the same plane and direction, and the ratio between the length of the involved bronchus and that of the lesion were evaluated.In total, there were 172 segmental and subsegmental bronchi involved. There were 62 segmental and subsegmental bronchi involved among 39 lung cancer cases, 77 segmental and subsegmental bronchi involved among 43 tuberculosis cases, and 33 segmental and subsegmental bronchi involved among 23 pneumonia cases. The shape of the bronchi with air bronchogram sign was significantly different among lung cancer, tuberculosis, and pneumonia (P < .05). The lumen of the bronchi with air bronchogram sign was also significantly different among the 3 SPLs (P < .05). The length of the involved bronchus with air bronchogram sign and the ratio between the length of the involved bronchus and that of the lesion were significantly different between lung cancer and tuberculosis (P < .05), or between lung cancer and pneumonia (P < .05), but not between tuberculosis and pneumonia (P > .05). No significant difference was found in the length of lesion among the 3 SPLs (P > .05).The shape and lumen of the bronchi with air bronchogram sign can be used to distinguish lung cancer, tuberculosis, and pneumonia. The length of the involved bronchus with air bronchogram sign and the ratio between the length of the involved bronchus and that of the lesion can be used to distinguish lung cancer from tuberculosis and pneumonia.

Assessment of the cancer risk factors of solitary pulmonary nodules

There are no large samples or exact prediction models for assessing the cancer risk factors of solitary pulmonary nodules (SPNs) in the Chinese population. We retrospectively analyzed the clinical and imaging data of patients with SPNs who underwent computer tomography guided needle biopsy in our hospital from Jan 1st of 2011 to March 30th of 2016. These patients were divided into a development data set and a validation data set. These groups included 1078 and 344 patients, respectively. A prediction model was developed from the development data set and was validated with the validation data set using logistic regression. The predictors of cancer in our model included female gender, age, pack-years of smoking, a previous history of malignancy, nodule size, lobulated and spiculated edges, lobulation alone and spiculation alone. The Area Under the Curves, sensitivity and specificity of our model in the development and validation data sets were significantly higher than those of the Mayo model and VA model (p < 0.001). We established the largest sampling risk prediction model of SPNs in a Chinese cohort. This model is particularly applicable to SPNs > 8 mm in size. SPNs in female patients, as well as SPNs featuring a combination of lobulated and spiculated edges or lobulated edges alone, should be evaluated carefully due to the probability that they are malignant.