Feasibility of mathematical models to predict success in video-assisted thoracic surgery lung nodule excision

[Clinical Application of Vectorial Localization of Peripheral Pulmonary Nodules Guided by Electromagnetic Navigation Bronchoscopy in Thoracic Surgery]

背景与目的

随着计算机断层扫描技术（computed tomography scans, CT）的广泛应用，越来越多的肺小结节被发现，一些需要外科手术处理的结节数量也在增加。胸腔镜手术中对于不可直视及触摸到的肺外周小结节的准确定位较为困难。虽然目前一些常用的定位技术能够带来比较好的定位效果，如CT引导的穿刺定位和电磁导航支气管镜（electromagnetic navigation bronchoscopy, ENB）系统引导的亚甲兰染色定位，但同时仍存在着气胸、出血及定位不准确的问题。ENB引导的矢量定位法是我中心首创的一种新型定位技术，该技术避免了前两种

方法

可能出现的胸膜损伤或者定位区域扩大的问题，为ENB引导的定位技术提供了一定的指导。本文回顾性分析胸腔镜术前通过ENB引导矢量定位的临床结果来确定该方法的临床应用价值。方法回顾性分析2017年10月-2018年10月于青岛大学附属医院胸外科行ENB矢量定位法进行胸腔镜手术前定位的患者资料，统计患者临床资料、肺小结节影像学特征，评估该方法临床应用的安全性及有效性。

结果

我们成功实施了22例患者的22个肺外周结节在ENB引导下矢量定位和腔镜下楔形切除（22/22, 100%）。结节平均大小为（11.0±3.6）mm，距脏层胸膜表面距离为（16.5±6.2）mm；ENB系统显示屏导航定位装置（locatable guide, LG）与病灶距离为（14.5±10.1）mm，离体标本标记与病灶距离为（15.3±11.0）mm，ENB矢量定位平均时间为（17.5±4.2）min，无定位点LG发生移位（0.0%）。手术过程无中转开胸（0.0%），患者术中及术后未见明显并发症（0.0%），术后平均住院时间为（3.8±1.2）d，无围手术期患者死亡（0.0%）。术后病理结果为恶性肿瘤者19例，均得到了完全切除。

结论

我们应用ENB引导的矢量定位法在肺外周小结节术前定位和微创切除的初步经验提示该方法安全、可行、有效，可作为ENB操作中可选的一种定位方式。胸外科临床医师可以进一步研究该方法并应用到临床操作中。

Prediction of lung tumor palpability using high-resolution computed tomography

BACKGROUND

Palpation is the most important means of locating lung tumors and resecting them with sufficient margins. This study aimed to predict the palpability of pulmonary lesions using high-resolution computed tomography.

METHODS

Eighty-six pulmonary lesions were palpated in fresh resected lung specimens from July 2013 to March 2014. The following parameters were compared between 10 impalpable and 76 palpable lesions: maximum tumor size in pulmonary and bone window level settings, consolidation tumor size in pulmonary window level setting, and pleural-tumor distance. In 54 adenocarcinomas, the lepidic component and fibrosis foci rates were compared between the two groups.

RESULTS

Tumor size in bone window level setting and the consolidation tumor size were significantly smaller in the impalpable group (both p < 0.001), and an operational cutoff of 5 mm was identified by receiver-operating characteristic analysis (sensitivity/specificity was 90.0%/94.7% and 90.0%/86.9%, respectively). Pulmonary lesions were impalpable with 87.5% probability when the tumor size in bone window level setting was ≤ 5 mm and the pleural-tumor distance was ≥ 5 mm, and with 85.7% probability when the consolidation tumor size was ≤ 5 mm and the pleural-tumor distance was ≥ 5 mm. Lepidic component and fibrosis foci rates of impalpable/palpable lesions were 96.0%/52.8% and 4.0%/24.7%, respectively (both p < 0.001).

CONCLUSIONS

Tumor size in bone window level setting or a consolidation tumor size ≤ 5 mm and pleural-tumor distance ≥ 5 mm are simple criteria that are potentially useful indicators for preoperative marking to locate small-sized lepidic-predominant adenocarcinomas with few fibrotic foci.

Videothoracoscopic identification of chondromatous hamartoma of the lung

Introduction

The main disadvantage of a videothoracoscopic procedure is the lack of touch sensation. The probability of easily finding the lesion is usually estimated according to computed tomography (CT).

Aim

To find useful parameters of location of chondromatous hamartoma of the lung parenchyma in relation to its size to assess the probability of successful search via a videothoracoscopic approach only.

Material and methods

A group of 55 patients operated on for chondromatous hamartoma of the lung at the First Department of Surgery in Olomouc from January 2006 to June 2011 was analyzed. Initially, the tumor's longest diameter and its nearest distance to the pleural surface were measured on CT scans. Subsequently, the surgery began using the videothoracoscopic approach. A short thoracotomy with direct palpation followed when videothoracoscopy failed.

Results

No significant differences in age, sex and side of localization between the group with and without successful videothoracoscopic detection were found. A significant difference was found in the median size (p = 0.026) and the depth of the tumor (p < 0.0001) and in the calculated index “tumor size/depth” (p < 0.0001). Deeper analysis revealed that the parameters “depth” and “index size/depth” are considered to be good predictors but the parameter “size” is not a suitable predictor.

Conclusions

The main predictors of successful videothoracoscopic detection of lung chondromatous hamartoma are considered to be the depth of the tumor in the lung parenchyma with a cut-off value ≤ 7.5 mm and the index “size/depth” with a cut-off value ≥ 1.54; the tumor size is not considered to be a good predictor.

[Locating pulmonary nodules with a computed axial tomography-guided harpoon prior to videothoracoscopic resection. Experience with 52 cases]

OBJECTIVE

Videothoracoscopic (VTC) resection of peripheral pulmonary nodules (PN) occasionally requires performing a mini-thoracotomy to locate them using palpation. The aim of this study is to evaluate the usefulness of inserting a CT-guided harpoon as a method for locating PN prior to surgery.

MATERIAL AND METHODS

A study was conducted on a total of 52 patients who were scheduled for locating 55 PN prior to surgery by inserting a CT-guided harpoon, from November 2004 to January 2011.

RESULTS

Of the 52 patients, of whom 35 had a history of cancer, 31 were male and 21 were female, with ages between 28 and 84 years (mean: 62.2 years) with a PN <20mm (mean: 9.57mm). A total of 55 harpoons were inserted (3 patients had 2 simultaneous harpoons). Using the VTC it was observed that 52 harpoons were correctly anchored to the PN. There were no complications. In the group of 35 patients with an oncology history, the nodules were malignant in 26 cases (74.3%), and there were 17 (70.6%) with malignant PN in those with no oncology history. The hospital stay varied between 4 and 72h, with 19 patients (36.5%) included in a one-day surgery program.

CONCLUSIONS

The preoperative identification of peripheral pulmonary nodules enables them to be removed directly with VTC. The insertion of a CT-guided harpoon in the PN is a safe and effective procedure that can be performed in a one-day surgery program.

Toracoscopia aplicada à ressecção de fragmento pulmonar com o auxílio de sutura mecânica em eqüinos

Este trabalho visou à ressecção de fragmento dorsocaudal do lobo pulmonar caudal esquerdo com o auxílio de sutura mecânica por via toracoscópica. Foram utilizados 10 eqüinos clinicamente sadios, os quais foram sedados e mantidos em estação. O procedimento foi realizado no hemitórax esquerdo, por três acessos previamente programados: o primeiro acesso foi no 12º espaço intercostal (EIC), o segundo no 14º, 15º ou 16º EIC e o terceiro no 14º ou 15º EIC, conforme a necessidade de posicionamento dos instrumentos. Em todos os animais foi possível controlar o pneumotórax, sendo observada evolução clínica satisfatória durante o período pós-operatório, exceto em um animal. Os resultados obtidos indicam que, por meio da videotoracoscopia, pode-se realizar ressecção pulmonar parcial com uso de sutura mecânica em eqüinos e seu emprego na rotina hospitalar poderá contribuir para melhor compreensão e controle de enfermidades sediadas na cavidade torácica.

Surgical and Nonsurgical Therapy for Lung Metastasis: Indications and Outcomes

The management of pulmonary metastasis is a broad and multifaceted topic. Because of the filtration function and the favorable microenvironment of the lung, most malignancies cause pulmonary metastases. This article focuses on recent experience with secondary lung malignancies and their newer treatment options, indications, and technical aspects.

A strategy for thoracoscopic resection of small pulmonary nodules

BACKGROUND

Preoperative procedures are often necessary to localize pulmonary nodules during thoracoscopic resection in order to reduce the necessity of resorting to thoracotomy. The aim of this report is to describe the strategy we developed to limit preoperative techniques without reducing the thoracoscopic success rate of localization.

METHODS

Between January 2000 and December 2003, 183 patients underwent video thoracoscopic resection of small pulmonary nodules. The patients were divided into two groups on the basis of the radiological features of the nodule. The subjects in group 1 were operated on directly, and endothoracic ultrasonography was performed when necessary. The subjects in group 2 underwent preoperative radionuclide labeling of the nodule.

RESULTS

In group 1, 112 out of 119 nodules (94%) were localized. Twenty-five out of 32 lesions, neither visible nor palpable, were found by endothoracic ultrasonography. In group 2, we localized 62 out of 64 nodules (97%).

CONCLUSIONS

Currently, we cannot completely avoid preoperative labeling techniques for thoracoscopic resection of small pulmonary nodules. However, correct patient selection may limit this necessity, without an increased conversion rate to thoracotomy, if endothoracic ultrasonography is available.

Indication for preoperative localization of small peripheral pulmonary nodules in thoracoscopic surgery

OBJECTIVE

Widespread clinical use of helical computed tomography has improved the detection rate for small peripheral pulmonary nodules. As a result, use of thoracoscopic surgery to confirm the diagnosis of small peripheral pulmonary nodules has become more important than ever before. However, if small peripheral pulmonary nodules are too small or located too deeply to detect thoracoscopically, it is necessary to mark the small peripheral pulmonary nodules preoperatively. The purpose of this study was to determine indications for preoperative hookwire marking in thoracoscopic resection of small peripheral pulmonary nodules.

METHODS

A total of 120 patients underwent thoracoscopic pulmonary resection in our institute from 1999 to 2001. Small peripheral pulmonary nodules were marked preoperatively in 61 of these patients by means of percutaneous placement of a hookwire under computed tomographic guidance. The hookwire-marked small peripheral pulmonary nodules either were smaller than 10 mm or were located more than 10 mm below the pleural surface.

RESULTS

Although 9 of the hookwire-marked small peripheral pulmonary nodules were easily identified during thoracoscopy, the other 52 small peripheral pulmonary nodules could not have been identified during thoracoscopy without the hookwire marking. Of the 59 small peripheral pulmonary nodules that were not hookwire marked, 7 required conversion to thoracotomy to locate the nodules. Small peripheral pulmonary nodules from both groups were examined and assigned to either an undetectable or detectable group. Discriminant function analysis indicated that a linear function (ie, depth = 0.836 x size - 2.811) could be used to differentiate between undetectable and detectable small peripheral pulmonary nodules, and preoperative hookwire marking for small peripheral pulmonary nodules should be considered for nodules in the region above those.

CONCLUSION

The results suggest that this formula might serve as an indication for preoperative marking of small peripheral pulmonary nodules in thoracoscopic resection.

Video-assisted thoracoscopic surgery for small indeterminate pulmonary nodules: indications for preoperative marking

STUDY OBJECTIVE

To determine the indications for preoperative localization of a small indeterminate pulmonary nodule.

DESIGN

In this retrospective study, univariate and multivariate analyses were performed by the logistic regression procedure.

SETTING

A single National Cancer Center Hospital in Japan.

PATIENTS

A series of 92 consecutive patients who underwent video-assisted thoracoscopic surgery (VATS) at our institute between 1993 and 1996.

INTERVENTIONS

The frequency and reasons for conversion to thoracotomy were assessed retrospectively. All preoperative CT scans were reviewed for eight radiologic features by two of the authors. These data were entered into univariate and multivariate analyses to identify the significant risk factors for a failure to detect a pulmonary nodule.

MEASUREMENTS AND RESULTS

Fifty patients (54%) needed conversion to a thoracotomy. The most common reason for the conversion was failure to localize nodules (46%). Univariate and multivariate analyses of 11 variables revealed one significant risk factor in the failure to detect nodules: distance to the nearest pleural surface (p < 0.05). Tumor size on radiograph remained marginally significant (p = 0.065) in multivariate analyses. If the distance to the pleural surface was > 5 mm in cases of nodules < or = 10 mm in size, the probability of failure to detect a nodule was 63%.

CONCLUSIONS

Our results suggested the indications for preoperative localization of a peripheral pulmonary nodule. Preoperative marking for a small indeterminate pulmonary nodule should be considered when the distance to the nearest pleural surface is > 5 mm in cases of lung nodules of < or = 10 mm in size.