Surgical intervention for pulmonary metastases

Evaluation of Surgical Cases of Lung Cancer Admitted in Shiraz Referral Hospitals, Southern Iran in 2009-2022

INTRODUCTION

Globally, lung cancer is one of the most commonly diagnosed cancers and continues to take the lead in cancer-related mortality rates. This study aims to provide the latest statistics on the clinical, histopathological, and epidemiological features of lung cancer patients who underwent surgical resection in referral hospitals in Southern Iran.

METHOD

In this retrospective study, records of all patients with operable primary and secondary lung cancer who underwent surgical resection of the lung in Shiraz hospitals, located in Southern Iran from November 2009 to May 2022 were screened. Data on demographic, clinical, surgical, and pathological characteristics were analyzed by SPSS software.

RESULTS

A total of 232 patients with operable lung cancer, including 150 (64.7%) primary cases and 82 (35.3%) secondary cases, underwent 249 operations. The mean age of primary and secondary lung cancer patients was 56.70 ± 13.99 and 45.56 ± 18.88, respectively (p < 0.001). Males accounted for 54.0% and 58.5% of primary and secondary lung cancer patients, respectively. Adenocarcinoma was the most frequent primary pathology, while sarcomas were the most common metastatic lesions. The predominant presenting symptoms were cough (n = 75, 75.0%) and dyspnea (n = 31, 59.7%) in primary and secondary cases, respectively. Involvement of the right lung was more frequent in both groups (65.5% and 53.1% for primary and secondary cases respectively). The most commonly performed surgeries were lobectomy (69.9%) and limited resection (69.8%) for primary and secondary lesions, respectively. Cigarette smoking and extensive resection had a significant association with the in-hospital mortality rate (p = 0.012 and 0.009 respectively). The overall in-hospital mortality rate was 3.6% (n = 9).

CONCLUSION

Surgical interventions were mostly performed in men and histopathologic subtypes of primary lung adenocarcinoma, metastatic soft tissue sarcoma, and metastatic colon cancer. Smoking and extensive resection accompany a higher risk of short-term postoperative mortality.

[Resection of Solitary Lung Metastasis of Urinary Tract Transitional Cell Cancer Can Prolong Survival in Selected Patients]

There are only a few small published studies on pulmonary metastasectomy for urinary tract transitional cell carcinoma (TCC). In this study, we examined the long-term outcome and the prognostic survival factors associated with pulmonary metastasectomy of urinary tract TCC, as based on our centre's 20-year experience. Between 2000 and 2020, curative pulmonary metastasectomy was performed in 18 patients (14 males and 4 females). Clinical, demographical and surgical data were retrospectively analysed. The disease-free interval between treatment of the primary tumour and pulmonary metastasectomy ranged from one to 48 months. Survival analysis was conducted with the Kaplan-Meier method and log-rank test. The 3- and 5-year survival rates were 84.7% and 52.9%, respectively. Resection of solitary metastases was a positive and independent factor for survival (p = 0.04). Pulmonary metastasectomy of urinary tract TCC is associated with a favourable outcome and solitary metastasis is associated with long-term survival. Surgical resection of solitary pulmonary metastasis and repeated lung metastasectomy by pulmonary recurrence from a urinary tract TCC is feasible in selected patients.

Lung Metastatectomy: Can Laser-Assisted Surgery Make a Difference?

BACKGROUND

Resection of lung metastases with curative intention in selected patients is associated with prolonged survival. Laser-assisted resection of lung metastases results in complete resection of a high number of lung metastases, while preserving lung parenchyma. However, data concerning laser lung resections are scarce and contradictory. The aim of this study was to conduct a systematic review to evaluate the utility of laser-assisted pulmonary metastasectomy.

METHODS

An electronic search in MEDLINE (via PubMed), complemented by manual searches in article references, was conducted to identify eligible studies.

RESULTS

Fourteen studies with a total of 1196 patients were included in this metanalysis. Laser-assisted surgery (LAS) for lung metastases is a safe procedure with a postoperative morbidity up to 24.2% and almost zero mortality. LAS resulted in the resection of a high number of lung metastases with reduction of the lung parenchyma loss in comparison with conventional resection methods. Survival was similar between LAS and conventional resections.

CONCLUSION

LAS allows radical lung-parenchyma saving resection of a high number of lung metastases with similar survival to conventional methods.

Lung Resections for Elderly Patients with Lung Metastases: A Comparative Study of the Postoperative Complications and Overall Survival

Background: Pulmonary metastasectomy (PM) is an established treatment option for selected patients with stage IV solid tumors. The aim of this study was to investigate the feasibility of and survival rate in PM for elderly patients. Methods: We retrospectively analyzed all of the patients who underwent PM with curative intention at our institution. The patients were categorized into two groups: the elderly group (≥70 years old) and the non-elderly group (<70 years old). Results: The elderly group consisted of 222 patients versus 538 patients in the non-elderly group. The median number of resected metastases was 2 ± 3 in the elderly group and 4 ± 5 in the non-elderly group (p < 0.01). No difference in the rate of postoperative complications was observed between the two groups (p = 0.3). The median length of hospital stay in each group was comparable (10 ± 5 vs. 10 ± 4.3 days, p = 0.3). The 5-year survival rate was 67% in the elderly group and 78% in the non-elderly group (p = 0.117). In the univariate analysis, COPD was associated with poor survival in the elderly group (p = 0.002). Conclusion: The resection of pulmonary metastases in elderly patients is safe, is not associated with increased risks of postoperative complication, and the survival benefit is not reduced in selected patients.

An External-Validated Prediction Model to Predict Lung Metastasis among Osteosarcoma: A Multicenter Analysis Based on Machine Learning

BACKGROUND

Lung metastasis greatly affects medical therapeutic strategies in osteosarcoma. This study aimed to develop and validate a clinical prediction model to predict the risk of lung metastasis among osteosarcoma patients based on machine learning (ML) algorithms.

METHODS

We retrospectively collected osteosarcoma patients from the Surveillance Epidemiology and End Results (SEER) database and from four hospitals in China. Six ML algorithms, including logistic regression (LR), gradient boosting machine (GBM), extreme gradient boosting (XGBoost), random forest (RF), decision tree (DT), and multilayer perceptron (MLP), were applied to build predictive models for predicting lung metastasis using patient's demographics, clinical characteristics, and therapeutic variables from the SEER database. The model was internally validated using 10-fold cross-validation to calculate the mean area under the curve (AUC) and the model was externally validated using the Chinese multicenter osteosarcoma data. Relative importance ranking of predictors was plotted to understand the importance of each predictor in different ML algorithms. The correlation heat map of predictors was plotted to understand the correlation of each predictor, selecting the 10-fold cross-validation with the highest AUC value in the external validation ROC curve to build a web calculator.

RESULTS

Of all enrolled patients from the SEER database, 17.73% (194/1094) developed lung metastasis. The multiple logistic regression analysis showed that sex, N stage, T stage, surgery, and bone metastasis were all independent risk factors for lung metastasis. In predicting lung metastasis, the mean AUCs of the six ML algorithms ranged from 0.711 to 0.738 in internal validation and 0.697 to 0.729 in external validation. Among the six ML algorithms, the extreme gradient boosting (XGBoost) model had the highest AUC value with an average internal AUC of 0.738 and an external AUC of 0.729. The best performing ML algorithm model was used to build a web calculator to facilitate clinicians to calculate the risk of lung metastasis for each patient.

CONCLUSIONS

The XGBoost model may have the best prediction effect and the online calculator based on this model can help doctors to determine the lung metastasis risk of osteosarcoma patients and help to make individualized medical strategies.

Lung Metastases: Current Surgical Indications and New Perspectives

Pulmonary metastasectomy is an established treatment that can provide improved long- term survival for patients with metastatic tumor(s) in the lung. In this mini-review, we discuss the state of the art of thoracic surgery in surgical management of lung metastases which actually occurs for a large part of surgical activity in thoracic surgery department. We describe the principles of surgical therapy that have been defined across the time, and that should remain the milestones of lung metastases treatment: a radical surgery and an adequate lymphadenectomy. We then focus on current surgical indications and report the oncological results according to the surgical approach (open vs. mini-invasive), the histological type and number of lung metastases, and in case of re-metastasectomy. Finally, we conclude with a brief overview about the future perspectives in thoracic surgery in treatment of lung metastases.

Video-assisted pulmonary metastectomy is equivalent to thoracotomy regarding resection status and survival

Background

Surgical resection of pulmonary metastases leads to prolonged survival if strictly indicated. Usually, thoracotomy with manual palpation of the entire lung with lymph node dissection or sampling is performed. The aim of this study was to evaluate the role of video-assisted thoracoscopic surgery (VATS) in pulmonary metastectomy with curative intent.

Methods

In this study, all patients with suspected pulmonary metastasis (n = 483) who visited the Center for Thoracic Surgery in Regensburg, between January 2009 and December 2017 were analysed retrospectively.

Results

A total of 251 patients underwent metastectomy with curative intent. VATS was performed in 63 (25.1%) patients, 54 (85.7%) of whom had a solitary metastasis. Wedge resection was the most performed procedure in patients treated with VATS (82.5%, n = 52) and thoracotomy (72.3%, n = 136). Postoperative revisions were necessary in nine patients (4.8%), and one patient died of pulmonary embolism after thoracotomy (0.5%). Patients were discharged significantly faster after VATS than after thoracotomy (p < 0.001). Complete (R0) resection was achieved in 89% of patients. The median recurrence-free survival was 11 months (95% confidence interval 7.9–14.1). During follow-up, eight (12.7%) patients in the VATS group and 42 (22.3%) patients in the thoracotomy group experienced recurrence (p = 0.98). The median overall survival was 61 months (95% confidence interval 46.1–75.9), and there was no significant difference with regard to the surgical method used (p = 0.34).

Conclusions

VATS metastasectomy can be considered in patients with a solitary lung metastasis. An open surgical approach with palpation of the lung showed no advantage in terms of surgical outcome or survival.

Is repeated pulmonary metastasectomy justified?

Recurrence after pulmonary metastasectomy (PM) is frequent, but it is unclear to whom repeated pulmonary metastasectomy (RPM) offers highest benefits. Retrospective analysis of oncological and post-operative outcomes of consecutive patients who underwent PM from 2003 to 2018. Overall survival (OS) and disease-free interval (DFI) were calculated. Cox regression was used to identify variables influencing OS and DFI. In total, 264 patients (female/male: 114/150; median age: 62 years) underwent PM for colorectal cancer (32%), sarcoma (19%), melanoma (16%) and other primary tumors (33%). Pulmonary metastasectomy was approached by video-assisted thoracic surgery (VATS) in 73% and pulmonary resection was realized by non-anatomical resection in 76% of cases. The overall median follow-up time was 33 months (IQR 16–56 months) and overall 5-year survival rate was 62%. Local or distant recurrences were observed in 172 patients (65%) and RPM could be performed in 66 patients (25%) for a total of 116 procedures. RPM was realized by VATS in 49% and pulmonary resection by wedge in 77% of cases. In RPM patients, the 5-year survival rate after first PM was 79%. Post-operative cardio-pulmonary complication rate (13% vs. 12%; p = 0.8) and median length of stay (4 vs. 5 days; p = 0.2) were not statistically different between first PM and RPM. Colorectal cancer (HR 0.56), metachronous metastasis (HR 0.48) and RPM (HR 0.5) were associated with better survival. In conclusion, our results suggest that RPM offers favorable survival rates without increasing post-operative morbidity.

[The role of systemic therapy of lung metastases with lymph node involvement]

Modern systemic therapy with chemotherapy, targeted therapy and immunotherapy has led to a significant improvement in the overall survival in many tumor diseases over the past 15 years. Thus, the surgical treatment of lung metastases and lymph node metastases is not only valuable to achieve a cure for selected tumors but it can and must be used to eliminate tumor growth peaks in the case of a circumscribed progression. These can be an expression of tumor heterogeneity that cannot be achieved by systemic therapy. Depending on the dynamics and extent of the metastasis, the therapeutic approach must be individually decided in the tumor board.

Pulmonary metastasis of head and neck cancer: surgical removal outcomes from a tertiary care center

Purpose

There has been no clear data on the effectiveness of pulmonary metastasectomy on several original cancers, including head and neck. We aim to collect data about the metastasectomies performed in our center for eligible patients and elaborate more on predictors and prognosis.

Methods

A retrospective analysis of 56 patients who underwent metastasectomy from head and neck cancers at our facility between January 2000 and January 2016 (16 years). Statistical analysis was performed based on gender, disease-free interval (DFI), location of the original tumor, and histological subtypes to assess their effect and relevance to the prognosis and disease recurrence.

Results

Twenty-nine males and 27 females had lung metastasis from head and neck. The primary lesions of the lung metastasis were more often found in the thyroid (34%), followed by nasopharynx (32%). As for histology, the most common one was papillary cancer (34%), followed by squamous cell carcinomas (29%). The DFI was more than 2 years in 32 patients (57%). The survival rates were 79.5% at 3 years and 71.7% at 5 years. In the univariate analysis, histology was the only independent prognostic factor (p = 0.05). On the other hand, age (p = 0.6), DFI (p = 0.24), and site of the primary tumor (p = .06) showed no effect on the prognosis of head and neck cancers metastasizing to the lungs.

Conclusion

Pulmonary metastasectomy for lesions originating from head and neck provides good long-term survival. Histological subtype was the only statistically significant prognostic factor.

Pulmonary laser-assisted metastasectomy is associated with prolonged survival in patients with colorectal cancer

Background

Pulmonary metastases develop in 10-15% of patients with colorectal cancer. Surgical metastasectomy currently provides the only hope for a cure for these patients. The aim of this study was to analyze the expanding role of pulmonary metastasectomy in the context of laser-assisted surgery (LAS) vs. non-laser-assisted surgery (NLAS).

Methods

We performed a single-center retrospective analysis of 204 patients who underwent curative pulmonary metastasectomy for colorectal cancer between 01/2005 and 12/2016. The main endpoint was survival. The Kaplan-Meier method was applied for statistical analysis and survival rates were compared with the log rank test.

Results

Median follow-up was 53 months. A total of 267 metastases were resected in 154 operations in the NLAS group (median: 1) vs. 438 metastases in 122 operations in the LAS group (median: 5; P<0.0001). The interval between treatment of the primary tumor and the first pulmonary metastasectomy was significantly shorter in the LAS group (19 vs. 32 months; P=0.008). Anatomical resections were significantly reduced using LAS, 8% vs. 23% respectively. Despite more negative predictors in the LAS group, there was no statistically significant difference in overall disease-specific 5-year survival (70% LAS vs. 58% NLAS; P=0.18).

Conclusions

Survival after pulmonary metastasectomy has previously been shown to correlate with a low number of metastases and a longer disease-free interval. However, with the tissue-saving LAS technique complete resectability can be achieved in patients with more metastases and long-term survival is possible for selected patients.

The Past, Present and Future of Pulmonary Metastasectomy: A Review Article

Pulmonary metastases are a sign of advanced malignancy and an omen of poor prognosis. Once primary tumors metastasize, they become notoriously difficult to treat and interdisciplinary management often involves a combination of chemotherapy, radiotherapy, and surgery. Over the last 25 years, the emerging body of evidence has recognized the curative potential of pulmonary metastasectomy. Surgical resection of pulmonary metastases is now commonly considered for patients with controlled primary disease, absence of widely disseminated extrapulmonary disease, completely resectable lung metastases, sufficient cardiopulmonary reserve, and lack of a better alternative systemic therapy. Since the development of these selection criteria, other prognostic factors have been proposed to better predict survival and optimize the selection of surgical candidates. Disease-free interval (DFI), completeness of resection, surgical approach, number and laterality of lung metastases, and lymph node metastases all play a dynamic role in determining patient outcomes. There is a definite need to continue reviewing these prognosticators to identify patients who will benefit most from pulmonary metastasectomy and those who should avoid unnecessary loss of lung parenchyma. This literature review aims to explore and synthesize the last 25 years of evidence on the long-term survival, prognostic factors, and patient selection process for pulmonary metastasectomy.

Percutaneous computed tomography-guided permanent 125I implantation as therapy for pulmonary metastasis

Purpose

To evaluate intermediate-term outcomes after computed tomography (CT)-guided radioactive ¹²⁵I seed implantation (CTRISI), and to determine prognostic variables associated with outcomes in patients with pulmonary metastases.

Material and methods

Thoracic surgeons evaluated and performed implantation of ¹²⁵I radioactive seeds under CT guidance or combined with surgical resection. Patients were monitored in the thoracic surgery clinic for recurrence and survival.

Results

Fifty patients (31 men, 19 women; median age, 59 years; range, 16-85) underwent CTRISI. The primary cancer was colorectal in 10 (20%), malignant fibrous histiocytoma in 8 (16%), sarcoma in 5 (10%), renal in 4 (8%), and other in 22 (44%) patients. CTRISI was the sole treatment in 45 patients (90%) and was combined with surgical resection in 5 patients (10%). The actuarial D₉₀ of implanted ¹²⁵I seeds ranged from 90 to 160 Gy (median, 120 Gy). No procedurally related deaths occurred. At a median follow-up of 41.5 months (range, 7-74 months), 6 patients were alive. The median survival time was 42.1 months (95% confidence interval: 26.5-53.4), and the estimated 1-, 3-, and 5-year overall survival rates were 88.0%, 58.0%, and 26.7%, respectively. Lesion size was an important prognostic variable associated with overall and progression-free survival (p < 0.05).

Conclusions

CTRISI is safe in this group of patients with pulmonary metastases and provides reasonable results. Surgical resection remains the standard for resectable cases, but CTRISI offers an alternative for selected patients or may be used as a feasible approach in combination with surgical resection for selected patients.

Pulmonary metastasectomy in sarcoma-experiences with laser-assisted resection

Background

Previous data suggest a survival benefit in well selected patients with extrathoracic sarcoma after pulmonary metastasectomy. Different techniques have been described for pulmonary metastasectomy; however laser-assisted surgery (LAS) was suggested to provide the best outcome in patients with higher numbers of metastases.

Methods

Data were extracted from a prospectively maintained institutional database and a total of 83 patients who underwent pulmonary metastasectomy at our clinic in the last 11 years were identified.

Results

We analyzed a total of 106 operations of which LAS was performed in 46 and conventional resection in 60 cases. Significantly more metastases were resected in the LAS group compared to the conventional group [median, interquartile range (IQR): 6.5 (2.0-11.0) vs. 1.0 (1.0-3.5); P<0.0001]. Despite this difference the number of tumor recurrences was similar in both groups [64% tumor recurrences in the LAS group and 58% in the conventional group, odds ratio (OR) =1.3, P=0.6]. Furthermore, overall survival (OS) was comparable with a median survival of 77.6 and 29.0 months and 2- and 5-year survival rates of 71% and 63% as well as 53% and 36% in the respective cohorts [hazard ratio (HR) =0.74, P=0.43].

Conclusions

Using LAS a significantly higher number of metastases were removed while producing similar long-term results as compared to patients treated by other techniques. Expectably, recurrence rates in metastasized sarcoma patients remain high with either surgical method. Future studies will have to evaluate possible advantages provided by LAS in a prospective manner.

Sequential Treatment with Pazopanib and Everolimus in Metastatic Renal Cell Carcinoma

In metastatic renal cell carcinoma, complete response to first-line antiangiogenic agents is rare and resistance to therapy often develops. Protocols for sequential treatment with angiogenesis and mTOR inhibitors are under evaluation to improve outcomes. In this observational, real-world study, patients received a first-line therapy with pazopanib until discontinuation for disease progression or toxicity, then a second-line with everolimus. Primary endpoints were overall survival (OS) for sequence, progression free survival (PFS) for each agent, and safety. Thirty-one patients were included in the analysis: 73.3% of patients underwent nephrectomy before treatment, 25.8% had at least three comorbidities. At the beginning of therapy, the median age was 68 years, with more than 60% of patients older than 65 years. The median OS for sequence was 26.5 months (95% CI 17.4-nc); median PFS was 10.6 months (95% CI 6.3–12.1) with pazopanib and 5.3 months (95% CI 3.8–6.7) with everolimus. The median persistence in pazopanib therapy was 8.1 months (Interquartile Range IQR 5.3–12.7), with 31% of patients who required dose reduction, while persistence in everolimus was 4.4 months (IQR 3.4–6.5). Sequence was well tolerated with a different profile of adverse events for each agent. These data confirmed that pazopanib was effective, even in reduced dosing, and well tolerated and suggested that everolimus may represent an opportunity to continue a therapy when patients cannot further tolerate angiogenesis inhibitors or develop a resistance.

Evaluation of the diagnostic utility of endobronchial ultrasound-guided transbronchial needle aspiration for metastatic mediastinal tumors

Background and Objectives:

The mediastinum is a relatively uncommon site of distant metastases, which typically appear as peripheral lung nodules. We chose to assess the utility of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for the diagnosis of distant metastases to the mediastinum.

Materials and Methods:

Over the period 2008–2013, a total of 446 patients with concurrent or previously diagnosed and treated extrathoracic malignancies were evaluated.

Results:

Surgical treatment was carried out in 414 patients (156 women and 237 men aged 26–68 years, mean age of 56.5 years) presenting with distant metastases to the lungs: Thoracoscopic wedge resection was completed in 393 patients and lobectomy and segmentectomy were performed in 7 and 14 patients, respectively. The median time from primary tumor resection was 6.5 years (range: 4.5 months to 17 years). Thirty-two of these patients underwent EBUS-TBNA for mediastinal manifestation of the underlying disease. EBUS-TBNA specimens were aspirated from the subcarinal or right paratracheal lymph node stations in 26 (81%) patients and from the hilar lymph nodes in 6 (18.8%) patients only. Metastases to lymph nodes were confirmed in 14 of these patients (43.8%). Primary lung cancer was diagnosed in seven patients. Mediastinoscopy was performed in two patients to reveal either lymph node metastasis or sarcoidosis. Thoracotomy for pulmonary metastases resection and mediastinal lymph node biopsy was performed in nine patients. Lymph node metastasis was confirmed in five patients (15.6%). The diagnostic efficacy, sensitivity, specificity, and negative predictive value (NPV) of EBUS-TBNA were 78.8%, 93.3%, 100%, and 87.5%, respectively.

Conclusion:

EBUS-TBNA is a valuable diagnostic tool in a selected group of patients with secondary tumors in the mediastinum and lungs.

[Analysis of the Choice of Operation Mode and Prognosis Factors of Patients with Tumors of the Lung Metastasis]

背景与目的

肺部转移性肿瘤的治疗观念有所改变，外科手术的治疗价值及影响预后的因素值得探讨。

方法

回顾性分析2006年1月-2009年12月经手术治疗的57例肺部转移性肿瘤患者的临床资料，随访1年、3年、5年生存率，比较胸腔镜和常规开胸两种手术方式的差别，探讨患者性别、年龄、手术方式、无瘤生存间隔期（disease-free interval, DFI）、转移瘤数目、转移瘤大小及术后是否化疗与预后的关系。

结果

全组患者围手术期无死亡，患者术后1年、3年、5年生存率分别为81.3%、46.5%、29.2%，中位生存时间为33.8个月。多因素分析显示DFI、转移瘤数目和直径是影响预后的独立因素。

结论

合理选择手术治疗，能够提高肺部转移性肿瘤患者的生存期，胸腔镜是优选的手术方式，孤立性肺转移瘤及直径 < 4 cm的患者手术效果更佳。

Pulmonary resection and systemic lymph node dissection in a patient with breast cancer who had a 33-year disease-free interval

Objective

Breast cancer metastasis to the lung is common. The resection of lung metastases in patients with breast cancer has been controversial. Here, we present a very rare case of pulmonary and mediastinal lymph node metastases in a patient with breast cancer who had a disease-free interval (DFI) of more than 33 years.

Methods

An involved lobectomy and systematic mediastinal lymph node dissection were performed.

Results

The histological examination confirmed pulmonary metastasis from the breast cancer associated with mediastinal lymph nodes metastasis.

Conclusions

To our knowledge, this is the first case reported of a patient with a 33-year DFI after a radical mastectomy for breast cancer who presented with pulmonary metastasis with mediastinal lymph node involvement. This case indicates that a long-term follow-up of breast cancer patients is necessary. Systematic mediastinal lymph node dissection should be considered as a prognostic study during pulmonary metastasectomy for breast cancer.

Pulmonary and chest wall metastasectomy in urogenital tumors: a single center experience and review of literature

BACKGROUND

Pulmonary metastases are often found in advanced malignancies. Urogenital malignancies originating from kidney, prostate, testes, and bladder all metastasize preferentially to the lungs.

OBJECTIVES

This retrospective study aimed to evaluate the results of pulmonary and chest wall metastasectomy in patients with primary urogenital Tumors.

PATIENTS AND METHODS

The patients who underwent pulmonary metastasectomy in Ghaem Hospital from 1996 to 2011 were examined. Thirteen out of 79 patients referred for pulmonary metastasectomy to a single thoracic surgeon had metastases from urogenital tumors; two cases with metastasis from urogenital tumors were inoperable. We reviewed their demographic data and also clinicopathological features. Disease free interval (DFI) was defined as the time between the first curative surgery and the appearance of the signs and symptoms of pulmonary metastasis.

RESULTS

Among 11 patients who underwent surgery consisted of eight males and three females. Their metastasis originated from testis tumors (n = 5), renal cell carcinoma (RCC; n = 4), bladder tumor (n = 1), and prostate cancer (n = 1). Their mean age was 41.27 years (range, 21-67). The mean age of the patients with RCC and testis tumor at the time of diagnosing metastasis was 54 and 24.8 years, respectively. There were two other patients (a 62-year-old female and a 54-year-old male) with pleural effusion due to metastatic RCC whose tumor was inoperable because of their poor general condition and hence, were referred for chemotherapy.

CONCLUSIONS

Pulmonary metastasectomy is feasible in selected cases.

Airtightness of lung parenchyma without a closing suture after atypical resection using the Nd:YAG Laser LIMAX 120

OBJECTIVES

Lung metastases can be non-anatomically resected with a Nd:YAG Laser. It is recommended that the resected lung surface be sealed by slowly resorbable sutures. However, the lung tissue may be restricted by the sutures once it is re-ventilated. Thus, it was analysed whether the lung parenchyma is airtight after laser resection without suturing the defect.

METHODS

The pulmonary artery of unimpaired paracardial lung lobes of freshly slaughtered pigs (mean weight 46 g) was cannulated and rinsed out via a hypotonic saline-heparin solution (5000 IE) until the perfusate was clear of body fluid. The lobular bronchus was connected to an airtight ventilation tube (Fa. VYGON 520 3.5 oral tube) and ventilated pressure-controlled (PEEP + 5 cm H₂O, P₁ = 20 cm H₂O, frequency = 10/min) via a respirator. All lobes were perfused with Ringer solution at 42°C at normothermia and normotonia. In group 1 (n = 8), an atypical peripheral parenchymal resection (average resected surface: 2 × 2 cm(2)) and in group 2 (n = 8), a deep atypical parenchymal resection (average resected surface: 4 × 4 cm(2)) were performed with the Nd:YAG Laser LIMAX 120 (output power at 100 watts). After post-resection ventilation of 15 min, the resection surface was tested for airtightness and burst pressure.

RESULTS

All group 1 lobes tested airtight under pressure-controlled ventilation. The mean burst pressure was 34.4 mbar (SD ± 3.2 mbar). Six lobes of group 2 were also completely airtight. The remaining two lobes, however, revealed a serious parenchymal leak (score 3). This was caused by the cross-opening of a segmental bronchus, although the surrounding lung parenchyma was also airtight. The mean burst pressure of these lobes was 31.7 mbar (SD ± 4.08 mbar). There was no significant difference between the two groups (P = 0.12).

CONCLUSIONS

Peripheral lung defects after Nd:YAG Laser resection might not be sutured, since the laser-induced vaporization of the lung parenchyma seems to be initially airtight. These experimental data warrant confirmation in a controlled clinical study.

Comparison of local tissue damage: monopolar cutter versus Nd:YAG laser for lung parenchyma resection. An experimental study

OBJECTIVES

Lung metastases are non-anatomically resected while sparing as much parenchyma as possible. For this purpose, a few surgeons use the Nd:YAG Laser LIMAX 120, whereas the majority of surgeons use a monopolar cutter like the MAXIUM. The aim of this experimental study was to investigate which instrument causes less lung-tissue damage at the same power output.

METHODS

These experiments were conducted on left lungs (n = 6) taken from freshly slaughtered pigs. The laser and the monopolar cutter were fixed in a hydraulic mover. The laser was focused at a distance of 3 cm to the lung tissue and the monopolar cutter was fixed in pressure-free contact with the lung surface. Both instruments were manoeuvred at a speed of 5, 10 and 20 mm/s in a straight line at an output of 100 watts over the lung surface. The lung lesions that ensued were then examined macro- and microscopically. The same procedures were repeated at a distance of 1 cm creating parallel lesions in order to analyse the lung tissue in between the lesions for thermal damage. In addition, two implanted capsules in the lung tissue simulating a lung nodule were resected with either the laser or the monopolar cutter. The resection surfaces were then examined by magnetic resonance imaging and histology for tissue damage. Finally, we created a 2-cm wide mark on the lung surface to test the resection capacity of both instruments within 1 min.

RESULTS

The laser created sharply delineated lesions with a vaporization and coagulation zone without thermal damage of the surrounding lung tissue. With lowering the working speed, each zone was extended. At a working speed of 10 mm/s, the mean vaporization depth using the laser was 1.74 ± 0.1 mm and the mean coagulation depth was 1.55 ± 0.09 mm. At the same working speed, the monopolar cutter demonstrated a greater cutting effect (mean vaporization depth 2.7 ± 0.11 mm; P < 0.001) without leaving much coagulation on the resection surface (mean coagulation depth 1.25 ± 0.1 mm; P = 0.002). In contrast to the laser, the monopolar cutter caused thermal damage of the adjacent lung tissue. The adjacent tissue injury was detected in histological examination as well as in the MRI findings. Adjacent lung tissue after lung metastasectomy using the monopolar cutter was hyper-intensive in T2-weighted MR imaging, indicating a severe tissue damage. No significant changes in signal intensity were observed in T2-weighted imaging of the adjacent lung tissue after using the laser for lung resection. One minute of laser applied at a 100-watt output penetrated a lung surface area of 3.8 ± 0.4 cm(2) compared with 4.8 ± 0.6 cm(2) of surface after application of the monopolar cutter (P = 0.001).

CONCLUSIONS

The monopolar cutter possesses indeed a greater cutting capacity than the laser, but it also causes more adjacent tissue injury. Thus, laser resection might be preferred for lung metastasectomy.

Thermal ablation of malignant lung tumors

BACKGROUND

About 50 000 new cases of non-small-cell carcinoma of the lung are diagnosed in Germany each year. More than 20% of the affected patients cannot be offered radical resection because of comorbidity alone. The lung is also the second most common site of distant metastases of extrathoracic tumors; it is the only site of such metastases in 20% of cases. In recent years, image-guided thermoablation has been used with increasing frequency in patients who are unable to undergo surgery for medical reasons.

METHODS

The PubMed database was selectively searched for publications on the indications, complications, and results of the thermoablative techniques currently in clinical use, with special attention to radiofrequency ablation (RFA).

RESULTS

There is only a small evidence base to date concerning the treatment of malignant lung tumors with thermoablation. Retrospective and prospective case series have been published, but no randomized controlled trials have yet been conducted. RFA, the most common technique, involves the image-guided percutaneous placement of one or more probes in the tumor, to which thermal energy is then applied. For peripherally located tumors that measure less than 3 cm in diameter, local control of tumor growth can be achieved in about 90% of cases. The long-term results that are now available from smaller series provisionally indicate 5-year survival rates of 20% to 61%. The most common complication is pneumothorax requiring drainage, which occurs in about 10% of cases. In the intermediate term, thermoablation does not cause any clinically relevant loss of pulmonary function.

CONCLUSION

Image-guided thermoablation cannot now be considered an alternative to surgery for the treatment of malignant lung tumors with curative intent. It does, however, widen the spectrum of therapeutic options for patients who are medically unable to undergo a surgical procedure.