Analysis of pulmonary metastasis as an indication for operation: an evidence-based approach

Study Protocol for a Randomised Controlled Trial on Pulmonary Metastasectomy vs. Standard of Care in Colorectal Cancer Patients With ≥ 3 Lung Metastases (PUCC-Trial)

This is a multicentre prospective randomised controlled trial for patients with 3 or more resectable pulmonary metastases from colorectal carcinoma. The study investigates the effects of pulmonary metastasectomy in addition to standard medical treatment in comparison to standard medical treatment plus possible local ablative measures such as SBRT. This trial is intended to demonstrate an overall survival difference in the group undergoing pulmonary metastasectomy. Further secondary and exploratory endpoints include quality of life (EORTC QLQ-C30, QLQ-CR29 and QLQ-LC29 questionnaires), progression-free survival and impact of mutational status. Due to the heterogeneity and complexity of the disease and treatment trajectories in metastasised colorectal cancer, well powered trials have been very challenging to design and execute. The goal of this study is to create a setting which allows treatment as close to the real life conditions as possible but under well standardised conditions. Based on previous trials, in which patient recruitment in the given setting hindered successful study completion, we decided to (1) restrict inclusion to patients with 3 or more metastases (since in case of lesser, surgery will probably be the preferred option) and (2) allow for real world standard of care (SOC) treatment options before and after randomisation including watchful waiting (as opposed to a predefined treatment protocol) and (3) possibility that patient can receive SOC externally (to reduce patient burden). Moreover, we chose to stipulate 12 weeks of systemic treatment prior to possible resection to further standardize treatment response and disease course over a certain period of time. Hence, included patients will be in the disease state of oligopersistence rather than primary oligometastatic. The trial was registered in the German Clinical Trials Register (DRKS-No.: DRKS00024727).

Pulmonary Metastasectomy in Colorectal Cancer (PulMiCC) randomised controlled trial: a systematic review of published responses

OBJECTIVES

The objective of this review was to assess the nature and tone of the published responses to the Pulmonary Metastasectomy in Colorectal Cancer (PulMiCC) randomized controlled trial.

METHODS

Published articles that cited the PulMiCC trial were identified from Clarivate Web of Science (©. Duplicates and self-citations were excluded and relevant text extracted. Four independent researchers rated the extracts independently using agreed scales for the representativeness of trial data and the textual tone. The ratings were aggregated and summarized. Two PulMiCC authors carried out a thematic analysis of the extracts.

RESULTS

Sixty-four citations were identified and relevant text was extracted and examined. The consensus rating for data inclusion was a median of 0.25 out of 6 (range 0 to 5.25, IQR 0-1.5) and for textual tone the median rating was 1.87 out of 6 (range 0 to 5.75, IQR 1-3.5). The majority of citations did not provide adequate representation of the PulMiCC data and the overall the textual tone was dismissive. Although some were supportive, many discounted the findings because the trial closed early and was underpowered to show non-inferiority. Two misinterpreted the authors' conclusions but there was acceptance that five-year survival was much higher than widely assumed.

CONCLUSIONS

Published comments reveal a widespread reluctance to consider seriously the results of a carefully conducted randomized trial. This may be because the results challenge accepted practice because of 'motivated reasoning'. But there is a widespread misunderstanding of the fact that though PulMiCC with 93 patients was underpowered to test non-inferiority, it still provides reliable evidence to undermine the widespread belief in a major survival benefit from metastasectomy.

The Pulmonary Metastasectomy in Colorectal Cancer cohort study: Analysis of case selection, risk factors and survival in a prospective observational study of 512 patients

AIM

We wanted to examine survival in patients with resected colorectal cancer (CRC) whose lung metastases are or are not resected.

METHODS

Teams participating in the study of Pulmonary Metastasectomy in Colorectal Cancer (PulMiCC) identified potential candidates for lung metastasectomy and invited their consent to join Stage 1. Baseline data related to CRC and fitness for surgery were collected. Eligible patients were invited to consent for randomization in the PulMiCC randomized controlled trial (Stage 2). Sites were provided with case report forms for non-randomized patients to record adverse events and death at any time. They were all reviewed at 1 year. Baseline and survival data were analysed for the full cohort.

RESULTS

Twenty-five clinical sites recruited 512 patients from October 2010 to January 2017. Data collection closed in October 2020. Before analysis, 28 patients with non-CRC lung lesions were excluded and three had withdrawn consent leaving 481. The date of death was known for 292 patients, 136 were alive in 2020 and 53 at earlier time points. Baseline factors and 5-year survival were analysed in three strata: 128 non-randomized patients did not have metastasectomy; 263 had elective metastasectomy; 90 were from the randomized trial. The proportions of solitary metastases for electively operated and non-operated patients were 69% and 35%. Their respective 5-year survivals were 47% and 22%.

CONCLUSION

Survival without metastasectomy was greater than widely presumed. Difference in survival appeared to be largely related to selection. No inference can be drawn about the effect of metastasectomy on survival in this observational study.

Surgical Morbidity and Lung Function Changes After Laser-Assisted Pulmonary Metastasectomy: A Prospective Bicentric Study

Objective: The surgical resection of pulmonary metastases is associated with a survival benefit in selected patients. The use of laser devices for pulmonary metastasectomy (PM) is believed to facilitate the complete resection of metastases while preserving a maximum of healthy parenchyma. This is a prospective study to evaluate surgical outcome including the changes of lung function after laser–assisted surgery (LAS).

Methods: A total of 77 operations in 61 patients in which PM was carried out in a curative intent were analyzed. A 1.320 nm diode-pumped Nd: YAG-Laser was used for resection of the metastases. Surgical and clinical data were collected using a standardized form and postoperative lung function changes 3 and 6 months after surgery were assessed using whole body plethysmography and diffusion capacity for carbon monoxide (DLCO). Size and distance of metastases to the pleural surface were measured radiologically.

Results: A median of two metastases were resected per operation (range 1–13). The median duration of postoperative air leak was 1 day (range 0–11). LAS associated postoperative minor and major complications were observed in 4 (5%) cases and 1 (1%) case, respectively; there were no mortalities. The analysis of perioperative lung function showed that mean VC 3 months after surgery was reduced by 11 %, FEV1 by 11% and median DLCO by 11% (all p < 0.0001). There was almost no recovery of lung function between 3 and 6 months in the whole cohort. Patients with two or less metastases showed a recovery of lung function after 3 months regarding DLCO (p = 0.003). Decline of DLCO in the whole cohort correlated with the number of resected metastases at 3 months (r = 0.45, p = 0.006) and at 6 months (r = 0.42, p = 0.02) as well as depth of metastases in the parenchyma at 6 months (r = 0.48, p = 0.001).

Conclusions: LAS is a safe and effective method for PM even for higher numbers of metastases, with short duration of postoperative air leak and little morbidity. Number and depth, but not size of metastases affect lung function changes after resection.

The role of pulmonary metastasectomy for pulmonary metastasis from head and neck cancer

The incidence rate of distant metastasis from head and neck (HN) cancers is 4.2-58.8%. The lung is the most common site of distant metastasis, and pulmonary metastasectomy (PM) can be performed in selected patients with pulmonary metastasis originating from HN cancers. However, due to the small number of study objectives, the knowledge on PM treatment of pulmonary metastasis from HN cancers remains insufficient, and the optimal management of pulmonary metastasis from HN cancer is unclear. Patients with pulmonary metastasis from HN cancer who underwent PM have a better prognosis than those who did not, with reported 5-year overall survival rates after PM of 20.9-59.4%. A histology of squamous cell carcinoma, incomplete resection, a short disease-free interval (DFI), and the oral cancer have been identified as factors predicting a worse prognosis after PM in this patient population. As a systemic therapy, longer overall survival has been achieved using immune check point inhibitors compared with standard single-agent therapies. Since the clinical and morphological diagnoses of pulmonary metastasis from HN cancers are often difficult, molecular techniques can provide useful information for the differential diagnosis between pulmonary metastasis from HN cancers and primary lung cancers. In cases of suspected pulmonary metastasis from HN cancer, the surgical strategy should be determined based on the patient's clinical background.

Pulmonary metastasectomy for pulmonary metastasis of breast cancer has a limited prognostic impact: a multi-institutional retrospective analysis

Background

Pulmonary metastasectomy (PM) for breast cancer-derived pulmonary metastasis is controversial. This study aimed to assess the prognostic factors and implication of PM for metastatic breast cancer using a multi-institutional database.

Methods

Clinical data of 253 females with pulmonary metastasis of breast cancer who underwent PM between 1982 and 2017 were analyzed retrospectively.

Results

The median patient age was 56 years. The median follow-up period was 5.4 years, and the median disease-free interval (DFI) was 4.8 years. The 5- and 10-year survival rates after PM were 64.9% and 50.4%, respectively, and the median overall survival was 10.1 years. Univariate analysis revealed that the period of PM before 2000, a DFI <36 months, lobectomy/pneumonectomy, large tumor size, and lymph node metastasis were predictive of a worse overall survival. In the multivariate analysis, a DFI <36 months, large tumor size, and lymph node metastasis remained significantly related to overall survival. The 5- and 10-year cancer-specific survival rates after PM were 66.9% and 54.7%, respectively, and the median cancer-specific survival was 13.1 years. Univariate analyses revealed that the period of PM before 2000, DFI <36 months, lobectomy/pneumonectomy, large tumor size, lymph node metastasis, and incomplete resection were predictive of a worse cancer-specific survival. Multivariate analysis confirmed that a DFI <36 months, large tumor size and incomplete resection were significantly related to cancer-specific survival.

Conclusions

As PM has limited efficacy in breast cancer, it should be considered an optional treatment for pulmonary metastasis of breast cancer.

Morbidity, mortality, and survival in elderly patients undergoing pulmonary metastasectomy for colorectal cancer

PURPOSE

The number of elderly patients with colorectal cancer is increasing. Nevertheless, they are undertreated compared to younger patients. This study compares postoperative morbidity, mortality, survival, and morbidity risk factors of elderly and younger patients undergoing pulmonary metastasectomy (PM).

METHODS

We retrospectively analyzed our prospective database of 224 patients operated for colorectal lung metastases between 1999 and 2014. Two groups were defined to evaluate the influence of the patients' age (A: < 70 years; B: ≥ 70 years). Morbidity, mortality, and risk factors for morbidity were analyzed using χ²-test and Fisher's exact test. The Kaplan-Meier method, log-rank test, and multivariate Cox regression were used to assess survival and prognosticators.

RESULTS

Altogether, minor morbidity, major morbidity, and mortality were 17%, 5.8%, and 0%, respectively. Between groups A (n = 170) and B (n = 54), there was no difference in minor and major morbidity (p = 0.100) or mortality (0%). Heart arrhythmia was a risk factor for increased morbidity in group B (p = 0.007). The 5-, 10-, and 15-year survival rates were 43%, 30%, and 27%, respectively, in group A and 55%, 36 and 19%, respectively, in group B (p = 0.316). Disease-free interval ≥ 36 months (p = 0.023; OR 2.88) and anatomic resections (p = 0.022; OR 3.05) were associated with prolonged survival in elderly patients.

CONCLUSIONS

Morbidity, mortality, and overall survival after PM with lymphadenectomy for elderly patients were comparable to younger patients. A disease-free interval > 36 months and anatomic lung resections might be associated with prolonged survival. However, elderly patients should also be evaluated for a curative treatment.

Surgery for pulmonary metastases from colorectal cancer: survival and prognostic factors

Background

This study aimed to describe overall survival following pulmonary metastasectomy for colorectal cancer (CRC) in Sweden, and to assess the discrimination of a recently proposed risk prediction model.

Methods

Individual-level data of 756 patients who underwent resection of pulmonary metastases from CRC between 2009 and 2015 were obtained from ThoR, a Swedish national quality register for thoracic surgery. We classified patients into three risk categories according to the number of preoperative risk factors [age, disease-free interval (DFI), presence of extrathoracic lesions, number of pulmonary metastases] established in a prior study. We estimated the hazard ratios (HRs) and 95% confidence interval (CI) by Cox regression and the restricted mean survival time difference as group contrast measures.

Results

During a median follow-up time of 2.9 years, 35% (268/756) patients died. At 5 years, overall survival was 56% (95% CI: 51-60%). In a Cox regression model with risk category as the only independent variable, the HR for all-cause mortality was 1.94 (95% CI: 1.38-2.72, P<0.001) and 4.35 (95% CI: 2.49-7.62, P<0.001) in the moderate- (n=558) and high-risk categories (n=32), respectively, versus the low-risk category (n=166). At 5 years, the differences in restricted mean survival time were 6 months (P<0.001) and 1.5 years (P<0.001) in the moderate- and high-risk categories, respectively, versus the low-risk category.

Conclusions

Five-year survival after surgery for pulmonary metastases from CRC in Sweden was similar or higher compared with contemporary reports. A prognostic model, initially developed in Japanese patients, had excellent discrimination in an external validation cohort of Swedish patients.

The prognostic value of positron emission tomography/computed tomography in pulmonary metastasectomy

Background

Although positron emission tomography/computed tomography (PET/CT) findings are prognostic in lung cancer patients, the prognostic value of PET/CT findings in patients with pulmonary metastases has neither been comprehensively investigated nor clarified. The aims of this retrospective study were to evaluate the value of PET/CT and identify novel prognostic indicators for pulmonary metastasectomy.

Methods

Between May 2004 and February 2017, 178 patients underwent PET/CT and resection of pulmonary metastases. After exclusion of patients who underwent biopsy only or duplicate cases, 142 patients were analyzed. Prognostic indicators, including PET/CT findings and outcomes were investigated.

Results

The median follow-up time was 42 months. The primary tumor site was colorectal in 76, kidney in 14, head and neck in 13, breast in 12, stomach in 8, urinary tract in 7, and other organs in 12 patients. The median maximal standardized uptake value (SUV_max) was 4.6. The optimal cut-off value, determined by receiver operating characteristic (ROC) analysis, identified the following cut-off values: disease-free interval (DFI) (12 months; SUV_max =4.5). Univariable analysis revealed that DFI ≤12 months, incomplete resection, and SUV_max ≥4.5 were significant for poor outcome. Multivariable analysis revealed incomplete resection and SUV_max ≥4.5 were significant for poor outcome. The 5-year survival rates of patients with SUV_max ≥4.5 and SUV_max <4.5 were 51.6% and 74.0%, respectively.

Conclusions

Analysis of patients undergoing pulmonary metastasectomy demonstrated that incomplete resection and an SUV_max ≥4.5 are significant prognostic indicators. PET/CT findings should be included in estimations of these patients' prognosis.

Long-term survival after surgery for pulmonary metastases from colorectal cancer: an observational cohort study

Background

Evidence for pulmonary metastasectomy following colorectal cancer (CRC) is scarce. The aim of the study was to investigate long-term survival and identify prognostic factors to aid patient selection.

Methods

We included all patients who underwent pulmonary resections for CRC metastases between January 01, 2004 and December 31, 2015 in a population-based cohort study. The primary outcome measure was all-cause mortality and was ascertained from Swedish national registers. The Kaplan-Meier estimator was used to calculate cumulative survival. We used Cox regression for estimation of hazard ratios (HR) and 95% confidence intervals (CI) for the association between patient characteristics and survival.

Results

We included 184 patients. The number of procedures per year increased from 1 in 2004 to 34 in 2015. During a median follow-up time of 3.2 years, 36% (66/184) patients died. Overall survival at 5 years was 60% (95% CI: 50-68%) and was significantly lower compared to an age- and gender-matched Swedish population. Carcinoembryonic antigen (CEA) level was identified as a prognostic factor for mortality in the age and sex-adjusted analysis (HR, 2.46; 95% CI: 1.15-5.26, P=0.020).

Conclusions

We found a steady increase in the number of pulmonary metastasectomies after CRC during the study period. We identified prethoracotomy CEA level as a prognostic factor for long-term survival, which was consistent with prior reports. The 5-year overall survival rate in our study was 60%, which was high in comparison with prior reports. Although our results indicated that current patient selection criteria were reasonable, definitive evidence of efficacy is pending.

Pulmonary metastasectomy in uterine malignancy: outcomes and prognostic factors

Metastatic uterine cancer is a form of systemic disease. As for other solid tumours, it is advocated by some authors that in selected patients, lung metastasectomy may play a role in long-term disease control. The practice of lung metastasectomy is however open to criticism as there is lack of convincing evidence, and over-encouraging outcomes may be attributed to intrinsic selection bias. The case of metastatic uterine tumours is reviewed in the light of the available literature, in order to identify common patterns and prognostic factors that may influence and determine an individualised and informed patient decision.

Stage IV colorectal cancer primary site and patterns of distant metastasis

BACKGROUND

Although colorectal cancer (CRC) usually metastasizes to the liver and/or lungs, factors influencing the anatomic pattern of metastases remain poorly understood.

METHODS

We assessed the relationship between primary CRC site and pattern of synchronous metastasis among 1202 individuals diagnosed with incident metastatic CRC between 2010 and 2014 and identified through the Seattle-Puget Sound Surveillance, Epidemiology, and End Results (SEER) registry. Polytomous logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) for the association between primary tumor site and synchronous metastatic pattern.

RESULTS

Compared to patients with proximal colon primaries, patients with rectal primaries were more likely to present with lungs-only or liver and lungs metastases versus liver-only metastases (OR_{lungs-onlyvs.liver-only}: 2.39, 95% CI: 1.35-4.24, OR_{liver+lungsvs.liver-only}: 2.20, 95% CI: 1.46-3.32).

CONCLUSION

These findings suggest that patients with rectal primaries are more likely than patients with colon primaries to present with synchronous lung metastases.

Pulmonary Manifestations of Solid Non-Pulmonary Malignancies

The lungs are a common site of metastatic disease. Pulmonary metastases develop due to local blood flow and cellular or biochemical properties of tumor cells. Metastases develop from any type of malignancy and may occur via hematogenous, lymphatic, aerogenous, and/or direct spread. Metastatic disease may present with symptoms indistinguishable from primary lung cancer, including dyspnea, hemoptysis, and chest pain. Radiographically, these may present as parenchymal lung disease, mediastinal lymphadenopathy, airway obstruction, or pleural and vascular disease. No part of the thorax is spared from metastatic potential. This review highlights complications of non-pulmonary solid malignancies based on sites of anatomic metastases.