The prognosis of pulmonary metastasectomy depends on the location of the primary colorectal cancer

Factors associated with receipt of pulmonary metastasectomy in patients with lung-limited metastatic colorectal cancer: Disparities in care and impact on overall survival

OBJECTIVES

Pulmonary metastasectomy (PM) for colorectal cancer may provide respite from systemic therapy and prolonged disease-free intervals. We sought to identify factors associated with PM and to characterize the differential impact on overall survival for those offered lung resection.

METHODS

The National Cancer Database was queried for stage IV colorectal cancer patients with lung-limited metastatic disease between 2010 and 2016. Among patients who underwent primary tumor resection, those who underwent PM were compared with those who did not. Penalized regression with the least absolute selection and shrinkage operator was used to determine factors associated with receiving metastasectomy as well as overall survival.

RESULTS

In total, 867 (15.1%) patients underwent resection of both primary tumor and pulmonary metastases whereas 4864 (84.8%) had primary tumor resection alone. In unadjusted analyses, metastasectomy patents were younger, more often privately insured, more educated, and traveled farther to receive care (all P < .001). In multivariable analyses, younger age, traveling >25 miles, and care at high-volume hospitals were associated with PM (P < .01). In addition, primary site surgery without PM was associated with worse overall survival (hazard ratio, 1.35; confidence interval, 1.23-1.49), even after adjusting for patient, tumor, and hospital-related factors.

CONCLUSIONS

Patients who were older, who received care closer to home, and who were treated at low-volume hospitals were less likely to receive metastasectomy for lung-limited colorectal cancer after definitive resection of their primary tumor. Failure to receive PM resulted in worse overall survival, emphasizing the strong need for efforts to provide uniform, equitable care to all patients.

Sublobar Resection, Stereotactic Body Radiation Therapy, and Percutaneous Ablation Provide Comparable Outcomes for Lung Metastasis-Directed Therapy

BACKGROUND

Prolonged survival of patients with metastatic disease has furthered interest in metastasis-directed therapy (MDT).

RESEARCH QUESTION

There is a paucity of data comparing lung MDT modalities. Do outcomes among sublobar resection (SLR), stereotactic body radiation therapy (SBRT), and percutaneous ablation (PA) for lung metastases vary in terms of local control and survival?

STUDY DESIGN AND METHODS

Medical records of patients undergoing lung MDT at a single cancer center between January 2015 and December 2020 were reviewed. Overall survival, local progression, and toxicity outcomes were collected. Patient and lesion characteristics were used to generate multivariable models with propensity weighted analysis.

RESULTS

Lung MDT courses (644 total: 243 SLR, 274 SBRT, 127 PA) delivered to 511 patients were included with a median follow-up of 22 months. There were 47 local progression events in 45 patients, and 159 patients died. Two-year overall survival and local progression were 80.3% and 63.3%, 83.8% and 9.6%, and 4.1% and 11.7% for SLR, SBRT, and PA, respectively. Lesion size per 1 cm was associated with worse overall survival (hazard ratio, 1.24; P = .003) and LP (hazard ratio, 1.50; P < .001). There was no difference in overall survival by modality. Relative to SLR, there was no difference in risk of local progression with PA; however, SBRT was associated with a decreased risk (hazard ratio, 0.26; P = .023). Rates of severe toxicity were low (2.1%-2.6%) and not different among groups.

INTERPRETATION

This study performs a propensity weighted analysis of SLR, SBRT, and PA and shows no impact of lung MDT modality on overall survival. Given excellent local control across MDT options, a multidisciplinary approach is beneficial for patient triage and longitudinal management.

Contemporary Outcomes for the Curative Treatment of Colorectal Cancer Pulmonary Metastases

PURPOSE

Treatment of pulmonary metastases (PM) from colorectal cancer (CRC) is the standard of care by several guidelines from Europe and the USA, but the validity of this strategy has been recently questioned, and the available evidence supporting this strategy is weak. We report the outcomes of a curative intent strategy in a very recent and homogenous series of patients.

METHODS

We did a retrospective review of all curative intent surgical or ablative treatment of PM from CRC performed consecutively in 3 French institutions from January 2015 to December 2019. Demographics, clinicopathological, and molecular characteristics were evaluated. Cox regression models were used to identify prognostic factors related to local recurrence and disease-free survival.

RESULTS

Records from 152 patients were reviewed. One-hundred thirty-five patients (88%) had surgical metastasectomy. Median age was 67 years. Most of the patients had a single lesion (66%), and 16% had synchronous PM. Eighty-one patients (53%) experienced recurrence, and the thorax was the most common site of recurrence. Median disease-free survival and overall survival were 35 months and 78 months after PM treatment. At the end of the study, only 17% of the patients died. Pulmonary tumor burden was correlated with disease-free survival in univariate analysis, but multivariate analysis did not find any prognostic factor independently associated with local recurrence or survival.

CONCLUSION

Our finds corroborate existing recommendation for the invasive treatment of PM from CRC in selected patients.

Survival outcomes of lung metastases from colorectal cancer treated with pulmonary metastasectomy or modern systemic chemotherapy: a single institution experience

BACKGROUND

Although pulmonary metastasectomy is an accepted treatment strategy for resectable lung metastases (LM) from colorectal cancer (CRC), its survival benefits are controversial. In contrast, recent advancements in chemotherapy have significantly improved metastatic CRC prognosis. This study aimed to evaluate survival outcome of LM from CRC in the age of newly developed chemotherapy.

METHODS

We retrospectively reviewed 50 patients who underwent complete resection and 22 patients who received chemotherapy as definitive treatment for LM from resected CRC at our hospital. The present study was limited to patients who started treatment for isolated LM after molecular targeted drugs became available in Japan.

RESULTS

Overall survival (OS), cancer-specific survival (CSS), disease-free survival (DFS) rates after pulmonary resection were 64.5%, 66.4%, and 32.6% at five years, respectively. OS and CSS rates of chemotherapy patients were 26.8% and 28.3% at five years, with a median progression-free survival time of 10.0 months. When compared the characteristics of surgical and chemotherapy patients, patients with pN factors of CRC (p = 0.013), smaller size (p < 0.001), larger number (p < 0.001), and bilateral (p < 0.001) LM received chemotherapy. Univariate analysis showed that multiple LM and rectal lesions were poor prognostic factors for OS (p = 0.012) and DFS (p = 0.017) in surgical patients, and rectal lesions were a poor prognostic factor for OS (p = 0.013) in chemotherapy patients.

CONCLUSIONS

Pulmonary metastasectomy showed a favorable survival in patients with LM from CRC. Despite the high recurrence rate after metastasectomy and recent advances in chemotherapy, surgical resection could still be considered as a valid option among multidisciplinary treatments.

TRIAL REGISTRATION

The research plan was approved by the Institutional Review Board of Shinko Hospital (No. 2142) on February 7, 2022.

The Management of Oligometastatic Disease in Colorectal Cancer: Present Strategies and Future Perspectives

Oligometastatic disease has been described as an intermediate clinical state between localized cancer and systemically metastasized disease. Recent clinical studies have shown prolonged survival when aggressive locoregional approaches are added to systemic therapies in patients with oligometastases. The aim of this review is to outline the newest options to treat oligometastatic colorectal cancer (CRC), also considering its molecular patterns. We present an overview of the available local treatment strategies, including surgical procedures, stereotactic body radiation therapy (SBRT), thermal ablation, as well as trans-arterial chemoembolization (TACE) and selective internal radiotherapy (SIRT). Moreover, since imaging methods provide crucial information for the early diagnosis and management of oligometastatic CRC, we discuss the role of modern radiologic techniques in selecting patients that are amenable to potentially curative locoregional treatments.

Pulmonary Metastasectomy

The lung represents the most common site for metastatic spread of extrathoracic primary malignancies. Pulmonary metastatic disease occurs in a wide breadth of cancers with a multitude of histologies, and, historically, has been managed predominantly with systemic therapy. However, in appropriately selected patients, pulmonary metastasectomy can provide extended disease-free intervals, relief from systemic therapy, and prolonged survival. Thus, pulmonary metastasectomy serves a vital role in the armamentarium against a multitude of primary malignancies. Moreover, as systemic agents improve and more patients live longer with stage IV cancer, pulmonary metastasectomy will likely have increasing relevance in the future.

Lung Metastasectomy from Colorectal Cancer, 10-year Experience in a South American Cancer Center

Purpose

This study aimed to describe the survival outcomes and factors associated with prognosis in patients undergoing pulmonary metastasectomy with colorectal cancer (CRC) in a cancer center in South America.

Material and methods

A retrospective analysis of patients that underwent lung metastasectomy due to CRC at National Cancer Institute (INC), Colombia between 2007 and 2017 was performed and Kaplan-Meier survival analysis along with log-rank test and Cox regression multivariate analysis were completed.

Results

Seventy-five patients with colorectal adenocarcinoma were included in the study. Of them, 57.3% were women with a median age of 62 years [interquartile ranges (IQR): 18.5]. For 45.3% the adenocarcinoma was located in the rectum and 29.3% had stage IV at diagnosis. 56% had a history of controlled extrapulmonary metastasis and 20% of the cases had a history of the metastasis of the liver. The median follow-up was 36.8 months (IQR: 27.4). Three-year and five-year overall survival (OS) was 57.5% [95% confidence interval (CI), 47.0–70.4] and 33.2% (95% CI, 23.4–47.2), respectively. Patients with bilateral, more than one pulmonary metastasis, abnormal postmetastasectomy carcinoembryonic antigen (CEA), history of liver metastasis, and disease-free interval (DFI) ≤12 months had worse OS. Three-year and five-year disease-free survival (DFS) was 30.1% (95% CI, 20.8–43.6) and 21.6% (95% CI, 13.0–35.9), respectively. Bilateral, more than one pulmonary metastasis, and patients with stage IV at diagnosis had the worst DFS. Multivariate analysis in the Cox regression model showed that abnormal postmetastasectomy CEA [Hazard Ratio (HR):1.97, 95% CI, 1.01–3.86, p = 0.045] and DFI ≤ 12 months (HR: 3.08, 95% CI, 1.26–7.53, p = 0.014) were independent factors for worst OS.

Conclusions

The OS found falls within the wide range described in the world literature but interestingly it falls at the bottom end of this range. The factors associated with worst survival were identified as bilateral, more than one pulmonary metastasis, abnormal postmetastasectomy CEA, history of liver metastasis, and DFI ≤12 months.

Contribution to the field

Pulmonary metastasectomy is the standard of care in patients with metastatic CRC. However, the literature supporting this conduct is based on retrospective studies and the only randomized controlled trial conducted to date was stopped due to poor recruitment. Limited information is available in South America about survival and factors associated with prognosis in patients with metastatic CRC. While this study is another series that adds to the many studies across the world that describe the use of pulmonary metastasectomy in CRC, it presents critical data as it is one of the few studies carried out in South America. As described in a wide range of world literature, OS found falls in patients that underwent lung metastasectomy due to CRC however; interestingly, in the South American population analyzed here it falls at the bottom end of this range. This may be explained by a large number of patients included with a history of extrapulmonary metastasis as well as may reflect inadequate patient access to reference cancer centers in Colombia. Factors associated with worst survival in our population were bilateral, more than one pulmonary metastasis, abnormal postmetastasectomy CEA, history of liver metastasis, and interval from diagnosis to development of pulmonary metastasis ≤12 months.

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.

Imaging Characteristics and Prognostic Value of Isolated Pulmonary Metastasis from Colorectal Cancer Demonstrated with18F-FDG PET/CT

Objective. Solitary pulmonary lesions (SPNs) in patients with a history of colorectal cancer (CRC) may be attributed to metastatic lung tumors, primary lung cancer, or benign nodules. We aimed to analyze the imaging characteristics of SPNs in CRC patients to differentiate these pulmonary nodules and evaluate the prognostic value of isolated pulmonary metastasis from CRC using 18F-FDG PET/CT. Methods. From January 2013 to January 2021, 62 CRC patients with SPNs demonstrated with 18F-FDG PET/CT were retrospectively enrolled in the present study. We compared the radiological and clinical characteristics of these patients. In addition, survival time and prognostic factors were statistically analyzed using the Kaplan-Meier method and multivariable Cox proportional hazards models. Results. There were 33 cases of isolated lung metastasis, 20 cases of second primary lung cancer (SPLC), and nine cases of benign nodules. The proportion of nodules with a maximal diameter greater than the median value was lower in the isolated lung metastasis group compared with the SPLC group ( $p<0.05$ ), showing polygonal shape, ill-defined margin, pleural indentation, air bronchogram, speculation, and ground-glass opacity. Patients with isolated lung metastasis had a significantly higher maximal diameter of lung lesion, SUVmax of lung lesion, and 18F-FDG uptake compared with the benign nodule group ( $p<0.05$ ). Multivariate analysis revealed that the following two factors were significant independent predictors of PLC: air bronchogram (hazard ratio [HR] =22.327; 95% confidence interval [CI]: 1.910-261.061; $p=0.013$ ) and spiculation (HR =6.148; 95% CI 1.469-25.725; $p=0.013$ ). Initial TNM stage IV (HR =19.831, 95% CI 1.061-370.782; $p=0.046$ ) was extremely associated with a decreased lifespan of CRC patients with isolated lung metastasis. Conclusions. The result showed that CT features, including air bronchogram and spiculated margins, could be used to differentiate SPLC from single isolated lung metastasis in CRC patients. In patients with isolated lung metastasis, primary CRC TNM stage IV was associated with a poorer prognosis, and patients with such conditions might need more care.

New Frontiers in Management of Early and Advanced Rectal Cancer

It is important to understand advances in treatment options for rectal cancer. We attempt to highlight advances in rectal cancer treatment in the form of a systematic review. Early-stage rectal cancer focuses on minimally invasive endoluminal surgery, with importance placed on patient selection as the driving factor for improved outcomes. To achieve a complete pathologic response, various neoadjuvant chemoradiation regimens have been employed. Short-course radiation therapy, total neoadjuvant chemotherapy, and others provide unique advantages with select patient populations best suited for each. With a clinical complete response, a "watch and wait" non-operative surveillance has been introduced with preliminary equivalency to radical resection. Various modalities for total mesorectal excision, such as robotic or transanal, have advantages and can be utilized in select patient populations. Tumors demonstrating solid organ or peritoneal spread, traditionally defined as unresectable lesions conveying a terminal diagnosis, have recently undergone advances in hepatic and pulmonary metastasectomy. Hepatic and pulmonary metastasectomy has demonstrated clear advantages in 5-year survival over standard chemotherapy. With the peritoneal spread of colorectal cancer, HIPEC with cytoreductive therapy has emerged as the preferred treatment. Understanding the various therapeutic interventions will pave the way for improved patient outcomes.

A multicenter LArge retrospectIve daTabase on the personalization of Stereotactic ABlative Radiotherapy use in lung metastases from colon-rectal cancer: the LaIT-SABR study

INTRODUCTION

stereotactic ablative radiotherapy (SABR) has been shown to increase survival in oligometastatic disease, but local control of colorectal metastases remains poor. We aimed to identify potential predictive factors of SBRT response through a multicenter large retrospective database and to investigate the progression to the polymetastatic disease (PMD).

MATERIAL AND METHODS

the study involved 23 centers, and was approved by the Ethical Committee (Prot. Negrar 2019-ZT). 1033 lung metastases were reported. Clinical and biological parameters were evaluated as predictive for local progression-free survival (FLP). Secondary end-point was the time to the polymetastatic conversion (tPMC).

RESULTS

Two-year FLP was 75.4%. Two-year FLP for lesions treated with a BED <100 Gy, 100-124 Gy, and ≥125 Gy was 76.1%, 70.6%, and 94% (p=0.000). Two-year FLP for lesion measuring ≤10 mm, 10-20 mm, and >20 mm was 79.7%, 77.1%, and 66.6% (p=0.027). At the multivariate analysis a BED ≥125 Gy significantly reduced the risk of local progression (HR 0.24, 95%CI 0.11-0.51; p=0.000). Median tPMC was 26.8 months. Lesions treated with BED ≥125 Gy reported a significantly longer tPMC as compared to lower BED. The median tPMC for patients treated to 1, 2-3 or 4-5 simultaneous oligometastases was 28.5, 25.4, and 9.8 months (p=0.035).

CONCLUSION

The present is the largest series of lung colorectal metastases treated with SABR. The results support the use of SBRT in lung oligometastatic colorectal cancer patients as it might delay the transition to PMD or offer relatively long disease-free period in selected cases. Predictive factors were identified for treatment personalization.

The impact of primary tumor location on prognosis after colorectal lung metastasectomy

PURPOSE

Currently, right colon cancer (RCC), left colon cancer (LCC), and rectal cancer (REC) are typically seen as different tumor entities. It is unknown if this subdivision by primary tumor location has an influence on the survival of patients with colorectal pulmonary metastasectomy (PM).

METHODS

We retrospectively analyzed our prospective database of 233 patients operated on for colorectal lung metastases between 1999 and 2014. Differences in the patient characteristics and the primary tumor and metastatic tumor burden were analyzed using χ2-tests. The long-term survival after PM of the three groups was analyzed with the Kaplan-Meier method and log-rank tests.

RESULTS

In total, PM was performed for 37 patients with RCC, 57 patients with LCC, and 139 patients with REC. Patients with LCC were significantly more likely to have UICC stage IV primary tumor (44.2% LCC vs. 37.5% RCC vs. 22.8% REC, p = 0.012) and significantly more likely to have a history of additional liver metastases (45.6% LCC vs. 32.4% RCC vs. 27.3% REC, p = 0.046). The 5-year survival rates after PM for patients with RCC, LCC, and REC were 47, 66, and 39%, respectively (p = 0.001). The median survival times of patients with RCC, LCC, and REC were 55 months (95% CI: 42.2-66.8), 108 months (95% CI: 52.7-163.3), and 44 months (95% CI: 50.4-63.6), respectively.

CONCLUSIONS

This study demonstrated a prognostic impact of the primary tumor localization in patients undergoing PM for colorectal lung metastases. Nevertheless, long-term survival was achievable in all groups.

The Assessment of Prognostic Factors for Lung Metastasectomy in Colorectal Cancer Patients With Previously Resected Liver Metastases

The purpose of this study is to investigate the prognostic factors of lung metastasectomy in patients with previously resected liver metastases. Thirty-three patients underwent complete resection of lung metastases after previous liver metastasectomy from colorectal cancer between January 2004 and December 2013. In univariate analyses, all cumulative survival curves were estimated using the Kaplan-Meier method, and differences in variables were evaluated using the log-rank test. Multivariate analyses were performed using the Cox proportional hazards regression model. The 5-year survival rate of all 33 patients after lung metastasectomy was 31%. Univariate analysis identified 2 significant prognostic factors: preoperative serum carcinoembryonic antigen level (P = 0.035) and maximum tumor size (P = 0.029). Subgroup analysis with a combination of these 2 independent prognostic factors revealed 2-year survival rates of 100%, 92.3%, and 0% for patients with 0, 1, and 2 risk factors, respectively. We identified 2 independent poor prognostic factors for pulmonary metastasectomy in patients with previously resected liver metastases: high serum carcinoembryonic antigen level before lung metastasectomy, and maximum size of lung metastases. When these 2 factors are combined, higher- and lower-risk subgroups can be identified, which may help select patients with previously resected liver metastases who benefit most from lung metastasectomy.

Outcomes and Prognostic Factors of Patients with Metastatic Colorectal Cancer Who Underwent Pulmonary Metastasectomy with Curative Intent: A Brazilian Experience

BACKGROUND

We aimed to identify clinicopathological and molecular features associated with progression-free survival (PFS) and overall survival (OS) after pulmonary metastasectomy for metastatic colorectal cancer in a retrospective cohort in Brazil.

MATERIALS AND METHODS

We did a retrospective review of thoracic surgeries performed in a single large academic hospital in Brazil from January 1985 to September 2019. Demographics, previously described prognostic factors, and clinicopathological and molecular characteristics were abstracted. Univariate Cox regression was performed for each variable, and, when significant, data were dichotomized to provide clinically meaningful thresholds.

RESULTS

Records from 698 patients were reviewed. Fifty-eight patients underwent pulmonary metastasectomy with curative intent. Of those, 53.4% had a single metastatic lesion. The median size of the largest lesion was 1.5 cm. Results of RAS, RAF, and mismatch repair testing and of cytokeratin 20 (CK20) and CDX2 testing were available for 13.8% and 58.6% of the sample, respectively. Median PFS was 14 months, median OS was 58 months, and 5-year survival was 49.8%. Unfavorable prognostic factors for OS included disease-free interval (DFI) <24 months, synchronous presentation, size of the largest lesion ≥2 cm, and loss of CK20 expression. Presenting with more than one lesion was prognostic for PFS but not for OS.

CONCLUSION

In this Brazilian cohort, our findings corroborate existing data supporting DFI, synchronous presentation, and number and size of lesions as prognostic factors. Furthermore, we found that loss of CK20 expression may be associated with more aggressive disease and shorter OS. Additional molecular prognostic factors after pulmonary metastasectomy for colorectal cancer should be further explored.

IMPLICATIONS FOR PRACTICE

This study consolidates disease-free interval, synchronous presentation, and number and size of lesions as clinically relevant data that may help guide therapy for patients with colorectal cancer and lung metastases who are candidates for curative-intent metastasectomy. Additionally, in this sample, lack of cytokeratin 20 expression in metastases was associated with shorter progression-free survival and overall survival, suggesting that biomarkers also may have a role in guiding therapy in this setting and that additional biomarkers should be further explored.

Metastases in locally advanced rectal cancer undergoing curatively intended treatment

BACKGROUND

The main cause of mortality in locally advanced rectal cancer (LARC) is metastatic progression. The aim of the present study was to describe frequency, pattern and outcome of metastatic disease in a cohort of LARC patients after curative resection.

METHODS

This was a single-centre cohort study of 628 LARC cases after neoadjuvant chemoradiotherapy/radiotherapy (CRT/RT) and surgery. Data, including the first site of metastasis, was registered in an institutional database linked to the National Cancer Registry.

RESULTS

Metastases were diagnosed in 270 patients (43.0%) with liver and lungs as the first site in 113 and 96 cases, respectively. Involved resection margins, high tumour stage and poor response to CRT/RT were associated with metastasis development and inferior overall survival (OS). Metastasectomy was performed in 76 (67.3%) patients with liver metastases and 28 (29.2%) patients with lung metastases. Five-year OS was 89% in patients without metastases and 32% in metastatic cases. In patients selected for metastasectomy, 5-year OS was 69% and 53% for lung and liver metastases, respectively. Corresponding numbers without metastasectomy were 12% and 0%.

CONCLUSION

In this large LARC cohort undergoing curatively intended treatment, liver and lung metastases occurred at similar frequencies. Liver as the first metastatic site was associated with inferior long-term outcome, while selection for metastasectomy was associated with better OS, with more than half of the resected patients being alive five years after LARC surgery. Our results show that the presence of resectable metastatic disease at diagnosis should not exclude a curative therapeutic approach in LARC.

Pulmonary metastasectomy in colorectal carcinoma

Colorectal cancer (CRC) is one of the leading causes of cancer-related deaths worldwide. It is estimated that 50% of all patients with CRC develop metastases, most commonly in the liver and the lung. Lung metastases are seen in approximately 10–15% of all patients with CRC. A large number of these patients with metastatic CRC can only receive palliative treatment due to invasion of other organs and disseminated disease. However, a subset of these patients present with potentially resectable metastases. Pulmonary metastasectomy is considered to be a potentially curative treatment for selected patients with resectable metastatic CRC. Current data suggest that patients that undergo pulmonary metastasectomy have 5-year survival rates of approximately 40%. However, the majority of data published regarding lung metastasectomy is based on small, retrospective case series. Due to this lack of prospective data, it is still unclear which subset of patients will benefit most from curative-intent surgery. Furthermore, there is also controversy regarding which prognostic and genetic factors are related to survival outcomes and whether there is a difference between open and thoracoscopic approaches in terms of overall and disease-free survival. In this review, we aim to summarize the latest data on prognostic factors and survival outcomes after pulmonary metastasectomy in patients with metastatic CRC.

Genomic profiling of colorectal cancer with isolated lung metastasis

BACKGROUND

Metastasis is a major cause of failed colorectal cancer (CRC) treatment. While lung metastasis (LM) is observed in 10-15% of patients with CRC, the genetic mechanisms that cause CRC to metastasize to the lung remain unclear.

METHODS

In this study, we employed whole exome sequencing (WES) of primary CRC tumors and matched isolated LM lesions to compare their genomic profiles. Comprehensive genomic analyses of five freshly frozen primary tumor lesions, five paired LM lesions, and matched non-cancerous tissues was achieved by WES.

RESULTS

An integrated analysis of somatic mutations, somatic copy number alterations, and clonal structures revealed that genomic alterations were present in primary and metastatic CRCs with various levels of discordance, indicating substantial levels of intertumor heterogeneity. Moreover, our results suggest that the founder clone of the primary tumor was responsible for the formation of the metastatic lesion. Additionally, only a few metastasis-specific mutations were identified, suggesting that LM-promoting mutations might be pre-existing in primary tumors.

CONCLUSIONS

Primary and metastatic CRC show intertumor heterogeneity; however, both lesions were founded by the same clone. These results indicate that malignant clones contributing to disease progression should be identified during the genetic prognosis of cancer metastasis.

Surgery versus stereotactic radiotherapy for treatment of pulmonary metastases. A systematic review of literature

It is not clear as to which is the best treatment among surgery and stereotactic radiotherapy (SBRT) for lung oligometastases. A systematic review of literature with a priori selection criteria was conducted on articles on the treatment of pulmonary metastases with surgery or SBRT. Only original articles with a population of patients of more than 50 were selected. After final selection, 61 articles on surgical treatment and 18 on SBRT were included. No difference was encountered in short-term survival between pulmonary metastasectomy and SBRT. In the long-term surgery seems to guarantee better survival rates. Mortality and morbidity after treatment are 0–4.7% and 0–23% for surgery, and 0–2% and 4–31% for SBRT. Surgical metastasectomy remains the treatment of choice for pulmonary oligometastases.

Patients with metastatic cancer with a limited number of deposits may benefit from surgical removal or irradiation of tumor nodules in addiction to chemotherapy. Surgical resection has been demonstrated to improve survival and, in some cases, can be curative. Stereotactic radiotherapy is emerging as a less invasive alternative to surgery, but settings and implications of the two treatments are profoundly different. The two techniques show similar results in the short-term, with lower complications rates for radiotherapy, while in the long-term surgery seems to guarantee higher survival rates.

Pulmonary metastasectomy for colorectal cancer: Prognosis analysis disaggregated by the origin of the primary tumor

BACKGROUND

The metastatic pattern differs between colon cancer and rectal cancer because of the distinct venous drainage systems. It is unclear whether colon cancer and rectal cancer are associated with different prognostic factors based on the anatomic difference.

METHODS

We assessed the prognostic factors and survival outcomes of patients with colorectal cancer who underwent pulmonary metastasectomy (PM), disaggregated by the location of primary colorectal cancer. The Cox proportional hazards model was used to identify variables that influenced the outcomes of pulmonary metastasectomy.

RESULTS

Between 2008 and 2017, 179 patients underwent PM classified into colon cancer and rectal cancer groups based on the site of origin of metastasis. The median postoperative follow-up was 2.3 years (range, 0.1-10.6). The post-PM 5-year survival rate in the colon cancer and rectal cancer groups was 42.5% and 39.9%, respectively (p = 0.310). On multivariable Cox proportional hazards analysis, presence of previous liver metastasis [hazard ratio (HR), 2.32; 95% confidence interval (CI), 1.19-4.51; p = 0.013], numbers of tumors (≥2; HR, 6.56; 95% CI, 2.07-20.79; p = 0.001), and abnormal preoperative carcinoembryonic antigen (CEA) level (HR, 2.50; 95% CI, 1.34-4.64; p = 0.001) were independent prognostic factors in patients with metastatic rectal cancer.

CONCLUSIONS

Prognostic correlates of post-PM survival differ between colon and rectal cancer. Rectal cancer patients have worse prognosis if they have a history of liver metastasis, multiple pulmonary metastases, or abnormal preoperative CEA. These results may help assess the survival benefit of PM and facilitate treatment decision-making.

Lung metastasectomy after colorectal cancer: prognostic impact of resection margin on long term survival, a retrospective cohort study

BACKGROUND

Pulmonary metastasectomy is considered a potentially curative treatment for selected patients with metastatic colorectal cancer (CRC). Several prognostic factors have been analysed, but to date, it is still not well defined which is the optimal resection margin during lung metastasectomy (LM). This study analyses the long-term results and prognostic factors after LM in CRC patients with particular attention to the resection margins. Primary endpoint of this study is to assess the correlation between resection margins and long-term outcomes.

METHODS

Observational cohort study on all proven cases of CRC lung metastases (2000-2016) resected with curative intent in a single centre.

RESULTS

The series included 210 consecutive patients (M/F 133/77) with a mean age of 65.4 (± 9.96) years, 75% (159/210) of them with a solitary metastasis. Mean size of metastasis was 2.57 cm (± 1.45). One hundred sixty-eight patients underwent wedge resections (80%) and lymphadenectomy was carried out in 90 cases (42.9%). With a mean follow-up of 56 months (range 5-192), we observed a 1-, 3- and 5-year overall survival (OS) of 95%, 74% and 54%, respectively. The patients were divided into three groups according to the resection margin distance from the tumour: (a) ≥ 2 cm (145 cases); (b) < 2, ≥ 1 cm (37 cases); and (c) < 1 cm (12 cases). The OS was significantly different between the three groups (p = 0,020); univariate and multivariate analyses showed that a narrow resection margin was an independent prognostic factor of worse survival (p = 0.006 and HR 3.4 p = 0.009).

CONCLUSIONS

Long-term survival of patients after LM is strongly associated with a greater distance between the lesion and the resection margin.

Pulmonary metastasis in newly diagnosed colon-rectal cancer: a population-based nomogram study

BACKGROUND

Colorectal cancer (CRC) has a high worldwide incidence with a tendency to metastasize to the lungs. We aimed to identify clinical factors related to lung metastasis (LM) and analyze the prognosis of patients after LM.

METHODS

Multivariate logistic regression analysis was used to identify risk factors for LM from CRC. Univariate and multivariate Cox proportional hazard models were performed to identify potentially important prognostic factors for patients with LM.

RESULTS

Age (p = 0.010), tumor size (p < 0.001), T stage (p < 0.001), N stage (p < 0.001), race (p < 0.001), tumor site (p < 0.001), liver metastasis (p < 0.001), brain metastasis (p < 0.001), bone metastasis (p < 0.001), serum levels of carcinoembryonic antigen (CEA) (p < 0.001), and circumferential resection margin (CRM) (p < 0.001) were associated with a risk of LM from CRC. All factors (all, p < 0.001) except tumor size (p = 0.095) and race (p = 0.650) were related to the overall survival of patients. Two nomograms were formulated to visually predict lung metastasis risk and 1-, 3-, and 5- year overall survivals for patients with LM. The concordance indices were 0.754 and 0.749, respectively.

CONCLUSIONS

Age, tumor size, histological grade, serum levels of CEA, tumor site, surgery modalities of CRC, CRM, number of positive lymph nodes, and chemotherapy were independent risk factors for LM from CRC. The nomograms we developed can be effectively used to forecast the risk of LM and predict the survival for LM from CRC.

Expert consensus on multidisciplinary therapy of colorectal cancer with lung metastases (2019 edition)

The lungs are the second most common site of metastasis for colorectal cancer (CRC) after the liver. Rectal cancer is associated with a higher incidence of lung metastases compared to colon cancer. In China, the proportion of rectal cancer cases is around 50%, much higher than that in Western countries (nearly 30%). However, there is no available consensus or guideline focusing on CRC with lung metastases. We conducted an extensive discussion and reached a consensus of management for lung metastases in CRC based on current research reports and the experts' clinical experiences and knowledge. This consensus provided detailed approaches of diagnosis and differential diagnosis and provided general guidelines for multidisciplinary therapy (MDT) of lung metastases. We also focused on recommendations of MDT management of synchronous lung metastases and initial metachronous lung metastases. This consensus might improve clinical practice of CRC with lung metastases in China and will encourage oncologists to conduct more clinical trials to obtain high-level evidences about managing lung metastases.

Metastatic Profile of Colorectal Cancer: Interplay Between Primary Tumor Location and KRAS Status

BACKGROUND

Mutant KRAS tumors are purported to metastasize differently than wild-type KRAS tumors. The biological heterogeneity of tumors from different parts of the colon are also reported to affect metastasis. This study aims to characterize the metastatic profile by evaluating these factors in unison.

METHODS

Retrospective analysis of 899 patients with metastatic colorectal cancers treated from January 2010 to December 2014 was conducted. KRAS mutation status and primary tumors location were correlated with single-site metastasis (liver, lung, and peritoneum) and dual-site metastases (liver-peritoneum, liver-lung, and lung-peritoneum). Patients without KRAS analyses were excluded.

RESULTS

Right-sided tumors had highest frequency of peritoneal metastasis as compared to left-sided or rectal tumors (34.7% versus 15.8% versus 8.8%, P = 0.00) regardless of KRAS status (32.6% versus 38.5%, P = 0.62). Left-sided tumors with wild-type KRAS had greater proportion of liver metastasis (78.6% versus 53.5%, P = 0.00), whereas those with mutant KRAS had greater proportion of lung metastasis (23.3% versus 8.7%, P = 0.02). Rectal tumors with wild-type KRAS tend to spread to the liver (81.4% versus 48.0%, P = 0.00) and not to the peritoneum (2.3% versus 20.0%, P = 0.01). In dual-site metastases, left-sided tumors with wild-type KRAS had more liver-peritoneal metastases (75.0% versus 29.4%, P = 0.00), whereas mutant KRAS had greater lung-liver metastases (64.7% versus 20.8%, P = 0.01). Rectal tumors had the predilection for lung-liver metastases as compared to right-sided and left-sided tumors (92.3% versus 40.0% versus 39.0%, P = 0.00) regardless of KRAS status (100% versus 75%, P = 0.12).

CONCLUSIONS

Our results may streamline surveillance programs based on primary tumor location and KRAS mutational status.

The Role of CXCL12 Axis in Lung Metastasis of Colorectal Cancer

This study aimed to explore the mechanism of lung metastases of colorectal cancer. The expression of CXCR4, CXCR7, and CXCL12 in colorectal cancer and lung metastases was analyzed by the immunohistochemical (IHC) method. Further, the study aimed at getting new insights into the role of CXCL12 in lung metastasis. A total of 41 patients who underwent surgical resections for both colorectal cancer and lung metastasis were retrospectively selected for this study. Also, 41 patients who underwent lung resection for benign lung disease were selected as the control group. In the in vivo experiment, the mice were injected with exosomes isolated from CT26. The mice with and without injection were sacrificed 3 weeks later. The lung tissue was analyzed by the IHC method and quantitative real-time PCR. The expression of CXCR7 and CXCL12 was significantly higher in lung metastases than in paired primary lesions. The expression of CXCL12 was significantly higher in the noncancerous lung tissue of patients with CRC than in patients with benign lung disease. Also, the expression of CXCL12 in the lung was higher in mice with exosome education. The results inferred that the expression of CXCR7 and CXCL12 was significantly higher in lung metastases than in primary tumors. Their combination could promote colorectal cancer lung metastasis. The expression of CXCL12 was elevated before metastasis. And this effect was induced by exosomes.

Surgical treatment of pulmonary metastasis in colorectal cancer patients: Current practice and results

Colorectal cancer (CRC) is a frequently occurring disease, yet diagnosed at a local stage in only 40% of cases. Lung metastases (LM) appear in 5-15% of patients and, left untreated, carry a very poor prognosis. Some CRC patients may benefit from a potentially curative LM resection, but success and benefit are difficult to predict. We discuss prognostic factors of survival after lung metastasectomy in CRC patients under several scenarios (with/ without prior liver metastases; repetitive pulmonary resections). We reviewed all studies (2005-2015) about pulmonary metastases surgical management with curative intent in CRC patients, with a minimum threshold on the number of patients reported (without prior liver metastases: n ≥ 100; with prior resection of liver metastases: n ≥ 50; repetitive thoracic surgery: n ≥ 30). The picture of the prognostic factors of survival is nuanced: surgical management demonstrates clear successes and steady progress, yet there is no single success criterion; stratification of patients and selection bias impact the conclusions. Surgical management of liver and lung metastases may prolong life or cure CRC patients, provided the lesions are fully resected and patients carefully selected. Repeat lung metastasectomy is a safe approach to treat patients in selected cases. In conclusion, there is no standard for surgical management in CRC patients with pulmonary metastases. Patients with isolated unilateral lung metastasis with normal CEA level and no lymph node involvement benefit the most from surgery. Most series report good results in highly selected patients, but instances of long-term disease-free survival remain exceptional.

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.

Post-pulmonary metastasectomy prognosis after curative resection for colorectal cancer

Purpose

We aimed to compare disease-free survival after pulmonary metastasectomy to that after hepatic metastasectomy, and to identify prognostic factors after pulmonary metastasectomy.

Results

Between 2005 and 2015, 129 patients underwent resection of isolated metachronous lung metastases from colorectal cancer. Three-year DFS after pulmonary metastasectomy was similar to that after hepatic metastasectomy (50.7% vs. 45.5%, respectively; p=0.58). Rectal cancer (hazard ratio [HR]: 2.04, 95% confidence interval [CI]: 1.09–3.79; p=0.03) and ≥2 metastases (HR: 2.17, 95% CI: 1.28–3.68; p=0.004) were independent adverse risk factors associated with disease-free survival after pulmonary metastasectomy on multivariate analysis. Three-year DFS for colon vs. rectal cancer patients was 72.5% vs. 42.6%, respectively (p=0.04). The number of lung metastases was an independent risk factor for DFS after pulmonary metastasectomy in rectal cancer patients.

Patients and Methods

Patients who underwent lung metastasectomy after curative resection of colorectal cancers were investigated. Disease-free survival (DFS) after pulmonary metastasectomy was compared to that after hepatic metastasectomy, which has a relatively well-known prognosis. Multivariate Cox proportional hazards analysis was performed to identify clinical variables predictive of survival after pulmonary metastasectomy.

Conclusions

Disease-free survival rates after resection of lung vs. liver metastases arising from colorectal cancers are similar. However, lung metastases specifically from rectal cancers produce poorer DFS rates. Primary tumor location must be considered for pulmonary metastasis treatment and follow-up in colorectal cancer patients.

Outcomes of segmentectomy and wedge resection for pulmonary metastases from colorectal cancer

Objectives

Although wedge resection is the most common surgical procedure for pulmonary metastases from colorectal cancer, there are few reports about segmentectomy for colorectal metastasectomy.

Methods

This was a subset analysis of a Japanese nationwide retrospective study of resected pulmonary metastases from colorectal cancer. The study included 553 patients who underwent segmentectomies ( n  = 98) or wedge resections ( n  = 455) without preoperative chemotherapy between January 2004 and December 2008. Recurrence patterns, recurrence-free survival and overall survival were analysed for each procedure.

Results

As for the patients' background factors, only the median size of resected metastases was different between patients with segmentectomies (median 18 mm, range 5-50 mm) and wedge resections (14 mm, 5-51 mm) ( P  < 0.001). Prolonged air leak developed more frequently in those undergoing segmentectomy compared with wedge resection (5.1% vs 1.8%) ( P  = 0.048). The resection-margin recurrence rate was higher in patients who underwent wedge resection compared with segmentectomy (7.3% vs 2.0%; P  = 0.035). The 5-year recurrence-free survival was 48.8% in patients with segmentectomy and 36.0% in patients with wedge resections. The 5-year overall survival was 80.1% in patients with segmentectomy and 68.5% in patients with wedge resection. Multivariable analysis revealed that the surgical procedure, segmentectomy, was a significant favourable factor for recurrence (hazard ratio: 0.63, 95% confidence interval: 0.44-0.87, P  = 0.005), but not for overall survival (hazard ratio: 0.65, 95% confidence interval: 0.38-1.05, P  = 0.080).

Conclusions

Segmentectomy demonstrated a good efficacy with less resection-margin recurrence in patients with resectable pulmonary-limited metastasis from colorectal cancer.

The role of neoadjuvant radiotherapy for locally-advanced rectal cancer with resectable synchronous metastasis

BACKGROUND

Although neoadjuvant radiotherapy is typically administered for locally-advanced rectal cancer to reduce local recurrence (LR), its role for patients who present with synchronous resectable liver and/or lung metastasis is not well defined. The aim of this study was to evaluate the role of neoadjuvant radiotherapy for patients with stage IV rectal cancer undergoing curative-intent surgery.

METHODS

This study is a retrospective review of a prospectively maintained surgical registry of all consecutive adult patients who underwent curative-intent resection at Mayo Clinic in Rochester, MN, from January 1990 until December 2014 with a median follow-up time of 43 (IQR 16-67) months. Eligible patients had locally-advanced rectal cancer (T3, T4 and/or nodal involvement) with synchronous resectable liver and/or lung metastasis. Exclusion criteria were as follows: patients with primary tumor stage of T1N0 or T2N0, patients with metastasis to organs other than the liver or lung, patients who had palliative resection, patients who had non-surgical treatment of synchronous metastasis (e.g., radiofrequency ablation), patients who received postoperative radiotherapy, or absence of research authorization. Ninety three patients were included of which 47 received neoadjuvant radiotherapy and 46 did not. All patients received neoadjuvant chemotherapy +/- radiotherapy followed by curative-intent surgery with metastasectomy performed either simultaneously with resection of the primary tumor or as a planned staged resection. The primary outcomes of this study are LR, distant metastasis, overall and disease-specific survival (DSS).

RESULTS

LR was observed in 12 patients (26%) who did not receive radiotherapy, while no LR developed in those who received neoadjuvant radiotherapy, P<0.001. Univariate analysis showed that neither age, sex, ASA class, BMI, tumor location, procedure performed, or neoadjuvant chemotherapy were associated with subsequent LR. The 5-year overall survival (OS) rates were: 43.3% (95% CI: 30.1, 62.3) for no radiotherapy vs. 58.3% (95% CI: 43.4, 78.2) with radiotherapy.

CONCLUSIONS

Neoadjuvant radiotherapy should be considered in patients with locally-advanced stage IV rectal cancer. These data add to the evidence supporting neoadjuvant radiotherapy in the setting of resectable metastatic disease.

Insurance Status and Hospital Payer Mix Are Linked With Variation in Metastatic Site Resection in Patients With Advanced Colorectal Cancers

BACKGROUND

Despite substantially improved survival with metastatic site resection in colorectal cancers, uptake of aggressive surgical approaches remains low among certain patients. It is unknown whether financial determinants of care, such as insurance status, play a role in this treatment gap.

OBJECTIVE

We sought to evaluate the effect of insurance status on metastasectomy in patients with advanced colorectal cancers.

DESIGN

This was a retrospective cohort study.

SETTINGS

Using the National Cancer Data Base Participant User File, incident cases of colorectal cancer metastatic to the lung and/or liver with diagnosis from 2010 to 2013 were identified.

PATIENTS

We identified 42,300 patients in our cohort with a mean age 64 years.

MAIN OUTCOME MEASURES

Controlling for patient, tumor, and hospital characteristics, hierarchical regression was used to examine associations between hospital payer mix and metastatic site resection. Metastatic site resection occurred in 12.3% of all patients.

RESULTS

Adjusting for patient and hospital fixed effects, we found that patients who were uninsured or on Medicaid were 38% less likely to undergo metastasectomy (OR = 0.62 (95% CI, 0.56-0.66)). Patients in hospitals with staff treating a high percentage of uninsured patients or patients with Medicaid were less likely to undergo metastasectomy, even after controlling for individual patient insurance status.

LIMITATIONS

The study was limited by its retrospective design and the granularity and accuracy of the National Cancer Data Base.

CONCLUSIONS

Differences in insurance status and hospital payer mix are associated with differences in rates of metastatic site resection in patients with colorectal cancer that is metastatic to the lung and/or liver. There is a need for improved access to metastatic site resection for individual patients who are uninsured or who have Medicaid insurance, as well as for all patients who seek care at hospitals treating a large proportion of patients who are uninsured or on Medicaid. Remedies for individual patients could include improved access to private insurance through employment or individual plans or improved reimbursement from Medicaid for this procedure. Strategies for patients at low-performing hospitals include selective referral to centers that perform mestastectomy more frequently when appropriate.

Lung Metastases Treated With Stereotactic Ablative Radiation Therapy in Oligometastatic Colorectal Cancer Patients: Outcomes and Prognostic Factors After Long-Term Follow-Up

BACKGROUND

We evaluated a series of oligometastatic colorectal cancer (CRC) patients treated with stereotactic ablative body radiotherapy (SABR) delivered in all active lung metastases.

PATIENTS AND METHODS

Forty-four patients with 69 lung metastases were treated with SABR. Eleven patients presented with other sites of metastases before stereotactic body radiotherapy (SBRT), even though they had controlled/cured systemic disease.

RESULTS

The median follow-up was 36 months. The median overall survival (OS) was 38 months and 2 years, 3-year OS rates were 67.7% and 50.8%, respectively. The median progression-free survival (PFS) was 10 months and 2 years, 3-year PFS rates were 20.3% and 16.2%, respectively. Local recurrence occurred in 16 patients (36%).The first site of failure was local only in 22%, distant only in 35%, and local and distant in 14% of the patients. The 1-year, 2-year, and 3-year local PFS (LPFS) were 68.8%, 60.2%, and 54.2%, respectively. No Grade ≥ 3 toxicities were recorded in the univariate analysis; multiple lung metastases and synchronous oligometastatic disease were significantly associated with worse PFS (P = .04, and P < .001, respectively) and worse metastases-free survival (MFS; P = .04, and P < .001, respectively). The type of response was identified as a significant prognostic factor for OS (P = .014), PFS (P = .006), and LPFS (P < .001). In multivariate analysis single lung metastases treated with SBRT was associated with better MFS (P = .015). Metachronous oligometastatic disease and type of response were associated with significantly better PFS.

CONCLUSION

Stereotactic body radiotherapy is a valid therapy in the treatment of lung metastases for oligometastatic CRC patients presenting long survival. The rate of local control remains lower compared with other primaries. Further prospective cohorts would better evaluate effective fractionation for patients with oligometastatic CRC.

[Surgery for pulmonary metastases from colorectal cancer: Predictive factors for survival]

INTRODUCTION

Colorectal cancer is the 3rd commonest cause of death from cancer: 5% of patients will develop lung metastases. The management of oligometastatic disease is based on the objective of optimal local control.

STATE OF THE ART

To date, no results from randomized control trials support the resection of pulmonary metastases in oligometastastic colorectal cancer patients. However, numerous series, mainly retrospective, report long-term survival for highly selected patients, with 5-year survival ranging from 45 to 65% in the most recent series. The consensual predictive factors of a good prognosis are: a disease free-interval>36 months, a number of metastases≤3, a normal level of carcino-embryonic antigen and the absence of hilar or mediastinal lymph node involvement.

PERSPECTIVES

Around 20 to 40% of patients will develop recurrence, probably linked to the presence of undetectable micrometastases. Therefore, experimental work is being undertaken to develop new treatment techniques such as isolated lung perfusion, radiofrequency ablation and stereotactic radiation therapy.

CONCLUSION

Highly selected patients suffering from colorectal cancer lung metastases could benefit from resection with improved survival and disease-control.

Anti-angiogenic agents in metastatic colorectal cancer

Colorectal cancer (CRC) is a major public health concern being the third leading cause of cancer mortality in the United States. The availability of better therapeutic options has led to a decline in cancer mortality in these patients. Surgical resection should be considered in all stages of the disease. The use of conversion therapy has made surgery a potentially curative option even in patients with initially unresectable metastatic disease. In this review we discuss the role of various anti-angiogenic agents in patients with metastatic CRC (mCRC). We describe the mechanism of action of these agents, and the rationale for their use in combination with chemotherapy. We also review important clinical studies that have evaluated the safety and efficacy of these agents in mCRC patients. Despite the discovery of several promising anti-angiogenic agents, mCRC remains an incurable disease with a median overall survival of just over 2 years in patients exposed to all available treatment regimens. Further insights into tumor biology and tumor microenvironment may help improve outcomes in these patients.