Factors causing early relapse after lung metastasis surgery

Results of redo pulmonary metastasectomy

Repeat surgical resection (redo) for pulmonary metastases is a questionable, albeit intriguing topic. We performed an extensive review of the literature, to specifically analyze results of redo pulmonary metastasectomies. We reviewed a total of 3,523 papers. Among these, 2,019 were excluded for redundancy and 1,105 because they were not completely retrievable. Out of 399 eligible papers, 183 had missing information or missing abstract, while 96 lacked data on survival. A total of 120 papers dated from 1991 onwards were finally included. Data regarding mortality, major morbidity, prognostic factors and long-term survivals of the first redo pulmonary metastasectomies were retrieved and analyzed. Homogeneity of data was affected by the lack of guidelines for redo pulmonary metastasectomy and the risks of bias when comparing different studies has to be considered. According to the histology sub-types, redo metastasectomies papers were grouped as: colorectal (n=42), sarcomas (n=36), others (n=20) and all histologies (n=22); the total number of patients was 3,015. Data about chemotherapy were reported in half of the papers, whereas targeted or immunotherapy in 9. None of these associated therapies, except chemotherapy in two records, did significantly modify outcomes. Disease-free interval before the redo procedure was the prevailing prognostic factor and nearly all papers showed a significant correlation between patients’ comorbidities and prognosis. No perioperative mortality was reported, while perioperative major morbidity was overall quite low. Where available, overall survival after the first redo metastasectomy ranged from 10 to 72 months, with a 5-years survival of approximately 50%. The site of first recurrence after the redo procedure was mainly lung. Despite the data retrievable from literature are heterogeneous and confounding, we can state that redo lung metastasectomy is worthwhile when the lesions are resectable and the perioperative risk is low. At present, there are no “non-surgical” therapeutic options to replace redo pulmonary metastasectomies.

Microwave Ablation in the Management of Colorectal Cancer Pulmonary Metastases

PURPOSE

To review outcomes following microwave ablation (MWA) of colorectal cancer pulmonary metastases and assess predictors of oncologic outcomes.

METHODS

Technical success, primary and secondary technique efficacy rates were evaluated for 50 patients with 90 colorectal cancer pulmonary metastases at immediate, 4-8 weeks post-MWA and subsequent follow-up CT and/or ¹⁸F-FDG PET/CT. Local tumor progression (LTP) rate, LTP-free survival (LTPFS), cancer-specific and overall survivals were assessed. Complications were recorded according to SIR classification.

RESULTS

Median follow-up was 25.6 months. Median tumor size was 1 cm (0.3-3.2 cm). Technical success, primary and secondary technique efficacy rates were 99, 90 and 92%, respectively. LTP rate was 10%. One-, 2- and 3-year LTPFS were: 93, 86 and 86%, respectively, with median LTPFS not reached. Median overall survival was 58.6 months, and median cancer-specific survival (CSS) was not reached. One-, 2- and 3-year overall and CSS were 94% and 98, 82 and 90%, 61 and 70%, respectively. On univariate analysis, minimal ablation margin (p < 0.001) and tumor size (p = 0.001) predicted LTPFS, with no LTP for minimal margin ≥ 5 mm and/or tumor size < 1 cm. Pleural-based metastases were associated with increased LTP risk (p = 0.002, SHR = 7.7). Pre-MWA CEA level > 10 ng/ml (p = 0.046) and ≥ 3 prior chemotherapy lines predicted decreased CSS (p = 0.02). There was no 90-day death. Major complications rate was 13%.

CONCLUSIONS

MWA with minimal ablation margin ≥ 5 mm is essential for local control of colorectal cancer pulmonary metastases. Pleural-based metastases and larger tumor size were associated with higher risk of LTP. CEA level and pre-MWA chemotherapy impacted CSS.

Thermal Ablation of Colorectal Lung Metastases: Retrospective Comparison Among Laser-Induced Thermotherapy, Radiofrequency Ablation, and Microwave Ablation

OBJECTIVE

The purpose of this study is to retrospectively evaluate local tumor control, time to tumor progression, and survival rates among patients with lung metastatic colorectal cancer who have undergone ablation therapy performed using laser-induced thermotherapy (LITT), radiofrequency ablation (RFA), or microwave ablation (MWA).

MATERIALS AND METHODS

Data for this retrospective study were collected from 231 CT-guided ablation sessions performed for 109 patients (71 men and 38 women; mean [± SD] age, 68.6 ± 11.2 years; range, 34-94 years) from May 2000 to May 2014. Twenty-one patients underwent LITT (31 ablations), 41 patients underwent RFA (75 ablations), and 47 patients underwent MWA (125 ablations). CT scans were acquired 24 hours after each therapy session and at follow-up visits occurring at 3, 6, 12, 18, and 24 months after ablation. Survival rates were calculated from the time of the first ablation session, with the use of Kaplan-Meier and log-rank tests. Changes in the volume of the ablated lesions were measured using the Kruskal-Wallis method.

RESULTS

Local tumor control was achieved in 17 of 25 lesions (68.0%) treated with LITT, 45 of 65 lesions (69.2%) treated with RFA, and 91 of 103 lesions (88.3%) treated with MWA. Statistically significant differences were noted when MWA was compared with LITT at 18 months after ablation (p = 0.01) and when MWA was compared with RFA at 6 months (p = 0.004) and 18 months (p = 0.01) after ablation. The overall median time to local tumor progression was 7.6 months. The median time to local tumor progression was 10.4 months for lesions treated with LITT, 7.2 months for lesions treated with RFA, and 7.5 months for lesions treated with MWA, with no statistically significant difference noted. New pulmonary metastases developed in 47.6% of patients treated with LITT, in 51.2% of patients treated with RFA, and in 53.2% of patients treated with MWA. According to the Kaplan-Meier test, median survival was 22.1 months for patients who underwent LITT, 24.2 months for those receiving RFA, and 32.8 months for those who underwent MWA. The overall survival rate at 1, 2, and 4 years was 95.2%, 47.6%, and 23.8%, respectively, for patients treated with LITT; 76.9%, 50.8%, and 8.0%, respectively, for patients treated with RFA; and 82.7%, 67.5%, and 16.6%, respectively, for patients treated with MWA. The log-rank test revealed no statistically significant difference among LITT, RFA, and MWA. The progression-free survival rate at 1, 2, 3, and 4 years was 96.8%, 52.7%, 24.0%, and 19.1%, respectively, for patients who underwent LITT; 77.3%, 50.2%, 30.8%, and 16.4%, respectively, for patients who underwent RFA; and 54.6%, 29.1%, 10.0%, and 1.0%, respectively, for patients who underwent MWA, with no statistically significant difference noted among the three ablation methods.

CONCLUSION

LITT, RFA, and MWA can be used as therapeutic options for lung metastases resulting from colorectal cancer. Statistically significant differences in local tumor control revealed a potential advantage in using MWA. No differences in time to tumor progression or survival rates were detected when the three different ablation methods were compared.

Local therapy with continued EGFR tyrosine kinase inhibitor therapy as a treatment strategy in EGFR-mutant advanced lung cancers that have developed acquired resistance to EGFR tyrosine kinase inhibitors

BACKGROUND

Development of acquired resistance limits the utility of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) for the treatment of EGFR-mutant lung cancers. There are no accepted targeted therapies for use after acquired resistance develops. Metastasectomy is used in other cancers to manage oligometastatic disease. We hypothesized that local therapy is associated with improved outcomes in patients with EGFR-mutant lung cancers with acquired resistance to EGFR TKI.

METHODS

Patients who received non-central nervous system local therapy were identified by a review of data from a prospective biopsy protocol for patients with EGFR-mutant lung cancers with acquired resistance to EGFR TKI therapy and other institutional biospecimen registry protocols.

RESULTS

Eighteen patients were identified, who received elective local therapy (surgical resection, radiofrequency ablation, or radiation). Local therapy was well tolerated, with 85% of patients restarting TKI therapy within 1 month of local therapy. The median time to progression after local therapy was 10 months (95% confidence interval [CI]: 2-27 months). The median time until a subsequent change in systemic therapy was 22 months (95% CI: 6-30 months). The median overall survival from local therapy was 41 months (95% CI: 26-not reached).

CONCLUSIONS

EGFR-mutant lung cancers with acquired resistance to EGFR TKI therapy are amenable to local therapy to treat oligometastatic disease when used in conjunction with continued EGFR inhibition. Local therapy followed by continued treatment with an EGFR TKI is well tolerated and associated with long PFS and OS. Further study in selected individuals in the context of other systemic options is required.

Prolonged overall survival after pulmonary metastasectomy in patients with breast cancer

BACKGROUND

We investigated whether overall survival (OS) in patients with primary breast cancer (BC) is prolonged by pulmonary metastasectomy and which prognostic criteria may facilitate the decision in favor of thoracic surgical intervention.

METHODS

We assessed the median OS of 81 women after resection of pulmonary primary BC metastases by means of Kaplan-Meier estimators. Statistical interferences regarding prognostic factors were based on univariate log-rank tests and multivariate Cox proportional hazards regression. Matched patients who had not undergone resection from the Munich Tumor Registry served as controls.

RESULTS

Between 1982 and 2007, 81 patients were recruited prospectively. In 81.5% of the patients R0 resection was achieved, which was associated with significantly longer median OS than occurred after R1 or R2 resection (103.4 months versus 23.6 months versus 20.2 months, respectively; p<0.001). Multivariate analysis revealed R0 resection, number (n≥2), size (≥3 cm), and estrogen receptor (ER) and/or progesterone receptor (PR) positivity of metastases as independent prognostic factors for long-term survival. Presence of metastases in mediastinal and hilar lymph nodes correlated with decreased survival only in the univariate analysis (32.1 versus 103.4 months; p=0.095). Matched pair analysis confirmed that pulmonary metastasectomy significantly improved survival.

CONCLUSIONS

OS in patients with isolated pulmonary primary BC metastasis is prolonged by metastasectomy. Patients with multiple pulmonary lesions or metastases with negative hormone receptor (HR) status are at greater risk of disease relapse and should be followed closely. Moreover, additive treatment tailored to the biological subtype defined by HR expression should be considered for this group.

Safety distance in the resection of colorectal lung metastases: a prospective evaluation of satellite tumor cells with immunohistochemistry

OBJECTIVE

After complete pulmonary metastasectomy of colorectal lung metastases, tumor recurrence at the site of former resection develops in some patients. Well-described risk factors for local recurrence in the lung include incomplete resection and aerogenous spread of floating cancer cell clusters. The aim of this study was to describe the distribution and frequency of satellite cancer cells or clusters in resected tissue to deduce recommendations for safety margins in the future.

METHODS

Seventeen colorectal metastases from 10 patients were processed. Evaluation for pattern of growth, satellite cancer cells, and inflammatory reaction at the surface of the metastases was performed on 102 sections with CDX2 and cytokeratin 20 stains. The distance between the surface of the nodule and the satellite cancer cell was measured for each satellite and statistically evaluated.

RESULTS

As a pattern of growth, interstitial spread, inflammatory reaction, and lymphangitic spread were observed in 41.2%, 35.3%, and 23.5%, respectively. A total of 205 satellite cancer cells were identified in 16 of 17 metastases with a mean distance to the nodule of 0.99 ± 0.85 mm (range, 0.06-6.43 mm). The percentages of satellite tumor cells that are likely to be found within 1.59 mm, 3.43 mm, and 7.4 mm around the nodule are 68.27%, 95.5%, and 99.73%, respectively.

CONCLUSIONS

Satellite tumor cells, a potential source for local recurrence, are found in a high number around colorectal lung metastases. As a standard of care, a safety distance of 3 mm for small metastases and 8 to 10 mm for larger metastases must be maintained around the lesion to prevent local recurrence.