Prognostic factors for patients in postoperative brain metastases from surgically resected non-small cell lung cancer

Complex situations in lung cancer: multifocal disease, oligoprogression and oligorecurrence

With the emergence of lung cancer screening programmes and newly detected localised and multifocal disease, novel treatment compounds and multimodal treatment approaches, the treatment landscape of non-small cell lung cancer is becoming increasingly complex. In parallel, in-depth molecular analyses and clonality studies are revealing more information about tumorigenesis, potential therapeutical targets and the origin of lesions. All can play an important role in cases with multifocal disease, oligoprogression and oligorecurrence. In multifocal disease, it is essential to understand the relatedness of separate lesions for treatment decisions, because this information distinguishes separate early-stage tumours from locally advanced or metastatic cancer. Clonality studies suggest that a majority of same-histology lesions represent multiple primary tumours. With the current standard of systemic treatment, oligoprogression after an initial treatment response is a common scenario. In this state of induced oligoprogressive disease, local ablative therapy by either surgery or radiotherapy is becoming increasingly important. Another scenario involves the emergence of a limited number of metastases after radical treatment of the primary tumour, referred to as oligorecurrence, for which the use of local ablative therapy holds promise in improving survival. Our review addresses these complex situations in lung cancer by discussing current evidence, knowledge gaps and treatment recommendations.

Examination of the effectiveness of local therapy for oligo-recurrence of EGFR-mutated NSCLC

BACKGROUND

The effectiveness of local therapy has been reported in patients with oligo-recurrence of non-small cell lung cancer (NSCLC), a metachronous recurrence with a limited number of recurrences, which can be treated with local therapy. Conversely, remarkable progress has been made in systemic therapy for NSCLC with the advent of molecular targeted therapy. In particular, epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) are very effective in the treatment of EGFR-mutated NSCLC. There is currently no consensus on treatment for oligo-recurrence of EGFR-mutated NSCLC.

METHODS

From 2004 to 2014, 811 patients underwent complete resection for NSCLC at Kitasato University Hospital and, of these, 244 patients developed recurrence. Oligo-recurrence was defined as the presence of two or less recurrent lesions, and 34 patients presented with EGFR-mutated oligo-recurrence.

RESULTS

We retrospectively examined and compared the effects of EGFR-TKIs with those of radical local therapy in patients with oligo-recurrent EGFR-mutated NSCLC. The five-year post-recurrence survival (PRS) rates of patients with EGFR-mutated oligo-recurrence who received radical local therapy (n = 23) and those who did not (n = 11) were 59.4 and 45.5%, respectively (p = 0.777). Multivariate analysis revealed no favorable prognostic factors associated with prolonged PRS, and radical local therapies did not improve PRS in patients with oligo-recurrence (p = 0.551).

CONCLUSION

Radical local therapy did not affect PRS in patients with oligo-recurrent EGFR-mutated NSCLC. Even in cases of oligo-recurrence, the administration of local therapy in patients with EGFR-mutated NSCLC might be carefully considered.

A Reasonable Definition of Oligo-Recurrence in Non-Small-Cell Lung Cancer

BACKGROUND

The concept of oligo-recurrence in non-small-cell lung cancer (NSCLC) has been suggested to describe the possibility of achieving long-term survival or even cure with local therapy for recurrence despite having recurrent disease. Oligo-recurrence involves a limited number of metachronous recurrences that can be treated with local therapy. However, the number of recurrences that constitutes an oligo-recurrence has varied among studies and remains to be defined. The aim of this study was to elucidate the number of recurrences that constitutes an oligo-recurrence in NSCLC.

PATIENTS AND METHODS

We retrospectively reviewed 577 patients with NSCLC who had underwent complete resection and developed recurrence between 1990 and 2009, and these patients were evaluated. Patients were categorized according to the number of recurrences, and postrecurrence survival (PRS) was compared between groups.

RESULTS

Altogether, 270 patients underwent local therapy for all recurrent lesions. In these patients, sex (female), histological type (adenocarcinoma), gene mutation status, recurrence-free interval <1 year, and presence of 1 or 2 recurrences were factors associated with prolonged PRS. Additionally, all patients who maintained a cancer-free status for at least 5 years after treatment for recurrence and were considered possibly cured, had 1 or 2 recurrences.

CONCLUSION

Among patients receiving radical local therapy, the PRS was particularly longer among those with 1 or 2 recurrences, and these patients were able to aim for postrecurrence cure. Thus, a reasonable threshold to define oligo-recurrence in NSCLC is 1 or 2 recurrences that can be treated with local therapy.

Comparison of local therapy in patients with lung oligo-recurrence of non-small-cell lung cancer

BACKGROUND AND OBJECTIVES

The effectiveness of local therapy has been reported in non-small-cell lung cancer (NSCLC) patients with oligo-recurrence. However, there is still no clear consensus on the choice of local therapy. We aimed to examine the choice of local therapy in NSCLC patients with lung oligo-recurrence.

METHODS

Among 1760 consecutive NSCLC patients who underwent complete resection between 1990 and 2008, 535 patients developed recurrence. Lung oligo-recurrence was defined as 1-5 metachronous recurrences limited to the lungs only; such recurrence was found in 97 patients. We examined the differences in the prognosis of each therapy for these patients.

RESULTS

The 5-year postrecurrence survival (PRS) rates in patients who underwent local therapy (n = 54) and those who did not (n = 43) were 55.6% and 31.1%, respectively; it was significantly higher in patients who underwent local therapy (p = 0.004). Among 47 patients who underwent resection or radiation therapy, the 5-year PRS rates were 61.5% and 47.6% (p = 0.258), and the 5-year postrecurrence progression-free survival rates were 30.3% and 24.7% (p = 0.665), respectively, without any significant difference.

CONCLUSIONS

Patients with lung oligo-recurrence should consider local therapy individually, depending on their general condition.

Characteristics of surgically resected non-small cell lung cancer patients with post-recurrence cure

Background

The prognosis of postoperative recurrence in patients with non‐small cell lung cancer (NSCLC) is poor. However, depending on the recurrence patterns and treatment options, some patients can achieve long‐term survival following recurrence. In this study, we investigated the clinicopathological characteristics of NSCLC patients with curable disease who developed postoperative recurrence.

Methods

This retrospective study enrolled 535 patients who had developed recurrence from among 1760 consecutive patients with NSCLC who underwent curative resection from 1990 to 2008.

Post‐recurrence cure was defined as being cancer‐free for at least five years after treatment for recurrence in patients who had undergone radical local treatment or chemotherapy. The clinicopathological characteristics associated with post‐recurrence cure were analyzed.

Results

Among 535 patients who developed recurrence, 24 (4.5%) achieved post‐recurrence cure. The median post‐recurrence follow‐up duration was 151 (85–275) months for those who achieved post‐recurrence cure. The solitary recurrent lesions and local treatment for the initial recurrence site were significantly more for patients who could be cured after they developed recurrence. All patients with post‐recurrence cure received only radical local treatment for the recurrent lesions.

Conclusions

Some patients with solitary recurrent NSCLC lesions can be cured with only radical local treatment.

Key points

Significant findings of the study

The post‐recurrence cure patients maintained a cancer‐free status for five years after treatment for recurrence without a second recurrence. All patients with post‐recurrence cure received only radical local treatment for recurrence and had significantly higher number of solitary recurrent lesions.

What this study adds

Some patients with solitary recurrent NSCLC lesions after resection can be cured with only radical local treatment.

Identification and validation of NOLC1 as a potential target for enhancing sensitivity in multidrug resistant non-small cell lung cancer cells

Adjuvant chemotherapy has become the frequently adopted standard therapeutic approach for non-small cell lung cancer (NSCLC). However, the development of multidrug resistance (MDR) is a major obstacle contributing to the failure of chemotherapy. This study aimed to identify genes associated with MDR development that predict tumor response to chemotherapy in NSCLC. In the present study, a multidrug-resistant NSCLC cell sub-line, A549/MDR, was established from the A549/DDP cell line and characterized. The resistance index (RI) of this subline was calculated according to the IC50 of A549/MDR relative to the parental A549/DDP cells. The gene expression profiles of A549/DDP and A549/MDR were obtained using an oligonucleotide microarray (Agilent SureHyb microarray chip). The microarray results were validated by qRT-PCR and selected genes were analyzed by in vitro loss-of-function experiments. Gene expression profiling identified 921 differentially expressed genes (DEGs) according to the selection criteria, in which 541 genes were upregulated and 380 genes were downregulated in A549/MDR compared with A549/DDP cells. We found that these DEGs are involved in diverse biological processes, including ribonucleoprotein complex, drug metabolism, the Hippo signaling pathway and transcriptional misregulation. NOLC1, as one of the identified DEGs, was confirmed to be overexpressed in A549/MDR cells and its knockdown significantly enhanced the drug sensitivity of A549/MDR cells in response to multidrug treatment. Furthermore, knockdown of NOLC1 downregulated the expression levels of drug resistance-associated molecules (LRP and MDR1) in A549/MDR cells. These findings provide a new and comprehensive expression profile of MDR in NSCLC cells. Identification and validation of NOLC1 might be a promising therapeutic strategy for the management of MDR of NSCLC patients.

Surgical management of oligometastatic non-small cell lung cancer

The oligometastatic stage IV non-small cell lung cancer (NSCLC) offers a new surgical opportunity. New reported data is showing that surgery can offer a reasonable benefit, in terms of long-term survival, to some patients. The advantages of surgical treatment rely on a more adequate patient selection and a better understanding of the biology of these tumors. Currently, mediastinal involvement of the primary tumor can be identified as the most important prognostic variable after curative-intent of synchronous or metachronous metastasis. It seems clear that the routine use of combined FDG-PET and CT will help to detect the more favorable cohort of oligometastatic patients. As expected, pathological T staging of the primary tumor and the completeness of its resection are also crucial factors influencing final results. The real benefit of the local treatment over synchronous or metachronous metastasis is controversial with series showing better outcomes for metachronous lesions than for synchronous and others offering equal results. Also non conclusive results appear when analyzing different sites of metastasis. Retrospective series tend to show different outcomes depending on the affected organ while usually no differences are found in prospective ones. Most of the current evidence is based on retrospective studies on patients collected along extended periods of time. That represents a great limitation to the knowledge on this topic. Some prospective analyses have added some insight, but still the quality of the evidence is too low to allow drawing robust conclusions. As frequently concluded, prospective well designed investigation is requested to ascertain the value of surgery in this specific population of patients with extended NSCLC.

Prognostic factors for cases with no extracranial metastasis in whom brain metastasis is detected after resection of non-small cell lung cancer

OBJECTIVES

This study aimed to determine prognostic factors associated with postrecurrence survival in cases with postoperative brain metastasis but with no extracranial metastasis in non-small cell lung cancer (NSCLC).

MATERIAL AND METHODS

Between 1992 and 2012, a total of 2832 patients underwent surgical resection for NSCLC. Among those, 86 patients had postoperative brain metastasis as the initial recurrence. Those patients were retrospectively reviewed.

RESULTS

The median follow-up time after the initial lung resection was 24.0 months (range, 2.0-126.0 months). The median overall survival after initial lung cancer resection was 25.0 months and the median overall postrecurrence survival was 11 months. An initial lesion of adenocarcinoma (hazard ratio, 0.548; 95% confidence interval, 0.318 to 0.946; p=0.031), non-pneumonectomy, and a disease-free interval longer than 10.0 months (hazard ratio, 0.565; 95% confidence interval, 0.321-0.995; p=0.048) from the initial lung resection to the diagnosis of brain metastasis positively related to a good postrecurrence survival. Solitary brain metastasis and a size of less than 3 cm for the largest brain lesion were also positive factors for postrecurrence survival. Systemic chemotherapy for brain metastasis (hazard ratio, 0.356; 95% confidence interval, 0.189-0.670; p=0.001) and local treatment of surgery and/or stereotactic radiosurgery (SRS) for brain lesions (hazard ratio, 0.321; 95% confidence interval, 0.138-0.747; p=0.008) were positive factors for better postrecurrence survival.

CONCLUSION

In patients with brain metastasis after resection for NSCLC with no extracranial metastasis, adenocarcinoma histologic type, longer disease-free interval, systemic chemotherapy for brain metastasis and local treatment of surgery and/or SRS for brain metastasis are independent positive prognostic factors for postrecurrence survival.

Prognostic factors in patients with postoperative brain recurrence from completely resected non-small cell lung cancer

Background

Treatment strategies for brain metastasis from lung cancer have been making progress. The aim of this retrospective analysis was to investigate the post-recurrent prognostic factors in patients with brain metastasis after complete resection of non-small cell lung cancer (NSCLC).

Methods

We retrospectively reviewed the medical records of 40 patients found to have postoperative brain metastasis from NSCLC in our institution from 2002 to 2008. All patients had undergone radical pulmonary resection for the lung cancer. The impact of numerous variables on survival were assessed, including gender, age, carcinoembryonic antigen (CEA), tumor size, N status, histological type, number of brain metastases, tumor size of brain metastasis, presence of symptoms from the brain tumor(s), and use of perioperative chemotherapy.

Results

The median follow-up was 20.6 months (range, 3.4–66 months). The five-year survival rate from the diagnosis of brain recurrence was 22.5%. In univariate analysis, the favorable prognostic factors after brain recurrence included a normal range of CEA, no extracranial metastasis, no symptoms from the brain metastasis, brain metastasis (less than 2 cm), and radical treatment (craniotomy or stereotactic radiosurgery [SRS]). The multivariate Cox model identified that a small brain metastasis and radical treatment were independent favorable prognostic factors.

Conclusions

This study found that the implementation of radical therapy for metastatic brain tumor(s) when the tumor is still small contributed to an increase in patients' life expectancy.