Metformin use and lung cancer survival: a population-based study in Norway.

BACKGROUND: We assessed associations between metformin use and survival in a nationwide Norwegian cohort of lung cancer (LC) patients. METHODS: The study linked 22,324 LC patients from the Cancer Registry of Norway diagnosed 2005-2014 with the Norwegian Prescription Database. We estimated associations of pre- and post-diagnostic metformin use with overall survival (OS) and LC-specific survival (LCSS) using multivariable time-fixed and time-dependent Cox regression. RESULTS: Pre-diagnostic metformin use was not associated with improved survival in all patients. Nevertheless, pre-diagnostic metformin use was associated with better LCSS in squamous cell carcinoma (SCC) patients (hazard ratio (HR) = 0.79; 95% confidence interval (CI) 0.62-0.99) and in patients with regional stage SCC (HR = 0.67; 95%CI 0.47-0.95). Post-diagnostic metformin use was associated with improved LCSS in all patients (HR = 0.83; 95%CI 0.73-0.95), in patients with SCC (HR = 0.75; 95%CI 0.57-0.98), regional stage LC (HR = 0.74; 95%CI 0.59-0.94), and regional stage SCC (HR = 0.57; 95%CI 0.38-0.86). OS showed similar results. Analyses of cumulative use showed a dose-response relationship in all patients, patients with adenocarcinoma and SCC, and with regional and metastatic LC. CONCLUSIONS: Metformin use was associated with improved survival, especially LCSS in patients with regional stage SCC. Further prospective studies are required to clarify the role of metformin in LC treatment.

Results of neoadjuvant chemo(radio)therapy and resection for stage IIIA non-small cell lung cancer in The Netherlands.

Introduction: Concurrent chemoradiotherapy remains the main treatment strategy for patients with stage IIIA non-small cell lung cancer (NSCLC); stage cT3N1 or cT4N0-1 may be eligible for surgery and potentially resectable stage IIIA (N2) NSCLC for neoadjuvant therapy followed by resection. We evaluated treatment patterns and outcomes of patients with stage IIIA NSCLC in The Netherlands.Material and Methods: Primary treatment data of patients with clinically staged IIIA NSCLC between 2010 and 2016 were extracted from The Netherlands Cancer Registry. Patient characteristics were tabulated and 5-year overall survival (OS) was calculated and reported.Results: In total, 9,591 patients were diagnosed with stage IIIA NSCLC. Of these patients, 41.3% were treated with chemoradiotherapy, 11.6% by upfront surgery and 428 patients (4.5%) received neoadjuvant treatment followed by resection. The 5-year OS was 26% after chemoradiotherapy, 40% after upfront surgery and 54% after neoadjuvant treatment followed by resection. Clinical over staging was seen in 42.3% of the patients that were operated without neoadjuvant therapy.Conclusion: In The Netherlands, between 2010 and 2016, 4.5% of patients with stage IIIA NSCLC were selected for treatment with neoadjuvant therapy followed by resection. The 5-year OS in these patients exceeded 50%. However, the outcome might be overestimated due to clinical over staging.

Malignant Peritoneal Mesothelioma: Patterns of Care and Survival in the Netherlands: A Population-Based Study.

BACKGROUND: Malignant peritoneal mesothelioma (MPM) is a rare and aggressive disease. Recently, focus has shifted toward a more aggressive and multimodal treatment approach. This study aimed to assess the patterns of care and survival for MPM patients in the Netherlands on a nationwide basis. METHODS: The records of patients with a diagnosis of MPM from 1993 to 2016 were retrieved from the Dutch Cancer Registry. Data regarding diagnosis, staging, treatment, and survival were extracted. Cox regression analyses and Kaplan-Meier survival curves were used to study overall survival. RESULTS: Between 1993 and 2016, MPM was diagnosed for 566 patients. Overall, the prognosis was very poor (24% 1-year survival). The most common morphologic subtype was the epithelioid subtype (88%), followed by the biphasic (8%) and sarcomatoid (4%) subtypes. Surgical treatment has become more common in recent years, which most likely has resulted in improved survival rates. In this study, improved survival was independently associated with hyperthermic intraperitoneal chemotherapy (hazard ratio [HR], 0.33; 95% confidence interval [CI], 0.21-0.55) and surgery with adjuvant systemic chemotherapy (HR, 0.33; 95% CI, 0.23-0.48). Nonetheless, most patients (67%) do not receive any form of anti-cancer treatment. CONCLUSION: This study indicated that MPM still is a rare and fatal disease. The survival rates in the Netherlands have improved slightly in the past decade, most likely due to more aggressive treatment approaches and increased use of surgery. However, most patients still do not receive cancer-directed treatment. To improve MPM management, and ultimately survival, care should be centralized in expert medical centers.

Is the sum of positive neuroendocrine immunohistochemical stains useful for diagnosis of large cell neuroendocrine carcinoma (LCNEC) on biopsy specimens?

AIMS: Pulmonary large cell neuroendocrine carcinoma (LCNEC) is underdiagnosed on biopsy specimens. We evaluated if routine neuroendocrine immunohistochemical (IHC) stains are helpful in the diagnosis of LCNEC on biopsy specimens. METHODS AND RESULTS: Using the Dutch pathology registry (PALGA), surgically resected LCNEC with matching pre-operative biopsy specimens were identified and haematoxylin and IHC slides (CD56, chromogranin-A, synaptophysin) requested. Subsequently, three pathologists assigned (1) the presence or absence of the WHO 2015 criteria and (2) cumulative size of all (biopsy) specimens. For validation, a tissue microarray (TMA) of non-small-cell lung cancer (NSCLC) (n = 77) and LCNEC (n = 19) was used. LCNEC was confirmed on the resection specimens in 32 of 48 re-reviewed cases. In 47% (n = 15 of 32) LCNEC was also confirmed in the paired biopsy specimens. Neuroendocrine morphology was absent in 53% (n = 17 of 32) of paired biopsy specimens, more often when smaller amounts of tissue were available for evaluation [29% < 5 mm (n = 14) versus 67% ≥5 mm (n = 18) P = 0.04]. Combined with current WHO criteria, positive staining for greater than or equal to two of three neuroendocrine IHC markers increased the sensitivity for LCNEC from 47% to 93% on paired biopsy specimens, and further validated using an independent TMA of LCNEC and NSCLC with sensitivity and specificity of 80% and 99%, respectively. CONCLUSIONS: LCNEC is difficult to diagnose because neuroendocrine morphology is frequently absent in biopsy specimens. In NSCLC devoid of obvious morphological squamous or adenocarcinoma features, positive staining in greater than or equal to two of three neuroendocrine IHC stains supports the diagnosis of LCNEC.

Pentameric last-digit preference and stage border avoidance in pathology measurement.

AIMS: Cancer treatment relies on accurate staging, an essential aspect of which is determination of the size of a tumour. Measuring the size of a tumour in daily practice often proves problematic and results in rounding of values to approximate values. It has been shown that size values are most frequently reported with end digits of 0 or 5. METHODS AND RESULTS: We sought to determine whether this observation holds true in our national cancer registry of breast and lung tumours. Data from patients with breast and lung cancer were retrieved from the Netherlands National Cancer Registry and analysed for tumour size. Whereas a preference for terminal digits of 0 or 5 (pentameric preference) was clearly present for lung cancer, critical pentameric values at stage boundaries were avoided in breast cancer. CONCLUSIONS: In conclusion, pathologists adopt a practical approach to tumour size measurement by rounding values and avoiding stage border boundary values, thus circumventing potential difficulties in treatment decisions.

Challenges and controversies in resectable non-small cell lung cancer: a clinician's perspective.

The treatment landscape of resectable early-stage non-small cell lung cancer (NSCLC) is transforming due to the approval of novel adjuvant and neoadjuvant systemic treatments. The European Medicines Agency (EMA) recently approved adjuvant osimertinib, adjuvant atezolizumab, adjuvant pembrolizumab, and neoadjuvant nivolumab combined with chemotherapy, and the approval of other agents or new indications may follow soon. Despite encouraging results, many unaddressed questions remain. Moreover, the transformed treatment paradigm in resectable NSCLC can pose major challenges to healthcare systems and magnify existing disparities in care as differences in reimbursement may vary across different European countries. This Viewpoint discusses the challenges and controversies in resectable early-stage NSCLC and how existing inequalities in access to these treatments could be addressed.

Adherence to national guidelines for gastric cancer in the Netherlands: a retrospective population-based audit.

In May 2009, a new clinical practice guideline for gastric cancer was released in the Netherlands. To determine the impact of this guideline, we evaluated trends in patterns of care, thereby focusing on the use of perioperative chemotherapy, the adequacy of lymphadenectomy and the proportion of non-curative resections. For our evaluation, we retrospectively collected information from the Netherlands Cancer Registry on 2,511 patients diagnosed with primary adenocarcinoma of the stomach during the period July 2008-June 2010, excluding tumors of the cardia. After comparing clinical management for patients diagnosed from July 2008 to June 2009 with that for patients diagnosed from July 2009 to June 2010, we conclude that our indicators for guideline adherence did not show major change, except for the proportion of patients that received an adequate lymphadenectomy (examination of ≥10 lymph nodes), which increased from 49% to 58% (p = 0.005), this increase being more pronounced for high-volume hospitals (p = 0.006). Preoperative chemotherapy was given in 45% of patients and 25% of resections was non-curative. For the total study population, the resection rate was 41% and 30-day mortality was 5.7%. However, this measure may underestimate the real operative risk for gastric cancer patients given supplementary information on postdischarge death and prolonged hospital stay.

Real-world treatment patterns and survival of patients with ROS1 rearranged stage IV non-squamous NSCLC in the Netherlands.

INTRODUCTION: Rearrangement of c-ros oncogene 1 (ROS1) is a rare gene alteration in patients with stage IV non-squamous non-small cell lung cancer (NSCLC). Molecular testing for ROS1 is recommended to enable primary treatment with tyrosine kinase inhibitors (TKI). Aim of this study was to describe real-world treatment patterns and survival for patients with ROS1 in the Netherlands. METHODS: All non-squamous NSCLC stage IV patients, diagnosed 2015-2019, were identified from the population-based Netherlands Cancer Registry (N = 19,871). For patients with ROS1 rearrangements (ROS1+ ) who received first line TKI, additional information about progression and second-line treatment was retrieved by active follow-up. Overall survival (OS) and progression-free survival (PFS) were calculated using Kaplan-Meier estimators. RESULTS: A total of 67 patients (0.43%) were diagnosed with a ROS1+ NSCLC. Systemic treatment was administered in 75% which was most often TKI (n = 34) followed by chemotherapy (n = 14). Two-year OS for patients receiving upfront TKI versus other systemic treatment was 53% (95% CI 35-68) and 50% (95% CI 25-71), respectively. For patients receiving TKI, median OS was 24.3 months. Survival was inferior in case of brain metastasis (BM) at diagnosis (5.2 months). One in five patients receiving TKI as a first line treatment had BM at diagnosis, of the remaining 22 another 9 developed BM during follow up. PFS was also inferior for patients with BM at diagnosis with a median PFS of 4.3 months versus 9.0 without BM. CONCLUSION: In this real-world population of ROS1+ NSCLC patients, only half received primary treatment with TKI. Overall survival and PFS during TKI were disappointing, mainly related to brain metastasis. TKI treatment with agents that have intra-cranial activity may be beneficial in this patient population and our results confirm the importance of performing an MRI of the brain as part of the standard diagnostic work up in patients with ROS1+ NSCLC.

Prognostic Implication of KRAS G12C Mutation in a Real-World KRAS-Mutated Stage IV NSCLC Cohort Treated With Immunotherapy in The Netherlands.

Introduction: With the approval of G12C inhibitors as the second line of treatment for KRAS G12C-mutated NSCLC, and the expanding research regarding targeting KRAS, it is key to understand the prognostic implication of KRAS G12C in the current first line of treatment. We compared overall survival (OS) of patients with stage IV KRAS G12C-mutated NSCLC to those with a KRAS non-G12C mutation in a first-line setting of (chemo)immunotherapy. Methods: This nationwide population-based study used real-world data from The Netherlands Cancer Registry. We selected patients with stage IV KRAS-mutated lung adenocarcinoma diagnosed in 2019 to 2020 who received first-line (chemo-)immunotherapy. Primary outcome was OS. Results: From 28,120 registered patients with lung cancer, 1185 were selected with a KRAS mutation, of which 494 had a KRAS G12C mutation. Median OS was 15.5 months (95% confidence interval [CI]: 13.6-18.4) for KRAS G12C versus 14.0 months (95% CI:11.2-15.7) for KRAS non-G12C (p = 0.67). In multivariable analysis, KRAS subtype was not associated with OS (hazard ratio = 0.95, 95% CI: 0.82-1.10). For the subgroup with programmed death-ligand 1 at 0% to 49% who received chemoimmunotherapy, median OS was 13.3 months (95% CI: 10.5-15.2) for G12C and 9.8 months (95% CI: 8.6-11.3) for non-G12C (p = 0.48). For the subgroup with programmed death-ligand 1 more than or equal to 50% who received monoimmunotherapy, the median OS was 22.0 months (95% CI: 18.4-27.3) for G12C and 18.9 months (95% CI: 14.9-25.2) for non-G12C (p = 0.36). Conclusions: There was no influence of KRAS subtype (G12C versus non-G12C) on OS in patients with KRAS-mutated stage IV NSCLC treated with first-line (chemo)immunotherapy.

Overall survival in advanced epidermal growth factor receptor mutated non-small cell lung cancer using different tyrosine kinase inhibitors in The Netherlands: a retrospective, nationwide registry study.

Background: Clinical guidelines advise osimertinib as preferred first line treatment for advanced epidermal growth factor receptor (EGFR) mutated non-small cell lung cancer (NSCLC) with deletions in exon 19 (del19) or exon 21 L858R mutation. However, for first-line osimertinib the real world overall survival (OS) in mutation subgroups remains unknown. Therefore, the aim of this study was to evaluate the real-world OS of those patients treated with different generations of EGFR-tyrosine kinase inhibitors (TKI), and to identify predictors of survival. Methods: Using real-world data from the Netherlands Cancer Registry (NCR) we assessed patients diagnosed with stage IV NSCLC with del19 or L858R mutation between January 1, 2015, and December 31, 2020, primarily treated with then regularly available TKIs (including osimertinib). Findings: Between January 1, 2015, and December 31, 2020, 57,592 patients were included in the NCR. Within this cohort we identified 1109 patients, 654 (59%) with del19 and 455 (41%) with L858R mutations, respectively; 230 (21%) patients were diagnosed with baseline brain metastases (BM). Patients were treated with gefitinib (19%, 213/1109), erlotinib (42%, 470/1109), afatinib (15%, 161/1109) or osimertinib (24%, 265/1109). Median OS was superior for del19 versus L858R (28.4 months (95% CI 25.6-30.6) versus 17.7 months (95% CI 16.1-19.5), p < 0.001. In multivariable analysis, no difference in survival was observed between various TKIs in both groups. Only in the subgroup of patients with del19 and baseline BM, a benefit was observed for treatment with osimertinib. Interpretation: In this nationwide real-world cohort, survival of Dutch patients with advanced NSCLC and an EGFR del19 mutation was superior versus those harboring an L858R mutation. Osimertinib performed only better as first-line treatment in patients with del19 and BM. Funding: None.

Survival of patients with KRAS G12C mutated stage IV non-small cell lung cancer with and without brain metastases treated with immune checkpoint inhibitors.

INTRODUCTION: Few data is available on whether brain metastases (BM) influence survival in patients with stage IV KRAS G12C mutated (KRAS G12C+ ) non-small cell lung cancer (NSCLC) treated with first-line immune checkpoint inhibitor (ICI) +/- chemotherapy ([chemo]-ICI). METHODS: Data was retrospectively collected from the population-based Netherlands Cancer Registry. The cumulative incidence of intracranial progression, overall survival (OS) and progression free survival (PFS) was determined for patients with KRAS G12C+ stage IV NSCLC diagnosed January 1 - June 30, 2019, treated with first-line (chemo)-ICI. OS and PFS were estimated using Kaplan-Meier methods and BM+ and BM- groups were compared using log-rank tests. RESULTS: Of 2489 patients with stage IV NSCLC, 153 patients had KRAS G12C+ and received first-line (chemo)-ICI. Of those patients, 35% (54/153) underwent brain imaging (CT and/or MRI), of which 85% (46/54) MRI. Half of the patients with brain imaging (56%; 30/54) had BM, concerning one-fifth (20%; 30/153) of all patients, of which 67% was symptomatic. Compared to BM-, patients with BM+ were younger and had more organs affected with metastasis. Around one-third (30%) of patients with BM+ had ≥5 BM at diagnosis. Three quarters of patients with BM+ received cranial radiotherapy prior to start of (chemo)-ICI. The 1-year cumulative incidence of intracranial progression was 33% for patients with known baseline BM and 7% for those without (p = 0.0001). Median PFS was 6.6 (95% CI 3.0-15.9) and 6.7 (95% CI 5.1-8.5) months for BM+ and BM- (p = 0.80), respectively. Median OS was 15.7 (95% CI 6.2-27.3) and 17.8 (95% CI 13.4-22.0) months for BM+ and BM- (p = 0.77), respectively. CONCLUSION: Baseline BM are common in patients with metastatic KRAS G12C+ NSCLC. During (chemo)-ICI treatment, intracranial progression was more frequent in patients with known baseline BM, justifying regular imaging during treatment. In our study, presence of known baseline BM did not influence OS or PFS.

Population-based survival for malignant mesothelioma after introduction of novel chemotherapy.

Malignant mesothelioma is known for its dismal prognosis and poor response to conventional treatment. Chemotherapy with cisplatin-antifolate combinations recently showed promising response rates and prolonged survival in randomised trials. To assess the impact of this development on clinical practice and survival at a population-based level, treatment patterns and survival trends were studied for patients diagnosed with mesothelioma in the period 1995-2006. 4,731 records were retrieved from the Netherlands Cancer Registry and chemotherapy use and median survival were analysed. For the periods 1995-1998 to 2005-2006, chemotherapy use increased from 8% to 36%. Median survival increased over time from 7.1 months to 9.2 months. For pleural mesothelioma, multivariable analysis demonstrated that survival was poorer for elderly patients and sarcomatoid tumours. The prognostic impact of chemotherapy increased with time. Median survival for chemotherapy treated patients improved from 10.1 months (1995-1998) to 13.1 months (2005-2006). For peritoneal mesothelioma, median survival was poor (3.9 months) but better for females and younger patients. This study demonstrates that chemotherapy use increased at a national level and coincided with an improvement in survival. The novel chemotherapy regimen appears to be more effective but, due to the observational nature of this study, alternative explanations cannot be excluded.

Mutation-tailored treatment selection in non-small cell lung cancer patients in daily clinical practice.

OBJECTIVES: The number of targeted drugs in non-small cell lung cancer (NSCLC) is ever-expanding and requires testing of an increasing number of predictive biomarkers. We present a comprehensive real-world evaluation of molecular testing and treatment selection in stage IV NSCLC patients in the Netherlands from 2017 to 2019. MATERIALS AND METHODS: Molecular pathology reports of NSCLC patients were collected from the Dutch Pathology Registry in time intervals between Oct-2017 and April-2019 (N = 5,038 patients) to study diagnostic yield. Linkage between the Dutch Pathology Registry and the Netherlands Cancer Registry enabled studying molecular testing rates for stage IV NSCLC initially diagnosed in 2017-Q4 (N = 1,193) and application of targeted therapy in stage IV NSCLC patients with potentially druggable alterations reported between Oct-2017 and June-2018 (N = 401). RESULTS: Predictive molecular testing was performed in 85.0% of adenocarcinomas, 60.4% of NSCLC-not otherwise specified (NOS) and 17.4% of squamous cell carcinomas. Testing rates were highest for EGFR and ALK (adenocarcinoma: 82.7% and 80.7%, respectively). Incidence of molecular driver alterations (i.e. EGFR, KRAS, ALK, ROS1, BRAF, MET, ERBB2, FGFR1) was 61.1% for adenocarcinomas, 42.3% for NSCLC-NOS, and 24.7% for squamous cell carcinomas. Therapeutically relevant alterations were detected at a higher frequency by NGS- versus non-NGS-approaches (adenocarcinoma: 62.4% versus 56.5%, respectively (P = 0.004)) due to a lower failure rate, more comprehensive testing and higher sensitivity. Uptake of treatment with a registered targeted therapy in eligible patients varied per actionable target, i.e. EGFR: 85.8%, ALK: 74.7%, ROS1: 33.7%, BRAF: 51.5%. Treatment with agents in clinical studies/compassionate use was lower, i.e. MET: 22.8%, HER2: 18.9%, RET: 6.7%. CONCLUSION: Real-world data show NGS-based approaches to be superior to non-NGS. Uptake of molecular testing and the corresponding targeted treatments was less than expected based on guidelines and even more so for trials, off-label use and compassionate use, indicating less than optimal access to rational treatment options.

Age-related treatment patterns for stage I NSCLC in three European countries.

INTRODUCTION: Surgery is the preferred treatment for patients with early-stage non-small cell lung cancer (NSCLC) while stereotactic body radiation therapy (SBRT) may be applied in patients with major comorbidity or high age. We evaluated the association between age and treatment utilization for early-stage NSCLC in patients diagnosed in 2015-2016 in three European countries. PATIENTS AND METHODS: Information was retrieved from population-based registries in England, Norway and the Netherlands. Treatment patterns and two-year overall survival rates for 105,124 patients with clinical stage I were analysed by age-group. RESULTS: Surgical resection rates were higher in Norway (55%) and England (53%) than in the Netherlands (47%), and decreased with increasing age. SBRT use was highest in the Netherlands (41%), followed by Norway (29%) and England (12%). In the Netherlands, SBRT was the prevailing treatment in patients aged 70 years or older. In octogenarians, the proportion not receiving curative intent treatment was 53% in England, versus 35% in Norway and 22% in the Netherlands. Two-year survival rates were better for surgery than for SBRT and slightly better in Norway. CONCLUSION: In patients aged 70 years or older, the proportion not receiving any curative treatment remains substantial, and differs significantly between countries. Measures to address these disparities are needed.

Risk of second primary malignancies among patients with carcinoid of the lung.

OBJECTIVES: Little is known about the etiology of pulmonary carcinoids (PC). Associations with other types of cancer may identify shared risk factors but results from earlier studies were inconclusive. The aim of the present study was to explore the association between PC and other primary malignancies for identifying risk factors. METHODS: A query of the nationwide Netherlands Cancer Registry generated data about patients diagnosed with PC from 1989 to 2018. The occurrence of second primary malignancies was evaluated separately for year 1 and years 2-30. The expected numbers of second primary malignancies were calculated using incidence reference tables, controlling for age, gender and period. Confidence intervals (95 % CI) for the ratio between observed and expected numbers (SIR: standardized incidence ratio) were calculated using Poisson distributions. RESULTS: In a total of 2933 patients with PC, 425 consecutive primary malignancies were observed in 376 patients. Concomitant diagnoses in the first year mainly comprised lung (n = 59) and renal cancer (n = 14). Metachronous malignancies beyond the first year were most common for breast (n = 50), colorectal (n = 41), prostate (n = 32), and lung cancer (n = 29). Beyond year 1, the overall risk of second primary cancer in patients with PC was similar to the risk within the general population (n = 256, SIR = 1.12, 95 % CI 0.99-1.27). Increased risks were observed for soft tissue sarcoma (n = 5, SIR = 3.52, 95 % CI 1.14-8.22) and GEPNET (n = 4, SIR = 4.30, 95 % CI 1.17-11.01). CONCLUSIONS: Concomitant diagnosis of PC with other cancers is common, reflecting surveillance diagnostics. Apart from MEN-1 family history, no shared risk factors could be identified.

Stage I non-small cell lung cancer: Treatment modalities, Dutch daily practice and future perspectives.

OBJECTIVES: Several treatment modalities are available for patients with stage I non-small cell lung cancer (NSCLC). Over the past decade, these treatment modalities have been further investigated and might have changed current treatment regimens. In this review we present an overview of the treatment options, developments and future perspectives for stage I NSCLC. Furthermore, we describe the current use of these treatment modalities in the Netherlands. MATERIALS AND METHODS: A bibliographical search was performed in PubMed and the Cochrane Library for publications concerning treatment modalities for stage I NSCLC. In addition, evidence-based guidelines of the European Society for Medical Oncology (ESMO) and the National Comprehensive Cancer Network (NCCN) were studied. RESULTS: The guideline-recommended treatment for operable stage I NSCLC patients is a lobectomy with systematic lymph node dissection. Inoperable patients or those refusing surgery are offered stereotactic ablative radiotherapy (SABR). Percutaneous ablation, such as radiofrequency ablation, is a non-surgical minimally invasive technique offered to those who are ineligible for surgery or SABR. The role of systemic therapy is currently limited. However, the efficacy of immunotherapy is being investigated in clinical trials. In the Netherlands, an increasing use of SABR and a relative decrease in resection rates have been observed. CONCLUSION: Surgery and SABR are currently the prevailing treatment modalities for stage I NSCLC patients. Despite optimization of treatment regimens, survival of patients with stage I NSCLC remains to be improved. Future studies are required to optimize treatment strategies, but also to investigate factors influencing treatment decision-making for patients with stage I NSCLC.

A Nationwide Study on the Impact of Routine Testing for EGFR Mutations in Advanced NSCLC Reveals Distinct Survival Patterns Based on EGFR Mutation Subclasses.

EGFR mutation analysis in non-small-cell lung cancer (NSCLC) patients is currently standard-of-care. We determined the uptake of EGFR testing, test results and survival of EGFR-mutant NSCLC patients in the Netherlands, with the overall objective to characterize the landscape of clinically actionable EGFR mutations and determine the role and clinical relevance of uncommon and composite EGFR mutations. Non-squamous NSCLC patients diagnosed in 2013, 2015 and 2017 were identified in the Netherlands Cancer Registry (NCR) and matched to the Dutch Pathology Registry (PALGA). Overall, 10,254 patients were included. Between 2013-2017, the uptake of EGFR testing gradually increased from 72.7% to 80.9% (p < 0.001). Multi-gene testing via next-generation sequencing (increased from 7.8% to 78.7% (p < 0.001), but did not affect the number of detected EGFR mutations (n = 925; 11.7%; 95% confidence interval (CI), 11.0-12.4) nor the distribution of variants. For patients treated with first-line EGFR inhibitors (n = 651), exon 19 deletions were associated with longer OS than L858R (HR 1.58; 95% CI, 1.30-1.92; p < 0.001) or uncommon, actionable variants (HR 2.13; 95% CI, 1.60-2.84; p < 0.001). Interestingly, OS for patients with L858R was similar to those with uncommon, actionable variants (HR 1.31; 95% CI, 0.98-1.75; p = 0.069). Our analysis indicates that grouping exon 19 deletions and L858R into one class of 'common' EGFR mutations in a clinical trial may mask the true activity of an EGFR inhibitor towards specific mutations.

Nationwide Real-world Cohort Study of First-line Tyrosine Kinase Inhibitor Treatment in Epidermal Growth Factor Receptor-mutated Non-small-cell Lung Cancer.

BACKGROUND: Only a few randomized trials directly compared the relative efficacy of tyrosine kinase inhibitors (TKIs) in patients with advanced epidermal growth factor receptor (EGFR)-mutated non-small-cell lung cancer (NSCLC), and most trials comprised selected series from Asian populations. Therefore, the aim of this study was to assess the overall survival (OS) of advanced EGFR-mutated NSCLC in a large white population and to evaluate variation between different TKIs and identify predictors of survival. PATIENTS AND METHODS: Information about clinical characteristics, treatment, and survival for 873 patients with stage IV EGFR + NSCLC, diagnosed from 2015 through 2017, was derived from the Netherlands Cancer Registry. OS was evaluated by actuarial analysis and multivariable Cox regression. Prognostic factors are reported as hazard ratios and 95% confidence intervals. RESULTS: A total of 596 (68%) patients received first-line treatment with regular TKIs, providing a median survival of 20.2 months. Forty-five percent of patients were 70 years and older, and 54% of patients had distant metastasis in multiple organs. In the multivariate analysis, survival was significantly worse for men, and patients with higher age, poorer performance, and ≥ 3 organs with metastasis. Compared with erlotinib, OS was worse for gefitinib users (adjusted hazard ratio, 1.30; 95% confidence interval, 1.02-1.64), predominantly in patients with brain metastasis. CONCLUSION: Dutch patients with EGFR-mutated NSCLC who received first-line treatment with regular TKIs have a median OS of 20.2 months in a nationwide real-world cohort. In patients with brain metastasis, erlotinib showed superior results compared with gefitinib and was similar to afatinib.

Postoperative mortality after primary cytoreductive surgery for advanced stage epithelial ovarian cancer: a systematic review.

OBJECTIVE: Accurate estimation of the risk of postoperative mortality (POM) is essential for the decision whether or not to perform cytoreductive surgery in a patient with advanced stage ovarian cancer. To ascertain modern reference figures, a systematic review of studies reporting POM after primary cytoreductive surgery for advanced stage epithelial ovarian cancer (EOC) was performed. MATERIALS AND METHODS: A Medline search was performed to retrieve papers on primary cytoreductive surgery for advanced stage EOC. Twenty-three papers met the inclusion criteria and were reviewed. RESULTS: According to population-based studies, POM after primary cytoreductive surgery for EOC is 3.7% on average. Single centre studies report an average rate of 2.5%. The overall mean POM is 2.8%. POM is more frequent for elderly women and after extensive procedures. Accurate information on age-specific and procedure-specific rates could not be obtained. CONCLUSION: POM rates after surgery for EOC are satisfactorily low. There is a clear need for reliable reference figures for mortality after debulking surgery in the elderly.

Underutilization of microsatellite instability analysis in colorectal cancer patients at high risk for Lynch syndrome.

OBJECTIVE: The revised Bethesda Guidelines were published to improve the efficiency of recognizing Lynch syndrome (LS) by identifying LS-related malignancies that should be analyzed for microsatellite instability (MSI). The aim of this study was to evaluate whether MSI analysis was performed in colorectal cancer patients at risk for LS according to the revised Bethesda Guidelines. MATERIAL AND METHODS: Patients diagnosed with colorectal cancer in 11 Dutch hospitals in 2005 and 2006 were selected from a regional database. The patients were included in the study if they met any of the following criteria; 1) diagnosed with colorectal cancer <50 years, 2) a second LS-associated tumor prior to the diagnosis of colorectal cancer in 2005/2006, and 3) colorectal cancer <60 years with a tumor displaying mucinous or signet-ring differentiation or medullary growth pattern. RESULTS: Of 1905 colorectal cancer patients, 169 met at least one of the inclusion criteria. MSI analysis had been performed in 23 (14%) of the 169 tumors. MSI status had been determined in 18 of 80 included patients aged <50 years, in 4 of 70 patients with a second LS-related tumor, and in 3 of 41 patients aged <60 years with high-risk pathology features. CONCLUSIONS: There is marked underutilization of MSI analysis in patients at risk for LS. As a result LS might be underdiagnosed both in patients with colorectal cancer and in their relatives.