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.

Chemotherapy for pulmonary large cell neuroendocrine carcinomas: does the regimen matter?

Pulmonary large cell neuroendocrine carcinoma (LCNEC) is rare. Chemotherapy for metastatic LCNEC ranges from small cell lung carcinoma (SCLC) regimens to nonsmall cell lung carcinoma (NSCLC) chemotherapy regimens. We analysed outcomes of chemotherapy treatments for LCNEC.The Netherlands Cancer Registry and Netherlands Pathology Registry (PALGA) were searched for patients with stage IV chemotherapy-treated LCNEC (2003-2012). For 207 patients, histology slides were available for pathology panel review. First-line platinum-based combined chemotherapy was clustered as "NSCLC-t", comprising gemcitabine, docetaxel, paclitaxel or vinorelbine; "NSCLC-pt", with pemetrexed treatment only; and "SCLC-t", consisting of etoposide chemotherapy.A panel review diagnosis of LCNEC was established in 128 out of 207 patients. NSCLC-t chemotherapy was administered in 46% (n=60), NSCLC-pt in 16% (n=20) and SCLC-t in 38% (n=48) of the patients. The median (95% CI) overall survival for NSCLC-t chemotherapy was 8.5 (7.0-9.9) months, significantly longer than patients treated with NSCLC-pt, with a median survival of 5.9 (5.0-6.9) months (hazard ratio 2.51, 95% CI 1.39-4.52; p=0.002) and patients treated with SCLC-t chemotherapy, with a median survival of 6.7 (5.0-8.5) months (hazard ratio 1.66, 95% CI 1.08-2.56; p=0.020).In patients with LCNEC, NSCLC-t chemotherapy results in longer overall survival compared to NSCLC-pt and SCLC-t chemotherapy.

Clinical features of large cell neuroendocrine carcinoma: a population-based overview.

Pulmonary large cell neuroendocrine carcinoma (LCNEC) is an orphan disease and few data are available on its clinical characteristics. Therefore, we analysed LCNEC registered in the Netherlands Cancer Registry, and compared data with small cell lung carcinoma (SCLC), squamous cell carcinoma (SqCC) and adenocarcinoma (AdC).Histologically confirmed LCNEC (n=952), SCLC (n=11 844), SqCC (n=19 633) and AdC (n=24 253) cases were selected from the Netherlands Cancer Registry (2003-2012). Patient characteristics, metastasis at diagnosis (2006 or later), overall survival (OS) including multivariate Cox models and first-line treatment were compared for stage I-II, III and IV disease.The number of LCNEC cases increased from 56 patients in 2003 to 143 in 2012, accounting for 0.9% of all lung cancers. Stage IV LCNEC patients (n=383) commonly had metastasis in the liver (47%), bone (32%) and brain (23%), resembling SCLC. Median OS (95% CI) of stage I-II, III and IV LCNEC patients was 32.4 (22.0-42.9), 12.6 (10.3-15.0) and 4.0 (3.5-4.6) months, respectively. Multivariate-adjusted OS of LCNEC patients resembled that of SCLC patients, and was poorer than those of SqCC and AdC patients. However, frequency of surgical resection and adjuvant chemotherapy resembled SqCC and AdC more than SCLC.Diagnosis of LCNEC has increased in recent years. The metastatic pattern of LCNEC resembles SCLC as does the OS. However, early-stage treatment strategies seem more comparable to those of SqCC and AdC.

An International Registry Study of Early-Stage NSCLC treatment variations (LUCAEUROPE) in Europe and the USA highlighting variations.

OBJECTIVE: Harmonized European NSCLC incidence, treatment approach, and survival based on national tumor registries are unclear. SUMMARY BACKGROUND DATA: Surgery has the potential to cure NSCLC and significantly prolong survival. This large-scale international study aimed to investigate treatment variations in Europe and the USA, as well as the determinants for its utilization. METHODS: The retrospective cohort study analyzed data from six European national population-based cancer registries (Belgium, Denmark, Estonia, Germany, the Netherlands, and Slovenia) and the US SEER database from 2010-2015. RESULTS: The study computed cancer incidence, survival, and age-standardized proportions of the use of various therapies. Multivariable logistic regression models were used to assess associations between resection and demographic and clinical parameters. A total of 428,107 records were analyzed. Among all countries, Estonia had the highest surgical resection rate (79.3 %) and the lowest radiation rate (7.3 %) for stage I patients. The Netherlands had the highest rate of radiotherapy across all years of investigation and the lowest surgery rate between 2012 and 2015. The primary treatment for early-stage NSCLC showed significant international variation, with the USA having a decrease in surgical rates from 67.6 % to 59.5 %. Resection was less frequently performed as tumor stage increased, patients aged, other lung cancer besides adenocarcinoma was present, and when the tumor site overlapped multiple lobes. CONCLUSIONS: Resection rates have declined in some studied European countries and the USA and resection rates vary substantially among countries. Interpretation of current scientific lung cancer evidence and international guidelines results in wide variations in patient treatment.

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.

Disease relapse in relation to lymph node sampling in lung carcinoid patients.

The predictive value of the extent of peri-operative lymph node (LN) sampling in relation to disease relapse in patients with pulmonary carcinoid (PC) is unknown. Furthermore, post-surgery follow-up recommendations rely on institutional retrospective studies with short follow-ups. We aimed to address these shortcomings by examining the relation between LN sampling and relapse in a population-based cohort with long-term follow-up. By combining the Dutch nationwide pathology and cancer registries, all patients with surgically resected PC (2003-2012) were included in this analysis (last update 2020). The extent of surgical LN dissection was scored for the number of LN samples, location (hilar/mediastinal), and completeness of resection according to European Society of Thoracic Surgeons (ESTS) guidelines. Relapse-free interval (RFI) was evaluated using Kaplan Meier and multivariate regression analysis. 662 patients were included. The median follow-up was 87.5 months. Relapse occurred in 10% of patients, mostly liver (51.8%) and locoregional sites (45%). The median RFI was 48.1 months (95% CI 36.8-59.4). Poor prognostic factors were atypical carcinoid, pN1/2, and R1/R2 resection. In 546 patients LN dissection data could be retrieved; at least one N2 LN was examined in 44% and completeness according to ESTS in merely 7%. In 477 cN0 patients, 5.9% had pN1 and 2.5% had pN2 disease. In conclusion, relapse occurred in 10% of PC patients with a median RFI of 48.1 months thereby underscoring the necessity of long-term follow-up. Extended mediastinal LN sampling was rarely performed but systematic nodal evaluation is recommended as it provides prognostic information on distant relapse.

Real-World Acute Toxicity and 90-Day Mortality in Patients With Stage I NSCLC Treated With Stereotactic Body Radiotherapy.

INTRODUCTION: Stereotactic body radiotherapy (SBRT) has firmly established its role in stage I NSCLC. Clinical trial results may not fully apply to real-world scenarios. This study aimed to uncover the real-world incidence of acute toxicity and 90-day mortality in patients with SBRT-treated stage I NSCLC and develop prediction models for these outcomes. METHODS: Prospective data from the Dutch Lung Cancer Audit for Radiotherapy (DLCA-R) were collected nationally. Patients with stage I NSCLC (cT1-2aN0M0) treated with SBRT in 2017 to 2021 were included. Acute toxicity was assessed, defined as grade greater than or equal to 2 radiation pneumonitis or grade greater than or equal to 3 non-hematologic toxicity less than or equal to 90 days after SBRT. Prediction models for acute toxicity and 90-day mortality were developed and internally validated. RESULTS: Among 7279 patients, the mean age was 72.5 years, with 21.6% being above 80 years. Most were male (50.7%), had WHO scores 0 to 1 (73.3%), and had cT1a-b tumors (64.6%), predominantly in the upper lobes (65.2%). Acute toxicity was observed in 280 (3.8%) of patients and 90-day mortality in 122 (1.7%). Predictors for acute toxicity included WHO greater than or equal to 2, lower forced expiratory volume in 1 second and diffusion capacity for carbon monoxide, no pathology confirmation, middle or lower lobe tumor location, cT1c-cT2a stage, and higher mean lung dose (c-statistic 0.68). Male sex, WHO greater than or equal to 2, and acute toxicity predicted higher 90-day mortality (c-statistic 0.73). CONCLUSIONS: This nationwide study revealed a low rate of acute toxicity and an acceptable 90-day mortality rate in patients with SBRT-treated stage I NSCLC. Notably, advanced age did not increase acute toxicity or mortality risk. Our predictive models, with satisfactory performance, offer valuable tools for identifying high-risk patients.

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.

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.

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.

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.

The incidence and risk factors of metachronous colorectal cancer: an indication for follow-up.

BACKGROUND: Patients with colorectal cancer are at risk for developing metachronous colorectal cancer. The purpose of posttreatment surveillance is to detect and remove premalignant lesions to prevent metachronous colorectal cancer. OBJECTIVE: The aim of this study was to investigate the incidence of and predictive factors for metachronous colorectal cancer in patients with newly diagnosed colorectal cancer. DESIGN AND PATIENTS: The data on all patients with newly diagnosed colorectal cancer between 1995 and 2006 were obtained from the Rotterdam Cancer Registry in The Netherlands and studied for metachronous colorectal cancer. MAIN OUTCOME MEASURES: The annual incidence rate and the standardized incidence ratios were calculated. RESULTS: In total, colorectal cancer was diagnosed in 10,283 patients; there were 39,974 person-years of follow-up. The mean annual incidence rate of metachronous colorectal cancer was 314/100,000 person-years at risk during 10 years of follow-up, corresponding with a mean annual incidence of 0.3% and a cumulative incidence of 1.1% at 3 years, 2.0% at 6 years, and 3.1% at 10 years. The incidence of metachronous colorectal cancer after resection of a first colorectal cancer is significantly higher than the incidence of colorectal cancer in an age- and sex-matched general population (standardized incidence ratio 1.3, 95% CI 1.1-1.5). This difference is especially seen during the first 3 years after first colorectal cancer diagnosis (standardized incidence ratio 1.4, 95% CI 1.1-1.8). The presence of synchronous colorectal cancer was the only significant risk factor for developing metachronous colorectal cancer (relative risk 13.9, 95% CI 4.7-41.0). CONCLUSIONS: Despite the availability of colonoscopy, metachronous colorectal cancer is still seen during follow-up in patients with colorectal cancer; the highest risk is during the first 3 years after initial diagnosis. For this reason, a follow-up colonoscopy is useful at a short-term interval after colorectal cancer diagnosis. The presence of synchronous colorectal cancer at the time of first colorectal cancer diagnosis is the only predictive risk factor for developing metachronous colorectal cancer. Tailored surveillance programs may be considered in patients with a diagnosis of synchronous tumors.

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.

Surgery without preoperative histological confirmation of lung cancer: what is the current clinical practice?

BACKGROUND: There are discordances in the guidelines regarding the need to acquire histological diagnosis before surgical treatment of (presumed) lung cancer. Preoperative histological confirmation is always encouraged in this setting to prevent unnecessary surgery or when sublobar resection for small-sized tumors is considered. The aim of this retrospective cohort study was to assess the proportion of patients undergoing lung cancer resection in the Netherlands without preoperative pathological confirmation, based on the intraoperative pathological diagnosis (IOD) rate, and to determine characteristics that may influence IOD frequency. METHODS: Data on 10,226 patients, who underwent surgical treatment for lung cancer from 2010 to 2015, were retrieved from the Netherlands National Cancer Registry. We registered an IOD when the date of diagnosis equaled the date of the first surgical intervention. Tabulations and multivariable logistic regression were used to identify predictive parameters for IOD. RESULTS: 36% of surgical procedures were classified as IOD, and decreased with increasing tumor size and extent of surgery (57% for segmentectomy, 39% for lobectomy and 11% for pneumonectomy). IOD was more frequently observed in adenocarcinoma (41%), varied between hospitals from 13% to 66% and was less common when patients were referred from a hospital where thoracic surgery was not performed. Previous history of cancer did not affect IOD. CONCLUSIONS: More than one-third of patients with suspected lung cancer in the Netherlands was operated without preoperative histological confirmation. There was significant variation in IOD rates between different hospitals, which deserves further detailed analysis when striving for uniform surgical quality of care for patients with lung cancer.