Trends in epidemiology and primary treatment of anal squamous cell carcinoma in the Netherlands (1990-2021).

A rapid increase in the incidence of anal squamous cell carcinoma (SCC) was reported in several countries over the past decades. This study assessed trends in epidemiology and primary treatment over a 32-year period (1990-2021) using the Netherlands Cancer Registry. The study population included 4273 patients, 44.2% male and 55.8% female (median age 63 years). The age-standardised incidence rate (European Standardised Rate, ESR) increased from 0.5 to 1.6 per 100,000, which entailed an average annual percentage change (AAPC) of 5.0% (95% confidence interval [CI]: 4.5%-5.8%). While incidence among females increased continuously over the total period (AAPC 4.9%; 95%CI: 4.4%-5.6%), to 1.8 per 100,000 ESR in 2021, incidence among males increased until 2016 (annual percentage change [APC] of 6.3%; 95%CI: 5.6%-10.7%), after which it seemed to stabilise (APC -2.1%; 95%CI: -16.8%-4.5%). Significant trends were also observed in distribution of age, tumour stage and primary treatment modalities. Five-year relative survival (RS) was estimated using the Pohar-Perme estimator, and this improved from 56.1% in 1990-1997 (95%CI: 49.3%-62.4%) to 67.9% in 2014-2021 (95%CI: 64.7%-70.9%), but remained poor for stage IV disease. Evaluation through a multivariable Poisson regression model demonstrated diagnosis in the most recent period to be independently associated with better RS, in addition to female sex, younger age, early disease stage and any treatment. In conclusion, the rising incidence of anal SCC seems to decline in males, but not in females, and advances in diagnostics and therapeutic management have likely contributed to improved prognosis.

Referral patterns of GIST patients: data from a nationwide study.

BACKGROUND: This study compares the characteristics, referral and treatment patterns and overall survival (OS) of gastrointestinal stromal tumor (GIST) patients treated in reference and non-reference centers in the Netherlands. PATIENTS AND METHODS: This retrospective cohort study on patients diagnosed between 2016 and 2019, utilises data from the Netherlands Cancer Registry and the Dutch Nationwide Pathology Database. Patients were categorized into two groups: patients diagnosed in or referred to reference centers and patients diagnosed in non-reference centers without referral. RESULTS: This study included 1,550 GIST patients with a median age of 67.0 in reference and 68.0 years in non-reference centers. Eighty-seven per cent of patients were diagnosed in non-reference centers, of which 36.5% (493/1,352) were referred to a reference center. Referral rates were higher for high-risk (62.2% [74/119]) and metastatic patients (67.2% [90/134]). Mutation analysis was performed in 96.9% and 87.6% of these cases in reference and in non-reference centers (p < 0.01), respectively. Systemic therapy was given in reference centers versus non-reference in 89.5% versus 82.0% (p < 0.01) of high-risk and in 94.1% versus 65.9% (p < 0.01) of metastatic patients, respectively. The proportion of positive resection margins and tumor rupture did not differ between reference and non-reference centers. Median OS was not reached. CONCLUSION: A substantial amount of metastatic GIST patients in non-reference centers did not receive systemic treatment. This might be due to valid reasons. However, optimisation of the referral strategy of GIST patients in the Netherlands could benefit patients. Further research is needed to explore reasons for not starting systemic treatment in metastatic GIST patients.

Epidemiology of adult meningioma: Report from the Dutch Brain Tumour Registry (2000-2019).

BACKGROUND AND PURPOSE: Meningiomas are the most common primary tumours of the central nervous system. This study aimed to provide comprehensive nationwide estimates on the incidence, prevalence and prognostic impact of meningioma diagnosis in the Netherlands. METHODS: Adult patients diagnosed with meningioma in 2000-2019 were selected from the Dutch Brain Tumour Registry (DBTR), part of the Netherlands Cancer Registry (NCR). Time trends in age-adjusted incidence and prevalence rates were evaluated using the estimated annual percentage change (EAPC). Relative survival rates were calculated using the Pohar Perme estimator. Case completeness of the DBTR/NCR was estimated through record linkage with one of the Dutch neuro-oncology centres. RESULTS: From a total of 23,454 cases of meningioma, 11,306 (48.2%) were histologically confirmed and 12,148 (51.8%) were radiological diagnoses. Over time, the incidence of diagnosis increased from 46.9 per 1,000,000 inhabitants (European Standardized Rate [ESR]) to 107.3 (EAPC 4.7%, p < 0.01), with an increase in the incidence of radiological diagnoses from 14.0 to 70.2 per 1,000,000 ESR (EAPC 9.1%, p < 0.01). The prevalence of meningioma was estimated at 1012/1,000,000 on 1 January 2020, with almost 17,800 individuals having had a diagnosis of meningioma. Relative survival rate at 10 years for grade 1 meningiomas was 91.0% (95% confidence interval [CI] 89.4%-92.3%), 71.3% (95% CI 66.8%-75.2%) for grade 2 meningiomas and 36.4% (95% CI 27.3%-45.6%) for grade 3 meningiomas. Local case completeness was estimated at 97.6% for histologically confirmed meningiomas and 84.5% for radiological diagnoses. CONCLUSION: With a near-complete registry, meningioma prevalence was estimated at over 1000 per 1,000,000 inhabitants.

Validation of the updated renal graded prognostic assessment (GPA) for patients with renal cancer brain metastases treated with gamma knife radiosurgery.

INTRODUCTION: Prognosis of patients with brain metastasis (BM) from renal cell carcinoma (RCC) is relevant for treatment decisions and can be estimated with the Renal Graded Prognostic Assessment (GPA). The aim of this study is to validate the updated version of this instrument in a cohort treated with Gamma Knife radiosurgery (GKRS) without prior local intracerebral therapy. METHODS: Between 2007 and 2018, 106 RCC patients with BM were treated with GKRS. They were categorized according to the updated Renal GPA. Overall survival (OS), distant intracranial failure and local failure were estimated using the Kaplan-Meier method and risk factors were identified with Cox proportional hazard regressions. RESULTS: Median OS was 8.6 months. Median OS for GPA categories 0.0-1.0 (15%), 1.5-2.0 (12%), 2.5-3.0 (35%) and 3.5-4.0 (29%) was 2.9, 5.5, 8.1 and 20.4 months, respectively. Karnofsky performance status < 90, serum hemoglobin ≤ 12.5 g/dL, age > 65 years and time from primary diagnosis to brain metastasis < 1 year were significantly related with shorter survival, while presence of extracranial disease, the volume and total number of BM had no significant impact on OS. A total count of > 4 BM was the only predictive factor for distant intracranial failure, while none of the investigated factors predicted local failure. CONCLUSIONS: This study confirms the updated Renal GPA in an independent cohort as a valuable instrument to estimate survival in patients with BM from RCC treated with GKRS.

Nationwide evaluation of mutation-tailored treatment of gastrointestinal stromal tumors in daily clinical practice.

BACKGROUND: Molecular analysis of KIT and PDGFRA is critical for tyrosine kinase inhibitor treatment selection of gastrointestinal stromal tumors (GISTs) and hence recommended by international guidelines. We performed a nationwide study into the application of predictive mutation testing in GIST patients and its impact on targeted treatment decisions in clinical practice. METHODS: Real-world clinical and pathology information was obtained from GIST patients with initial diagnosis in 2017-2018 through database linkage between the Netherlands Cancer Registry and the nationwide Dutch Pathology Registry. RESULTS: Predictive mutation analysis was performed in 89% of the patients with high risk or metastatic disease. Molecular testing rates were higher for patients treated in expertise centers (96%) compared to non-expertise centers (75%, P < 0.01). Imatinib therapy was applied in 81% of the patients with high risk or metastatic disease without patient's refusal or adverse characteristics, e.g., comorbidities or resistance mutations. Mutation analysis that was performed in 97% of these imatinib-treated cases, did not guarantee mutation-tailored treatment: 2% of these patients had the PDGFRA p.D842V resistance mutation and 7% initiated imatinib therapy at the normal instead of high dose despite of having a KIT exon 9 mutation. CONCLUSION: In conclusion, nationwide real-world data show that over 81% of the eligible high risk or metastatic disease patients receive targeted therapy, which was tailored to the mutation status as recommended in guidelines in 88% of cases. Therefore, still 27% of these GIST patients misses out on mutation-tailored treatment. The reasons for suboptimal uptake of testing and treatment require further study.

Minimal Increase in Survival Throughout the Years in Patients with Soft Tissue Sarcoma with Synchronous Metastases: Results of a Population-Based Study.

BACKGROUND: Treatment options for patients with metastatic soft tissue sarcoma (STS) have increased in the last decade. We aimed to examine whether this is associated with improved overall survival (OS) in patients with STS with synchronous metastases. PATIENTS AND METHODS: Patients diagnosed with STS and synchronous metastases from 1989 to 2014 were queried from The Netherlands Cancer Registry. Trends in OS were assessed by the Kaplan-Meier method and log-rank test in time intervals of 5 years, for the whole study population and in subgroups for liposarcomas, leiomyosarcoma, and other STS subtypes. A multivariable Cox regression analysis was performed to identify characteristics prognostic for OS. RESULTS: Median OS of the 1,393 identified patients did not improve significantly over the years from 5.8 months in 1989-1994 to 8.1 months in 2010-2014, but there was an evident trend. Median OS was prolonged in the subgroups of liposarcomas (3.6 to 9.3 months), leiomyosarcomas (11.3 to 14.6 months), and other STS subtypes (5.7 to 6.3 months), although there were no significant improvements in OS over the years. Primary tumor site in one of the extremities and surgery in an academic center had a favorable effect on OS, whereas significant negative predictors were no treatment, elderly age, STS subtype other than liposarcoma or leiomyosarcoma, high or unknown grade, and nodal involvement. CONCLUSION: Although overall survival of patients with STS with synchronous metastases in this nationwide and "real-life" population has improved over the years, the improvement was not statistically significant, despite new treatment options. IMPLICATIONS FOR PRACTICE: Treatment of patients with metastatic soft tissue sarcoma (STS) has changed in the past years, with new drugs such as trabectedin (2007) and pazopanib (2012) becoming available. By using data from the nationwide Netherlands Cancer Registry, the impact of these changes in treatment policies on survival is analyzed in a "real-life" population of patients with STS with synchronous metastases, rather than in a strictly selected trial population. Unfortunately, overall survival improved only minimally and not significantly for these patients diagnosed from 1989 to 2014. Hopefully, the advent of novel treatment options, such as eribulin and olaratumab, will further improve the outcome of this patient group.

Between-hospital variation in mortality and survival after glioblastoma surgery in the Dutch Quality Registry for Neuro Surgery.

PURPOSE: Standards for surgical decisions are unavailable, hence treatment decisions can be personalized, but also introduce variation in treatment and outcome. National registrations seek to monitor healthcare quality. The goal of the study is to measure between-hospital variation in risk-standardized survival outcome after glioblastoma surgery and to explore the association between survival and hospital characteristics in conjunction with patient-related risk factors. METHODS: Data of 2,409 adults with first-time glioblastoma surgery at 14 hospitals were obtained from a comprehensive, prospective population-based Quality Registry Neuro Surgery in The Netherlands between 2011 and 2014. We compared the observed survival with patient-specific risk-standardized expected early (30-day) mortality and late (2-year) survival, based on age, performance, and treatment year. We analyzed funnel plots, logistic regression and proportional hazards models. RESULTS: Overall 30-day mortality was 5.2% and overall 2-year survival was 13.5%. Median survival varied between 4.8 and 14.9 months among hospitals, and biopsy percentages ranged between 16 and 73%. One hospital had lower than expected early mortality, and four hospitals had lower than expected late survival. Higher case volume was related with lower early mortality (P = 0.031). Patient-related risk factors (lower age; better performance; more recent years of treatment) were significantly associated with longer overall survival. Of the hospital characteristics, longer overall survival was associated with lower biopsy percentage (HR 2.09, 1.34-3.26, P = 0.001), and not with academic setting, nor with case volume. CONCLUSIONS: Hospitals vary more in late survival than early mortality after glioblastoma surgery. Widely varying biopsy percentages indicate treatment variation. Patient-related factors have a stronger association with overall survival than hospital-related factors.

Centralization of ovarian cancer in the Netherlands: Hospital of diagnosis no longer determines patients' probability of undergoing surgery.

OBJECTIVE: Surgical care for advanced stage epithelial ovarian cancer (EOC) patients has been centralized in the Netherlands since 2012. We evaluated whether the likelihood for patients to undergo surgery depends on the hospital of initial diagnosis before and after centralization of surgical care. METHODS: Patients with EOC FIGO stage IIB-IV, diagnosed in the Netherlands between 2000 and 2015, were identified from the Netherlands Cancer Registry. Multilevel multivariate logistic regression was used to study the association between hospital of diagnosis and patients' likelihood of undergoing surgery in subsequent time periods. Furthermore, changes in overall survival were analyzed by multivariable Cox regression models. RESULTS: 15,314 EOC patients were selected from the NCR. Hospital of diagnosis was identified as a significant level for patients' likelihood of undergoing surgery in 2000-2005 (LR test p<0.001), as well as in 2006-2011 (LR test p=0.002) but not in 2012-2015 (LR test p=0.127). Patients who underwent surgery in 2012-2015 had a better survival when compared to 2006-2011 (HR 0.90(0.84-0.96)). CONCLUSION: This study shows that centralization of surgical care resolved the variation between hospitals in the probability to undergo cytoreductive surgery for patients with advanced EOC. Since centralization was established in 2012, the decision to operate patients seems solely attributable to patient and tumor characteristics. This supports the growing evidence in favor of centralizing (surgical) treatment for complex and heterogeneous diseases such as EOC.

Adherence to Guidelines for Adult (Non-GIST) Soft Tissue Sarcoma in the Netherlands: A Plea for Dedicated Sarcoma Centers.

INTRODUCTION: Optimal management of soft tissue sarcoma (STS) remains a challenge. A nationwide survey assessed the quality of STS care in the Netherlands, thereby aiming to identify potentialities for improvement through more centralized disease management. METHODS: From the Netherlands Cancer Registry (NCR), data were obtained on 3317 adult STS patients (excluding gastrointestinal stromal tumor, GIST) diagnosed in 2006-2011. Logistic regression models were employed to compare outcomes on selected clinical indicators reflecting prevailing STS guidelines between high-volume (≥10 resections annually) and low-volume (<10 resections) hospitals, between academic and general hospitals, and between sarcoma research centers and other hospitals, adjusted for case mix. Analyses were performed on imputed datasets (m = 50), generated through multiple imputations by chained equations. RESULTS: Overall, 89% of patients underwent surgical resection. Resection status remained unknown in 24% (excluding those with metastasized disease), and grade was not documented for one-third of tumors. Microscopic residual disease was detected in 20% with an increased risk for older patients, larger and deeply located tumors, and those located in the (retro)peritoneum or upper extremity. Almost half of patients with an R1 resection received adjuvant radiotherapy. Following adjustment for case mix factors, patients treated in high-volume hospitals less often had macroscopic residual disease (R2 resection; adjusted odds ratio: 0.54). A strongly skewed distribution of surgical volumes was observed. CONCLUSIONS: These survey results indicate a potential for improving Dutch STS care. More centralized sarcoma management should improve definitive pathology reporting on tumor characteristics, adherence to treatment guidelines and overall disease outcome.

The influence of a composite hospital volume on outcomes for gastric cancer surgery: A Dutch population-based study.

BACKGROUND: Volume-outcome associations for complex surgical procedures have motivated centralization of care worldwide. The aim of this study was to investigate the association between overall hospital experience with complex upper gastrointestinal (GI) cancer resections and outcomes after gastric cancer surgery. METHODS: Data on all patients (n = 4837) who underwent a resection for non metastatic invasive gastric cancer between 2005 and 2014 were obtained from the Netherlands Cancer Registry (NCR). Annual hospital volume categories were based on the combined volume of gastrectomies, esophagectomies, and pancreatectomies (composite hospital volume). Volume-outcome analyses were performed for lymph node yield, 30-day mortality, and overall survival. RESULTS: The proportion of gastric cancer resections performed in hospitals with an annual composite hospital volume of ≥40 upper GI cancer resections increased from 6% in 2005 to 80% in 2014. A higher composite hospital volume was univariably associated with a higher lymph node yield, lower 30-day mortality, and increased overall survival. Statistical significance was lost after adjusting for case mix. But, sub group analysis including only elderly patients (≥75 years) showed a significant association between composite hospital volume and 30-day mortality. CONCLUSION: In the Netherlands, an increasing proportion of gastric cancer resections is performed in hospitals with a high composite hospital volume of gastric, esophageal, and pancreatic cancer resections. Special attention is warranted to referral of elderly patients, as these patients might specifically benefit from this centralization.

Adherence to cancer treatment guidelines: influence of general and cancer-specific guideline characteristics.

Background: Guideline adherence remains a challenge in clinical practice, despite guidelines' ascribed potential to improve patient outcomes. We studied the level of adherence to recommendations from Dutch national cancer treatment guidelines, and the influence of general and cancer-specific guideline characteristics on adherence. Methods: Based on data from a national cancer registry, adherence was evaluated for 15 treatment recommendations for breast, colorectal, prostate and lung cancer, and melanoma. Recommendations were selected by representatives of the medical specialist associations responsible for developing and implementing the guidelines. We used multivariable multilevel analysis to calculate mean adherence and variation between individual hospitals. Results: Mean adherence to the different treatment recommendations ranged from 40 to 99%. Adherence differed only slightly between older and newer guidelines and between recommendations with low, moderate or high levels of evidence (range 79-84% and 77-91%, respectively), while adherence differed more between recommendations for different cancer types (range 54-99%), different treatment modalities (adherence ranged from 40 to 92%) or recommendations that advised against or recommended in favour of particular treatment (adherence ranged from 75 to 98%). Conclusion: We found significant variation in adherence between different cancer treatment guidelines. While some guideline characteristics that seem to explain this variation may be considered difficult to modify, the potential for variance across cancer types and treatment modalities suggests that adherence could be further improved. At the same time, these results warrant tailored strategies for the improvement of adherence to clinical practice guidelines.

Worse Survival in Elderly Patients with Extremity Soft-Tissue Sarcoma.

BACKGROUND: Nearly half of soft-tissue sarcoma (STS) patients are over the age of 65, and the behavior of cancer in these elderly patients is poorly understood. The aim of this study was to assess the impact of age, sarcoma histotype, grade, stage, and treatment modalities on survival of extremity STS (ESTS) patients. METHODS: Patients ≥18 years diagnosed with ESTS between 1989 and 2008 were selected from the Netherlands Cancer Registry. Survival rates and patient and treatment characteristics were analyzed for all patients. Relative survival and relative excess risk of death were estimated for young (<65 years) and older (>65 years) patients. RESULTS: Overall, 3066 patients were included in this study. Histotype was different between young (<65 years) and elderly (>65 years) patients (p < 0.001). Patients over the age of 65 were more often diagnosed with high-stage ESTS and an increasing proportion of high-grade ESTS (p < 0.001). The proportion of patients who received no treatment increased with age, and the elderly received fewer combined-modality treatments. Age was significantly associated with relative 5-year survival [72.7 % for younger patients and 43.8 % for the oldest elderly (>85 years)]. In multivariable analysis, age still remained a significant prognostic factor. CONCLUSIONS: Different distribution of sarcoma histotypes, more high-stage and high-grade sarcomas at diagnosis, less aggressive treatment, and worse survival rates emphasize the need for optimizing sarcoma research and care of the elderly.

Age as an independent prognostic factor for survival of localised synovial sarcoma patients.

BACKGROUND: We performed a retrospective nationwide study to explore age as a prognostic factor in synovial sarcoma patients. METHODS: Data on 613 synovial sarcoma patients were obtained from the Netherlands Cancer Registry. The prognostic relevance of age groups (children, adolescent and young adults (AYAs), adults, and elderly) was estimated by Kaplan-Meier survival curves and multivariable Cox-proportional hazards modelling. RESULTS: A total of 461 patients had localised disease at diagnosis. The 5-year overall survival (OS) was 89.3±4.6%, 73.0±3.8%, 54.7±3.6%, and 43.0±7.0% in children (n=54), AYAs (n=148), adults (n=204), and elderly (n=55), respectively. Treatment modalities had no significant effect on survival in the univariable analysis. Multivariable analysis identified age at diagnosis, tumour localisation, and tumour size as significant factors affecting OS. Both tumour localisation and size were equally distributed over the age groups. CONCLUSIONS: We show that outcome of synovial sarcoma patients significantly decreases with age regardless of primary tumour site, size, and treatment.

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.

Bone sarcoma follow-up; a nationwide analysis of oncological events after initial treatment.

Aim: Follow-up strategies for high-grade bone sarcomas have been optimized to facilitate early detection of local recurrence and distant metastasis. The ideology is that early detection enables early treatment presuming better survival. However, the clinical value for each individual patient remains questionable. This study aims to evaluate oncological events after initial treatment in order to assess current follow-up strategies for high-grade bone sarcomas in the Netherlands. Patients and Methods: A retrospective cohort study was conducted based on a national registry. All cases were retrieved from the Netherlands Cancer Registry. Our study consisted of 393 patients treated between 2007 and 2011 with complete follow-up data. Baseline characteristics were analysed for all entities. Local recurrence and distant metastasis was analysed along with overall survival for high-grade chondrosarcoma, high-grade osteosarcoma, Ewing sarcoma and chordoma. Results: Median follow-up was 8,3 years for high-grade chondrosarcoma, 4,9 for high-grade osteosarcoma, 3,8 for Ewing sarcoma and 7,5 for chordoma. Median time to local recurrence and distant metastasis was 1,2 years for high-grade osteosarcoma and 1,5 years for Ewing sarcoma. For high-grade osteosarcoma with localized disease at presentation, 0.09 new distant metastatic events per patient per year were seen after five years of follow-up with 11,1 patients needed to follow-up for any event. Five-year overall survival was 60,0% for high-grade chondrosarcoma, 50,0% for high-grade osteosarcoma, 45,3% for Ewing sarcoma and 71,4% for chordoma. Conclusions: This nationwide study shows a plateau in local recurrences and distant metastatic events after four years of treatment for patients with high-grade osteosarcoma and Ewing sarcoma. Due to a lack of reliable evidence however, we were not able to provide additional guidance on follow-up intervals and duration. Collaborative research with larger groups is needed in order to provide a solid scientific recommendation for follow-up in the heterogenous patient population with bone sarcoma.

Trends in Incidence and Survival of 1496 Patients with Mucosal Melanoma in The Netherlands (1990-2019).

BACKGROUND: Mucosal melanoma (MM) is a rare tumour with a poor prognosis. Over the years, immune and targeted therapy have become available and have improved overall survival (OS) for patients with advanced cutaneous melanoma (CM). This study aimed to assess trends in the incidence and survival of MM in the Netherlands against the background of new effective treatments that became available for advanced melanoma. METHODS: We obtained information on patients diagnosed with MM during 1990-2019 from the Netherlands Cancer Registry. The age-standardized incidence rate and estimated annual percentage change (EAPC) were calculated over the total study period. OS was calculated using the Kaplan-Meier method. Independent predictors for OS were assessed by applying multivariable Cox proportional hazards regression models. RESULTS: In total, 1496 patients were diagnosed with MM during 1990-2019, mostly in the female genital tract (43%) and the head and neck region (34%). The majority presented with local or locally advanced disease (66%). The incidence remained stable over time (EAPC 3.0%, p = 0.4). The 5-year OS was 24% (95%CI: 21.6-26.0%) with a median OS of 1.7 years (95%CI: 1.6-1.8). Age ≥ 70 years at diagnosis, higher stage at diagnosis, and respiratory tract location were independent predictors for worse OS. Diagnosis in the period 2014-2019, MM located in the female genital tract, and treatment with immune or targeted therapy were independent predictors for better OS. CONCLUSION: Since the introduction of immune and targeted therapies, OS has improved for patients with MM. However, the prognosis of MM patients is still lower compared to CM, and the median OS of patients treated with immune and targeted therapies remains fairly short. Further studies are needed to improve outcomes for patients with MM.

Histological type is not an independent prognostic factor for the risk pattern of breast cancer recurrences.

Invasive lobular breast cancer (ILC) is less common than invasive ductal breast cancer (IDC) and appears to have a distinct biology. Inconsistent findings regarding disease-free survival (DFS) are probably due to the fact that histologic type is related to hormone receptor status. This study aims to determine whether the type of the primary breast cancer histology is an independent prognostic factor for DFS, the risk pattern of loco-regional recurrences and distant metastases (DM), and whether it is a prognostic factor for the site of DM. All Dutch women diagnosed between 2003 and 2005 with ILC (n = 2,949) or IDC (n = 22,378) were selected from the Netherlands Cancer Registry. DFS was assessed using proportional hazard regression analysis. Compared to patients with IDC, those with ILC were significantly older and more likely to have more than three positive lymph nodes and have larger, better differentiated, more multifocal, and hormone receptor positive tumors (all P < 0.001). ILC was more likely to metastasize to the gastrointestinal organs and bones and less likely to the lung, central nervous system, and lymph nodes. Within the ER+PR+ and ER+PR- subgroups ILC was still more likely to metastasize to gastrointestinal organs and less likely to the lung. The timing of recurrence was correlated to hormone receptor status, independent of histological type. Highest risks were observed among ER-PR- patients within 2 years of surgery. Multivariable analysis showed that histological type is not an independent significant prognostic factor of DFS for the first 3 years post-surgery and thereafter (<3 years HR 0.91, 95 % CI 0.78-1.06, >3 years HR 1.07, 95 % CI 0.88-1.30). Histological type should not be considered an important prognostic factor for the risk and risk pattern of recurrences.

Overall Survival of Patients with Myxofibrosarcomas: An Epidemiological Study.

Myxofibrosarcoma (MFS) is a rare mesenchymal soft tissue sarcoma type, with a high local recurrence (LR) rate. Robust epidemiological data on MFS are lacking. We, therefore, aimed to identify prognostic factors and describe real-life outcomes of a large cohort of 908 MFS patients obtained from the nationwide database of the Netherlands Cancer Registry and diagnosed between 2002 and 2019. Median Overall survival (OS) was 155 (range 0.1-215) months, with a five-year OS of 67.7%. No improvement of OS was found over time. Multivariable Cox regression survival analysis demonstrated known prognostic factors for OS, such as older age, tumour size, and histological grade with the addition of sex. Surgery at sarcoma expertise centres, instead of general hospitals, was associated with better OS outcomes. In a subcohort of 177 patients, 39% developed LR with a median time to recurrence of 20 months. From LR on, the median OS was 64.0 months (CI 95% 38.5-89.5). In 28%, distant metastases were diagnosed with a median OS of 34.3 months (CI 95% 28.8-39.8) after diagnosis of the primary tumour. In this largest nationwide cohort so far, survival outcomes and recurrence rates for MFS patients did not improve over time, emphasizing the need to improve treatment strategies and suggesting a role for sarcoma expertise centres.

Rare central nervous system tumors in adults: a population-based study of ependymomas, pilocytic astrocytomas, medulloblastomas, and intracranial germ cell tumors.

Background: Ependymomas, pilocytic astrocytomas, medulloblastomas, and intracranial germ cell tumors occur relative frequently in children, but are rare central nervous system (CNS) tumors in adults. In this population-based survey, we established incidence, treatment, and survival patterns for these tumors diagnosed in adult patients (≥18 years) over a 30-year period (1989-2018). Methods: Data on 1384 ependymomas, 454 pilocytic astrocytomas, 205 medulloblastomas, and 112 intracranial germ cell tumors were obtained from the Netherlands Cancer Registry (NCR) on the basis of a histopathological diagnosis. For each tumor type, age-standardized incidence rates and estimated annual percentage change were calculated. Trends in incidence and main treatment modalities were reported per 5-year periods. Overall survival was calculated using the Kaplan-Meier method, and relative survival rates were estimated using the Pohar-Perme estimator. Results: Incidence and survival rates remained generally stable for pilocytic astrocytomas, medulloblastomas, and germ cell tumors. Increasing incidence was observed for spinal ependymomas, mostly for myxopapillary ependymomas, and survival improved over time for grade II ependymomas (P < .01). Treatment patterns varied over time with shifting roles for surgery in ependymomas and for chemotherapy and radiation in medulloblastomas and germinomas. Conclusions: The study provides baseline information for highly needed national and international standard treatment protocols, and thus for further improving patient outcomes in these rare CNS tumors.

Incidence of unplanned excisions of soft tissue sarcomas in the Netherlands: A population-based study.

INTRODUCTION: Timely recognition of soft tissue sarcomas (STS) remains challenging, potentially leading to unplanned excisions (also known as 'whoops procedures'). This population-based study charted the occurrence of unplanned excisions and identified associated patient, tumour, and treatment-related characteristics. Furthermore, it presents an overview of the outcomes and clinical management following an unplanned excision. METHODS: From the Netherlands Cancer Registry (NCR) database, information was obtained on 2187 adult patients diagnosed with STS in 2016-2019 who underwent surgery. Tumours located in the mediastinum, heart or retroperitoneum were excluded, as well as incidental findings. Differences between patients with planned and unplanned excisions were assessed with chi-square tests and a multivariable logistic regression model. RESULTS: Overall, unplanned excisions comprise 18.2% of all first operations for STS, with a quarter of them occurring outside a hospital. Within hospitals, the unplanned excision rate was 14.4%. Unplanned excisions were more often performed on younger patients, and tumours unsuspected of being STS prior to surgery were generally smaller (≤5 cm) and superficially located. Preoperative imaging was omitted more frequently in these cases. An unplanned excision more often resulted in positive margins, requiring re-excision. Patients who had an unplanned excision outside of a sarcoma centre were more often discussed at or referred to a sarcoma centre, particularly in case of residual tumour. DISCUSSION: Potential improvement in preventing unplanned excisions may be achieved by better compliance to preoperative imaging and referral guidelines, and stimulating continuous awareness of STS among general surgeons, general practitioners and private practices.