Improving survival in advanced melanoma patients: a trend analysis from 2013 to 2021

Background

The prognosis of advanced melanoma patients has significantly improved over the years. We aimed to evaluate the survival per year of diagnosis.

Methods

All systemically treated patients diagnosed with advanced melanoma from 2013 to 2021 were included from the Dutch Melanoma Treatment Registry. Baseline characteristics and overall survival (OS) were compared between the different years of diagnosis. A multivariable Cox proportional hazards model was used to estimate the association between year of diagnosis and OS.

Findings

For this cohort study, we included 6260 systemically treated advanced melanoma patients. At baseline, there was an increase over the years in age, the percentage of patients with an ECOG PS ≥ 2, with brain metastases, and a synchronous diagnosis of primary and unresectable melanoma. Median OS increased from 11.2 months (95% CI 10.0-12.4) for patients diagnosed in 2013 to 32.0 months (95% CI 26.6-36.7) for patients diagnosed in 2019. Median OS was remarkably lower for patients diagnosed in 2020 (26.6 months; 95% CI 23.9-35.1) and 2021 (24.0 months; 95% CI 20.4-NR). Patients diagnosed in 2020 and 2021 had a higher hazard of death compared to patients diagnosed in 2019, although this was not significant. The multivariable Cox regression showed a lower hazard of death for the years of diagnosis after 2013. In contrast, patients diagnosed in 2020 and 2021 had a higher hazard of death compared to patients diagnosed in 2019.

Interpretation

After a continuous survival improvement for advanced melanoma patients between 2013 and 2019, outcomes of patients diagnosed in 2020 and 2021 seem poorer. This trend of decreased survival remained after correcting for known prognostic factors and previous neoadjuvant or adjuvant treatment, suggesting that it is explained by unmeasured factors, which-considering the timing-could be COVID-19-related.

Funding

For the Dutch Melanoma Treatment Registry (DMTR), the Dutch Institute for Clinical Auditing foundation received a start-up grant from governmental organization The Netherlands Organization for Health Research and Development (ZonMW, project number 836002002). The DMTR is structurally funded by Bristol-Myers Squibb, Merck Sharpe & Dohme, Novartis, and Roche Pharma. Roche Pharma stopped funding in 2019, and Pierre Fabre started funding the DMTR in 2019. For this work, no funding was granted.

Does Centralization of Radical Prostatectomy Reduce the Incidence of Postoperative Urinary Incontinence?

Background

On the basis of previous analyses of the incidence of urinary incontinence (UI) after radical prostatectomy (RP), the hospital RP volume threshold in the Netherlands was gradually increased from 20 per year in 2017, to 50 in 2018 and 100 from 2019 onwards.

Objective

To evaluate the impact of hospital RP volumes on the incidence and risk of UI after RP (RP-UI).

Design setting and participants

Patients who underwent RP during 2016-2020 were identified in the claims database of the largest health insurance company in the Netherlands. Incontinence was defined as an insurance claim for ≥1 pads/d.

Outcome measurements and statistical analysis

The relationship between hospital RP volume (HV) and RP-UI was assessed via multivariable analysis adjusted for age, comorbidity, postoperative radiotherapy, and lymph node dissection.

Results and limitations

RP-UI incidence nationwide and by RP volume category did not decrease significantly during the study period, and 5-yr RP-UI rates varied greatly among hospitals (19-85%). However, low-volume hospitals (≤120 RPs/yr) had a higher percentage of patients with RP-UI and higher variation in comparison to high-volume hospitals (>120 RPs/yr). In comparison to hospitals with low RP volumes throughout the study period, the risk of RP-UI was 29% lower in hospitals shifting from the low-volume to the high-volume category (>120 RPs/yr) and 52% lower in hospitals with a high RP volume throughout the study period (>120 RPs/yr for 5 yr).

Conclusions

A focus on increasing hospital RP volumes alone does not seem to be sufficient to reduce the incidence of RP-UI, at least in the short term. Measurement of outcomes, preferably per surgeon, and the introduction of quality assurance programs are recommended.

Patient summary

In the Netherlands, centralization of surgery to remove the prostate (RP) because of cancer has not yet improved the occurrence of urinary incontinence (UI) after surgery. Hospitals performing more than 120 RP operations per year had better UI outcomes. However, there was a big difference in UI outcomes between hospitals.

Oncoplastic breast conserving surgery: is there a need for standardization? Results of a nationwide survey

Introduction The NABON Breast Cancer Audit showed that more than 70% of the Dutch women undergoing surgery for breast cancer (BC) maintained their breast contour by breast conserving surgery (BCS) or by immediate reconstruction after ablative surgery. The proportion of oncoplastic surgery applied in patients undergoing breast conserving treatment (BCT) remains unknown. The aim of our study was to assess the need for standardization of oncoplastic breast conserving surgery (OPBCS) in an attempt to enable measurement of the quality of OPBCS. Methods To gain a better understanding of current practice in OPBCS we sent a questionnaire to all breast surgeons in the Netherlands who are member of the breast surgery working group (n=134). Results A total of 60 breast surgeons, representing different hospitals in the Netherlands, responded. 61.7% of the breast surgeons performed BCS in 60%-100% of their patients. 68.3% responded that BCS was performed using OPS techniques in up to 40% of their patients. OPBCS was defined as level I volume displacement by 45.2% of the breast surgeons and as BCS performed by a breast surgeon and plastic surgeon together by 32.3% of the breast surgeons. 94.5% indicated that there is a need for standardization of the definition of OPBCS in the Netherlands. Conclusion This study demonstrates that OPBCS is a major part of daily clinical practice of Dutch breast surgeons treating BC patients. Despite of this, there is no clear definition of OPS in BCT in the Netherlands. Only after standardization, a classification code and quality indicator can be initiated for OPBCS. Ultimately, this will facilitate improvement in quality of BC care.

Long-term survival of patients with advanced melanoma treated with BRAF-MEK inhibitors

Recent results of patients with advanced melanoma treated with first-line BRAF-MEK inhibitors in clinical trials showed 5-year survival in one-third of patients with a median overall survival (OS) of more than 2 years. This study aimed to investigate these patients' real-world survival and identify the characteristics of long-term survivors. The study population consisted of patients with advanced cutaneous melanoma with a BRAF-V600 mutated tumor who were treated with first-line BRAF-MEK inhibitors between 2013 and 2017. Long-term survival was defined as a minimum OS of 2 years from start therapy. The median progression-free survival (mPFS) and median OS (mOS) of real-world patients ( n  = 435) were respectively 8.0 (95% CI, 6.8-9.4) and 11.7 (95% CI, 10.3-13.5) months. Two-year survival was reached by 28% of the patients, 22% reached 3-year survival and 19% reached 4-year survival. Real-world patients often had brain metastases (41%), stage IV M1c disease (87%), ECOG PS ≥2 (21%), ≥3 organ sites (62%) and elevated LDH of ≥250 U/I (49%). Trial-eligible real-world patients had an mOS of 17.9 months. Patients surviving more than 2 years ( n  = 116) more often had an ECOG PS ≤1 (83%), normal LDH (60%), no brain metastases (60%), no liver metastases (63%) and <3 organ sites (60%). Long-term survival of real-world patients treated with first-line BRAF-MEK inhibitors is significantly lower than that of trial patients, which is probably explained by poorer baseline characteristics of patients treated in daily practice. Long-term survivors generally had more favorable characteristics with regard to age, LDH level and metastatic sites, compared to patients not reaching long-term survival.

End-of-Life Use of Systemic Therapy in Patients With Advanced Melanoma: A Nationwide Cohort Study

PURPOSE:

The introduction of immune checkpoint inhibitors and targeted therapies improved the overall survival of patients with advanced melanoma. It is not known how often these costly treatments with potential serious side effects are ineffectively applied in the last phase of life. This study aimed to investigate the start of a new systemic therapy within 45 and 90 days of death in Dutch patients with advanced melanoma.

METHODS:

We selected patients who were diagnosed with unresectable IIIC or stage IV melanoma, registered in the Dutch Melanoma Treatment Registry, and died between 2013 and 2019. Primary outcome was the probability of starting a new systemic therapy 45 and 90 days before death. Secondary outcomes were type of systemic therapy started, grade 3/4 adverse events (AEs), and the total costs of systemic therapies.

RESULTS:

Between 2013 and 2019, 3,797 patients with unresectable IIIC or stage IV melanoma were entered in the registry and died. The percentage of patients receiving a new systemic therapy within 45 and 90 days before death was significantly different between Dutch melanoma centers (varying from 6% to 23% and 20% to 46%, respectively). Thirteen percent of patients (n = 146) developed grade 3/4 AEs in the last period before death. The majority of patients with an AE required hospital admission (n = 102, 69.6%). Mean total costs of systemic therapy per cohort year of the patients who received a new systemic therapy within 90 days before death were 2.3%-2.8% of the total costs spent on melanoma therapies.

CONCLUSION:

The minority of Dutch patients with metastatic melanoma started a new systemic therapy in the last phase of life. However, the percentages varied between Dutch melanoma centers. Financial impact of these therapies in the last phase of life is relatively small.

Adjuvant treatment of in-transit melanoma: Addressing the knowledge gap left by clinical trials

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Background: Few clinical trials address the efficacy of adjuvant systemic treatment in patients with ITM. This study describes the efficacy of adjuvant systemic therapy of ITM patients beyond the clinical trial setting. Methods: All stage III adjuvant-treated melanoma patients registered in the nationwide Dutch Melanoma Treatment Registry between 01-07-2018 and 31-12-2020 were included. Patients were divided into three groups: patients with ITM only, with ITM and nodal disease, and patients with nodal disease only. Differences in recurrence patterns were analysed. An exploratory analysis was performed for stage III patients who underwent surgical resection without adjuvant treatment. Recurrence-free survival (RFS) and overall survival (OS) at 12-months were assessed. Results: A total of 1037 stage III melanoma patients received adjuvant anti-PD-1 therapy, and 260 underwent surgical resection only. Of the adjuvant-treated patients, 16.9% had ITM only, 15.5% had ITM with nodal disease, and 66.8% had nodal disease only. Of the surgical resection only patients 20.4% had ITM only, 12.3% had ITM with nodal disease and 67.3% had nodal disease only. In the adjuvant-treated patients, 12-months RFS was comparable between patients with ITM only and patients with nodal disease only (71.1% vs. 72.2% respectively, p = 0.95), but significantly lower for patients with ITM and nodal disease (57.1%; ITM with nodal disease vs. ITM-only p = 0.01, and ITM with nodal disease vs. nodal disease only p < 0.01). Locoregional metastases occurred as first recurrence site in 72.7% of ITM-only patients, 42.9% of ITM and nodal disease patients and 38.9% of patients with nodal disease only, while distant recurrences occurred in 18.2% of patients with ITM only, in 36.7% of patients with ITM and nodal disease, and in 42.3% of patients with nodal disease only (p = 0.01). OS at 12-months was significantly higher for ITM-only patients compared to patients with ITM and nodal disease (97.7% vs. 90.6%, p < 0.01), and was better compared to patients with nodal disease only (97.7% vs. 94.4%, p = 0.05). OS at 12-months was comparable for patients with ITM and nodal disease and patients with nodal disease only (p = 0.19). In general, surgery-only ITM patients were older and had a worse performance score. 12-months RFS appeared worse compared to adjuvant-treated ITM patients (36.6% vs. 68.3%). In this group of surgery-only ITM patients OS at 12-months also appeared worse compared to adjuvant-treated ITM patients (89.7% vs. 95.5%). Conclusions: RFS rates in ITM-only patients are similar to non-ITM patients, while RFS in patients with ITM and nodal disease is shorter. Adjuvant-treated patients with ITM without nodal disease less often experience distant recurrences and have a superior OS compared to other adjuvant stage III patients. Our results suggest that other treatment strategies for ITM patients with nodal disease should be considered.

Management of checkpoint inhibitor toxicity and survival in patients with advanced melanoma

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Background: Management of checkpoint-inhibitor-induced immune-related adverse events (irAEs) is primarily based on expert opinion. Recent studies have suggested detrimental effects of immunosuppressive treatment with anti-TNF on checkpoint-inhibitor efficacy. Methods: Advanced melanoma patients experiencing grade ≥3 irAEs after treatment with first-line ipilimumab-nivolumab between 2015 and 2021 were included from the Dutch Melanoma Treatment Registry. Progression-free survival (PFS), overall survival (OS) and melanoma-specific survival (MSS) were analyzed according to toxicity management regimen. A cox proportional hazards model was used to account for the confounders age, sex, performance status, lactate dehydrogenase, site of metastases and type of irAE. Results: Out of 771 ipilimumab-nivolumab treated patients, 350 were treated with immunosuppression for severe irAEs. Of these patients, 235 received steroids only and 115 received steroids with second-line immunosuppressants consisting of anti-TNF, mycophenolic acid, tacrolimus and other immunosuppressants. Median PFS was significantly longer for patients treated with steroids (11.3 months) than for patients treated with steroids and second-line immunosuppressants (5.4 months; HR 1.43; 95%CI 1.07-1.90; p = 0.01). Median OS was also significantly longer for the steroids group (46.1 months) than for the steroids and second-line immunosuppressants group (22.5 months; HR 1.64; 95%CI 1.16-2.32; p = 0.005). Results for MSS were similar (not reached versus 28.8 months; HR 1.70; 95%CI 1.16-2.49; p = 0.006). Median PFS, OS and MSS are shown in Table 1. After adjustment for potential confounders, patients treated with steroids + second-line immunosuppressants showed a non-significant trend towards a higher risk of progression (HRadj 1.40; 95%CI 1.00-1.97; p = 0.05), a higher risk of death (HRadj 1.54; 95%CI 1.03-2.30; p = 0.04) and of melanoma-specific death (HRadj 1.62; 95%CI 1.04-2.51; p = 0.032) compared to the steroids group. Conclusions: Second-line immunosuppression for irAEs is associated with impaired PFS, OS, and MSS in advanced melanoma patients treated with first-line ipilimumab-nivolumab, irrespective of being anti-TNF or other second-line immunosuppressants. These findings stress the importance of assessing the effects of differential irAE management strategies, not only in melanoma but also in other tumor types. [Table: see text]

Hospital variation in cancer treatments and survival outcomes of advanced melanoma patients: Nationwide quality assurance in the Netherlands

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Background: The introduction of new systemic treatments for advanced melanoma has markedly changed the outcome of patients with metastatic melanoma. To assure high quality of care for patients treated in Dutch melanoma centers, hospital variation in treatment patterns and outcomes are evaluated in the Dutch Melanoma Treatment Registry. The aim of this study was to assess center variation in treatments and 2-year survival probabilities of patients diagnosed between 2013-2017 in the Netherlands. Methods: We selected patients diagnosed between 2013-2017 with unresectable stage IIIC or IV melanoma, registered in the Dutch Melanoma Treatment Registry. Centers’ performance on 2-year survival was compared by means of a multivariable Cox proportional hazards model with a random effect for center ID. Variation between centers was expressed by median hazard ratios. Therapy with BRAF/MEK inhibitors, anti-PD-1 antibodies or ipilimumab plus nivolumab was added to the Cox proportional hazards model as a time dependent covariate to assess the influence of new systemic therapies on center variation. Results: Between 2013-2017, 3820 patients were diagnosed with unresectable stage IIIC or IV melanoma. For patients diagnosed between 2013-2015, significant center variation in 2-year survival probabilities was observed. Median hazard ratio was 1.17 (95%CI: 1.09-1.31) for patients diagnosed between 2013-2015 after correcting for case-mix and treatment with BRAF/MEK inhibitors, anti-PD-1 antibodies or ipilimumab plus nivolumab. Use of new systemic therapies had a significant effect on up to 2-year survival (hazard ratio = 0.83, 95%CI (0.73-0.94)) with no use of the new systemic therapies as a reference. From 2016 onwards, no significant difference in 2-years survival was observed between centers. Conclusions: The different use of new cancer treatment of metastatic melanoma had an effect on survival outcomes in the Netherlands. A platform such as the Dutch Melanoma Treatment Registry, in which melanoma centers collaborate and have insight in variation in treatment patterns and outcomes between centers, results in fast implementation of new clinical developments across all Dutch melanoma centers.

Is adjuvant treatment for melanoma in clinical practice comparable to trials? The first population-based results

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Background: Little is known about the outcome of adjuvant therapy in melanoma patients beyond the clinical trial setting. The Dutch Melanoma treatment Registry (DMTR) is a population-based registry, set up in July 2013 to monitor the safety and quality of melanoma care. Since 2019, adjuvant treated melanoma patients have also been registered in the DMTR, following approval and reimbursement of adjuvant treatment in the Netherlands in December 2018. Methods: Analyses were performed on melanoma patients treated with adjuvant anti-PD1 therapy included in the DMTR between 01-07-2018 and 31-12-2019. Descriptive statistics were used to analyze patient-, and treatment characteristics, and death as well as relapse rates. Results: Six hundred and fifty-seven patients treated with adjuvant systemic therapy were included in the DMTR. The majority (94%) of these patients was treated with anti-PD1. Twenty percent of the anti-PD1-treated patients developed grade ≥3 toxicity. Of the 279 patients with a minimum follow-up of one year after start of anti-PD1, 170 (61%) prematurely discontinued therapy. Relapse and death occurred in respectively, 38% and 12% of patients within one year of follow-up. Relapse was significantly more frequent in older patients, with high Breslow thickness and ulcerated melanomas. Conclusions: These data show more frequent premature discontinuation of adjuvant anti-PD1 in daily clinical practice than reported in the registration trials. Moreover, incidence of severe toxicity, relapse and death during adjuvant treatment appears higher in the real-world setting.

The prognostic value of the interferon-gamma (IFNγ) signature in patients with macroscopic stage III melanoma treated with and without adjuvant systemic therapy

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Background: Recently, trials have shown the benefit of adjuvant aPD-1 therapy in macroscopic stage III melanoma patients. This treatment has been incorporated in daily clinical practice, however, a substantial part of patients still does not benefit from this therapy, as they develop recurrences. The aim of this study is to evaluate the results of adjuvant aPD-1 therapy and the potency of the IFNγ signature as a prognostic or predictive marker, as it has proven to be predictive of response in neoadjuvant trials. Methods: Patients participating in an ongoing biobank study and naïve for systemic therapy were included, between 10-2017 and 06-2020, after complete resection of macroscopic stage III melanoma. Approval and reimbursement of adjuvant therapy in the Netherlands started in 12-2018, resulting in 2 cohorts of similar high risk patients: prior to availability of adjuvant aPD-1 (cohort A) and thereafter (cohort B). Data cut-off for clinical data was January 1st 2021. Transcriptome sequencing was performed on samples of stage III melanoma by CeGaT GmbH, IFNγ signature was determined on these data with the median as cut-off. Clinical data were compared between cohort A and B as intention-to-treat population, including patients with a recurrence before adjuvant therapy start (n=10). Results: In total, 99 patients were included: 50 in cohort A and 49 in cohort B. Majority of included patients had thick primary melanomas (Breslow >2mm in 59.6%) and stage IIIC/IIID disease (83.3%) according to AJCC 8th edition. At a median follow-up of 20.6 months (95% confidence interval [CI] 16.6-24.7), median recurrence-free survival (RFS) was 6.1 months (95%CI 3.9-8.4) versus 22.8 months (95%CI 8.7-36.9), significantly in favor of cohort B (p=0.011). Median overall survival (OS) was not reached in both patient groups, but was overall significantly different (p=0.040), favoring cohort B. RNA sequencing was performed in 25 patients who received adjuvant therapy and in 24 who did not, excluding patients with an early recurrence (<12 weeks). In both treatment groups median (p=0.003) and 12-months RFS (p<0.001) was significantly higher for IFNγ high patients, but both IFNγ low and high patients show higher RFS rates when receiving adjuvant aPD-1 therapy (Table). Conclusions: Our study confirms RFS and OS benefit of adjuvant aPD-1 for patients with macroscopic stage III melanoma. IFNγ has shown to be a prognostic marker in both patients who were and were not treated with adjuvant therapy, as both patients with IFNγ high and low signatures show benefit from adjuvant therapy.[Table: see text]

Efficacy of checkpoint inhibition in advanced acral melanoma

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Background: Recent data in Japanese patients suggest poor outcomes for anti-PD1 in acral melanoma (AM), with no data available on combination treatment. The objective of this study was to analyze the efficacy of anti-PD1 monotherapy and anti-PD1 and anti-CTLA4 combination therapy in these patients. Methods: Our study population consisted of patients registered in the nationwide prospective Dutch Melanoma Treatment Registry between 2014 and 2020. We calculated objective response rate (ORR) in all unresectable stage III and IV AM and nonacral cutaneous melanoma (NAM) patients treated with anti-PD1, and combination anti-PD1 and anti-CTLA4. Progression-free survival (PFS), and overall survival (OS) were estimated for first-line treated patients. A Cox proportional hazard analysis was performed to adjust for potential confounders. Results: Nighty-five AM patients received at least one dose of anti-PD1 monotherapy, of whom 58 (61%) as first-line treatment. ORR was 28% (complete response 11%; partial response 18%). Median PFS and OS in patients with first-line treatment were 5.5 months (95% CI 3.5-8.4) and 14 months (95% CI 9.3-25.0). In patients with NAM (n = 1259) ORR was 48% (complete response 18%; partial response 31%). Six-hundred and eighty-eight (55%) patients received anti-PD1 as first-line treatment. Median PFS was 11.7 months (95% CI 9.1-14.9) and median OS was 24 months (95% CI 20.0-29.3) in these patients. Older age, higher ECOG scores, elevated LDH levels, liver metastasis and brain metastasis were significantly associated with lower OS. After adjustment for covariates, acral subtype remained associated with shorter PFS (Hazard Ratio 1.76, 95% CI 1.25-2.48) and OS (Hazard Ratio 1.70, 95% CI 1.17-2.45). Twenty-four AM patients received at least one dose of anti-PD1 plus anti-CTLA4, of which 15 as first-line treatment. ORR was 25% (complete response 4%; partial response 20%). AM patients treated with first-line combination therapy had a median PFS of 3.8 months (95% CI 2.8-NR) and median OS of 7.63 months (95% CI 6.12-NR). ORR in NAM patients treated with combination therapy (n = 599) was 41% (complete response 8%; partial response 33%). Forty-six percent of these patients were treated in the first-line, with a median PFS of 9.7 months (95% CI 6.6-17.1) and median OS of 21.3 months (95% CI 14.6-36.5). Elevated LDH levels and the presence of BRAF mutation were significantly associated with lower OS. No significant association was found between acral subtype and PFS, or OS after adjustment for covariates. Conclusions: This study shows limited efficacy of anti-PD1 for advanced AM, with clinically relevant lower response rates compared to nonacral melanoma types. Although caution is needed because of relatively small numbers and the observational nature of our study, our data confirm limited efficacy of checkpoint inhibition in AM.

BRAF and NRAS mutation status and response to checkpoint inhibition in advanced melanoma

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Background: The ability to analyze tumor mutation profiles has altered the oncology treatment landscape over the past decades. However, little is known about the effect of specific gene mutations on the response to immune checkpoint inhibitors (ICIs) in patients with advanced melanoma. Methods: All unresectable stage IIIc and IV patients with BRAF V600, NRAS mutations and BRAF and NRAS wild-type patients treated with anti-PD-1 or ipilimumab-nivolumab between 2012 and 2020 were included from the Dutch Melanoma Treatment Registry, a nationwide population-based registry. Outcomes were objective response rate (ORR), progression-free survival (PFS), and overall survival (OS). A Cox model was used to analyze the association of possible prognostic factors with PFS and OS. Results: In total 1358 first-line patients treated with anti-PD-1 and 524 treated with ipilimumab-nivolumab were included. Median follow-up was 25.6 months for anti-PD-1 treated patients and 16.3 months for ipilimumab-nivolumab treated patients. The highest ORR, in first-line, to anti-PD-1 was in patients who were BRAF and NRAS wildtype (50.2%), compared to BRAF V600 (43.8%) and NRAS mutated patients (49.8%). ORR to ipilimumab-nivolumab was highest in NRAS mutated patients (44.9%), while ORR was 39.5% for BRAF mutated patients and 40.3% for wild-type patients. Median PFS in the anti-PD-1 treatment regimen was significantly higher (p = 0.049) for double wild-type patients (16.7 months) patients than for BRAF mutated patients (9.9 months) and NRAS mutated patients (11.3 months). PFS was not significantly different (p = 0.11) in the ipilimumab-nivolumab treatment cohort, with a median PFS of 6.5 months for the wild-type group, 10.8 months for the BRAF group, and 9.1 months for the NRAS group. In the anti-PD-1 treated patients, median OS was significantly higher (p < 0.001) for BRAF mutated patients (32.8 months) compared to NRAS (21.0 months) and wild-type patients (23.0 months). For ipilimumab-nivolumab treated patients, median OS was also significantly higher (p < 0.001) for BRAF mutated patients (36.5 months) than for NRAS mutated patients (11.8 months) and wild-type patients (16.1 months). After adjustment for potential confounders, the presence of a BRAF mutation remained associated with lower PFS in the anti-PD-1 treatment cohort and better OS in both treatment cohorts. Higher age, higher ECOG score, elevated LDH levels, liver metastases and brain metastases were associated with worse survival. Conclusions: PFS in first-line PD-1 was significantly higher for double wild-type patients than for BRAF mutant and NRAS mutant patients. PFS in ipilimumab-nivolumab treated patients did not significantly differ between BRAF mutant, NRAS mutant and double wild-type patients. OS was significantly higher for BRAF mutant patients in both treatment strata, which is probably the result of the subsequent BRAF/MEK-inhibition treatment option in this group.

Dutch advanced melanoma care in times of COVID-19

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Background: The COVID-19 pandemic COVID had a severe impact on medical care in The Netherlands. So far, few studies have investigated the influence of COVID-19 on advanced melanoma care nationwide. This study aims to investigate the impact of COVID-19 on the systemic treatment of unresectable stage III and IV advanced melanoma patients in the Netherlands. Methods: Data were obtained from the Dutch Melanoma Treatment Registry (DMTR), a population-based nationwide registry of all stage III and IV melanoma patients amenable for systemic treatment. We compared two patient groups dependent on the date of the first diagnosis of metastasis: during the first COVID-19 wave (March 15th 2020 until May 22nd 2020), and a control group during the same period one year earlier. Furthermore, we divided patients into three geographical regions within the Netherlands (north, middle and south). These regions were based on the maximum number of hospital admissions for COVID-19 patients during the first wave, using data from the National Intensive Care Evaluation (NICE). COVID-19 incidence was highest in the southern part of The Netherlands. We investigated baseline characteristics, type of systemic therapy, time from diagnosis of the irresectable stage III or IV melanoma until the start of systemic therapy, postponement of anti-PD-1 courses in patients actively being treated during the predefined time periods and progression-free survival (PFS) and overall survival (OS) using Kaplan-Meier estimates. Results: During the first COVID-19 wave, 104 patients were diagnosed with advanced melanoma versus 166 patients during the control period in 2019. No significant differences were found in patient and tumor characteristics, type of systemic therapies or in the time from diagnosis until the start of systemic therapy, between the different periods. However, during the first wave, the time between diagnosis until the start of treatment was significantly longer in the southern regions as compared to the northern and middle regions (33 vs 9 and 15 days, p-value < 0.05). Anti-PD-1 antibody treatment courses were postponed in 79 patients (15.5%) during the first wave versus four patients (1.1%) in the control period. Significantly more patients had a postponed course in the south during the first wave compared to the middle and northern regions (30.2% vs 2.7% vs 16.7%, p-value < 0.001). With limited follow-up, thus far no significant differences in PFS and OS were found. Conclusions: Advanced melanoma care in the Netherlands was severely affected by the COVID-19 pandemic. In the south, where COVID-19 incidence was highest in the first wave, the start of systemic treatment for advanced melanoma was more often delayed, and treatment courses were more frequently postponed. Longer follow-up is needed to establish whether this has had an impact on patient outcome.

Toxicity, response, and survival in older adults with metastatic melanoma treated with checkpoint inhibitors

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Background: Checkpoint inhibitors have strongly improved survival of patients with metastatic melanoma. Trials suggest no differences in outcomes between older and younger patients, but only relatively young patients with a good performance status were included in these trials. The aim of this study was to describe treatment patterns and outcomes of older adults with metastatic melanoma, and to identify predictors of outcome. Methods: We included all patients aged ≥65 years with metastatic melanoma between 2013 and 2020 from the Dutch Melanoma Treatment registry (DMTR), in which detailed information on patients, treatments and outcomes is available. We assessed predictors of grade ≥3 toxicity and 6-months response using logistic regression models, and melanoma-specific and overall survival using Cox regression models. Additionally, we described reasons for hospital admissions and treatment discontinuation. Results: A total of 2216 patients were included. Grade ≥3 toxicity did not increase with age, comorbidity or WHO performance status, in patients treated with monotherapy (anti-PD1 or ipilimumab) or combination treatment. However, patients aged ≥75 were admitted more frequently and discontinued treatment due to toxicity more often. Six months-response rates were similar to previous randomized trials (40.3% and 43.6% in patients aged 65-75 and ≥75 respectively for anti-PD1 treatment) and were not affected by age or comorbidity. Melanoma-specific survival was not affected by age or comorbidity, but age, comorbidity and WHO performance status were associated with overall survival in multivariate analyses. Conclusions: Toxicity, response and melanoma-specific survival were not associated with age or comorbidity status. Treatment with immunotherapy should therefore not be omitted solely based on age or comorbidity. However, the impact of grade I-II toxicity in older patients deserves further study as older patients discontinue treatment more frequently and receive less treatment cycles.[Table: see text]

Pathological response and tumour bed histopathological features correlate with survival following neoadjuvant immunotherapy in stage III melanoma

BACKGROUND

Guidelines for pathological evaluation of neoadjuvant specimens and pathological response categories have been developed by the International Neoadjuvant Melanoma Consortium (INMC). As part of the Optimal Neo-adjuvant Combination Scheme of Ipilimumab and Nivolumab (OpACIN-neo) clinical trial of neoadjuvant combination anti-programmed cell death protein 1/anti-cytotoxic T-lymphocyte-associated protein 4 immunotherapy for stage III melanoma, we sought to determine interobserver reproducibility of INMC histopathological assessment principles, identify specific tumour bed histopathological features of immunotherapeutic response that correlated with recurrence and relapse-free survival (RFS) and evaluate proposed INMC pathological response categories for predicting recurrence and RFS.

PATIENTS AND METHODS

Clinicopathological characteristics of lymph node dissection specimens of 83 patients enrolled in the OpACIN-neo clinical trial were evaluated. Two methods of assessing histological features of immunotherapeutic response were evaluated: the previously described immune-related pathologic response (irPR) score and our novel immunotherapeutic response score (ITRS). For a subset of cases (n = 29), cellular composition of the tumour bed was analysed by flow cytometry.

RESULTS

There was strong interobserver reproducibility in assessment of pathological response (κ = 0.879) and percentage residual viable melanoma (intraclass correlation coefficient = 0.965). The immunotherapeutic response subtype with high fibrosis had the strongest association with lack of recurrence (P = 0.008) and prolonged RFS (P = 0.019). Amongst patients with criteria for pathological non-response (pNR, >50% viable tumour), all who recurred had ≥70% viable melanoma. Higher ITRS and irPR scores correlated with lack of recurrence in the entire cohort (P = 0.002 and P ≤ 0.0001). The number of B lymphocytes was significantly increased in patients with a high fibrosis subtype of treatment response (P = 0.046).

CONCLUSIONS

There is strong reproducibility for assessment of pathological response using INMC criteria. Immunotherapeutic response of fibrosis subtype correlated with improved RFS, and may represent a biomarker. Potential B-cell contribution to fibrosis development warrants further study. Reclassification of pNR to a threshold of ≥70% viable melanoma and incorporating additional criteria of <10% fibrosis subtype of response may identify those at highest risk of recurrence, but requires validation.

Clinical auditing as an instrument to improve care for patients with ovarian cancer: The Dutch Gynecological Oncology Audit (DGOA)

INTRODUCTION

The Dutch Gynecological Oncology Audit (DGOA) was initiated in 2014 to serve as a nationwide audit, which registers the four most prevalent gynecological malignancies. This study presents the first results of clinical auditing for ovarian cancer in the Netherlands.

METHODS

The Dutch Gynecological Oncology Audit is facilitated by the Dutch Institute of Clinical Auditing (DICA) and run by a scientific committee. Items are collected through a web-based registration based on a set of predefined quality indicators. Results of quality indicators are shown, and benchmarked information is given back to the user. Data verification was done in 2016.

RESULTS

Between January 01, 2014 and December 31, 2018, 6535 patients with ovarian cancer were registered. The case ascertainment was 98.3% in 2016. The number of patients with ovarian cancer who start therapy within 28 days decreased over time from 68.7% in 2014 to 62.7% in 2018 (p < 0.001). The percentage of patients with primary cytoreductive surgery decreased over time (57.8%-39.7%, P < 0.001). However, patients with complete primary cytoreductive surgery improved over time (53.5%-69.1%, P < 0.001). Other quality indicators did not significantly change over time.

CONCLUSION

The Dutch Gynecological Oncology Audit provides valuable data on the quality of care on patients with ovarian cancer in the Netherlands. Data show variation between hospitals with regard to pre-determined quality indicators. Results of 'best practices' will be shared with all participants of the clinical audit with the aim of improving quality of care nationwide.

The value of lymph node ultrasound and whole body PET/CT in stage IIB/C patients prior to SLNB

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Background: Stage IIB/IIC (pT3b-T4N0) patients are known to have high-risk primary tumors, even higher risk than some stage IIIA/B melanomas (AJCC Staging System 8th edition), however they follow the same routine to sentinel lymph node biopsy (SLNB) as more low-risk tumors. A priori the risk of finding SLNB or other metastases is much higher for these thick and/or ulcerated primary melanomas compared to the thinner ones. Guidelines are not conclusive regarding the use of preoperative imaging in these cases. Recently, a trend to more frequently use cross-sectional imaging has been noticed. However, others have previously shown that preoperative ultrasound was the most sensitive. The aim of this pilot study was to assess the value of ultrasound (US) and Positron Emission Tomography/Computerized Tomography (PET/CT) prior to SLNB for stage IIB/C (pT3b-T4N0) melanoma patients. Methods: Starting 2019-04, all patients with a pT3b melanoma or higher (8th AJCC) were included. All patients underwent US and PET/CT before their planned lymphoscintigraphy and routine SLNB. Suspected metastases were confirmed with cytologic puncture. Results: A total of 20 patients were screened. Seven patients (35%) had metastases detected by imaging: one by PET/CT, three by US and three by both imaging modalities. Three of these metastases were detected by US as well as PET/CT. All metastases were nodal. For all seven patients treatment was altered to lymph node dissection with adjuvant therapy. Of the 13 patients in whom no metastases were identified by imaging, six (46%) still had a positive sentinel node (SN). Conclusions: This study showed that this select group of patients had a high risk of metastases prior to SLNB and that all recurrences except one, were detected by ultrasound. This suggests that nodal staging with US is sufficient and can replace the need for SLNB when metastases is proven with cytology. Despite negative imaging, SLNB cannot be foregone for pT3b-pT4N0 melanoma patients, as many still have an involved SN. Cross-sectional imaging can be reserved for patients after positive cytology or SN to confirm the absence of distant visceral metastases.

The use of PET/CT to detect early recurrence after resection of high-risk stage III melanoma, prior to the start of adjuvant therapy and during follow-up

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Background: To date, international consensus concerning the use of PET/CT as a surveillance tool in the follow-up of high-risk melanoma patients after complete resection of disease is lacking. Moreover, with the rise of adjuvant therapy it seems appropriate to investigate the role of this imaging modality to exclude newly developed metastases after resection and prior to starting treatment. The aim of this study was to investigate the use of PET/CT as surveillance tool in the follow-up and prior to adjuvant therapy in asymptomatic patients with complete resection of stage IIIB and IIIC melanoma. Methods: Prospectively two cohorts were set up with stage III melanoma patients with complete resection of disease. In the first cohort (stage IIIB/C AJCC 7th) surveillance PET/CT was performed 6-monthly for two years if patients stayed asymptomatic with normal serum S100B, with a final scan at three years. In the second cohort (stage IIIB/C/D AJCC 8th) patients underwent one screening PET/CT after resection and prior to starting adjuvant treatment. Results: Eighty patients entered follow-up in cohort 1. Of these, the majority did not undergo surveillance scans, because they required treatment for newly detected clinical metastases. Thirty-five patients remained asymptomatic and were included in surveillance cohort one (105 scans) with a median follow-up of 33 months. Twelve patients (34%) developed a recurrence, seven (20%) of which were detected on the first scan at six months. Seven recurrences involved stage IIIC patients, five stage IIIB patients. Sensitivity and specificity were 92% and 100% respectively. Forty-two patients were included in cohort 2. Recurrence was suspected on nine scans, four (10%) of which were true positive. One patient proceeded to undergo a node dissection and then started adjuvant therapy. The other three patients had progressed to stage IV and therefore started radiotherapy and/or systemic immunotherapy. Five (12%) scans were false positive, the suspected lesions were not related to the preceded surgery. The number of scans needed to find one asymptomatic recurrence were 8.8 and 10.5 in cohort one and two, respectively. Conclusions: This study shows that PET/CT is a useful surveillance tool for detecting recurrence in asymptomatic high-risk resected stage III melanoma patients, especially within the first six months after surgery and therefore should be considered when monitoring these patients during follow-up as well as prior to starting adjuvant therapy.

Real-world outcomes of advanced melanoma patients not represented in phase III trials

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Background: A large proportion of patients with advanced melanoma is not represented in phase III clinical trials, due to ineligibility. Real-world efficacy evidence of immune- and targeted therapies in these patients is lacking. We aimed to provide insight in survival outcomes of systemically treated patients who were not represented in the phase III trials in order to support clinical decision-making. Methods: Systemically treated ineligible patients with advanced melanoma diagnosed between 2014-2017 were analyzed. Prognostic importance of factors associated with overall survival (OS) was assessed by Kaplan Meier method, Cox regression models, predicted OS probabilities of prognostic subgroups and a conditional inference survival (decision) tree. Results: Of 2,536 systemically treated patients with advanced melanoma, 1,004 (40%) patients were ineligible for phase IIII trials. Ineligible patients had a poorer median OS (mOS) compared to eligible patients (8.8 vs 23 months). Eligibility criteria most strongly correlated with survival in ineligible systemically treated patients with ECOG Performance Score (PS) ≥2 vs PS 0-1 (HR 1.95 (95%CI: 1.52-2.5)), symptomatic brain metastases (BM) vs absent BM (HR 1.71 (95%CI: 1.34-2.18)) and LDH > 500 U/l vs normal (HR 1.89 (95%CI: 1.49-2.41)). All other factors for ineligibility were not associated with OS. By combining ECOG PS, BM and LDH, 18 subgroups were created. The 3-year survival probability of patients with ECOG PS ≤1, asymptomatic BM and normal LDH was 35.1%. Patients with ECOG PS of ≥2 with or without symptomatic BM had a mOS of 6.5 and 11.3 months and a 3-year survival probability of 9.3% and 23.6% respectively. In the decision tree, the covariate with the strongest predictive distinctive character for survival was LDH, followed by ECOG PS. Prognosis of LDH of > 500 U/L is infaust, although still long-term survival is possible (3-year survival probability of 15.3%). The decision tree showed the prognosis of patients with symptomatic BM can be good if ECOG PS is 0 and patients are aged ≤55 years (mOS of 22.3 months). Conclusions: Patients with advanced melanoma not represented in phase III trials treated with systemic therapy can achieve long term survival. LDH was the strongest predictive factor associated with survival, followed by ECOG PS and symptomatic BM. Other factors for ineligibility were not associated with OS. These results, together with the decision tree, can be used to provide insight in outcomes to facilitate the shared decision-making process when comparative studies are not available.

Rate of complete and durable responses of intralesional therapy with talimogene laherparepvec for stage IIIB-IVM1a melanoma and association with tumor load

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Background: Talimogene laherparepvec (T-VEC) is a genetically modified herpes simplex type 1 virus, which is used as an oncolytic immunotherapy in stage IIIB-IVM1a melanoma patients. It is known to be an effective therapy for injectable cutaneous, subcutaneous and nodal melanoma lesions, as approved by the European Medicines Agency (EMA). Combination therapy is not yet approved by EMA pending the results of the phase 3 Masterkey-265 trial. The objective of the current study was to identify prognostic factors for achieving a complete response (CR) that can be used to select patients for treatment with T-VEC monotherapy. Methods: Patients with stage IIIB-IVM1a melanoma, treated with T-VEC at the Netherlands Cancer Institute between 2016-12 and 2019-05 with a follow-up time > 6 months, were included. Data was collected on baseline characteristics, responses and adverse events (AEs). Durable response rate (DRR) was defined as the percent of patients with a CR or partial response (PR) maintained continuously > 6 months. Univariable analyses were conducted and a prediction model was developed to identify prognostic factors associated with complete response. Results: For this study, a total of 71 patients were included with a median follow-up of 16.1 months. The median age was 70 years (range: 35-90). As best response, 47 patients (66%) had a CR and 10 patients (14%) had a PR, resulting in an overall response rate of 80%. Twenty-one patients (30%) stopped treatment because of progressive disease and sixteen patients (23%) developed a recurrence during follow-up after achieving a PR or CR. Median duration of CR was 11 months. The durable response rate was 42%. Grade 1-2 AEs occurred in almost every patient. Tumor size, type of metastases, previous treatment with systemic therapy and stage (8Th AJCC) were independent prognostic factors for achieving a CR and for progression-free survival. Achieving a CR was associated with a reduced risk of death. The prediction model includes tumor size, type of metastases (only cutaneous vs. subcutaneous (+/- cutaneous) vs. nodal (+/- cutaneous/subcutaneous)) and number of lesions as predictors. Conclusions: This study shows that intralesional T-VEC monotherapy for stage IIIB-IVM1a melanoma is able to achieve high complete and durable response rates. The prediction model shows that use of T-VEC in patients with less tumor burden is associated with better outcomes, suggesting T-VEC should perhaps be used earlier in the course of the disease.

Surgery for unresectable stage IIIC and IV melanoma in the era of new systemic therapy

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Background: Over the past decade opportunities for surgical treatment in metastatic melanoma patients have re-emerged due to the development of novel systemic therapies. However, selecting patients who will benefit from surgery after systemic therapy is still difficult. The aim of this study is to present data on outcomes of surgery in patients with unresectable stage III and IV melanoma, who have previously been treated with immune checkpoint inhibitors (ICI) or targeted therapy, to provide insight in which patients may benefit from surgery. Methods: Data was extracted from the prospectively collected, nationwide, Dutch Melanoma Treatment Registry (DMTR) onunresectable stage IIIC or advanced/metastatic stage IV melanomapatients who obtained disease control with systemic therapy and underwent subsequent surgery. Disease control was defined as a complete response (CR), partial response (PR) or stable disease (SD). After disease control was achieved with systemic therapy, progressive disease (PD) was allowed as a most recent status of disease prior to surgery, to avoid excluding patients with oligoprogression. Major exclusion criteria were non-cutaneous melanoma and brain metastases. Results: Of 3959 patients in the DMTR database, 154 patients met our inclusion criteria. Of these patients, 79 (51%) were treated with ICI, 61 (40%) with targeted therapy and 9.1% with study or other treatments before surgery. The best response to systemic therapy was a CR in 5.2%, PR in 46.1% and SD in 44.2% of patients. At a median follow-up of 10.0 months (IQR 4-22) after surgery, the median overall survival (OS) had not been reached in our cohort and median progression free survival (PFS) was 9.0 months (95% CI 6.3-11.7). A multivariate cox regression analysis showed that when surgery led to CR or PR, the PFS and OS were better than if surgery led to SD or PD (p < 001). Also, ICI seemed to be more favorable than targeted therapy in both PFS (median of 15 versus 7 months) and OS (median not reached versus 32 months) (p = 0.026 and p = 0.003). Conclusions: We conclude that selected unresectable stage IIIC or stage IV melanoma patients might benefit from surgery after achieving disease control with systemic therapy. Expected residual tumor after surgery could be an important selection criterion. Especially patients undergoing surgery after initial tumor response on ICI have a chance of long-term survival.

Health-related quality of life in stage III melanoma patients treated with neoadjuvant ipilimumab and nivolumab followed by index lymph node excision only, compared to therapeutic lymph node dissection: First results of the PRADO trial

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Background: Neoadjuvant ipilimumab and nivolumab induces high pathologic response rates of 74-78% (OpACIN and OpACIN-neo trial), thus the role of Therapeutic Lymph Node Dissections (TLND) in patients with major pathologic responses (MPR: pathological (near) complete response) is now unclear. In the PRADO trial, TLND was omitted in patients with MPR in their index lymph node ((ILN), the largest LN marked prior to neoadjuvant therapy). We sought to determine if less extensive surgery is associated with better Health Related Quality of Life (HRQoL). These are the first results of the comparison of HRQoL between patients undergoing a TLND or less extensive ILN excision. Methods: HRQoL was assessed with the European Organisation for Research and Treatment of Cancer QoL questionnaire-C30 (QLQ-C30). A generalized estimation equation was used to assess the difference in HRQoL outcomes between patients who underwent TLND (pathological non- and partial-responders, pNR/pPR) versus those who did not (pathological (near)complete responders, pNCR/pCR). Differences were adjusted for age, gender and follow-up (FU, in weeks), but not for pathological responses (pNR, pPR, pNCR & pCR). Differences in QLQ-C30 scores were classified as clinically important according to published guidelines. Results: A total of 49 patients from the PRADO study had reached at least 24 weeks FU, and were included in the first explorative analysis. The median age of this study population was 58 years (range, 22-84). Questionnaire completion rates were high: 94% at baseline, 100%, 90%, 88% at week 6, 12 and 24, respectively. Sixteen (33%) patients underwent TLND versus 33 (67%) who had ILN excision only. Over a FU period of 24 weeks, patients who underwent TLND scored significantly lower on global (68 vs 78, adjusted difference (diff) = -9.53, p = .005), physical (84 vs 94 diff = -11.1, p = < .001), emotional (69 vs 83, diff = -11.7, p = .001), role (70 vs 85, diff = -13, p = .004), and social functioning (81 vs 91, diff = -8.9, p = .016) and had a higher symptom burden of fatigue (35 vs 23, diff = 11.1, p = .004), insomnia (38 vs 18, diff = 16.6, p = .002) and financial impact (12 vs 4, diff = 7.9, p = .027) than patients undergoing ILN excision only. These differences were indicated as clinically relevant. Conclusions: First results from PRADO suggest that reducing the extent of surgery following neoadjuvant immunotherapy might result in better HRQoL of high-risk stage III melanoma patients. Clinical trial information: NCT02977052.

Switching to Immune Checkpoint Inhibitors upon Response to Targeted Therapy; The Road to Long-Term Survival in Advanced Melanoma Patients with Highly Elevated Serum LDH?

The prognosis of patients with advanced melanoma has improved dramatically. However, the clinical outcomes of patients with highly elevated serum lactate dehydrogenase (LDH) remain very poor. The aim of this study was to explore whether patients with normalized LDH after targeted therapy could benefit from subsequent treatment with immune checkpoint inhibitors (ICI). Data from all patients with BRAF-mutant metastatic melanoma with a highly elevated serum LDH at baseline (≥2× upper limit of normal) receiving first-line targeted therapy between 2012 and 2019 in the Netherlands were collected. Patients were stratified according to response status to targeted therapy and change in LDH at start of subsequent treatment with ICI. Differences in overall survival (OS) between the subgroups were compared using log-rank tests. After a median follow-up of 35.1 months, median OS of the total study population (n = 360) was 4.9 months (95% CI 4.4-5.4). Of all patients receiving subsequent treatment with ICI (n = 113), survival from start of subsequent treatment was significantly longer in patients who had normalized LDH and were still responding to targeted therapy compared to those with LDH that remained elevated (median OS 24.7 vs. 1.1 months). Our study suggests that introducing ICI upon response to targeted therapy with normalization of LDH could be an effective strategy in obtaining long-term survival in advanced melanoma patients with initial highly elevated serum LDH.

Challenges in sentinel node (SN) pathology in the era of adjuvant treatment: The risk of over and undertreatment stress the need for expert pathology review

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Background: With the approval of adjuvant therapy for stage III melanoma, accurate staging in melanoma patients is important more than ever to prevent over- or undertreatment. Sentinel node biopsy (SNB) is an accurate staging tool, yet the presence of capsular nevi (CN) can lead to a false positive diagnosis. We compared positive SNB and CN patient outcomes and aimed to evaluate the cause of false positive SNB and discern diagnostic pitfalls in their evaluation. Methods: Retrospective analysis of AJCC 7th Edition stage IIIA melanoma patients (N1-2a, non-ulcerated primary tumor) who were treated at our institute between 2000 and 2015. SNB slides were reviewed for this study by an expert melanoma pathologist. Baseline characteristics were assessed for SN+ and CN+ patients. Concordance rates for SNB evaluation before and after revision were documented and diagnostic pitfalls were discerned. Results: 169 patients were diagnosed, 10 could not be reviewed due to lack of evaluable slides. Of these 159 cases, 14 patients originally diagnosed with metastatic melanoma were shown to have capsular nevi (8.8%). Another 2 patients were shown to have melanophages that were incorrectly interpreted as metastases (1.3%). Thus, 10.1% was considered false positive after revision. In 14 patients the SN tumor burden was originally reported > 1 mm, but turned out to have < 1 mm SN tumor burden. 4 patients originally reported as SN tumor burden < 1 mm before revision turned out to have > 1 mm SN tumor burden. These 32 patients (20%) might have potentially been over- or undertreated in the current era of adjuvant therapy for stage III melanoma. Conclusions: False positive sentinel node results in melanoma are real, they can occur for a number of reasons, but distinguishing metastatic melanoma from benign capsular nevi and melanophages can be a diagnostic challenge. We plead for an expert pathologists’ review in any case, but certainly when using the SNB+ results to determine treatment consequences for SN+ melanoma patients.

Surgical removal of the index node marked using magnetic seed localization to assess response to neoadjuvant immunotherapy in patients with stage III melanoma

This pilot study explored the value of localized index node removal after neoadjuvant immunotherapy in patients with stage III melanoma, for use as a response indicator to guide the extent of completion lymph node dissection. Promising technology.

Efficacy and safety of isolated limb perfusion for melanoma in elderly patients

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Background: Data on isolated limb perfusion (ILP) in elderly melanoma patients is scarce. We aimed to evaluate the efficacy and safety of ILP in our institutional cohort of melanoma patients. Methods: Retrospective analysis of AJCC stage IIIB/C melanoma patients who underwent ILP for locally advanced (unresectable) melanoma in-transit metastases of the limb between 2000 and 2016. Normothermic ILP (37-38 °C) was performed with either Melphalan or Melphalan and Tumor Necrosis Factor (TNF). Baseline characteristics, local toxicity (Wieberdink) and systemic toxicity, locoregional progression-free survival (PFS) and melanoma-specific survival (MSS) were assessed and prognostic factors for response to ILP, melanoma recurrence and survival were analyzed using univariable and multivariable analysis. Results: 88 patients were included. The overall response rate to ILP was 81%, with a complete response (CR) rate of 47%. Median overall locoregional PFS was 6 months, while patients with a CR had a median PFS of 16 months. Median overall MSS was 38 months. Two patients (2.3%) suffered Wieberdink IV toxicity (compartment syndrome), while no patients required amputation because of severe toxicity. Based on the median age of 70, we split patients into younger and elderly groups. Toxicity rates, response rates and locoregional PFS did not differ significantly between younger and elderly patients. CR was prognostic for improved locoregional PFS and MSS. Moreover, patients > 70 and patients with stage IIIC disease had a higher risk of melanoma-specific death. Conclusions: ILP has good and potential durable responses, but also less frequent and less severe toxicity than recently developed targeted or immune therapies, which can be reserved for progression to stage IV. This study showed that ILP is an effective and safe procedure for elderly patients ( > 70) with locally advanced melanoma of the limb.

Variation in head and neck cancer care in the Netherlands: A retrospective cohort evaluation of incidence, treatment and outcome

BACKGROUND

To explore variation in numbers and treatment between hospitals that treat head and neck cancer (HNC) in the Netherlands.

MATERIAL AND METHODS

Patient, tumor and treatment characteristics were collected from the Netherlands Cancer Registry, while histopathological features were obtained by linkage to the national pathology record register PALGA. Inter-hospital variation in volume, stage, treatment, pathologically confirmed loco-regional recurrence and overall survival rate was evaluated by tumor site.

RESULTS

In total, 2094 newly diagnosed patients were included, ranging from 65 to 417 patients in participating hospitals treating HNC in 2008. Oral cavity cancer was mainly treated by surgery only, ranging from 46 to 82% per hospital, while the proportion of surgery with (chemo)radiotherapy ranged from 18 to 40%. Increasing age, male sex, and high stage were associated with a higher hazard of dying. In oropharynx cancer, the use of (chemo)radiotherapy varied from 31 to 82% between hospitals. We found an indication that higher volume was associated with a lower overall hazard of dying for the total group, but not by subsite. Low numbers, e.g. for salivary gland, nasopharynx, nasal cavity and paranasal sinus, did not permit all desired analyses.

CONCLUSION

This study revealed significant interhospital variation in numbers and treatment of especially oropharyngeal and oral cavity cancer. This study is limited because we had to rely on data recorded in the past for a different purpose. To understand whether this variation is unwanted, future research should be based on prospectively collected data, including detailed information on recurrences, additional case-mix information and cause of death.

The Dutch Upper GI Cancer Audit: 2011-2014

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Background: In 2011, the Dutch Upper GI Cancer Audit (DUCA) group started with a nationwide registration of all patients who underwent surgery for esophageal or gastric cancer. The aim of this study was to describe the initiation and implementation of the DUCA and to provide an overview of the results. Methods: The DUCA is part of the Dutch Institute for Clinical Auditing. It provides (surgical) teams with reliable, weekly updated, benchmarked information on process and (casemix-adjusted) outcome measures. A web-based registration was designed, based on a set of predefined quality measures. Results: Between 2011 and 2014, a total of 4672 patients with esophageal or gastric cancer was registered in the DUCA. Case ascertainment has approached 100% for patients registered in 2014. The percentage of patients with esophageal cancer starting treatment within 5 weeks after diagnosis significantly increased over time (33 to 41%) and the percentage of patients with a minimum of 15 lymph nodes in the resected specimen significantly increased for both esophageal cancer (50 to 73%) and gastric cancer (48 to 74%). Postoperative mortality decreased for patients with gastric cancer (8.0% in 2011 to 4.0% in 2014; p = 0.020) and remained stable (around 4%) for patients with esophageal cancer. Conclusions: Nationwide implementation of the DUCA has been successful. Results give a valuable insight in the quality of the surgical care for patients with esophageal or gastric cancer and show a positive trend for various process and outcome measures.

The influence of a composite hospital volume of upper gastrointestinal cancer resections on outcomes of gastric cancer surgery

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Background: There is a known volume-outcome association for complex surgial procedures such as oncologic gastric resections. The aim of this study was to describe the process of centralization for gastric cancer surgery in the Netherlands in relation to other types of upper gastrointestinal (GI) cancer resections and to investigate whether the quality of gastric cancer surgery is affected by the overall experience with those related complex surgical procedures. Methods: Data on all patients (n = 4251) who underwent surgical treatment for non metastatic invasive gastric cancer between 2005-2013 were obtained from the Netherlands Cancer Registry. Annual hospital volume categories were based on the overall volume of gastrectomies, esophagectomies and pancreatectomies together (composite hospital volume). Volume-outcome analyses were performed for lymph node yield, 30-day mortality, and overall survival. Results: The percentage of gastric cancer patients who underwent a resection in a hospital with a volume of at least 20 gastrectomies per year increased. At the same time, the percentage of gastric cancer patients who underwent surgery in hospitals with an annual composite hospital volume of at least 20 upper GI cancer resections, such as esophageal and pancreatic cancer resections, increased. A higher composite hospital volume was associated with a higher lymph node yield, a lower 30-day mortality, and an increased overall survival. Conclusions: In the Netherlands, an increasing proportion of gastric cancer resections is performed in hospitals that are high volume centers for esophagectomies and pancreatectomies for cancer. Experience with these complex surgical procedures has a favorable effect on the outcomes of gastric cancer surgery.

Evaluation of an interactive portal for breast cancer survivors: Use, satisfaction, and preliminary effects

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Background: MijnAVL is an interactive portal that includes patient education, an overview of appointments, access to the electronic medical record (EMR), patient-reported outcomes plus feedback and physical activity support. The aim of this feasibility study was to evaluate use, satisfaction and preliminary effects among breast cancer survivors. Methods: We included women currently or recently treated for breast cancer with curative intent. At baseline, they completed a questionnaire on sociodemographics, expectations of MijnAVL and three effect measures: patient activation (PAM), quality of life (SF-36), and physical activity (IPAQ). MijnAVL could be used noncommittally for 4 months. Log data were collected retrospectively and participants completed questions on satisfaction and effect measures. This process was conducted twice, to be able to improve MijnAVL iteratively. Results: We included 92 women (mean age 49.5 years, 59% on-treatment). Mean number of logins was 8.7 and mean duration 13.1 minutes. Overview of appointments (80% of participants) and access to the EMR (90%) were most frequently used and most appreciated. Website user satisfaction was rated 3.8 on a 1-5 scale on average and participants were primarily positive about the accessibility of information. We did not find an effect on the PAM. For the SF-36, we found significant improvements on the role functioning – emotional (65.3 to 78.5, p< .01), mental health (69.8 to 76.5, p< .01) and social functioning (71.2 to 80.5, p< .01) domains. Median vigorous physical activity significantly increased from 0 to 360 MET-minutes per week (p< .05); levels of walking and moderate physical activity did not change significantly over time. These effects were not related to the intensity of use of MijnAVL. Conclusions: This study showed that user experiences were positive and that exposure to MijnAVL resulted in improvements on three quality of life domains and vigorous physical activity. More tailored, interactive features might be needed to substantially change empowerment, quality of life and physical activity. Research with a controlled design and possibly a more sensitive measure for patient empowerment are needed to substantiate our findings.

Feasibility and preliminary efficacy of an interactive portal for lung cancer patients

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Background: “MijnAVL” is an interactive portal for cancer patients that includes patient education, an overview of appointments, access to the electronic medical record, patient-reported outcomes and related feedback, and tailored physical activity support. The aim of this study was to evaluate MijnAVL’s feasibility and preliminary efficacy among lung cancer patients. Methods: We included individuals currently or recently treated for lung cancer with curative intent (surgery or radiotherapy). At baseline, they completed a questionnaire on sociodemographics, expectations of MijnAVL and three effect measures: patient activation (PAM), quality of life (SF-36), and physical activity (IPAQ). MijnAVL could be used noncommittally for 4 months. After this period, log data were collected retrospectively and participants completed questions on satisfaction and the effect measures. Results: We included 37 patients (mean age 59.6 years). The mean number of logins was 11.2 with a mean duration of 12.9 minutes. Eighty-nine percent of patients indicated that MijnAVL was easy to use and 82% was positive about using it. Many patients (69%) indicated that MijnAVL was a valuable addition to the care they received and 56% indicated that it helped them to have more control over their health. All features were frequently used and rated 7 or higher on a 10 point scale. Website user satisfaction was rated, on average, 3.9 on a 5 point scale. Patient activation decreased over time from 64.8 to 59.4 (p= 0.049), meaning patients felt less activated. For the SF-36, we found no significant changes over time. In general, levels of physical activity did not change, although vigorous physical activity tended to increase over time (from median of 0 to 360 MET-minutes per week (p= .053)). Conclusions: These results indicate that using MijnAVL is feasible in lung cancer patients. Most users indicated that MijnAVL was useful and easy to use. The efficacy of the patient portal could not be substantiated, which could be due to small sample size, the intervention itself, the (insensitivity of) outcome measures, or a combination of these. Further research is needed to find effective ways to improve and adequately measure patient empowerment in lung cancer survivors.

Comparing colon cancer outcomes: The impact of low hospital case volume and case-mix adjustment

OBJECTIVE

When comparing performance across hospitals it is essential to consider the noise caused by low hospital case volume and to perform adequate case-mix adjustment. We aimed to quantify the role of noise and case-mix adjustment on standardized postoperative mortality and anastomotic leakage (AL) rates.

METHODS

We studied 13,120 patients who underwent colon cancer resection in 85 Dutch hospitals. We addressed differences between hospitals in postoperative mortality and AL, using fixed (ignoring noise) and random effects (incorporating noise) logistic regression models with general and additional, disease specific, case-mix adjustment.

RESULTS

Adding disease specific variables improved the performance of the case-mix adjustment models for postoperative mortality (c-statistic increased from 0.77 to 0.81). The overall variation in standardized mortality ratios was similar, but some individual hospitals changed considerably. For the standardized AL rates the performance of the adjustment models was poor (c-statistic 0.59 and 0.60) and overall variation was small. Most of the observed variation between hospitals was actually noise.

CONCLUSION

Noise had a larger effect on hospital performance than extended case-mix adjustment, although some individual hospital outcome rates were affected by more detailed case-mix adjustment. To compare outcomes between hospitals it is crucial to consider noise due to low hospital case volume with a random effects model.

High complication rate after low anterior resection for mid and high rectal cancer; results of a population-based study

BACKGROUND

Surgical resection is the cornerstone of treatment for rectal cancer patients. Treatment options consist of a primary anastomosis, anastomosis with defunctioning stoma or end-colostomy with closure of the distal rectal stump. This study aimed to compare postoperative outcome of these three surgical options.

METHODS

Data was derived from the national database of the Dutch Surgical Colorectal Audit. Mid and high rectal cancer patients who underwent rectal cancer resection between January 2011 and December 2012 were included. Endpoints were postoperative complications including anastomotic leakage, reinterventions, hospital stay and mortality within 30 days postoperative.

RESULTS

In total, 2585 patients were included. Twenty-five per cent of all patients received a primary anastomosis; 51% an anastomosis with defunctioning stoma, and 24% an end-colostomy. More than one third of patients developed postoperative complications, the lowest rate being in the primary anastomosis group. Anastomotic leakage rates were 12% in patients with a primary anastomosis, and 9% in patients with an anastomosis with defunctioning stoma (p < 0.05). Multivariate analysis showed more postoperative complications, prolonged hospital stay, and increased mortality rates in patients with a defunctioning stoma or end-colostomy. The latter had proportionally less invasive reinterventions when compared to the other two groups.

CONCLUSIONS

Patients with a primary anastomosis had the best postoperative outcome. A defunctioning stoma leads to a lower anastomotic leakage rate, though is associated with higher rates of complications, prolonged hospital stay and mortality. The decision to create a defunctioning stoma should be focus of future studies.