The difficulty with measuring the largest melanoma tumour diameter in sentinel lymph nodes

Identification of sentinel node (SN) metastases can set the adjuvant systemic therapy indication for stage III melanoma patients. For stage IIIA patients, a 1.0 mm threshold for the largest SN tumour diameter is used. Therefore, uniform reproducible measurement of its size is crucial. At present, the number of deposits or their microanatomical sites are not part of the inclusion criteria for adjuvant treatment. The goal of the current study was to show examples of the difficulty of measuring SN melanoma tumour diameter and teach how it should be measured. Histopathological slides of SN-positive melanoma patients were retrieved using the Dutch Pathology Registry (PALGA). Fourteen samples with the largest SN metastasis around 1.0 mm were uploaded via tele-pathology and digitally measured by 12 pathologists to reflect current practice of measurements in challenging cases. Recommendations as educational examples were provided. Microanatomical location of melanoma metastases was 1 subcapsular, 2 parenchymal and 11 combined. The smallest and largest difference in measurements were 0.24 mm and 4.81 mm, respectively. 11/14 cases (78.6%) showed no agreement regarding the 1.0 mm cut-off. The median discrepancy for cases ≤5 deposits was 0.5 mm (range 0.24-0.60, n=3) and 2.51 mm (range 0.71-4.81, n=11) for cases with ≥6 deposits. Disconcordance in measuring SN tumour burden is correlated with the number of deposits. Awareness of this discordance in challenging cases, for example, cases with multiple small deposits, is important for clinical management. Illustrating cases to reduce differences in size measurement are provided.

Prognostic value of histopathologic traits independent of stromal tumor-infiltrating lymphocyte levels in chemotherapy-naïve patients with triple-negative breast cancer

BACKGROUND

In the absence of prognostic biomarkers, most patients with early-stage triple-negative breast cancer (eTNBC) are treated with combination chemotherapy. The identification of biomarkers to select patients for whom treatment de-escalation or escalation could be considered remains an unmet need. We evaluated the prognostic value of histopathologic traits in a unique cohort of young, (neo)adjuvant chemotherapy-naïve patients with early-stage (stage I or II), node-negative TNBC and long-term follow-up, in relation to stromal tumor-infiltrating lymphocytes (sTILs) for which the prognostic value was recently reported.

MATERIALS AND METHODS

We studied all 485 patients with node-negative eTNBC from the population-based PARADIGM cohort which selected women aged <40 years diagnosed between 1989 and 2000. None of the patients had received (neo)adjuvant chemotherapy according to standard practice at the time. Associations between histopathologic traits and breast cancer-specific survival (BCSS) were analyzed with Cox proportional hazard models.

RESULTS

With a median follow-up of 20.0 years, an independent prognostic value for BCSS was observed for lymphovascular invasion (LVI) [adjusted (adj.) hazard ratio (HR) 2.35, 95% confidence interval (CI) 1.49-3.69], fibrotic focus (adj. HR 1.61, 95% CI 1.09-2.37) and sTILs (per 10% increment adj. HR 0.75, 95% CI 0.69-0.82). In the sTILs <30% subgroup, the presence of LVI resulted in a higher cumulative incidence of breast cancer death (at 20 years, 58%; 95% CI 41% to 72%) compared with when LVI was absent (at 20 years, 32%; 95% CI 26% to 39%). In the ≥75% sTILs subgroup, the presence of LVI might be associated with poor survival (HR 11.45, 95% CI 0.71-182.36, two deaths). We confirm the lack of prognostic value of androgen receptor expression and human epidermal growth factor receptor 2 -low status.

CONCLUSIONS

sTILs, LVI and fibrotic focus provide independent prognostic information in young women with node-negative eTNBC. Our results are of importance for the selection of patients for de-escalation and escalation trials.

Cumulative incidence and timing of subsequent cutaneous squamous cell carcinomas stratified for patients with organ transplantation and hematologic malignancies: A nationwide cohort study

BACKGROUND

There is lack of nationwide data on the cumulative incidence and timing of subsequent cutaneous squamous cell carcinomas (cSCCs) among patients with a first cSCC.

OBJECTIVE

To investigate the cumulative incidence and timing of subsequent cSCCs.

METHODS

Patients with a first cSCC in 2007/2008 from the Netherlands Cancer Registry were linked to the Netherlands Pathology Registry for subsequent cSCCs and the Netherlands Organ Transplant Registry. Cumulative incidence function curves were calculated for subsequent cSCCs and stratified for immune status.

RESULTS

Among the 12,345 patients, second to sixth cSCC occurred in 4325, 2010, 1138, 739, and 501 patients, with median time intervals of 1.4, 1.2, 0.9, 0.6, and 0.5 years after the previous cSCC, respectively. The cumulative incidence of a subsequent cSCC at 5 years increased from 28% to 67% for the second to sixth cSCC. For solid organ transplant recipients, the cumulative incidences increased from 74% to 92% and from 41% to 64% for patients with hematologic malignancy.

LIMITATIONS

Only histopathologically confirmed cSCCs were included.

CONCLUSION

The risk of a subsequent cSCC steeply rises with the number of prior cSCCs and immune status, while the time interval decreases. This can support more informed decisions about follow-up management.

Clinical evaluation of the clinicopathologic and gene expression profile (CP-GEP) in patients with melanoma eligible for sentinel lymph node biopsy: A multicenter prospective Dutch study

Sentinel lymph node biopsy (SLNB) is recommended for patients with >pT1b cutaneous melanoma, and should be considered and discussed with patients diagnosed with pT1b cutaneous melanoma for the purpose of staging, prognostication and determining eligibility for adjuvant therapy. Previously, the clinicopathologic and gene expression profile (CP-GEP, Merlin Assay®) model was developed to identify patients who can forgo SLNB because of a low risk for sentinel node metastasis. The aim of this study was to evaluate the clinical use and implementation of the CP-GEP model in a prospective multicenter study in the Netherlands. Both test performance and feasibility for clinical implementation were assessed in 260 patients with T1-T4 melanoma. The CP-GEP model demonstrated an overall negative predictive value of 96.7% and positive predictive value of 23.7%, with a potential SLNB reduction rate of 42.2% in patients with T1-T3 melanoma. With a median time of 16 days from initiation to return of test results, there was sufficient time left before the SLNB was performed. Based on these outcomes, the model may support clinical decision-making to identify patients who can forgo SLNB in clinical practice.

Personalised decision making to predict absolute metastatic risk in cutaneous squamous cell carcinoma: development and validation of a clinico-pathological model

Background

Cutaneous squamous cell carcinoma (cSCC) is a common skin cancer, affecting more than 2 million people worldwide yearly and metastasising in 2-5% of patients. However, current clinical staging systems do not provide estimates of absolute metastatic risk, hence missing the opportunity for more personalised treatment advice. We aimed to develop a clinico-pathological model that predicts the probability of metastasis in patients with cSCC.

Methods

Nationwide cohorts from (1) all patients with a first primary cSCC in The Netherlands in 2007-2008 and (2) all patients with a cSCC in 2013-2015 in England were used to derive nested case-control cohorts. Pathology records of primary cSCCs that originated a loco-regional or distant metastasis were identified, and these cSCCs were matched to primary cSCCs of controls without metastasis (1:1 ratio). The model was developed on the Dutch cohort (n = 390) using a weighted Cox regression model with backward selection and validated on the English cohort (n = 696). Model performance was assessed using weighted versions of the C-index, calibration metrics, and decision curve analysis; and compared to the Brigham and Women's Hospital (BWH) and the American Joint Committee on Cancer (AJCC) staging systems. Members of the multidisciplinary Skin Cancer Outcomes (SCOUT) consortium were surveyed to interpret metastatic risk cutoffs in a clinical context.

Findings

Eight out of eleven clinico-pathological variables were selected. The model showed good discriminative ability, with an optimism-corrected C-index of 0.80 (95% Confidence interval (CI) 0.75-0.85) in the development cohort and a C-index of 0.84 (95% CI 0.81-0.87) in the validation cohort. Model predictions were well-calibrated: the calibration slope was 0.96 (95% CI 0.76-1.16) in the validation cohort. Decision curve analysis showed improved net benefit compared to current staging systems, particularly for thresholds relevant for decisions on follow-up and adjuvant treatment. The model is available as an online web-based calculator (https://emc-dermatology.shinyapps.io/cscc-abs-met-risk/).

Interpretation

This validated model assigns personalised metastatic risk predictions to patients with cSCC, using routinely reported histological and patient-specific risk factors. The model can empower clinicians and healthcare systems in identifying patients with high-risk cSCC and offering personalised care/treatment and follow-up. Use of the model for clinical decision-making in different patient populations must be further investigated.

Funding

PPP Allowance made available by Health-Holland, Top Sector Life Sciences & Health, to stimulate public-private partnerships.

Ambiguous melanocytic lesions: A retrospective cohort study of incidence and outcome of melanocytic tumor of uncertain malignant potential (MELTUMP) and superficial atypical melanocytic proliferation of uncertain significance (SAMPUS) in the Netherlands

BACKGROUND

Melanocytic tumor of uncertain malignant potential (MELTUMP) and superficial atypical melanocytic proliferation of uncertain significance (SAMPUS) are descriptive and provisional terms for melanocytic tumors with ambiguous histopathological features that are not easily classified as either benign or malignant.

OBJECTIVE

To investigate the incidence and clinical outcome of MELTUMP and SAMPUS in the Netherlands.

METHODS

In this retrospective cohort study, we reviewed all diagnoses of MELTUMP and SAMPUS from the Dutch Nationwide Pathology Databank from 1991 to October 1, 2021. Clinical outcome was studied for cases diagnosed until October 1, 2018.

RESULTS

A total of 1685 MELTUMP and 1957 SAMPUS were identified with an annual incidence of 150 to 300 cases. Metastatic behavior was seen in 0.7% of all initially diagnosed MELTUMP. All SAMPUS remained free of metastases.

LIMITATIONS

Reassessment of pathology slides and confirmation of clonality between primary and metastatic lesions remained outside the scope of this study.

CONCLUSION

Despite the 'uncertainty' in the nomenclature, our results demonstrate a low malignant potential for MELTUMP and no malignant potential for SAMPUS. We emphasize the importance of consultation for ambiguous melanocytic lesions and to limit the MELTUMP/SAMPUS terminology to legitimately uncertain or unclassifiable cases.

Hedgehog pathway mutations are involved in the pathogenesis of plaque-type "trichoblastoma": A report of two cases

We present two cases of plaque-type trichoblastoma with atypical foci. A rare variant of trichoblastoma is the plaque variant, which is characterized by poor circumscription and locally infiltrative growth pattern. These lesions mostly require multiple stages of Mohs micrographic surgery. Debate still exists whether this variant should be considered as a benign entity or as "low-grade" malignant counterpart of trichoblastoma. In this report we describe two cases of plaque-type trichoblastoma with atypical foci, which harbored somatic mutations in the Hedgehog pathway, thus should be acknowledged as intermediate malignancies. In addition, extensive molecular workup of both the trichoblastic and atypical component in sequential lesions in the same patient was performed.

Histopathological and immunological spectrum in response evaluation of talimogene laherparepvec treatment and correlation with durable response in patients with cutaneous melanoma

Talimogene laherparepvec (T-VEC) is an intralesional oncolytic virotherapy for patients with irresectable stage III-IVM1a cutaneous melanoma. Although this treatment is considered to mainly act through T cell-mediated mechanisms, prominent numbers of plasma cells after T-VEC treatment have been described. The aim was to investigate how often these plasma cells were present, whether they were relevant in the response to treatment, and if these or other histopathological features were associated with durable response to treatment. Histopathological (granulomas, perineural inflammation, etc.) and immunological features [e.g. B cells/plasma cells (CD20/CD138) and T cells (CD3,CD4,CD8)] were scored and correlated with durable tumor response [i.e. complete response (CR) persisting beyond 6 months after treatment]. Plasmacellular infiltrate was examined with next-generation sequencing and immunohistochemistry (IgG, IgM, IgA, and IgD). Plasma cells were present in all T-VEC injected biopsies from 25 patients with melanoma taken at 3-5 months after starting treatment. In patients with a durable response ( n = 12), angiocentric features and granulomas were more frequently identified compared with patients without a (durable) response ( n = 13); 75% versus 29% for angiocentric features ( P = 0.015) and 58% versus 15% for granulomas ( P = 0.041). There was a class switch of IgM to IgG with skewing to certain dominant Ig heavy chain clonotypes. An angiocentric granulomatous pattern in T-VEC injected melanoma lesions was associated with a durable CR (>6 months). Plasma cells are probably a relevant feature in the mechanism of response but were not associated with durable response.

Using a Clinicopathologic and Gene Expression (CP-GEP) Model to Identify Stage I-II Melanoma Patients at Risk of Disease Relapse

Background: The current standard of care for patients without sentinel node (SN) metastasis (i.e., stage I−II melanoma) is watchful waiting, while >40% of patients with stage IB−IIC will eventually present with disease recurrence or die as a result of melanoma. With the prospect of adjuvant therapeutic options for patients with a negative SN, we assessed the performance of a clinicopathologic and gene expression (CP-GEP) model, a model originally developed to predict SN metastasis, to identify patients with stage I−II melanoma at risk of disease relapse. Methods: This study included patients with cutaneous melanoma ≥18 years of age with a negative SN between October 2006 and December 2017 at the Sahlgrenska University Hospital (Sweden) and Erasmus MC Cancer Institute (The Netherlands). According to the CP-GEP model, which can be applied to the primary melanoma tissue, the patients were stratified into high or low risk of recurrence. The primary aim was to assess the 5-year recurrence-free survival (RFS) of low- and high-risk CP-GEP. A secondary aim was to compare the CP-GEP model with the EORTC nomogram, a model based on clinicopathological variables only. Results: In total, 535 patients (stage I−II) were included. CP-GEP stratification among these patients resulted in a 5-year RFS of 92.9% (95% confidence interval (CI): 86.4−96.4) in CP-GEP low-risk patients (n = 122) versus 80.7% (95%CI: 76.3−84.3) in CP-GEP high-risk patients (n = 413; hazard ratio 2.93 (95%CI: 1.41−6.09), p < 0.004). According to the EORTC nomogram, 25% of the patients were classified as having a ‘low risk’ of recurrence (96.8% 5-year RFS (95%CI 91.6−98.8), n = 130), 49% as ‘intermediate risk’ (88.4% 5-year RFS (95%CI 83.6−91.8), n = 261), and 26% as ‘high risk’ (61.1% 5-year RFS (95%CI 51.9−69.1), n = 137). Conclusion: In these two independent European cohorts, the CP-GEP model was able to stratify patients with stage I−II melanoma into two groups differentiated by RFS.

Histopathological characteristics are instrumental to distinguish monomorphic from polymorphic maculopapular cutaneous mastocytosis in children

Background

Mastocytosis is characterized by the accumulation of mast cells (MCs) in the skin or other organs, and can manifest at any age. A significant number of paediatric mastocytosis cases persist after puberty. In particular, monomorphic maculopapular cutaneous mastocytosis (mMPCM) is often persistent and associated with systemic mastocytosis. However, clinical differentiation of MPCM from polymorphic (p)MPCM can be difficult.

Aim

To identify histopathological features that can help to distinguish mMPCM from other subtypes of paediatric mastocytosis.

Methods

This was a retrospective study using skin biopsies from patients with any subtype of mastocytosis. The localization and density of the MC infiltrate, MC morphology and expression of aberrant markers were evaluated and correlated with clinical characteristics.

Results

In total, 33 biopsies were available for evaluation from 26 children [(10 with mMPCM, 5 with mastocytoma, 3 with diffuse cutaneous mastocytosis (DCM), 8 with pMPCM)] and 7 adults with MPCM. The MC number was increased in all patients, but was higher in children than adults (P < 0.01). The presence of mMPCM was associated with sparing of the papillary dermis from MC infiltration, whereas MC density in the papillary dermis was highest in pMPCM and DCM (P < 0.01). The positive predictive value of the presence of a reticular MC infiltrate for mMPCM was 72.7% (95% CI 51.4–87.0), and the negative predictive value was 83.3% (95% CI 42.2–97.2). There were no relevant differences in the expression of CD2, CD25 or CD30 between the different subtypes.

Conclusion

Skin histopathology might enhance the phenotypical differentiation of mMPCM from other subtypes in children, thereby increasing the accuracy of one's prognosis.

Prognostic Value of Stromal Tumor-Infiltrating Lymphocytes in Young, Node-Negative, Triple-Negative Breast Cancer Patients Who Did Not Receive (neo)Adjuvant Systemic Therapy

PURPOSE

Triple-negative breast cancer (TNBC) is considered aggressive, and therefore, virtually all young patients with TNBC receive (neo)adjuvant chemotherapy. Increased stromal tumor-infiltrating lymphocytes (sTILs) have been associated with a favorable prognosis in TNBC. However, whether this association holds for patients who are node-negative (N0), young (< 40 years), and chemotherapy-naïve, and thus can be used for chemotherapy de-escalation strategies, is unknown.

METHODS

We selected all patients with N0 TNBC diagnosed between 1989 and 2000 from a Dutch population–based registry. Patients were age < 40 years at diagnosis and had not received (neo)adjuvant systemic therapy, as was standard practice at the time. Formalin-fixed paraffin-embedded blocks were retrieved (PALGA: Dutch Pathology Registry), and a pathology review including sTILs was performed. Patients were categorized according to sTILs (< 30%, 30%-75%, and ≥ 75%). Multivariable Cox regression was performed for overall survival, with or without sTILs as a covariate. Cumulative incidence of distant metastasis or death was analyzed in a competing risk model, with second primary tumors as competing risk.

RESULTS

sTILs were scored for 441 patients. High sTILs (≥ 75%; 21%) translated into an excellent prognosis with a 15-year cumulative incidence of a distant metastasis or death of only 2.1% (95% CI, 0 to 5.0), whereas low sTILs (< 30%; 52%) had an unfavorable prognosis with a 15-year cumulative incidence of a distant metastasis or death of 38.4% (32.1 to 44.6). In addition, every 10% increment of sTILs decreased the risk of death by 19% (adjusted hazard ratio: 0.81; 95% CI, 0.76 to 0.87), which are an independent predictor adding prognostic information to standard clinicopathologic variables (χ² = 46.7, P < .001).

CONCLUSION

Chemotherapy-naïve, young patients with N0 TNBC with high sTILs (≥ 75%) have an excellent long-term prognosis. Therefore, sTILs should be considered for prospective clinical trials investigating (neo)adjuvant chemotherapy de-escalation strategies.

Young cancer patients with TNBC and high sTILs have an excellent outcome, even without systemic treatment

Assessment of the Diagnostic Accuracy of Baseline Clinical Examination and Ultrasonographic Imaging for the Detection of Lymph Node Metastasis in Patients With High-risk Cutaneous Squamous Cell Carcinoma of the Head and Neck

IMPORTANCE

Patients with cutaneous squamous cell carcinoma (SCC) of the head and neck may develop lymph node metastasis; therefore, additional workup of the regional lymph nodes in these patients should be considered. However, there is uncertainty regarding the value of baseline ultrasonographic imaging in addition to clinical examination for the detection of metastasis.

OBJECTIVE

To assess the diagnostic accuracy of clinical examination and baseline ultrasonography for the detection of metastasis among patients with high-risk cutaneous SCC of the head and neck and to assess the accuracy of ultrasonography when baseline clinical examination produces negative results.

DESIGN, SETTING, AND PARTICIPANTS

This diagnostic study was conducted among a retrospective cohort of 233 patients with 246 high-risk cutaneous SCC tumors of the head and neck. The study included all patients with high-risk cutaneous SCC of the head and neck who received clinical examination and baseline ultrasonographic imaging of their lymph nodes at the Erasmus Medical Center Cancer Institute, a tertiary referral hospital for patients with skin cancer in Rotterdam, the Netherlands, between January 1, 2015, and December 31, 2017. Data were analyzed from October 13, 2020, to September 29, 2021.

MAIN OUTCOMES AND MEASURES

Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. Fine-needle aspiration cytologic biopsy and 6 months of follow-up per patient were used as the reference standards.

RESULTS

Among 233 patients (176 men [75.5%]; median age, 79.1 years [IQR, 71.5-83.7 years]; data on race and ethnicity were not collected) with 246 high-risk cutaneous SCC tumors of the head and neck, 20 metastases were cytologically confirmed at baseline, and 2 metastases were detected during 6 months of follow-up, yielding a 9% metastasis rate. The sensitivity of clinical examination was 50% (95% CI, 28%-72%), and the specificity was 96% (95% CI, 93%-98%). The PPV and NPV were 55% (95% CI, 36%-72%) and 95% (95% CI, 93%-97%), respectively. In the total cohort, ultrasonography had a sensitivity of 91% (95% CI, 71%-99%) and a specificity of 78% (95% CI, 72%-83%), with a PPV of 29% (95% CI, 23%-35%) and an NPV of 99% (95% CI, 96%-100%). In the group of patients with negative results at baseline clinical examination, 9 of 11 metastases were detected by ultrasonography, with 82% sensitivity (95% CI, 48%-98%); specificity was 79% (95% CI, 73%-84%), PPV was 17% (95% CI, 12%-23%), and NPV was 99% (95% CI, 96%-100%).

CONCLUSIONS AND RELEVANCE

In this diagnostic study, among a cohort of patients with high-risk cutaneous SCC of the head and neck, baseline ultrasonography was more sensitive than clinical examination alone for the detection of lymph node metastasis. In the setting of a negative result at baseline clinical examination, ultrasonography had high sensitivity for detecting nodal metastases, but this sensitivity should be evaluated against the high rate of false-positive findings.

Validation of Four Cutaneous Squamous Cell Carcinoma Staging Systems Using Nationwide Data

Background

Cutaneous squamous cell carcinoma (cSCC) is the second most common cancer worldwide with relatively low metastatic potential (2–5%). Developments in therapeutic options have highlighted the need to better identify high‐risk patients who could benefit from closer surveillance, adjuvant therapies and baseline/follow‐up imaging, while at the same time safely omitting low‐risk patients from further follow‐up. Controversy remains regarding the predictive performance of current cSCC staging systems and which methodology to adopt.

Objectives

To validate the performance of four cSCC staging systems [American Joint Committee on Cancer 8th edition (AJCC8), Brigham and Women’s Hospital (BWH), Tübingen and Salamanca T3 refinement] in predicting metastasis using a nationwide cohort.

Methods

A nested case–control study using data from the National Disease Registration Service, England, 2013–2015 was conducted. Metastatic cSCC cases were identified using an algorithm to identify all potential cases for manual review. These were 1 : 1 matched on follow‐up time to nonmetastatic controls randomly selected from 2013. Staging systems were analysed for distinctiveness, homogeneity, monotonicity, specificity, positive predictive value (PPV), negative predictive value (NPV) and c‐index.

Results

We included 887 metastatic cSCC cases and 887 nonmetastatic cSCC controls. The BWH system showed the highest specificity [92.8%, 95% confidence interval (CI) 90.8–94.3%, PPV (13.2%, 95% CI 10.6–16.2) and c‐index (0.84, 95% CI 0.82–0.86). The AJCC8 showed superior NPV (99.2%, 95% CI 99.2–99.3), homogeneity and monotonicity compared with the BWH and Tübingen diameter and thickness classifications (P < 0.001). Salamanca refinement did not show any improvement in AJCC8 T3 cSCC staging.

Conclusions

We validated four cSCC staging systems using the largest nationwide dataset of metastatic cSCC so far. Although the BWH system showed the highest overall discriminative ability, PPV was low for all staging systems, which shows the need for further improvement and refining of current cSCC staging systems.

False positive FDG uptake in melanoma patients treated with talimogene laherparepvec (T-VEC)

Talimogene laherparepvec (T-VEC) is a genetically modified herpes simplex virus-1-based oncolytic immunotherapy and has been approved for the local treatment of unresectable (stage IIIB/C and IVM1a) cutaneous melanoma. During T-VEC treatment, tumor response is often evaluated using [18F]2-fluoro-2-deoxy- d-glucose(FDG) positron emission tomography/computed tomography (PET/CT). In a Dutch cohort (n = 173), almost one-third of patients developed new-onset FDG uptake in uninjected locoregional lymph nodes during T-VEC. In 36 out of 53 (68%) patients with new nodal FDG uptake, nuclear medicine physicians classified this FDG uptake as "suspected metastases" without clinical or pathological confirmation in the majority of patients. These false positive results indicate that new-onset FDG uptake in locoregional lymph nodes during T-VEC treatment does not necessarily reflect progressive disease, but may be associated with immune infiltration. In current clinical practice, physicians should be aware of the high false positive rate of FDG uptake during treatment with T-VEC in patients with melanoma. Therefore, pathological examination of lymph node lesions with new FDG uptake is recommended to differentiate between progressive disease and immune infiltration after treatment with T-VEC.

Cumulative incidence and disease-specific survival of metastatic cutaneous squamous cell carcinoma: A nationwide cancer registry study

BACKGROUND

Cutaneous squamous cell carcinoma (cSCC) represents the most serious form of keratinocyte cancers because of its metastatic potential. Studies on nationwide incidence and disease-specific survival rates of metastatic cSCC (mcSCC) are lacking.

OBJECTIVE

To investigate the cumulative incidence and disease-specific survival of patients with mcSCC in the Dutch population and assess patient-based risk factors.

METHODS

We conducted a nationwide cancer registry study including all patients with the first cSCC in 2007 or 2008, using data from the Netherlands Cancer Registry, the nationwide network and registry of histopathology and cytopathology, and Statistics Netherlands. Cumulative incidence and Kaplan-Meier curves were calculated, and time-dependent Cox proportional hazards regression analyses were used.

RESULTS

Of the 11,137 patients, metastases developed in 1.9% (n = 217). The median time to metastasis was 1.5 years (interquartile range 0.6-3.8 years). The risk factors were age (adjusted hazard ratio [aHR] 1.03, 95% CI 1.02-1.05), male sex (aHR 1.7, 95% CI 1.3-2.3), and immunosuppression (aHR [organ transplant recipient] 5.0, 95% CI 2.5-10.0; aHR [hematologic malignancy] 2.7, 95% CI 1.6-4.6). The 5-year disease-specific survival for patients with mcSCC was 79.1%.

LIMITATIONS

Only histopathologically confirmed mcSCCs were included.

CONCLUSION

About 2% of cSCCs metastasize, with higher risk for men, increasing age, and immunocompromised patients. Disease-specific survival for patients with mcSCC is high.

Validation of a clinicopathological and gene expression profile model for sentinel lymph node metastasis in primary cutaneous melanoma

BACKGROUND

The Clinicopathological and Gene Expression Profile (CP-GEP) model was developed to accurately identify patients with T1-T3 primary cutaneous melanoma at low risk for nodal metastasis.

OBJECTIVES

To validate the CP-GEP model in an independent Dutch cohort of patients with melanoma.

METHODS

Patients (aged ≥ 18 years) with primary cutaneous melanoma who underwent sentinel lymph node biopsy (SLNB) between 2007 and 2017 at the Erasmus Medical Centre Cancer Institute were eligible. The CP-GEP model combines clinicopathological features (age and Breslow thickness) with the expression of eight target genes involved in melanoma metastasis (ITGB3, PLAT, SERPINE2, GDF15, TGFBR1, LOXL4, CXCL8 and MLANA). Using the pathology result of SLNB as the gold standard, performance measures of the CP-GEP model were calculated, resulting in CP-GEP high risk or low risk for nodal metastasis.

RESULTS

In total, 210 patients were included in the study. Most patients presented with T2 (n = 94, 45%) or T3 (n = 70, 33%) melanoma. Of all patients, 27% (n = 56) had a positive SLNB, with nodal metastasis in 0%, 30%, 54% and 16% of patients with T1, T2, T3 and T4 melanoma, respectively. Overall, the CP-GEP model had a negative predictive value (NPV) of 90·5% [95% confidence interval (CI) 77·9-96.2], with an NPV of 100% (95% CI 72·2-100) in T1, 89·3% (95% CI 72·8-96·3) in T2 and 75·0% (95% CI 30·1-95·4) in T3 melanomas. The CP-GEP indicated high risk in all T4 melanomas.

CONCLUSIONS

The CP-GEP model is a noninvasive and validated tool that accurately identified patients with primary cutaneous melanoma at low risk for nodal metastasis. In this validation cohort, the CP-GEP model has shown the potential to reduce SLNB procedures in patients with melanoma.

Trichoblastic carcinosarcoma with panfollicular differentiation (panfollicular carcinosarcoma) and CTNNB1 (beta-catenin) mutation

We present a case of trichoblastic carcinosarcoma with panfollicular differentiation. An 80-year-old man presented with a lesion on the left ear, which had been present for several months. Histopathology revealed a well-demarcated neoplasm in the dermis composed of intimately intermingled malignant epithelial and mesenchymal cells. The epithelial component showed multilineage follicular differentiation toward all of the elements of a normal hair follicle. Molecular analysis revealed identical molecular aberrations in both epithelial and mesenchymal components including CTNNB1 and SUFU mutations. To the best of our knowledge, this is the first report of panfollicular carcinosarcoma and of the presence of a CTNNB1 mutation in trichoblastic carcinosarcoma.

Molecular testing in metastatic basal cell carcinoma

BACKGROUND

Metastatic basal cell carcinoma (mBCC) is a very rare entity, and diagnosis can be challenging. Therapeutic options are limited, and response to targeted therapy is poor.

OBJECTIVE

To demonstrate a clonal relationship between BCCs and their metastases and to explore which hedgehog pathway-related mutations are involved in mBCC.

METHODS

Genetic analysis was conducted in 10 primary BCCs and their metastases. Genes relevant for BCC development were analyzed in tumor and metastasis material with small molecule molecular inversion probes (smMIPs) for PTCH1, PTCH2, SMO, SUFU, GLI2, and TP53 or with targeted next generation sequencing of the same genes and CDKN2A, CDKN2B, CIC, DAXX, DDX3X, FUBP1, NF1, NF2, PTEN, SETD2, TRAF7, and the TERT promoter.

RESULTS

In 8 of 10 patients, identical gene mutations could be demonstrated in the primary tumors and their metastases. A broad spectrum of mutations was found. Four patients had SMO mutations in their tumor or metastasis, or both. All SMO mutations found were known to cause resistance to targeted therapy with vismodegib.

LIMITATIONS

In 2 patients there was insufficient qualitative DNA available for genetic analysis.

CONCLUSIONS

Molecular testing can help to identify the origin of a BCC metastasis and may be of prognostic and therapeutic value.

Disrupted regulation of serpinB9 in circulating T cells is associated with an increased risk for post-transplant skin cancer

Cutaneous squamous cell carcinoma (cSCC) is a serious complication after organ transplantation and patients benefit from an early risk assessment. We hypothesized that functional differences in circulating T cells may represent risk factors for post‐transplant cSCC development. Here, we analysed genome‐wide DNA methylation of circulating T cells of kidney transplant recipients before the clinical onset of cSCC, to identify differences associated with post‐transplant cSCC development. This analysis identified higher DNA methylation of SERPINB9, which is an intracellular inhibitor of granzyme B, a protein that induces apoptosis in target cells. High DNA methylation of SERPINB9 in circulating T cells was confirmed in a second patient cohort during recurrent cSCC, indicating that high SERPINB9 methylation represents a persistent risk factor for cSCC development. At the functional level, the inverse correlation between DNA methylation and messenger RNA expression present in non‐cSCC patients was absent in the cSCC patients. Also, a significant difference in serpinB9 protein expression between cSCC patients and non‐cSCC patients was observed. It was concluded that disturbed regulation of serpinB9 in circulating T cells represents a novel risk factor for post‐transplant cSCC in kidney transplant recipients.

Recurrence rates of cutaneous squamous cell carcinoma of the head and neck after Mohs micrographic surgery vs. standard excision: a retrospective cohort study

BACKGROUND

Recurrent cutaneous squamous cell carcinoma (cSCC) has been associated with an increased risk of local functional and aesthetic comorbidity, metastasis and mortality.

OBJECTIVES

To compare the risk of recurrence between Mohs micrographic surgery (MMS) and standard excision for cSCC of the head and neck.

METHODS

This was a retrospective cohort study of all patients with a cSCC treated with MMS or standard excision at the departments of dermatology of a secondary or tertiary care hospital in the Netherlands between 2003 and 2012. To detect all recurrences, patients were linked to the Dutch pathology registry. To compare the risk of recurrence between MMS and standard excision, hazard ratios (HRs) were used adjusted for clinical tumour size > 2 cm and deep tumour invasion.

RESULTS

A total of 579 patients with 672 cSCCs were included: 380 cSCCs were treated with MMS and 292 with standard excision. The risk of recurrence was 8% (22 of 292) after standard excision during a median follow-up of 5·7 years [interquartile range (IQR) 3·5-7·8], which was higher than the 3% (12 of 380) after MMS during a median follow-up of 4·9 years (IQR 2·3-6·0). The cumulative incidence of recurrence was higher for standard excision than for MMS during the entire follow-up period of 8·6 years. Carcinomas treated with MMS were at a three times lower risk of recurrence than those treated with standard excision when adjusted for tumour size and deep tumour invasion (adjusted HR 0·31, 95% confidence interval 0·12-0·66).

CONCLUSIONS

MMS might be superior to standard excision for cSCCs of the head and neck because of a lower rate of recurrence.

Long-term prognosis of young breast cancer patients (≤40 years) who did not receive adjuvant systemic treatment: protocol for the PARADIGM initiative cohort study

INTRODUCTION

Currently used tools for breast cancer prognostication and prediction may not adequately reflect a young patient's prognosis or likely treatment benefit because they were not adequately validated in young patients. Since breast cancers diagnosed at a young age are considered prognostically unfavourable, many treatment guidelines recommend adjuvant systemic treatment for all young patients. Patients cured by locoregional treatment alone are, therefore, overtreated. Lack of prognosticators for young breast cancer patients represents an unmet medical need and has led to the initiation of the PAtients with bReAst cancer DIaGnosed preMenopausally (PARADIGM) initiative. Our aim is to reduce overtreatment of women diagnosed with breast cancer aged ≤40 years.

METHODS AND ANALYSIS

All young, adjuvant systemic treatment naive breast cancer patients, who had no prior malignancy and were diagnosed between 1989 and 2000, were identified using the population based Netherlands Cancer Registry (n=3525). Archival tumour tissues were retrieved through linkage with the Dutch nationwide pathology registry. Tissue slides will be digitalised and placed on an online image database platform for clinicopathological revision by an international team of breast pathologists. Immunohistochemical subtype will be assessed using tissue microarrays. Tumour RNA will be isolated and subjected to next-generation sequencing. Differences in gene expression found between patients with a favourable and those with a less favourable prognosis will be used to establish a prognostic classifier, using the triple negative patients as proof of principle.

ETHICS AND DISSEMINATION

Observational data from the Netherlands Cancer Registry and left over archival patient material are used. Therefore, the Dutch law on Research Involving Human Subjects Act (WMO) is not applicable. The PARADIGM study received a 'non-WMO' declaration from the Medical Ethics Committee of the Netherlands Cancer Institute - Antoni van Leeuwenhoek hospital, waiving individual patient consent. All data and material used are stored in a coded way. Study results will be presented at international (breast cancer) conferences and published in peer-reviewed, open-access journals.

Abstract 1751: Systematic bias in genomic breast cancer classification due to selecting cases with high tumor percentage and good RNA quality

Background

Cancer classification, prognostication, and prediction of treatment sensitivity increasingly rely on DNA and RNA-based tests. This approach requires sufficiently high tumor cell percentages to yield enough DNA or RNA for reliable test results. As a consequence, samples of insufficient quality may drop out, e.g. due to poor cellularity or high numbers of tumor infiltrating lymphocytes. We hypothesized that requiring a high tumor cell percentage and high quality RNA causes systemic bias when interpreting genomic test results in breast cancer, as specific breast cancer subgroups may be over- or underrepresented.

Patients and methods

For this analysis, we used pre-treatment frozen samples from patients included in neoadjuvant chemotherapy trials at the Netherlands Cancer Institute between 2004 and 2012. Histological features and tumor cell percentage were reviewed and assessed by a consultant breast pathologist. Gene expression profiling was done if the tumor cell percentage exceeded 50% and RNA quantity (&gt;1 µg) and quality (RIN value≥ 6.5) were sufficient. We compared patient and tumor characteristics between patients in whom gene expression profiling could be performed and those in whom it could not be performed. In addition, we performed a systematic review on gene expression profiling for breast cancer, to assess the percentage of sample dropout in published studies.

Results

Frozen biopsies were available from 658 patients (79% of the total study population) and gene expression profiling could be performed in 60% of the cases, a percentage comparable to what is reported in the literature. Reasons for drop out were a low cellularity, poor quality and quantity of the RNA, or a too small biopsy for processing. These patients had more grade 3 tumors (43% versus 34%, p=0.04) and were more node positive (76% versus 69%, p=0.03). Analysis of neoadjuvant chemotherapy response and survival in these patients is ongoing and will be presented at the AACR Annual Meeting 2017.

Conclusion

Breast cancers for which gene expression data were successfully obtained were associated with a higher grade and with lymph node metastasis. Such tumors represent a more aggressive phenotype and have a relatively poor prognosis, compared to the patients for whom gene expression data could not be measured. As gene expression arrays are now broadly used in a clinical context, it is important to acknowledge this systematic bias, and to be cautious in applying gene expression based tests on different patient populations than a test was developed on.

Citation Format: Esther H. Lips, Antien L. Mooyaart, Maartje van Seijen, Lennart Mulder, Marlous Hoogstraat, Petra M. Nederlof, Lodewyk F. Wessels, Sjoerd Rodenhuis, Gabe S. Sonke, Jelle Wesseling. Systematic bias in genomic breast cancer classification due to selecting cases with high tumor percentage and good RNA quality [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1751. doi:10.1158/1538-7445.AM2017-1751

Long-term outcome of breast cancer patients diagnosed ≤40 years according to breast cancer subtype in the absence of adjuvant systemic therapy: The PARADIGM initiative

535

Background: Young age at breast cancer diagnosis is considered a poor prognostic factor. As a result, many treatment guidelines advice adjuvant systemic treatment for young patients. Answering prognostic questions on young patients has therefore become a challenge. The PARADIGM (PAtients with bReast cAncer DIaGnosed preMenopausally) project aims to assess the long-term outcome of women diagnosed with breast cancer ≤40 years in the absence of adjuvant systemic therapy, using real world data from the nationwide Netherlands Cancer Registry (NCR) coupled with tissue biobanking. Methods: All women ≤40 years, diagnosed in the Netherlands between 1989-2000 with a primary invasive, histologically proven, TanyN0M0 breast cancer, without adjuvant systemic treatment were identified through the NCR. Back then N0 patients were considered low risk and did not receive adjuvant systemic treatment. Tissue specimens were revised by a team of dedicated breast pathologists. Cox regression was performed to estimate hazard ratios for recurrence-free (RFS) and overall survival (OS) according to immunohistochemical (IHC) subtype. Analyses were adjusted for grade, pathological T-stage, histological subtype and radiotherapy. Results: We included 2310 patients with a mean follow-up of 15.4 years (range 0-25 years). OS for the whole cohort was 68% and RFS 58.4% at 25 years. In total 740 deaths and 1043 recurrences were observed. Hormone receptor (HR)+/HER2+ patients had a significantly worse OS when compared to HR-HER2+ patients (adjusted Hazard Ratio 1.58; 95% confidence interval 1.05-2.38; p=0.029). No difference was observed between HR-HER2+ and the triple negative and HR+/HER2- subgroups at 25-years. RFS was similar for all IHC subtypes. Conclusions: In this large cohort of non-adjuvant systemically treated young breast cancer patients with long-term follow-up HR+/HER2+ patients have a significantly worse survival when compared to triple negative, HR-/HER2+ and HR+/HER2- patients. The latter three subtypes have similar OS at 25 years. Future molecular studies have been planned to distinguish the favorable from the unfavorable prognostic patients.

Abstract P5-08-07: The long-term prognosis of breast cancers patients diagnosed ≤40 years in the absence of adjuvant systemic therapy

This abstract was withdrawn by the authors.

Linking uterine serous carcinoma to BRCA1/2-associated cancer syndrome: A meta-analysis and case report

BACKGROUND

Uterine serous carcinoma (USC) shows greater morphological, clinical and molecular similarities to high-grade ovarian tubal serous carcinoma than to other types of endometrial cancer. As high-grade ovarian tubal serous carcinoma is known to be associated with BRCA1/2 pathogenic germline mutations (PMs), we aimed to explore whether USC is also a constituent of hereditary breast and ovarian cancer syndrome.

METHODS

Pubmed, EMBASE and Web of Science were searched in July 2016 for articles assessing the association between USC and germline BRCA1/2-PMs. Pooled analysis and comparisons were performed using a random effects logistic model, stratifying for ethnicity (Ashkenazi versus non-Ashkenazi). In addition, tumour tissue from an USC case with a hereditary BRCA1-PM was analysed for loss of heterozygosity at the BRCA1 locus and was functionally analysed for homologous recombination proficiency.

RESULTS

The search yielded 1893 citations, 10 studies were included describing 345 USC patients. For Ashkenazi Jews, the pooled odds ratio of having a germline BRCA1/2-PM was increased in USC patients compared with the general Ashkenazi population: odds ratio 5.4 (95%confidence interval: 2.2-13.1). In the patient with USC, we identified the known germline BRCA1-PM in the tumour DNA. Furthermore, we showed both loss of heterozygosity of the wild-type allele and a deficiency of homologous recombination.

CONCLUSION

This study suggests that USC may be an overlooked component of BRCA1/2-associated hereditary breast and ovarian cancer syndrome. Screening for germline BRCA1/2-PMs should be considered in patients diagnosed with USC, especially in cases with a positive first-degree family history for breast and/or ovarian cancer.

Abstract P3-07-54: Insulin-like growth factor 1 receptor expression and polymorphism are associated with response to neoadjuvant chemotherapy in breast cancer patients: Results from the NEOZOTAC trial (BOOG 2010-01)

Background

The insulin-like growth factor 1 (IGF-1) pathway is involved in cell growth, proliferation and cell cycle progression and associated with tumor genesis and therapy resistance. This study aims to elucidate whether variation in the IGF-1 pathway is predictive for pathologic response in early breast cancer (BC) patients taking part in the phase III NEOZOTAC trial, randomizing between 6 cycles of neoadjuvant TAC chemotherapy with or without zoledronic acid.

Method

Formalin-fixed paraffin-embedded (FFPE) tissue samples of pre-chemotherapy biopsies and operation specimens were collected for analysis of IGF-1 receptor (IGF-1R) expression using IHC (n=216) and for analysis of 8 candidate SNPs in genes of the IGF-1 pathway (n=184) using OpenArray® RealTime PCR. Optionally, blood samples were collected immediately before chemotherapy for determination of glucose, insulin, IGF-1, IGF-2 and IGF-BP3. Associations with patient and tumor characteristics and chemotherapy response according to Miller and Payne (MP) pathologic response were performed using chi square and logistic regression analyses.

Results

High IGF-1R expression was associated with estrogen receptor expression (P=0.001). During chemotherapy, a significant number of the tumors (47.2%) showed a decrease in IGF-1R expression, while in a small number of the tumors an upregulation was seen (15.1%). IGF-1R expression before treatment was not associated with pathological response, however absence of IGF-1R expression after treatment was associated with a better response in multivariate analyses (P=0.012) and patients with a decrease in expression during treatment showed a better response to chemotherapy as well (P=0.008). Moreover, the variant T allele of 3129G&gt;T in IGF-1R (rs2016347) was associated with a better pathological response in multivariate analyses (P=0.032). In addition, high glucose and insulin levels were associated with positive lymph node status before chemotherapy in multivariate analysis (P=0.019) and (P=0.031), respectively.

Conclusion

Neoadjuvant chemotherapy induced changes in the IGF-1R expression in most of the tumors. Absence or diminished expression of IGF-1R after treatment was associated with a better pathological response. Additionally, we found a SNP (rs2016347) in IGF-1R as a potential predictive marker for chemotherapy efficacy in BC patients treated with TAC. These findings may help to select patients who might benefit from (co-)treatment with an IGF-1 pathway inhibitor.

Citation Format: de Groot S, Charehbili A, van Laarhoven HWM, Mooyaart AL, Dekker-Ensink NG, van de Ven S, Janssen LGM, Swen JJ, Smit VTHBM, Heijns JB, Kessels LW, van der Straaten RJHM, Bhringer S, Gelderblom AJ, van der Hoeven JJM, Guchelaar HJ, Pijl H, Kroep JR. Insulin-like growth factor 1 receptor expression and polymorphism are associated with response to neoadjuvant chemotherapy in breast cancer patients: Results from the NEOZOTAC trial (BOOG 2010-01). [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-07-54.

Insulin-like growth factor 1 receptor expression and IGF1R 3129G > T polymorphism are associated with response to neoadjuvant chemotherapy in breast cancer patients: results from the NEOZOTAC trial (BOOG 2010-01)

Background

The insulin-like growth factor 1 (IGF-1) pathway is involved in cell growth and proliferation and is associated with tumorigenesis and therapy resistance. This study aims to elucidate whether variation in the IGF-1 pathway is predictive for pathologic response in early HER2 negative breast cancer (BC) patients, taking part in the phase III NEOZOTAC trial, randomizing between 6 cycles of neoadjuvant TAC chemotherapy with or without zoledronic acid.

Methods

Formalin-fixed paraffin-embedded tissue samples of pre-chemotherapy biopsies and operation specimens were collected for analysis of IGF-1 receptor (IGF-1R) expression (n = 216) and for analysis of 8 candidate single nucleotide polymorphisms (SNPs) in genes of the IGF-1 pathway (n = 184) using OpenArray® RealTime PCR. Associations with patient and tumor characteristics and chemotherapy response according to Miller and Payne pathologic response were performed using chi-square and regression analysis.

Results

During chemotherapy, a significant number of tumors (47.2 %) showed a decrease in IGF-1R expression, while in a small number of tumors an upregulation was seen (15.1 %). IGF-1R expression before treatment was not associated with pathological response, however, absence of IGF-1R expression after treatment was associated with a better response in multivariate analysis (P = 0.006) and patients with a decrease in expression during treatment showed a better response to chemotherapy as well (P = 0.020). Moreover, the variant T allele of 3129G > T in IGF1R (rs2016347) was associated with a better pathological response in multivariate analysis (P = 0.032).

Conclusions

Absent or diminished expression of IGF-1R after neoadjuvant chemotherapy was associated with a better pathological response. Additionally, we found a SNP (rs2016347) in IGF1R as a potential predictive marker for chemotherapy efficacy in BC patients treated with TAC.

Trial registration

ClinicalTrials.gov NCT01099436. Registered April 6, 2010.

The clinical prognostic value of molecular intrinsic tumor subtypes in older breast cancer patients: A FOCUS study analysis

INTRODUCTION

It was recently proposed that the molecular breast tumor subtypes are differently distributed in the elderly breast cancer patients, and also lack prognostic value. Given the limited number of elderly patients in previous studies, the aim of this study was to determine the prognostic effect of the molecular intrinsic subtypes in a large older breast cancer population.

MATERIAL AND METHOD

Older breast cancer patients with invasive, non-metastatic breast cancer with tumor material available for immunohistochemical determination of Ki67, EGFR, CK5/6 and HER-2 were included. ER and PR expression was retrieved from the pathology report. Molecular subtypes were: Luminal A, Luminal B, ERBB2, Basal-like and Unclassified. Primary endpoint was Relapse Free Period (RFP), taking into account the competing risk of mortality, and adjusted for the most important patient, tumor and treatment characteristics. Secondary endpoint was Relative Survival (RS).

RESULTS

Overall, 1362 patients were included. Patients with a Luminal A subtype had the lowest risk of recurrence (11% at 5 yrs). Patients with a Basal (24% at 5yrs) or ERBB2 (34% at 5yrs) molecular breast tumor subtype had the highest risk of recurrence. The ERBB2 subtype had the worst prognosis in terms of RFP (SHR 2.07, 95% CI 1.35-3.20; p = 0.001). The worst RS was again observed for the ERBB2 subtype (48% at 10 yrs). In multivariable analyses, the relative excess risk of death for all molecular subtypes was significantly worse compared to the Luminal A subtype.

CONCLUSION

Molecular intrinsic breast tumor subtypes have significant prognostic value in the elderly population, even after taking competing mortality into account.

Genetic variants in ANCA-associated vasculitis: a meta-analysis

BACKGROUND

Genetic factors may influence the pathogenic pathways leading to antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). We performed a meta-analysis to determine the genetic variants most likely associated with AAV and investigated whether diagnostic and serological subtypes within AAV have distinct genetic backgrounds.

METHODS

Studies investigating the association between genetic variants and AAV in humans were searched in PubMed, EMBASE and Web of Science. All variants investigated in at least two studies were selected. Subsequently, all studies assessing these variants were included in this meta-analysis. Additionally, data on these variants from the largest genome-wide association studies in AAV were included to increase the validity of this meta-analysis.

RESULTS

The literature search yielded 5180 articles. 62 articles investigating 140 genetic variants were included, 33 of which were associated with AAV in a meta-analysis. These genetic variants were in or near the following genes: CD226, CTLA-4, FCGR2A, HLA-B, HLA-DP, HLA-DQ, HLA-DR, HSD17B8, IRF5, PTPN22, RING1/RXRB, RXRB, STAT4, SERPINA1 and TLR9. Moreover, we identified genetic distinctions between granulomatosis with polyangiitis and microscopic polyangiitis and between proteinase 3 ANCA vasculitis and myeloperoxidase ANCA vasculitis. In 76% of the genetic variants, subdivision based on ANCA serotype resulted in higher ORs than subdivision based on clinical diagnosis.

CONCLUSIONS

This meta-analysis identified 33 genetic variants associated with AAV, supporting a role for alpha-1-antitrypsin, the major histocompatibility complex system, and several distinct inflammatory processes in AAV pathogenesis. Our results indicate that subdivision of AAV based on ANCA serotype has a stronger genetic basis than subdivision based on clinical diagnosis.

Sex specific association between carnosinase gene CNDP1 and cardiovascular mortality in patients with type 2 diabetes (ZODIAC-22)

INTRODUCTION

Homozygosity for a 5-leucine repeat (5L-5L) in the carnosinase gene (CNDP1) has been associated with a reduced prevalence of diabetic nephropathy in cross-sectional studies in patients with type 2 diabetes, particularly in women. Prospective studies on mortality are not available. This study investigated whether 5L-5L was associated with mortality and progression of renal function loss and to what extent this effect is modified by sex.

METHODS

In a prospective cohort of patients with type 2 diabetes, a Cox proportional hazard model was used to compare 5L-5L with other genotypes regarding (cardiovascular) mortality. Renal function slopes were obtained by within-individual linear regression of the estimated glomerular filtration rate (eGFR) using the Modification of Diet in Renal Disease (MDRD) equation, and were compared between 5L-5L and other genotypes.

RESULTS

871 patients were included (38% with 5L-5L). After 9.5 years of follow-up, hazards ratios (HR) for all-cause and cardiovascular mortality in 5L-5L versus other genotypes were 1.09 [95% confidence interval (CI) 0.88-1.36] and 1.12 (95% CI 0.79-1.58), respectively. There was a significant interaction between CNDP1 and sex for the association with cardiovascular mortality (p = 0.01), not for all-cause mortality (p = 0.32). Adjusted HR in 5L-5L for cardiovascular mortality was 0.69 (95% CI 0.39-1.23) in men and 1.77 (95% CI 1.12-2.81) in women. The slopes of eGFR-MDRD did not significantly differ between 5L-5L and other genotypes.

CONCLUSIONS

The association between CNDP1 and cardiovascular mortality was sex-specific, with a higher risk in women with 5L-5L genotype. CNDP1 was not associated with all-cause mortality or change in eGFR.

Genetic associations in diabetic nephropathy: a meta-analysis

AIMS/HYPOTHESIS

This meta-analysis assessed the pooled effect of each genetic variant reproducibly associated with diabetic nephropathy.

METHODS

PubMed, EMBASE and Web of Science were searched for articles assessing the association between genes and diabetic nephropathy. All genetic variants statistically associated with diabetic nephropathy in an initial study, then independently reproduced in at least one additional study, were selected. Subsequently, all studies assessing these variants were included. The association between these variants and diabetic nephropathy (defined as macroalbuminuria/proteinuria or end-stage renal disease [ESRD]) was calculated at the allele level and the main measure of effect was a pooled odds ratio. Pre-specified subgroup analyses were performed, stratifying for type 1/type 2 diabetes mellitus, proteinuria/ESRD and ethnic group.

RESULTS

The literature search yielded 3,455 citations, of which 671 were genetic association studies investigating diabetic nephropathy. We identified 34 replicated genetic variants. Of these, 21 remained significantly associated with diabetic nephropathy in a random-effects meta-analysis. These variants were in or near the following genes: ACE, AKR1B1 (two variants), APOC1, APOE, EPO, NOS3 (two variants), HSPG2, VEGFA, FRMD3 (two variants), CARS (two variants), UNC13B, CPVL and CHN2, and GREM1, plus four variants not near genes. The odds ratios of associated genetic variants ranged from 0.48 to 1.70. Additional variants were detected in subgroup analyses: ELMO1 (Asians), CCR5 (Asians) and CNDP1 (type 2 diabetes).

CONCLUSIONS/INTERPRETATION

This meta-analysis found 24 genetic variants associated with diabetic nephropathy. The relative contribution and relevance of the identified genes in the pathogenesis of diabetic nephropathy should be the focus of future studies.

Association between CNDP1 genotype and diabetic nephropathy is sex specific

OBJECTIVE

The 5-5 homozygous CNDP1 (carnosinase) genotype is associated with a reduced risk of diabetic nephropathy. We investigated whether this association is sex specific and independent of susceptibility for type 2 diabetes.

RESEARCH DESIGN AND METHODS

Three separate groups of 114, 90, and 66 patients with type 2 diabetes and diabetic nephropathy were included in this study and compared with 93 patients with type 2 diabetes for >15 years without diabetic nephropathy and 472 population control subjects. The diabetes control group was used to determine an association in the three patient groups separately, and the population control group was used to estimate the genotype risk [odds ratio (CI)] for the population in a pooled analysis. The population control subjects were also compared with 562 patients with type 2 diabetes without diabetic nephropathy to determine whether the association was independent of type 2 diabetes. The CNDP1 genotype was determined by fragment analysis after PCR amplification.

RESULTS

The frequency of the 5-5 homozygous genotype was 28, 36, and 41% in the three diabetic nephropathy patient groups and 43 and 42% in the diabetic and population control subjects, respectively. The 5-5 homozygous genotype occurred significantly less frequently in women in all three patient groups compared with diabetic control subjects. The genotype risk for the population was estimated to be 0.5 (0.30-0.68) in women and 1.2 (0.77-1.69) in men. The 562 patients with type 2 diabetes without diabetic nephropathy did not differ from the general population (P = 0.23).

CONCLUSIONS

This study suggests that the association between the CNDP1 gene and diabetic nephropathy is sex specific and independent of susceptibility for type 2 diabetes.

Pathologic classification of diabetic nephropathy

Although pathologic classifications exist for several renal diseases, including IgA nephropathy, focal segmental glomerulosclerosis, and lupus nephritis, a uniform classification for diabetic nephropathy is lacking. Our aim, commissioned by the Research Committee of the Renal Pathology Society, was to develop a consensus classification combining type1 and type 2 diabetic nephropathies. Such a classification should discriminate lesions by various degrees of severity that would be easy to use internationally in clinical practice. We divide diabetic nephropathy into four hierarchical glomerular lesions with a separate evaluation for degrees of interstitial and vascular involvement. Biopsies diagnosed as diabetic nephropathy are classified as follows: Class I, glomerular basement membrane thickening: isolated glomerular basement membrane thickening and only mild, nonspecific changes by light microscopy that do not meet the criteria of classes II through IV. Class II, mesangial expansion, mild (IIa) or severe (IIb): glomeruli classified as mild or severe mesangial expansion but without nodular sclerosis (Kimmelstiel-Wilson lesions) or global glomerulosclerosis in more than 50% of glomeruli. Class III, nodular sclerosis (Kimmelstiel-Wilson lesions): at least one glomerulus with nodular increase in mesangial matrix (Kimmelstiel-Wilson) without changes described in class IV. Class IV, advanced diabetic glomerulosclerosis: more than 50% global glomerulosclerosis with other clinical or pathologic evidence that sclerosis is attributable to diabetic nephropathy. A good interobserver reproducibility for the four classes of DN was shown (intraclass correlation coefficient = 0.84) in a test of this classification.

Lower frequency of the 5/5 homozygous CNDP1 genotype in South Asian Surinamese

We investigated the frequency of the 5/5 homozygous CNDP1 (carnosinase) genotype, which was found to be associated with a reduced risk of developing diabetic nephropathy, in three ethnic groups in The Netherlands. Particularly interesting were the South Asian Surinamese, who have a high prevalence of diabetic nephropathy. Furthermore, we investigated the association between this gene and carnosinase activity in South Asian Surinamese and whether carnosinase was expressed in the kidney. We genotyped 290 South Asian Surinamese, 532 African Surinamese, and 472 White Dutch in a cross-sectional population study. Furthermore, an independent cohort of South Asian Surinamese was genotyped. In this population, carnosinase activity was measured in serum. Immunostaining and in situ hybridization for CNDP1 were performed on kidney tissue. Both South Asian populations had lower frequencies of the 5/5 homozygous genotype than African Surinamese and White Dutch (23.0%, 27.2%, 38.2%, and 41.3%, respectively; chi-square, p<0.001). This genotype showed a lower carnosinase activity in South Asian Surinamese (Wilcoxon rank-sum, p=0.03). CNDP1 was expressed in the kidney. South Asian Surinamese have a lower frequency of the 5/5 homozygous genotype, which was associated with lower carnosinase activity. Our study provides an indication that South Asian Surinamese are genetically at risk for developing diabetic nephropathy.