A rational approach to postoperative surveillance for resected non-functional pancreatic neuro-endocrine tumours.

BACKGROUND: Non-functional pancreatic neuroendocrine tumours (NF-PNETs) are rare and have highly variable outcomes. Current guidelines recommend surveillance for NF-PNETs <2 cm. Patients who ultimately have surgical resection are at risk of disease recurrence, and data to support postoperative surveillance protocols are lacking. The aims of this study were to i) identify post-operative predictors of recurrence and ii) risk stratify patients at risk of recurrence. METHODS: Consecutive patients who underwent surgery for NF-PNETs between 2002 and 2015 were identified retrospectively. Data were collected on demographics, pre-operative laboratory results and histopathological tumour characteristics. Statistical analyses were based on penalised Cox-regression modelling and a decision-tree model. Comparison of the variables identified was performed using ROC curves to identify the most sensitive and specific variable associated with disease recurrence. RESULTS: We identified 73 patients (38 males) with a median age of 61.5 years (range: 31-79). The median period of follow-up was 49 months (5-131). During follow up, 10 deaths (13.9%) were recorded and disease recurrence occurred in 12 patients (16.4%). The Kaplan-Meier predicted 1-,3- and 5-year recurrence-free survival rates were 98.6% (95% CI = 95.9, 100%), 85.4% (76.9-94.8%) and 72% (58.7-88.2%) respectively. Cox multivariate analysis identified poor tumour differentiation (WHO G3 grade) and lymph node ratio (LNR) as independent predictors for recurrence (p < 0.05). A simple criterion of 'tumour grade G3 or LNR ≥0.1' was found to be sensitive and specific in detecting disease recurrence. CONCLUSION: Our results have identified a simple and sensitive criterion for risk stratifying post-resection surveillance. Prospective validation in larger patient cohort is now warranted.

Differential binding affinity of mutated peptides for MHC class I is a predictor of survival in advanced lung cancer and melanoma.

Background: Cancer mutations generate novel (neo-)peptides recognised by T cells, but the determinants of recognition are not well characterised. The difference in predicted class I major histocompatibility complex (MHC-I) binding affinity between wild-type and corresponding mutant peptides (differential agretopicity index; DAI) may reflect clinically relevant cancer peptide immunogenicity. Our aim was to explore the relationship between DAI, measures of immune infiltration and patient outcomes in advanced cancer. Patients and methods: Cohorts of patients with advanced non-small-cell lung cancer (NSCLC; LUAD, n = 66) and melanoma (SKCM, n = 72) were obtained from The Cancer Genome Atlas. Three additional cohorts of immunotherapy treated patients with advanced melanoma (total n = 131) and NSCLC (n = 31) were analysed. Neopeptides and their clonal status were defined using genomic data. MHC-I binding affinity was predicted for each neopeptide and DAI values summarised as the sample mean DAI. Correlations between mean DAI and markers of immune activity were evaluated using measures of lymphocyte infiltration and immune gene expression. Results: In univariate and multivariate analyses, mean DAI significantly correlated with overall survival in 3/5 cohorts, with evidence of superiority over nonsynonymous mutational and neoantigen burden. In these cohorts, the effect was seen for mean DAI of clonal but not subclonal peptides. In SKCM, the association between mean DAI and survival bordered significance (P = 0.068), reaching significance in an immunotherapy-treated melanoma cohort (P = 0.003). Mean DAI but not mutational nor neoantigen burden was positively correlated with independently derived markers of immune infiltration in both SKCM (P = 0.027) and LUAD (P = 0.024). Conclusions: The association between mean DAI, survival and measures of immune activity support the hypothesis that DAI is a determinant of cancer peptide immunogenicity. Investigation of DAI as a marker of immunologically relevant peptides in further datasets and future clinical studies of neoantigen based immunotherapies is warranted.

Intraplacental choriocarcinoma: Systematic review and management guidance.

BACKGROUND: Intraplacental choriocarcinoma (IC) is a rare form of malignant gestational trophoblastic disease (GTD). We present a review of 62 cases, including four previously unreported, and a suggested management algorithm. PATIENTS AND METHODS: IC cases and clinical data were identified within the Charing Cross Hospital (CXH) national GTD database (1986-2014) and by systematic literature search (1949-2014). RESULTS: 62 cases were identified including eight from CXH representing 0.03% of all GTD (n=27,101) diagnosed between 1986 and 2014. Most cases were identified in the third trimester (n=52; 84%) among asymptomatic women (n=31; 50%) and with macroscopically normal placenta in 29% (18/62). In 29 non-metastatic cases with available data, 4 (14%) underwent adjuvant chemotherapy and 25 (86%) surveillance only, one of whom relapsed with metastatic disease cured with multi-agent chemotherapy. In 32 patients with metastatic disease (31 at presentation and one with relapse during surveillance), all 18 treated since 1990 achieved complete remission with multi-agent chemotherapy. Among 58 cases with available data, there were 20 fetal deaths and 38 live births with 2 neonatal deaths. Of the two (5%) cases of infantile choriocarcinoma, one was cured with intensive therapy and the other died shortly after commencing single agent treatment. A further neonatal death was due to fetomaternal haemorrhage. CONCLUSIONS: IC usually occurs in the third trimester and is often asymptomatic with no macroscopic placental abnormalities. Prognosis with current therapy is generally excellent, even for patients presenting with metastatic disease. Around 60% of pregnancies affected by IC result in a live birth with a low neonatal mortality.

Treatment of metastatic placental site trophoblastic tumor with surgery, chemotherapy, immunotherapy and coil embolization of multiple pulmonary arteriovenous fistulate.

Placental Site Trophoblastic Tumor (PSTT) is a rare malignancy that often presents with extensive disease and can be resistant to traditional treatments. We present the case of a woman with stage IV PSTT who was initially managed with neoadjuvant chemotherapy followed by tumor debulking. Adjuvant therapy was guided by further pathologic analysis that revealed high levels of staining for PD-L1 as well as the presence of tumor infiltrating lymphocytes (TILs). Subsequently, the patient was treated with traditional chemotherapy with the EP/EMA regimen with the addition of pembrolizumab. The patient's treatment course was complicated by the development of pulmonary arteriovenous malformations, autoimmune thyroiditis thought to be secondary to immunotherapy, and significant tinnitus secondary to platinum agents. Currently the patient is in follow up and remains in a complete remission.