No abstract

A djuvant immune checkpoint inhibition (CPI) and BRAF/ MEK-targeted therapies after therapeutic lymph node dissection (TLND) have improved relapse-free survival (RFS) in patients with clinical stage III nodal melanoma. Despite these improvements, approximately 40-50% of patients have a relapse within 3-5 years after TLND 1-3 . Preclinical and early clinical trial data suggest that neoadjuvant CPI leads to superior anti-tumor immunity and survival benefit compared to adjuvant CPI 4,5 . Similarly to stage IV melanoma, the combination of anti-CLTA-4 and anti-PD-1 appears to be superior to anti-PD-1 monotherapy in the neoadjuvant setting 6,7 . Previous clinical trials (OpACIN (NCT02437279) and OpACIN-neo (NCT02977052)) testing neoadjuvant ipilimumab (anti-CTLA-4) plus nivolumab (anti-PD-1) in stage III melanoma demonstrated high pathologic response rates (pRRs; 74-78%) and a strong association between pathologic response and RFS, with 94-100% of responding patients remaining free of relapse at 2 years 5,7-9 . Similarly, long-term benefit was observed upon complete response to CPI in stage IV melanoma, even after cessation of CPI [10][11][12] .The association between response and survival; the observed ongoing responses after cessation of therapy in stage IV melanoma; and the substantial morbidity from TLND [13][14][15][16] that impairs

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 antiprogrammed 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 ¼ 29), cellular composition of the tumour bed was analysed by flow cytometry. Results: There was strong interobserver reproducibility in assessment of pathological response (k ¼ 0.879) and percentage residual viable melanoma (intraclass correlation coefficient ¼ 0.965). The immunotherapeutic response subtype with high fibrosis had the strongest association with lack of recurrence (P ¼ 0.008) and prolonged RFS (P ¼ 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 ¼ 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 ¼ 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.

Ductal carcinoma in situ (DCIS) is considered a potential precursor of invasive breast carcinoma (IBC). Studies aiming to find markers involved in DCIS progression generally have compared characteristics of IBC lesions with those of adjacent synchronous DCIS lesions. The question remains whether synchronous DCIS and IBC comparisons are a good surrogate for primary DCIS and subsequent IBC. In this study, we compared both primary DCIS and synchronous DCIS with the associated IBC lesion, on the basis of immunohistochemical marker expression. Immunohistochemical analysis of ER, PR, HER2, p53, and cyclo-oxygenase 2 (COX-2) was performed for 143 primary DCIS and subsequent IBC lesions, including 81 IBC lesions with synchronous DCIS. Agreement between DCIS and IBC was assessed using kappa, and symmetry tests were performed to assess the pattern in marker conversion. The primary DCIS and subsequent IBC more often showed discordant marker expression than synchronous DCIS and IBC. Strikingly, 18 of 49 (36%) women with HER2-positive primary DCIS developed an HER2-negative IBC. Such a difference in HER2 expression was not observed when comparing synchronous DCIS and IBC. The frequency of discordant marker expression did not increase with longer time between primary DCIS and IBC. In conclusion, comparison of primary DCIS and subsequent IBC yields different results than a comparison of synchronous DCIS and IBC, in particular with regard to HER2 status. To gain more insight into the progression of DCIS to IBC, it is essential to focus on the relationship between primary DCIS and subsequent IBC, rather than comparing IBC with synchronous DCIS.

Ductal carcinoma (DCIS) is treated to prevent progression to invasive breast cancer. Yet, most lesions will never progress, implying that overtreatment exists. Therefore, we aimed to identify factors distinguishing harmless from potentially hazardous DCIS using a nested case-control study. We conducted a case-control study nested in a population-based cohort of patients with DCIS treated with breast-conserving surgery (BCS) alone ( = 2,658) between 1989 and 2005. We compared clinical, pathologic, and IHC DCIS characteristics of 200 women who subsequently developed ipsilateral invasive breast cancer (iIBC; cases) and 474 women who did not (controls), in a matched setting. Median follow-up time was 12.0 years (interquartile range, 9.0-15.3). Conditional logistic regression models were used to assess associations of various factors with subsequent iIBC risk after primary DCIS. High COX-2 protein expression showed the strongest association with subsequent iIBC [OR = 2.97; 95% confidence interval (95% CI), 1.72-5.10]. In addition, HER2 overexpression (OR = 1.56; 95% CI, 1.05-2.31) and presence of periductal fibrosis (OR = 1.44; 95% CI, 1.01-2.06) were associated with subsequent iIBC risk. Patients with HER2/COX-2 DCIS had a 4-fold higher risk of subsequent iIBC (vs. HER2/COX-2 DCIS), and an estimated 22.8% cumulative risk of developing subsequent iIBC at 15 years. With this unbiased study design and representative group of patients with DCIS treated by BCS alone, COX-2, HER2, and periductal fibrosis were revealed as promising markers predicting progression of DCIS into iIBC. Validation will be done in independent datasets. Ultimately, this will aid individual risk stratification of women with primary DCIS. .