BRIEF REPORT Pathologist second opinion significantly alters clinical management of pT1 endoscopically resected colorectal cancer Gian Luca Rampioni Vinciguerra 1,2 & Giulio Antonelli 3 & Francesca Citron 2 & Giammauro Berardi 3 & Stefano Angeletti 3 & Gustavo Baldassarre 2 & Andrea Vecchione 1 & Emilio Di Giulio 3 & Emanuela Pilozzi 1 Received: 10 April 2019 /Revised: 31 May 2019 /Accepted: 6 June 2019 # Springer-Verlag GmbH Germany, part of Springer Nature 2019 Abstract We retrospectively collected a series of 82 endoscopically removed early colorectal cancers. Histological specimens were revised by two gastrointestinal pathologists, performing a re-evaluation of all risk factors for lymph node metastasis. The comparison between second opinion and first pathological report revealed that lymphovascular invasion and tumor grading showed a lower level of concordance than other parameters. Our results demonstrated that second opinion modified risk assessment in about 10% of cases. It was mainly due to a lack in reporting of some parameters at the first diagnosis and a different evaluation in second opinion for updated guidelines. Considering the subgroup of patients with modified risk assessment, clinical data revealed that tumors, re-classified as low risk, did not develop lymph node metastasis that, conversely, occurred in patients identified as high risk by second opinion. In conclusion, second opinion significantly alters risk perception of endoscopically removed early colorectal carcinomas representing a valuable tool for their appropriate clinical management. Keywords Colorectal carcinoma . Prognostic factors . Second opinion . Early colorectal carcinoma . Lymph node metastasis Introduction Worldwide implementation of colorectal cancer (CRC) screening programs has significantly increased the percentage of tumors endoscopically treated at early stage, and this amount is expected to rise [1]. Early CRC (eCRC) is classified as pT1 and defined by invasion limited to the submucosa [2]. In eCRC patients, en- doscopic resection showed to be safer than surgery, although lymph node metastasis (pN+) still occurs in 5–15% of cases limiting its success [3]. Many histological parameters have been proposed to stratify the pN+ risk and identify lesions that may ben- efit from additional surgical resection [3, 4]. Despite improvements in stratification and novel guidelines, an intrinsic variability in histological analyses, pN+ rates, and clinical management still exists [5], ascribed to the lack of standardization and inter-observer agreement in reporting risk factors [3]. Gastrointestinal pathology is recognized as a critical field attracting a high rate of diagnostic mistakes and discordances. Thus, a second opinion has been proposed to minimize possi- ble misdiagnosis [6]. However, second opinion is rarely re- ported, although European CRC screening Guidelines suggest its employment, especially when a surgical resection is con- sidered [7]. Our aim was to assess how a second opinion affects clinical management of endoscopically resected eCRC and which histological risk factors are mostly influenced. Gian Luca Rampioni Vinciguerra and Giulio Antonelli contributed equally to this work. Electronic supplementary material The online version of this article (https://doi.org/10.1007/s00428-019-02603-y) contains supplementary material, which is available to authorized users. * Gian Luca Rampioni Vinciguerra gianluca.rampionivinciguerra@uniroma1.it 1 Faculty of Medicine and Psychology, Department of Clinical and Molecular Medicine, University of Rome BSapienza^, Santo Andrea Hospital, via di Grottarossa 1035, 00189 Rome, Italy 2 Division of Molecular Oncology, Centro di Riferimento Oncologico di Aviano (CRO), IRCCS, National Cancer Institute, 33081 Aviano, Italy 3 Faculty of Medicine and Psychology, Department of Surgical and Medical Sciences and Translational Medicine, University of Rome BSapienza^, Santo Andrea Hospital, 00189 Rome, Italy https://doi.org/10.1007/s00428-019-02603-y Virchows Archiv (2019) 475:665–668 /Published online: 17 2019 June