Comparison of model fit and discriminatory ability of M category as defined by the 7th and 8th editions of the tumor-node-metastasis classification of colorectal cancer and the 9th edition of the Japanese classification.

BACKGROUND: In transitioning from the 7th edition of the tumor-node-metastasis classification (TNM-7) to the 8th edition (TNM-8), colorectal cancer with peritoneal metastasis was newly categorized as M1c. In the 9th edition of the Japanese Classification of colorectal, appendiceal, and anal carcinoma (JPC-9), M1c is further subdivided into M1c1 (without other organ involvement) and M1c2 (with other organ involvement). This study aimed to compare the model fit and discriminatory ability of the M category of these three classification systems, as no study to date has made this comparison. METHODS: The study population consisted of stage IV colorectal cancer patients who were referred to the National Cancer Center Hospital from 2000 to 2017. The Akaike information criterion (AIC), Harrell's concordance index (C-index), and time-dependent receiver operating characteristic (ROC) curves were used to compare the three classification systems. Subgroup analyses, stratified by initial treatment year, were also performed. RESULTS: According to TNM-8, 670 (55%) patients had M1a, 273 (22%) had M1b, and 279 (23%) had M1c (87 M1c1 and 192 M1c2 using JPC-9) tumors. Among the three classification systems, JPC-9 had the lowest AIC value (JPC-9: 10546.3; TNM-7: 10555.9; TNM-8: 10585.5), highest C-index (JPC-9: 0.608; TNM-7: 0.598; TNM-8: 0.599), and superior time-dependent ROC curves throughout the observation period. Subgroup analyses were consistent with these results. CONCLUSIONS: While the revised M category definition did not improve model fit and discriminatory ability from TNM-7 to TNM-8, further subdivision of M1c in JPC-9 improved these parameters. These results support further revisions to M1 subcategories in future editions of the TNM classification system.

The 2019 World Health Organization Classification of appendiceal, colorectal and anal canal tumours: an update and critical assessment.

The recently published 5th edition 2019 World Health Organization (WHO) Classification of Tumours of the Digestive System brings significant changes from the 2010 4th edition. An emphasis on uniformity in nomenclature and grading for tumours across all organ systems is a particular feature of the 5th edition blue book series that is reflected in the gastrointestinal tract (GIT) classification. For example, simplified two tiered grading is reinforced for preinvasive lesions throughout the GIT, with dysplasia at all sites now being considered either low or high grade. Similarly, a uniform approach to classification and grading of GIT neuroendocrine neoplasms has been consolidated, with an emphasis on distinguishing grade 3 neuroendocrine tumours from neuroendocrine carcinomas. In this review, we discuss and critically assess the important and sometimes controversial changes made to the classification of tumours of the lower GIT, comprising the colorectum, vermiform appendix and anal canal. The particularly controversial decision to endorse the term 'sessile serrated lesion' for lesions previously termed 'sessile serrated polyp/adenoma' is explored. The morphological, molecular, and clinical insights behind the substitution of the term 'goblet cell adenocarcinoma' for 'goblet cell carcinoid' are assessed. The evolution of the classification of appendiceal mucinous neoplasms is considered. Inflammatory bowel disease related dysplasia and its evolving subtypes, with major implications for pathologists in routine practice, is explained.

Classifying Anal Intraepithelial Neoplasia 2 Based on LAST Recommendations.

OBJECTIVES: The Lower Anogenital Squamous Terminology (LAST) recommendations classify human papillomavirus-associated squamous lesions into low- and high-grade squamous intraepithelial lesions (LSILs/HSILs). Our study aimed to assess interobserver agreement among 6 experienced pathologists in assigning 40 anal lesions previously diagnosed as anal intraepithelial neoplasia 2 (AIN 2) to either HSIL or non-HSIL categories. METHODS: Agreement based on photomicrographs of H&E alone or H&E plus p16 immunohistochemistry was calculated using κ coefficients. RESULTS: Agreement was fair based on H&E alone (κ = 0.42; 95% confidence interval [CI], 0.34-0.52). Adding p16 improved agreement to moderate (κ = 0.55; 95% CI, 0.54-0.62). On final diagnosis, 21 cases (53%) had unanimous diagnoses, and 19 (47%) were divided. When designating p16 results as positive or negative, agreement was excellent (κ = 0.92; 95% CI, 0.83-0.95). Among variables (staining location, extent, and intensity), staining of the basal/parabasal layers was a consistent feature in cases with consensus for positive results (20/20). Of the 67 H&E diagnoses with conflicting p16 results, participants modified 32 (48%), downgrading 23 HSILs and upgrading 9 non-HSILs. CONCLUSIONS: Although p16 increased interobserver agreement, disagreement remained considerable regarding intermediate lesions. p16 expression, particularly if negative, can reduce unwarranted HSIL diagnoses and unnecessary treatment.

Genetic Profile and Functional Proteomics of Anal Squamous Cell Carcinoma: Proposal for a Molecular Classification.

Anal squamous cell carcinoma is a rare tumor. Chemo-radiotherapy yields a 50% 3-year relapse-free survival rate in advanced anal cancer, so improved predictive markers and therapeutic options are needed. High-throughput proteomics and whole-exome sequencing were performed in 46 paraffin samples from anal squamous cell carcinoma patients. Hierarchical clustering was used to establish groups de novo Then, probabilistic graphical models were used to study the differences between groups of patients at the biological process level. A molecular classification into two groups of patients was established, one group with increased expression of proteins related to adhesion, T lymphocytes and glycolysis; and the other group with increased expression of proteins related to translation and ribosomes. The functional analysis by the probabilistic graphical model showed that these two groups presented differences in metabolism, mitochondria, translation, splicing and adhesion processes. Additionally, these groups showed different frequencies of genetic variants in some genes, such as ATM, SLFN11 and DST Finally, genetic and proteomic characteristics of these groups suggested the use of some possible targeted therapies, such as PARP inhibitors or immunotherapy.

Introducing the eighth edition of the tumor-node-metastasis classification as relevant to colorectal cancer, anal cancer and appendiceal cancer: a comparison study with the seventh edition of the tumor-node-metastasis and the Japanese Classification of Colorectal, Appendiceal, and Anal Carcinoma.

BACKGROUND: The eighth edition of the tumor-node-metastasis classification of malignant tumors updates cancer staging according to the evidence accumulated in the last 8 years since the release of the tumor-node-metastasis seventh edition. This review focuses on the new staging system. METHODS: The eight edition was compared with the seventh edition as well as the Japanese Classification of Colorcetal, Appendiceal, and Anal carcinoma ninth edition. RESULTS: Of colon and rectum, the tumor-node-metastasis eighth edition expands the M category. Specifically, colorectal cancer with peritoneal metastasis is newly categorized as M1c, distinguishing it from M1a (metastasis to one organ) and M1b (metastasis to more than one organ). In the ninth edition of Japanese Classification of Colorectal, Appendiceal, and Anal Carcinoma, M1c is further subdivided into M1c1 (metastasis to the peritoneum without other organ involvement) and M1c2 (metastasis to the peritoneum with other organ involvement). In the T category, the tumor-node-metastasis eighth edition excludes high-grade dysplasia (intraepithelial carcinoma) from Tis; this differs from both the tumor-node-metastasis seventh edition and the Japanese Classification of Colorectal, Appendiceal, and Anal Carcinoma ninth edition. In the N category, the tumor-node-metastasis eighth edition does not add the number of tumor deposits to the number of positive regional lymph nodes, whereas this number is added in the Japanese Classification of Colorectal, Appendiceal, and Anal Carcinoma ninth edition. The definition of anal cancer is also modified considerably in the tumor-node-metastasis eighth edition; specifically, tumors of perianal skin defined as within 5 cm of the anal margin are also classified as anal canal carcinoma, external iliac lymph nodes become regional lymph nodes, and both N2 and N3 are abolished in the N category. With regard to appendix, Tis (low-grade appendiceal mucinous neoplasma) and tumor deposit(s) are newly introduced. Finally, the tumor-node-metastasis eighth edition offers a new structure, labeled a 'prognostic factors grid', which consists of prognostic factors for survival in both colorectal and anal cancer. CONCLUSIONS: Staging classification is updated regularly, which clinicians should always catch up with.

Anal Neoplasia in Inflammatory Bowel Disease: Classification Proposal, Epidemiology, Carcinogenesis, and Risk Management Perspectives.

Patients with inflammatory bowel disease [IBD] may develop, similarly to individuals from general population, rare cases of human papilloma virus [HPV]-related anal canal squamous cell carcinoma [SCC] and intra-epithelial precursor lesions, as well as very rare cases of anal canal adenocarcinoma. Patients with chronic perianal Crohn's disease [CD] are at substantial risk of developing SCC or adenocarcinoma from the fistula-lining epithelium, as well as SCC or adenocarcinoma arising from chronic anorectal ulcerations or strictures. Based on this lesion stratification, we provide in this review tailored incidence estimates and we propose an IBD-specific classification of all types of anal neoplasia that may occur in patients with IBD. After reviewing putative carcinogenesis of all types of neoplasia, we conclude that HPV vaccination could reduce the incidence of HPV-related lesions, although an anal screening programme related to these lesions is not mandatory on the sole basis of IBD. By contrast, we point out that all patients with chronic perianal CD should be explored in depth, including biopsies under anaesthesia and fistula curettage when necessary, in case of any change in anal symptoms ─in particular new, increasing, unexplained pain. Finally, we conclude that there is an urgent need for elaborating and evaluating surveillance algorithms in patients with chronic perianal CD, in order to avoid cancers with late diagnosis and poor prognosis.

Proteomic signatures reveal a dualistic and clinically relevant classification of anal canal carcinoma.

Aetiologically linked to HPV infection, malignancies of the anal canal have substantially increased in incidence over the last 20 years. Although most anal squamous cell carcinomas (SCCs) respond well to chemoradiotherapy, about 30% of patients experience a poor outcome, for undetermined reasons. Despite cumulative efforts for discovering independent predictors of overall survival, both nodal status and tumour size are still the only reliable factors predicting patient outcome. Recent efforts have revealed that the biology of HPV-related lesions in the cervix is strongly linked to the originally infected cell population. To address the hypothesis that topography also influences both gene expression profile and behaviour of anal (pre)neoplastic lesions, we correlated both proteomic signatures and clinicopathological features of tumours arising from two distinct portions of the anal canal: the lower part (squamous zone) and the more proximal anal transitional zone. Although microdissected cancer cells appeared indistinguishable by morphology (squamous phenotype), unsupervised clustering analysis of the whole proteome significantly highlighted the heterogeneity that exists within anal canal tumours. More importantly, two region-specific subtypes of SCC were revealed. The expression profile (sensitivity/specificity) of several selected biomarkers (keratin filaments) further confirmed the subclassification of anal (pre)cancers based on their cellular origin. Less commonly detected compared to their counterparts located in the squamous mucosa, SCCs originating in the transitional zone more frequently displayed a poor or basaloid differentiation, and were significantly correlated with reduced disease-free and overall survivals. Taken together, we present direct evidence that anal canal SCC comprises two distinct entities with different cells of origin, proteomic signatures, and survival rates. This study forms the basis for a dualistic classification of anal carcinoma, with implications for management, outcome expectations, and possibly therapy. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Utility of Human Papillomavirus Capsid Protein L1 and p16 in the Assessment and Accurate Classification of Anal Squamous Intraepithelial Lesions.

OBJECTIVES: Morphologic evaluation of anal dysplasia remains problematic, especially in cases with limited biopsy samples or obscuring inflammation. Studies in cervical neoplasia have shown that human papillomavirus (HPV) L1 capsid production is highest in low-grade squamous intraepithelial lesions (LSILs) and progressively decreases in high-grade squamous intraepithelial lesions (HSILs). The combined utility of HPV L1 and p16 expression in assessing anal squamous intraepithelial lesions (SILs) has never been analyzed and forms the basis of this study. METHODS: In total, 145 anal lesions were reviewed and immunohistochemically stained for HPV L1 and p16. p16 expression was recorded as negative, patchy/focal, or diffuse. For analytical purposes, condylomas were evaluated separately from rest of the LSILs. RESULTS: There were 34 (23%) condylomas, 64 (44%) LSILs, and 47 (32%) HSILs. HPV L1 was significantly associated with condylomas (68%) and LSILs (52%) compared with HSILs (9%; P < .0001). Diffuse p16 staining was present only in HSILs (P < .0001), whereas a patchy/focal p16 staining pattern was observed in both LSILs and condylomas. CONCLUSIONS: HPV L1 and diffuse p16 expression is mutually exclusive in most anal SILs and helps separate LSIL and HSIL cases. Application of both HPV L1 and p16 can not only facilitate accurate grading but also contribute to risk assessment in anal neoplasia.

The LAST Project and the diagnostic bottom line.

The LAST Project's consensus recommendations for terminology and biomarker use to improve the accuracy and reproducibility of histopathological diagnoses for HPV-associated squamous intraepithelial lesions of the lower anogenital tract are reviewed.

Malignancies of the anal canal: a multi-center retrospective analysis in South China population.

PURPOSE: Malignancies of the anal canal are rare diseases associated with limited reports and insufficient data. The purpose of this study was to evaluate the spectrum of pathological subtypes, therapeutic modalities and prognosis of patients in the Chinese population with anal canal malignancies. METHODS: A retrospective consecutive series of patients with malignancies of the anal canal at 4 institutions in China between January 1990 and December 2011 was studied. The patient demographic data, including age, gender, tumor stage, initial symptoms, pathological diagnosis, treatment and survival, were collected and analyzed from the hospitals' databases. RESULTS: A total of 180 patients (90 males, 90 females) with anal canal malignancies was identified. Their median age was 58 years (range 17-88). The 3 most common pathological subtypes were adenocarcinoma (N-129, 71.7%), squamous cell carcinoma (SCC; N=21, 11.7%) and melanoma (N7equals;15, 8.3%). Ninety-five adenocarcinoma patients and 10 SCC patients were managed with abdominoperineal resection (APR). With a median follow-up time of 28.9 months (range 1-173), the 5-year overall survival (OS) rates for all patients, adenocarcinoma patients, SCC patients and melanoma patients were 41.9, 40.6, 44.5 and 14.8% respectively, and the median OS time were 46.8, 50.1, 52.5 and 25.0 months, respectively (p=0.173). CONCLUSION: Adenocarcinoma was the major histological subtype in Chinese patients with anal canal malignancies. APR-based combined modality treatment was the first choice for the past two decades, whereas multidisciplinary treatment was not performed adequately. The management of SCC must be standardized in South China population. In the future, randomized clinical trials are warranted for the optimal treatment options of anal canal adenocarcinoma patients.

The reporting of anal cytology and histology samples: establishing terminology and criteria.

Our understanding of the human papillomavirus (HPV) related cytomorphology and histopathology of the anal canal is underpinned by our knowledge of HPV infection in the cervix. In this review, we utilise cervical reporting of cytological and histological specimens as a foundation for the development of standardised and evidence-based terminology and criteria for reporting of anal specimens. We advocate use of the Australian Modified Bethesda System 2004 for reporting anal cytology. We propose the use of a two-tiered histological reporting system for noninvasive disease - low-grade and high-grade anal intraepithelial neoplasia. These classification systems reflect current understanding of the biology of HPV and enhance diagnostic reproducibility. Biomarkers such as p16(INK4A) may prove useful in further improving diagnostic accuracy. Standardisation is important because it will increase the value of the data collected as Australian centres develop programs for screening for anal neoplasia.

The Lower Anogenital Squamous Terminology Standardization Project for HPV-Associated Lesions: background and consensus recommendations from the College of American Pathologists and the American Society for Colposcopy and Cervical Pathology.

The terminology for human papillomavirus(HPV)­associated squamous lesions of the lower anogenital tract has a long history marked by disparate diagnostic terms derived from multiple specialties. It often does not reflect current knowledge of HPV biology and pathogenesis. A consensus process was convened to recommend terminology unified across lower anogenital sites. The goal was to create a histopathologic nomenclature system that reflects current knowledge of HPV biology, optimally uses available biomarkers, and facilitates clear communication across different medical specialties. The Lower Anogenital Squamous Terminology (LAST) Project was co-sponsored by the College of American Pathologists and the American Society for Colposcopy and Cervical Pathology and included 5 working groups; 3 work groups performed comprehensive literature reviews and developed draft recommendations. Another work group provided the historical background and the fifth will continue to foster implementation of the LAST recommendations. After an open comment period, the draft recommendations were presented at a consensus conference attended by LAST work group members, advisors, and representatives from 35 stakeholder organizations including professional societies and government agencies. Recommendations were finalized and voted on at the consensus meeting. The final, approved recommendations standardize biologically relevant histopathologic terminology for HPV-associated squamous intraepithelial lesions and superficially invasive squamous carcinomas across all lower anogenital tract sites and detail the appropriate use of specific biomarkers to clarify histologic interpretations and enhance diagnostic accuracy. A plan for disseminating and monitoring recommendation implementation in the practicing community was also developed. The implemented recommendations will facilitate communication between pathologists and their clinical colleagues and improve accuracy of histologic diagnosis with the ultimate goal of providing optimal patient care.

[Squamous cell carcinoma of the anal canal showing complete response following chemoradiotherapy--a case report].

We report a case of squamous cell carcinoma of the anal canal which showed complete response following chemoradiotherapy. A 54-year-old woman was diagnosed as having squamous cell carcinoma of the anal canal (T2N0M0 stage II). Chemoradiotherapy comprising peroral tegafur/uracil and external radiotherapy (60 Gy) to the pelvic space resulted in complete response 4 months after the initiation of the treatment. PET-CT showed recurrence in paraortic lymph node, right sacral and left pubic bone 11 months after the initiation of treatment, although the primary lesion did not relapse. The patient is now given 5-fluorouracil/cisplatin in addition to external radiotherapy (57.5 Gy) to the metastatic lymph node. This case suggests that we should take measures to prevent distant metastases in the treatment of squamous cell carcinoma of the anal canal.

Extra-oral plasmablastic lymphoma: report of a case and review of literature.

Plasmablastic lymphoma (PBL) of the oral cavity is classified as one subtype of diffuse large B-cell lymphoma that is most commonly seen in patients with human immunodeficiency virus infection. We report a rare case of PBL in the anal canal of a 33-year-old man with human immunodeficiency virus infection. The lymphoma cells were positive for CD138 and weakly positive for CD79a. In addition, these cells were also positive for CD10. The neoplastic cells were positive for Epstein-Barr virus and negative for human herpes virus 8. Review of the English medical literature revealed many more cases of extra-oral PBL. We propose that the term plasmablastic lymphoma of the oral cavity in World Health Organization classification be revised to simply plasmablastic lymphoma, which would include both oral and extra-oral PBLs, and the term to define the primary site of the lymphoma (ie, oral cavity) be dropped from the terminology used in World Health Organization classification.