Evaluation of human papillomavirus (HPV) prediction using the International Endocervical Adenocarcinoma Criteria and Classification system, compared to p16 immunohistochemistry and HPV RNA in-situ hybridization

Incidence and Clinicopathologic Characteristics of Human Papillomavirus-independent Invasive Squamous Cell Carcinomas of the Cervix: A Morphologic, Immunohistochemical, and Human Papilloma-Virologic Study of 670 Cases

We aimed to determine the frequency of human papillomavirus-independent (HPVI) cervical squamous cell carcinoma (SCC) and to describe clinicopathologic characteristics. Among 670 patients with surgically treated SCCs in an established multi-institutional cohort, 447 had available tissue. Tissue microarrays were constructed and studied by in situ hybridization (ISH) for high-risk and low-risk human papillomavirus (HPV) mRNA and immunohistochemistry for p16 and p53. Tumors were HPVI if negative by HPV ISH and they failed to show diffuse p16 positivity by immunohistochemistry, and human papillomavirus-associated (HPVA) if positive by HPV ISH. Ten HPVI SCCs and 435 HPVA SCCs were identified; 2 cases were equivocal and excluded from analysis. The overall rate of HPVI SCC was low (2%) but was higher among older patients (7% in patients above 60 y of age and 17% in patients above 70 y of age). Compared with HPVA, patients with HPVI SCC were significantly older (median age, 72 vs. 49, P <0.001) and diagnosed at a higher stage (40% vs. 18% with stage III/IV disease, P =0.055). p53 expression was varied; 2 cases (20%) had null expression and 8 (80%) had wild-type expression. HPVI SCCs were heterogenous, with keratinizing, nonkeratinizing, and warty morphologies observed. Several cases had a precursor lesion reminiscent of differentiated vulvar intraepithelial neoplasia, with prominent basal atypia and hypereosinophilia or a basaloid-like morphology. Two patients (20%) had distant recurrences within 12 months, and 3 (30%) died of disease during follow-up. HPVI SCCs are rare tumors that are more common among older patients with higher stage disease and have important clinical and histologic differences from HPVA SCCs.

Joint detection of multiple HPV-testing technologies and evaluation of clinicopathological characteristics discriminate between HPV-independent and low-copy HPV-associated cervical squamous cell carcinoma (CSCC) -an analysis of 3869 cases

OBJECTIVES

This study aimed to investigate the frequency and clinicopathological characteristics of HPV-independent cervical squamous cell carcinoma (CSCC).

METHODS

A total of 3869 patients with CSCC from 2017 to 2021 were searched. p16^INK4a immunochemistry (IHC), two HPV-DNA(L1) polymerase chain reactions and HPV mRNA in situ hybridization were performed. Viral copies were detected using the 21 HPV quantitative test.

RESULTS

Six cases showed negative results in all four assays (group 1, 0.16%). Twenty-seven cases showed discordant results (group 2), and 3836 cases presented all-positive results (group 3). p16^INK4a IHC showed similar sensitivity, specificity, and positive predictive value compared to the other three direct HPV assays. 21 HPV genotyping showed 100% of negative predictive value. HPV copies were extremely lower in Group 2 than in Group 3 (P < 0.01), but were not significantly different from those in Group 1. Older age, advanced FIGO stage (III-IV) and abnormal p53 (p53abn) IHC were independent predictors of HPV-negative status in univariate and multivariate logistic regression. Group 2 had similar proportions of age >60 years and p53abn IHC with Group 1, but had fewer cases with advanced FIGO stage (P < 0.05) and TILs (P < 0.05). Groups 1 and 2 had worse disease-free survival (DFS) and disease-specific survival (DSS) than Group 3 (P < 0.01), while no significant difference was found between these two groups. HPV-negative status was a risk factor for both DFS (P < 0.05) and DSS (P < 0.01) in univariate but not multivariate Cox regression.

CONCLUSIONS

Joint detection of multiple technologies and evaluation of clinicopathological characteristics discriminate between HPV-independent and low-copy HPV-associated CSCC cases that present similar prognoses. Additional attention should be paid to these low-copy HPV-associated cases in clinical practice.

Reproducibility of Morphologic Parameters of the International Endocervical Adenocarcinoma Criteria and Classification System and Correlation With Clinicopathologic Parameters: A Multi-Institutional Study

Endocervical adenocarcinomas (ECAs) have been recently reclassified according to their morphologic features linked to etiology by the International Endocervical Adenocarcinoma Criteria and Classification (IECC) and this system is adopted by WHO 2020. This classification separates the ECAs as human papillomavirus (HPV)-associated (HPVA) and HPV-independent (HPVI) subtypes. According to WHO 2020, high risk (HR)-HPV association can be histologically recognized by the presence of luminal mitoses and apoptosis. Therefore, investigating the reproducibility of the morphologic criteria of this new classification will be important in observing the recognizability of tumor types. Full slide sets of 94 ECAs were collected from 4 institutions in Turkey and reclassified on the basis of IECC/WHO 2020 criteria and the presence or absence of HR-HPV. HR-HPV presence was confirmed by HPV DNA in situ hybridization, p16 immunohistochemistry and in conflicted cases with real time-polymerase chain reaction. The final diagnoses were given based on the combination of the histologic evaluation and ancillary test results. Our cohort consisted of 73.4% HPVA and 26.6% HPVI cases. According to the WHO 2020 criteria 92.7% of HPVAs and 88% of HPVIs were easily classified. HPV DNA in situ hybridization was positive in 91.3% of the HPVAs and p16 was positive in all HPVAs, and also positive in 8% of the HPVIs. In conclusion, most of the ECAs can be diagnosed by their characteristic morphologic features by the WHO 2020 criteria. However, we want to emphasize that mitosis/apoptosis criteria may not be helpful especially in mucinous ECAs and ancillary tests for HR-HPV should be used in challenging cases.

Clinical correlation of lymphovascular invasion and Silva pattern of invasion in early-stage endocervical adenocarcinoma: proposed binary Silva classification system

Silva invasion pattern can help predict lymph node metastasis risk in endocervical adenocarcinoma. We analysed Silva pattern of invasion and lymphovascular invasion to determine associations with clinical outcomes in stage IA and IB1 endocervical adenocarcinomas. International Federation of Gynecology and Obstetrics (FIGO; 2019 classification) stage IA-IB1 endocervical adenocarcinomas from 15 international institutions were examined for Silva pattern, presence of lymphovascular invasion, and other prognostic parameters. Lymph node metastasis status, local/distant recurrences, and survival data were compared using appropriate statistical tests. Of 399 tumours, 152 (38.1%) were stage IA [IA1, 77 (19.3%); IA2, 75 (18.8%)] and 247 (61.9%) were stage IB1. On multivariate analysis, lymphovascular invasion (p=0.008) and Silva pattern (p<0.001) were significant factors when comparing stage IA versus IB1 endocervical adenocarcinomas. Overall survival was significantly associated with lymph node metastasis (p=0.028); recurrence-free survival was significantly associated with lymphovascular invasion (p=0.002) and stage (1B1 versus 1A) (p=0.002). Five and 10 year overall survival and recurrence-free survival rates were similar among Silva pattern A cases and Silva pattern B cases without lymphovascular invasion (p=0.165 and p=0.171, respectively). Silva pattern and lymphovascular invasion are important prognostic factors in stage IA1-IB1 endocervical adenocarcinomas and can supplement 2019 International Federation of Gynecology and Obstetrics staging. Our binary Silva classification system groups patients into low risk (patterns A and B without lymphovascular invasion) and high risk (pattern B with lymphovascular invasion and pattern C) categories.

Local and Metastatic Relapses in a Young Woman with Papillary Squamous Cell Carcinoma of the Uterine Cervix

Papillary squamous cell carcinoma (PSCC) is a rare histological type of cervical carcinoma whose biological behavior has not been fully established. A 33-year-old woman with an exophytic cervical mass underwent radical hysterectomy and bilateral pelvic lymph node dissection. Histological examination of the tumor revealed numerous papillary fronds lined by atypical stratified squamous cells, resembling high-grade squamous intraepithelial lesions or urothelium. She was diagnosed with stage IB1 PSCC. Three months postoperatively, a 5.7 cm vaginal stump mass was detected. She received chemoradiotherapy, which helped her achieve a complete response. However, nine months postoperatively, she developed pelvic lymph node metastases. We present a rare case of recurrent cervical PSCC in a young woman. PSCC of the uterine cervix can recur rapidly within just a few months and become aggressive, as in the present case.

Testing Algorithms for the Diagnosis of Malignant Glandular Tumors of the Uterine Cervix Histotyped per the International Endocervical Adenocarcinoma Criteria and Classification (IECC) System

The International Endocervical adenocarcinoma Criteria and Classification (IECC) categorizes tumors into human papilloma virus (HPV) associated (HPVA), not associated (NHPV), and invasive adenocarcinoma not otherwise specified (IA NOS). HPVA and NHPV encompass 11 histotypes and an algorithm of mucin content, HPV ribonucleic acid (RNA), estrogen receptor and GATA3 is proposed for the diagnosis of most. In this study, the IECC algorithm's diagnoses were compared with hematoxylin and eosin (H&E) based IECC histotyping. Kappa statistics measured performance agreement. With additional markers, hierarchical clustering by random forest (RF) classification identified the most discriminating between tumor types, and investigated other algorithms. Three pathologists independently reviewed digitized H&E images of n=152 primary cervical adenocarcinomas for IECC histotype and mucin content, and tissue microarrays for expression of HPV RNA by in situ hybridization and 16 antibodies by immunohistochemistry. Results were finalized by consensus. There were n=113 HPVA, n=22 NHPV, and n=17 IA NOS. Mucin was obvious in n=36 and limited in n=116. Among n=124 with satisfactory test results, HPV RNA was positive in n=96, estrogen receptor in n=72, and GATA3 in n=15. The IECC algorithm diagnosed n=99 which agreed with H&E histotyping in n=64 for a fair κ of 0.36 (95% confidence interval, 0.21-0.50): n=12 were undiagnosed and n=13 were IA NOS. Small sample sizes restricted RF to HPVA versus NHPV which were discriminated by p16, HPV RNA, and MUC6 with an area under the curve of 0.74 (95% confidence interval, 0.58-0.90). The IECC algorithm for histotyping under-performed. The RF algorithmin for categorization was favorable, but validation in larger studies and investigation of additional algorithms to discriminate between all IECC histotypes are needed.

International Endocervical Adenocarcinoma Criteria and Classification (IECC): An Independent Cohort With Clinical and Molecular Findings

Recently, the International Endocervical Adenocarcinoma Criteria and Classification (IECC) has reorganized the classification of endocervical adenocarcinomas (ECAs), separating them into human papilloma virus (HPV)-associated (HPVA) and HPVA independent (HPVI) categories. In this study, we sought to revalidate the IECC clinical findings in an independent cohort and assess the mutational differences between HPVA and HPVI ECAs using next generation sequencing. Consecutive cases of ECAs were reclassified under the IECC. Clinicopathologic information was collected and tissue was sent for targeted next-generation sequencing in 33 genes. Associations between HPV status, clinicopathologic parameters and mutation status, with survival were evaluated. The series comprised of 85/100 HPVA (63 HPVA-usual type, 4 villoglandular, 3 mucinous intestinal, 15 mucinous not otherwise specified) and 15/100 HPVI (9 gastric, 4 mesonephric, 1 clear cell, 1 not otherwise specified). HPVA ECAs presented at a lower age (P=0.001), smaller tumor sizes (P=0.011), less margin positivity (P=0.027), less Silva pattern C (P=0.002), and lower FIGO stages (P=0.020). HPVA had superior survival compared with HPVI ECA [overall survival (P=0.0026), disease-specific survival (P=0.0092), and progression-free survival (P=0.0041)]. Factors that correlated with worse prognosis irrespective of HPV status were FIGO stage, positive margins and lymphovascular invasion (P<0.05). TP53 mutations were detected in a significantly higher proportion of HPVIs than HPVAs (P<<0.001). The study revalidates the IECC system by reaffirming the clinical and prognostic differences between HPVA and HPVI ECAs in an independent dataset.

HPV-Negative Cervical Cancer: A Narrative Review

Cervical cancer (CC) is the fourth most frequent cancer in women worldwide. HPV infection is associated with the majority of CC cases, but a small proportion of CCs actually test negative for HPV. The prevalence of HPV among CC histotypes is very different. It has been suggested that HPV-negative CC may represent a biologically distinct subset of tumors, relying on a distinct pathogenetic pathway and carrying a poorer prognosis, than HPV-positive CCs. Although, the discordance in terms of sensitivity and specificity between different HPV tests as well as the potential errors in sampling and storing tissues may be considered as causes of false-negative results. The identification of HPV-negative CCs is essential for their correct management. The aim of this narrative review is to summarize the clinical and pathological features of this variant. We also discuss the pitfalls of different HPV tests possibly leading to classification errors.