Molecular characterization of gastric-type endocervical adenocarcinoma using next-generation sequencing

Gastric-type adenocarcinoma of the uterine cervix: clinical features and future directions

The concept of gastric-type mucinous carcinoma of the uterine cervix (GAS) has been accepted worldwide because of its aggressive clinical behaviour and the absence of high-risk human papilloma virus infection. The World Health Organization (WHO) 2020 classification divides cervical tumours into two categories: human papilloma virus-associated and human papilloma virus-independent. Hence, GAS is now classified as an human papilloma virus-independent gastric type. Because clinical studies have reported that GAS is refractory to conventional treatments such as chemotherapy and radiotherapy, especially at an advanced stage, and has aggressive features with widespread dissemination to unusual sites, such as the omentum, peritoneum and distant organs, it is urgent to establish new treatment strategies by comparing the molecular profiles of human papilloma virus-associated adenocarcinomas. A series of genetic mutations characteristic to GAS encourage the development of future treatment strategies such as targeted therapy and immunotherapy.

Gastric Type Endocervical Adenocarcinoma With Concurrent High-Grade Squamous Intraepithelial Lesion: A Clinicopathologic Study of Three Patients

OBJECTIVE

We investigate gastric-type endocervical adenocarcinoma (ECA), a prominent HPV-independent adenocarcinoma, and its coexistence with high-grade squamous intraepithelial lesion (HSIL) through the examination of three such tumors.

METHODS

In this study, we conducted an in-depth review of three patients with gastric-type ECA, each associated with high-risk HPV infection as detected on Pap smears. We detailed the clinical and pathological features of each patient and utilized RNAscope for high-risk HPV testing to ascertain HPV status in both gastric-type ECA and HSIL components. Immunohistochemistry with p16, p53, and other biomarkers was also applied.

RESULTS

The gastric-type ECA component, characterized by well-differentiated glands with abundant, clear to eosinophilic cytoplasm, distinct cellular borders, and pale nuclei with conspicuous nucleoli, tested negative for both p16 and high-risk HPV, unlike the concurrent HSIL components which were positive. Additionally, two tumors showed aberrant p53 protein expression in the gastric-type ECA areas, and elevated carbohydrate antigen19-9 levels were noted in two patients. Treatment consisted of total abdominal hysterectomy and bilateral salpingo-oophorectomy, supplemented by chemotherapy and/or radiation, with disease-free intervals of 24, 12, and 40 months post-treatment, respectively.

CONCLUSION

This study highlights the critical need for meticulous diagnostic protocols that combine morphological examination, immunohistochemistry, and HPV RNA in situ hybridization. The rarity of gastric-type ECA coexisting with HPV infection underscores the necessity for continuous research and vigilant monitoring in the field of gynecological oncology.

Comprehensive Molecular Profiling and Clinicopathological Characteristics of Gastric-Type Mucinous Carcinoma of the Uterine Cervix in Japanese Women

Gastric-type mucinous carcinoma (GAS) of the uterine cervix is the most common adenocarcinoma that develops independently of human papillomavirus infection; it is typically diagnosed at an advanced stage and has a poorer prognosis than usual-type endocervical adenocarcinoma. Few studies have examined the molecular profile of GAS, but genetic alterations in TP53 and STK11 have been repeatedly reported. We analyzed the clinicopathological characteristics and molecular profile of GAS. Fresh-frozen tissue specimens and formalin-fixed paraffin-embedded (FFPE) tissues from 13 patients with GAS treated between January 2000 and December 2020 were analyzed. We performed next-generation sequencing on eight fresh-frozen GAS specimens using the Cancer Hotspot Panel v2 (cases 1-8) and the FoundationOne companion diagnostic (F1CDx) assay on six FFPE samples (cases 8-13). Seventy-four genomic alterations were identified in 42 genes. In order of frequency, TP53, ATRX, CDKN2A, KRAS, APC, and STK11 were altered in at least three cases. Targetable genomic alterations were identified in all six patients' specimens analyzed using the F1CDx assay. GAS harbors various genomic alterations associated with sustained activation of signaling pathways or cell cycle regulation in addition to abnormalities in TP53, and precision medicine based on molecular profiling will be necessary to overcome GAS.

Therapeutic target biomarkers of patient-derived xenograft models of gastric-type cervical adenocarcinoma

Background

Most cervical adenocarcinomas are associated with human papillomavirus (HPV). Gastric-type cervical adenocarcinoma (GAS), an HPV-independent adenocarcinoma, shows an aggressive clinical feature, resulting in a poor prognosis. Resistance to chemotherapy poses a difficulty in managing patients with metastatic GAS. We aimed to establish patient-derived xenografts (PDXs) of tumors from two patients with GAS and evaluated protein biomarkers for drug development using immunohistochemistry.

Methods

Two PDXs were established 78 and 48 days after transplanting the patient's tumor tissues into immunodeficient mice, respectively. PDX and patient's tumor samples were stained for HER2, HER3, PMS2, MSH6, PanTrk, and ARID1A to evaluate biomarkers for therapeutic targets. In addition, whole exome sequencing and RNA sequencing were performed on available samples.

Results

The pathological findings in morphological features and immunohistochemical profiles from the established PDXs were similar to those from the patients' surgical tumor specimens. HER3 was overexpressed in the patient's tumors, and the corresponding PDX tumors and HER2 was weakly stained in both types of tumor samples. In all PDX and patient tumor samples, PMS2, MSH6, and ARID1A were retained, and PanTrk was not expressed. In addition, a total of 10 samples, including tumor tissue samples from 8 other GAS patients, were evaluated for HER3 expression scores, all of which were 2 + or higher.

Conclusions

In summary, we evaluated biomarkers for therapeutic targets using newly established PDX models of GAS. Frequent HER3 overexpression and HER2 expression in GAS tumors suggest the possibility of new treatments for patients with GAS by targeting HER3 and HER2.

Readthrough Approach Using NV Translational Readthrough-Inducing Drugs (TRIDs): A Study of the Possible Off-Target Effects on Natural Termination Codons (NTCs) on TP53 and Housekeeping Gene Expression

Nonsense mutations cause several genetic diseases such as cystic fibrosis, Duchenne muscular dystrophy, β-thalassemia, and Shwachman-Diamond syndrome. These mutations induce the formation of a premature termination codon (PTC) inside the mRNA sequence, resulting in the synthesis of truncated polypeptides. Nonsense suppression therapy mediated by translational readthrough-inducing drugs (TRIDs) is a promising approach to correct these genetic defects. TRIDs generate a ribosome miscoding of the PTC named "translational readthrough" and restore the synthesis of full-length and potentially functional proteins. The new oxadiazole-core TRIDs NV848, NV914, and NV930 (NV) showed translational readthrough activity in nonsense-related in vitro systems. In this work, the possible off-target effect of NV molecules on natural termination codons (NTCs) was investigated. Two different in vitro approaches were used to assess if the NV molecule treatment induces NTC readthrough: (1) a study of the translational-induced p53 molecular weight and functionality; (2) the evaluation of two housekeeping proteins' (Cys-C and β2M) molecular weights. Our results showed that the treatment with NV848, NV914, or NV930 did not induce any translation alterations in both experimental systems. The data suggested that NV molecules have a specific action for the PTCs and an undetectable effect on the NTCs.

Cervical Gastric-type Adenosquamous Carcinoma: Case Report of a Rare Neoplasm Associated With a BRCA1 Pathogenic Variant

Gastric-type adenocarcinoma is the commonest human papillomavirus (HPV)-independent adenocarcinoma of the cervix. We report a rare case of a primary cervical gastric-type adenocarcinoma with malignant squamous elements (gastric-type adenosquamous carcinoma) in a 64-yr-old female. This is only the third report of a cervical gastric-type adenosquamous carcinoma. The tumor was p16 negative and molecular studies for HPV were negative. Next-generation sequencing showed pathogenic variants in BRCA1 and KRAS , as well as variants of unknown significance in CDK12 and ATM and homozygous deletion of CDKN2A/CDKN2B . Pathologists should be aware that not all cervical adenosquamous carcinomas are HPV-associated and the term gastric-type adenosquamous carcinoma is recommended when malignant squamous elements are present within a gastric-type adenocarcinoma. In reporting this case, we discuss the differential and the possible therapeutic options raised by the presence of pathogenic variants in BRCA1 .

Lobular Endocervical Glandular Hyperplasia, a mimicker and potential pitfall for HPV-independent well differentiated Gastric-type Endocervical Adenocarcinoma: Case report and literature review focusing on histology, immunophenotype, and molecular findings

Lobular glandular endocervical hyperplasia is an uncommon benign entity within the spectrum of gastric-type endocervical lesions. We report a case of a 48-year-old woman who presented with a palpable mass and watery vaginal discharge. Ultrasound revealed an 8 cm × 4 cm × 3 cm multicystic mass affecting the cervix, and hysterectomy was performed. The well-delimited multicystic, mucinous mass distorted the entire cervix. Microscopically, endocervical glandular proliferation with a lobular architecture was observed. The glands were lined with a single layer of tall, mucin-rich, columnar cells with basal and bland nuclei. The lesion was positive for MUC6 marker and hormonal receptors were negative, while P53 expression was normal. Three years later, the patient remained disease free. Here, we discuss the differential diagnosis between lobular glandular endocervical hyperplasia and similar conditions, particularly gastric-type endocervical adenocarcinoma, and review the literature focusing on the molecular pathways underlying gastric-type endocervical lesions. This case highlights the importance of accurate diagnosis to ensure favorable outcomes.

Assessment of HER2 in Gastric-Type Endocervical Adenocarcinoma and its Prognostic Significance

As the most common type of human papillomavirus-independent endocervical adenocarcinomas (ECAs), gastric-type endocervical adenocarcinomas (GEAs) account for approximately 10% of all ECAs. Although anti-HER2 therapy has been proven effective in many cancers, it has not been used in ECAs, including GEAs, which is at least partly due to the lack of a well-defined guideline. Limited available data regarding HER2 in GEAs and ECAs have considerable variations likely caused by variations in the tumor type selection, testing methods, and scoring criteria. Here, we selected 58 GEA cases to examine the HER2 status using immunohistochemistry and fluorescent in situ hybridization and investigate the prognostic value and their association with other known or potential prognostic factors. When strong complete or lateral/basolateral membranous reactivity in ≥10% tumor cells was used to define HER2 positivity, relatively high prevalence of HER2 overexpression (10/58[17.2%]) and amplification (9/58 [15.5%]), as well as high immunohistochemistry-fluorescent in situ hybridization concordance rate (9/10 [90%]) was found in GEAs. A lateral/basolateral staining pattern ("U-shaped") was observed, at least focally, in most of HER2-positive (3+) and equivocal (2+) tumors. Notably, considerable heterogeneity of HER2 expression was observed in HER2 positive and equivocal cases (80.0% and 83.3%, respectively). HER2 overexpression and amplification were associated with worse progression-free survival (P = .047 and P = .032, respectively). Programmed death-ligand 1 expression was associated with worse progression-free survival (P = .032), whereas mutant-type p53 demonstrated no prognostic significance. Our work laid a solid foundation for the eventual development of a future standard HER2 testing guideline for GEAs.

Current status and molecular biology of human papillomavirus-independent gastric-type adenocarcinoma of the cervix

This article reviews the findings of clinical studies on gastric-type adenocarcinoma of the cervix to date, outline the molecular biological features identified in recent studies, and discusses the future therapeutic strategies. Gastric-type adenocarcinoma of the cervix is a new classification in the World Health Organization 2014 classification. The World Health Organization 2020 classification further divides cervical tumors into two categories: human papillomavirus-associated and human papillomavirus-independent. Thus, gastric-type adenocarcinoma of the cervix is now classified as a human papillomavirus-independent gastric type. Clinical studies have reported that gastric adenocarcinoma of the cervix is refractory to conventional chemotherapy and radiotherapy, and it is desirable to elucidate its molecular biological mechanism. A series of gene mutations characteristic to the gastric-type adenocarcinoma of the cervix encourage the development of future treatment strategies.

Case Report: A rare case of gastric-type adenocarcinoma of stumps of duplicated cervices in a 49-year-old woman: A case with hidden focus confused us a lot

Gastric-type endocervical adenocarcinoma (G-EAC) is a rare special type of cervical mucinous adenocarcinomas, and it is reported the incidence is unrelated to human papilloma virus infection. We report a rare case of G-EAC in stumps of duplicated cervices in a 49-year-old female patient. The woman complained of post-coital bleeding. She had a didelphic uterus with a duplex cervix, and had undergone subtotal hysterectomy 16 years ago. Gynecological examination revealed a normal-appearing right cervix, but the non-dominant side of the left cervix, which was buried and covered by the side wall of the left vagina, was difficult to view. After exposing, the left side cervix presented a mature appearance which was smaller than a normal cervix. Her serum carbohydrate antigen-19-9 levels was 112.59 U/ml. The right cervix's cytology was normal, whereas the left cervix had unusual glandular epithelial cells. HPV testing on both cervical smears was negative. Adenocarcinoma was identified at 3, 6, 12 o'clock at the right cervix in a colposcopy-directed punch biopsy, while no abnormality was found in the biopsy of the left cervix, nor in the curettage of the double cervices. Pelvic magnetic resonance imaging (MRI) revealed two cervical canals, with a 1.9cm×1.6cm mass inside the left cervix, and the left wall of the right cervix may be involved by the tumor of the left cervix. After much deliberation, we considered that the patient had adenocarcinoma of the left cervix stage IB1. Then, the patient underwent radical cervical resection with bilateral salpingo-oophorectomy and bilateral pelvic lymphadenectomy. Her final histopathology indicated G-EAC of the duplicated cervices. After surgery, she received concurrent chemoradiation. Currently, 29 months after the final chemotherapy was administered, the patient remains healthy. Because G-EAC with duplicated cervices is an uncommon cunning tumor with a bad prognosis, early identification and therapy are recommended to enhance the prognosis. The comprehensive evaluation of symptoms and gynecological examination with cervical cytology, colposcopy-directed punch biopsy, endocervical curettage and MRI examine together may assist in determining an accurate preoperative diagnosis.

A Rare Case of Endocervical Adenocarcinoma of Gastric Type

Gastric adenocarcinoma of the cervix (GAC) represents a rare mucinous endocervical cancer unrelated to human papillomavirus (HPV). GAC has been found to comprise approximately 10% of cervical adenocarcinomas internationally. As more cases have been identified, GAC has been further classified into subtypes such as poorly differentiated versus well-differentiated (also referred to as mucinous or adenoma malignum). This cancer coined the term "gastric" subtype due to its similarity to the pancreaticobiliary and gastric tissue lining. With limited data and similar histological and genetic features of GAC, this malignancy poses a challenge for clinicians when differentiating between metastasis from the gastrointestinal tract and GAC. Here, we present a case of a 55-year-old female who presented with postmenopausal bleeding and was found to have stage IA1 endocervical adenocarcinoma of gastric subtype. The purpose of this article is to introduce a rare type of gastric adenocarcinoma with a unique site of origin in order to better understand this disease process and potentially help clinicians better diagnose and treat patients with this malignancy in the future.

HPV-Negative Adenocarcinomas of the Uterine Cervix: From Molecular Characterization to Clinical Implications

Cervical cancer is the fourth most common cancer in women. It is the leading cause of female deaths in developing countries. Most of these cervical neoplasms are represented by squamous lesions. Cervical adenocarcinoma causes about a quarter of cervical cancers. In contrast to squamous lesions, cervical glandular disease is HPV-negative in about 15-20% of cases. HPV-negative cervical adenocarcinomas typically present in advanced stages at clinical evaluation, resulting in a poorer prognosis. The overall and disease-free survival of glandular lesions is lower than that of squamous lesions. Treatment options require definitive treatments, as fertility-sparing is not recommended. Moreover, the impact of HPV vaccination and primary HPV screening is likely to affect these lesions less; hence, the interest in this challenging topic for clinical practice. An updated review focusing on clinical and molecular characterization, prognostic factors, and therapeutic options may be helpful for properly managing such cervical lesions.

Small Cell and Other Rare Histologic Types of Cervical Cancer

PURPOSE OF REVIEW

The goal of this paper was to summarize the recent evidence on rare subtypes of cervical cancer including small-cell carcinoma of the cervix (SCCC), gastric-type adenocarcinoma, and carcinosarcoma.

RECENT FINDINGS

All three cervical cancer subtypes are aggressive with poor treatment response and high recurrence rates. Molecular studies have identified various actionable mutations in both SCCC (PIK3CA, MYC, TP53, PTEN, ARID1A, KRAS, BRCA2) and gastric-type adenocarcinoma (KRAS, ARID1A, PTEN). While there are a limited number of case reports demonstrating a favorable response for recurrent SCCC to immune checkpoint inhibitors, a larger case series failed to show benefit. The checkpoint inhibitors role in gastric-type adenocarcinoma and carcinosarcoma is yet to be determined. Ninety-one percent of SCCC cases show PARP expression, suggesting a possible role for PARP inhibitors; however, this has yet to be examined in future clinical trials. More studies are needed, with a focus on targeted therapies. The role of PARP inhibitors in SCCC is potentially promising, but significant collaboration between centers/groups will be required to achieve this.

Gastric-type mucinous endocervical adenocarcinomas: A case report and literature review

Gastric-type mucinous endocervical adenocarcinomas (GAS) are new variant types of cervical adenocarcinomas according to the 2014 World Health Organization (WHO) classification. GAS is a unique disease that can be differentiated from typical adenocarcinomas—it is less common and more aggressive and likely to have deep invasion and horizontal diffusion, invasion of the uterus and vagina, early distant metastases, and a lower 5-year survival rate compared to the usual-type cervical cancer. At present, initial treatment and postoperative adjuvant therapy are not conclusive, but early detection and early treatment are a consensus that can improve prognosis. Most of its occurrence has nothing to do with human papillomavirus (HPV) infection. Whether it is only negative for the subtypes that can be detected at present and whether it may be an unknown subtype of infection need to be further explored in the future. The clinical symptoms commonly include aqueous secretion, lower abdominal pain, and elevated serum carbohydrate antigen-19-9 (CA19-9) levels, which may be helpful for diagnosis. MRI and PET-CT can help to describe the characteristics of lesions and judge the state of the systemic metastasis. We believe that early detection and surgical treatment will give patients more benefits. Looking for potential gene and molecular changes and establishing biomarkers to identify molecular targets will be the key to early identification and target therapy.

[A tumor of the uterus with a falsely benign aspect]

We report the case of a 79 year-old woman, who was admitted in the department of digestive surgery for an occlusive syndrome. The abdominopelvic computed tomography revealed a voluminous mass infiltrating the uterus, the bladder and the colon. A monobloc surgery is performed. The histopathological examination evidences an invasion of these organs by a well-differentiated glandular proliferation composed of epithelial cells without atypia stained with keratin 7 and carcinoembryonar antigen, without expression of p16, hormonal receptors and keratin 20. Ki-67 labeling index was low. The diagnosis of minimal deviation gastric mucinous adenocarcinoma was proposed. This is an uncommon neoplasm comprising approximately 1% of all endocervical adenocarcinomas. This is a difficult histopathological which should be known by pathologist. It is correlated to a poor clinical outcome with a high tendency to lymph node and extra-uterine metastases, as illustrated in our observation.

Molecular Pathology of Human Papilloma Virus-Negative Cervical Cancers

Cervical cancer is the fourth most common cancer in women worldwide and is predominantly caused by infection with human papillomavirus (HPV). However, a small subset of cervical cancers tests negative for HPV, including true HPV-independent cancers and false-negative cases. True HPV-negative cancers appear to be more prevalent in certain pathological adenocarcinoma subtypes, such as gastric- and clear-cell-type adenocarcinomas. Moreover, HPV-negative cervical cancers have proven to be a biologically distinct tumor subset that follows a different pathogenetic pathway to HPV-associated cervical cancers. HPV-negative cervical cancers are often diagnosed at an advanced stage with a poor prognosis and are expected to persist in the post-HPV vaccination era; therefore, it is important to understand HPV-negative cancers. In this review, we provide a concise overview of the molecular pathology of HPV-negative cervical cancers, with a focus on their definitions, the potential causes of false-negative HPV tests, and the histology, genetic profiles, and pathogenesis of HPV-negative cancers.

Immunohistochemistry in gynecologic carcinomas: Practical update with diagnostic and clinical considerations based on the 2020 WHO classification of tumors

This review provides an update on immunohistochemistry applications-diagnostic, prognostic, and predictive-in the pathology evaluation of gynecologic carcinomas. The 5th edition of the WHO Classification of Female Genital Tumors introduced important changes in the diagnostic classification of lower genital tract, endometrial, and ovarian carcinomas, with major influence on the routine pathology practice. Lower genital tract carcinomas and their precursor lesions are now classified based on their human papillomavirus (HPV)-associated and HPV-independent pathogenesis, reflecting the clinically significant prognostic differences and impacting the therapeutic decision-making. Immunohistochemical markers have an increasing role in the pathology evaluation of endometrial carcinomas: in addition to their traditional use in the differential diagnosis and histologic subtyping, they have also been recently advocated for prognostic classification as surrogates for the TCGA (The Cancer Genome Atlas) molecular groups. New entities - mesonephric-like adenocarcinoma and gastric (gastrointestinal)-type mucinous adenocarcinoma of the endometrium - have also been added and often require immunostains for diagnostic confirmation. Ovarian carcinomas frequently show overlapping morphologic patterns and heterogeneous appearance within the same tumor, necessitating immunohistochemical work-up. Beyond diagnostic applications, there is increasing clinical demand for screening of inherited cancer syndromes, prediction of prognosis and guiding targeted therapy. Practical issues and pitfalls related to mismatch repair protein immunohistochemistry, HER2, and PD-L1 testing are also discussed.

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.

Immunohistochemical Loss of DPC4 in Tumors With Mucinous Differentiation Arising in or Involving the Gynecologic Tract

DPC4 immunohistochemistry (IHC) is usually part of the work-up of mucinous neoplasms in the ovary where the distinction between an ovarian primary and metastatic pancreaticobiliary adenocarcinoma (PanACa) must be made. Although DPC4 IHC is lost in about 55% (46%-61%) of PanACas and typically retained in most primary ovarian mucinous neoplasms, no study has evaluated the expression of this marker in a large cohort of neoplasms arising in or involving gynecologic (GYN) organs. In this study, we retrospectively analyzed the expression of DPC4 IHC in a total of 251 tumors and lesions related to the GYN tract in which DPC4 IHC stain was performed during the initial pathology evaluation. Of these, 138 were primary GYN tumors and lesions, 31 were metastatic GYN tumors involving non-GYN sites, and 83 were metastatic non-GYN tumors involving the GYN tract. We identified 27 cases with loss of DPC4 IHC expression of which 20 cases met the inclusion criteria (i.e. clinical information was available to determine the site of tumor origin). We observed that loss of DPC4 nuclear expression was most commonly seen in tumors of endocervical origin (n=7), of which 5 were gastric-type cervical adenocarcinomas (GCxACa) and 2 were usual-type cervical adenocarcinomas, either primary or metastatic. This was followed by tumors of the pancreaticobiliary tract (n=5), ovary (n=2), and appendix (n=1). In addition, 1 gastric-type vaginal adenocarcinoma (GVaACa) also showed loss of DPC4. Our findings indicate that in female patients with mucinous neoplasms involving the ovary or other sites, with loss of DPC4 by IHC, and negative pancreaticobiliary imaging, the possibility of an occult GCx/GVaACa, and rarely an ovarian primary must be considered.

Gene of the month: STK11

STK11 encodes for the protein liver kinase B1, a serine/threonine kinase which is involved in a number of physiological processes including regulation of cellular metabolism, cell polarity and the DNA damage response. It acts as a tumour suppressor via multiple mechanisms, most classically through AMP-activated protein kinase-mediated inhibition of the mammalian target of rapamycin signalling pathway. Germline loss-of-function mutations in STK11 give rise to Peutz-Jeghers syndrome, which is associated with hamartomatous polyps of the gastrointestinal tract, mucocutaneous pigmentation and a substantially increased lifetime risk of many cancers. In the sporadic setting, STK11 mutations are commonly seen in a subset of adenocarcinomas of the lung in addition to a number of other tumours occurring at various sites. Mutations in STK11 have been associated with worse prognoses across a range of malignancies and may be a predictor of poor response to immunotherapy in a subset of lung cancers, though further studies are needed before the presence of STK11 mutations can be implemented as a routine clinical biomarker.

Immunohistochemical and genetic characteristics of HPV-associated endocervical carcinoma with an invasive stratified mucin-producing carcinoma (ISMC) component

Invasive stratified mucin-producing carcinoma (ISMC) is a recently described entity of human papillomavirus (HPV)-associated endocervical adenocarcinoma with phenotypic plasticity and aggressive clinical behavior. To identify the cell of origin of ISMC, we investigated the immunohistochemical expression of cervical epithelial cell markers (CK7, PAX8, CK5/6, p63, and CK17), stemness markers (ALDH1 and Nanog), and epithelial-mesenchymal transition (EMT) markers (Snail, Twist, and E-cadherin) in 10 pure and mixed type ISMCs with at least 10% of ISMC component in the entire tumor, seven usual type endocervical adenocarcinomas (UEAs), and seven squamous cell carcinomas (SCCs). In addition, targeted sequencing was performed in 10 ISMCs. ISMC was significantly associated with larger tumor size (p = 0.011), more frequent lymphovascular invasion and lymph node metastasis (p < 0.001), higher FIGO stage (p = 0.022), and a tendency for worse clinical outcomes (p = 0.056) compared to other HPV-associated subtypes. ISMC showed negative or borderline positivity for PAX8, CK5/6, and p63, which were distinct from UEA and SCC (p < 0.01). Compared to UEA and SCC, ISMC showed higher expression for ALDH1 (p = 0.119 for UEA and p = 0.009 for SCC), Snail (p = 0.036), and Twist (p = 0.119), and tended to show decreased E-cadherin expression (p = 0.083). In next-generation sequencing analysis, ISMC exhibited frequent STK11, MET, FANCA, and PALB2 mutations compared to conventional cervical carcinomas, and genes related to EMT and stemness were frequently altered. EMT-prone and stemness characteristics and peripheral expression of reserve cell and EMT markers of ISMC suggest its cervical reserve cell origin. We recommend PAX8, CK5/6, and p63 as diagnostic triple biomarkers for ISMC. These findings highlight the distinct biological basis of ISMC.

Clinicopathological Characteristics of Gastric-type Endocervical Adenocarcinoma Misdiagnosed as an Endometrial, Ovarian or Extragenital Malignancy, or Mistyped as Usual-type Endocervical Adenocarcinoma

BACKGROUND/AIM

The diagnosis of gastric-type endocervical adenocarcinoma (GEA) is challenging because its differential diagnosis includes not only gynecological tumors, but also extragenital tumors.

PATIENTS AND METHODS

We reviewed the electronic medical records and all available slides to investigate the clinicopathological characteristics of eight misdiagnosed GEA cases.

RESULTS

Three tumors were initially misdiagnosed as endometrial carcinoma. They displayed extensive endomyometrial involvement and complex glandular architecture, but no severe nuclear pleomorphism. Another three tumors were misclassified as usual-type endocervical adenocarcinoma because of mucin-poor, pseudoendometrioid glands, apical mitotic figures, and karyorrhectic debris. The two remaining tumors presenting as adnexal masses mimicked primary ovarian mucinous tumor and metastatic cholangiocarcinoma.

CONCLUSION

The varying pathological characteristics of GEA reflect the variability in clinical manifestations and its diagnostic difficulties. It is challenging to make an accurate diagnosis based solely on histological features. When suspecting GEA, clinicians should consider more comprehensively the clinicopathological context, along with immunostaining results.

Massively parallel sequencing analysis of 68 gastric-type cervical adenocarcinomas reveals mutations in cell cycle-related genes and potentially targetable mutations

Gastric-type cervical adenocarcinoma (GCA) is an aggressive type of endocervical adenocarcinoma characterized by mucinous morphology, gastric-type mucin, lack of association with human papillomavirus (HPV) and resistance to chemo/radiotherapy. We characterized the landscape of genetic alterations in a large cohort of GCAs, and compared it with that of usual-type HPV-associated endocervical adenocarcinomas (UEAs), pancreatic adenocarcinomas (PAs) and intestinal-type gastric adenocarcinomas (IGAs). GCAs (n = 68) were subjected to massively parallel sequencing targeting 410-468 cancer-related genes. Somatic mutations and copy number alterations (CNAs) were determined using validated bioinformatics methods. Mutational data for UEAs (n = 21), PAs (n = 178), and IGAs (n = 148) from The Cancer Genome Atlas (TCGA) were obtained from cBioPortal. GCAs most frequently harbored somatic mutations in TP53 (41%), CDKN2A (18%), KRAS (18%), and STK11 (10%). Potentially targetable mutations were identified in ERBB3 (10%), ERBB2 (8%), and BRAF (4%). GCAs displayed low levels of CNAs with no recurrent amplifications or homozygous deletions. In contrast to UEAs, GCAs harbored more frequent mutations affecting cell cycle-related genes including TP53 (41% vs 5%, p < 0.01) and CDKN2A (18% vs 0%, p = 0.01), and fewer PIK3CA mutations (7% vs 33%, p = 0.01). TP53 mutations were less prevalent in GCAs compared to PAs (41% vs 56%, p < 0.05) and IGAs (41% vs 57%, p < 0.05). GCAs showed a higher frequency of STK11 mutations than PAs (10% vs 2%, p < 0.05) and IGAs (10% vs 1%, p < 0.05). GCAs harbored more frequent mutations in ERBB2 and ERBB3 (9% vs 1%, and 10% vs 0.5%, both p < 0.01) compared to PAs, and in CDKN2A (18% vs 1%, p < 0.05) and KRAS (18% vs 6%, p < 0.05) compared to IGAs. GCAs harbor recurrent somatic mutations in cell cycle-related genes and in potentially targetable genes, including ERBB2/3. Mutations in genes such as STK11 may be used as supportive evidence to help distinguish GCAs from other adenocarcinomas with similar morphology in metastatic sites.

Genomic Characterization of HPV-related and Gastric-type Endocervical Adenocarcinoma: Correlation With Subtype and Clinical Behavior

The majority of endocervical adenocarcinomas (EAs) are caused by human papillomavirus (HPV). Gastric-type EA, the second most common EA and unrelated to HPV, is biologically different with a more aggressive clinical course. Our knowledge of the molecular fingerprint of these important EA types and its role in diagnosis, prognosis and management is still evolving. Thus, we sought to evaluate the genomic profile of HPV-related and gastric EA. Clinical information including patient outcome was gathered for 56 tumors (45 HPV-associated and 11 gastric-type) surveying evaluated by a targeted massively parallel sequencing assay (OncoPanel platform) which surveys exonic DNA sequences of 447 cancer genes and 191 regions across 60 genes for rearrangement detection. KRAS, TP53, and PIK3CA were the most commonly mutated genes (10, 10, and 9 cases, respectively). Alterations in TP53, STK11, CDKN2A, ATM, and NTRK3 were significantly more common in gastric-type EA (P<0.05, Fisher exact test). Disease recurrence and/or death occurred in 14/49 (29%) cases with clinical information available 7 HPV-related (18% of HPV-related cases with clinical information available) and 7 gastric-type (64% of gastric-type cases with clinical information available). Tumors associated with adverse outcome, regardless of histotype, more commonly had alterations in KRAS (2 HPV-related, 4 gastric-type), GNAS (3 HPV-related, 1 gastric-type), and CDKN2A (0 HPV-related, 3 gastric type) compared with indolent-behaving cases (P<0.05, Fisher exact test). A total of 8/56 (14%) tumors harbored at least one actionable mutation; of these, 6 (75%) were associated with recurrence and/or cancer-related death. Copy number variations were detected in 45/56 cases (80%). The most frequent were chromosome 20 gain and 16q loss, identified in 7 cases each (all HPV-associated EA). The mutational profile of EA is diverse and correlates with clinical behavior and EA subtype. Thus, targeted sequencing assays can potentially serve as a diagnostic and prognostic tool. It can also identify targetable alterations, which may benefit patients with recurrent/metastatic disease.

Ovarian mucinous and seromucinous neoplasms: problematic aspects and modern diagnostic approach

The morphological spectrum of primary ovarian mucinous and seromucinous tumours is broad and presents an array of diagnostic challenges, many unique to these tumour types. This reflects the heterogeneous nature of these lesions, their varied histogenesis and evolving classification systems over recent decades, with further modification to the seromucinous category incorporated in the recently published 5^th edition of the WHO Classification of Female Genital Tumours. In this review we provide an update on the classification of these neoplasms and discuss their histogenesis and diverse morphology, focusing on areas which are diagnostically problematic. We also cover tumour grading, differential diagnosis, immunohistochemistry, the recent elucidation of the molecular underpinnings of ovarian mucinous neoplasia and discuss the gross and intraoperative handling of these tumours. A number of diagnostic issues remain unresolved highlighting the importance of further research on this front, as well as a multidisciplinary approach in the care of patients with ovarian mucinous and seromucinous neoplasia.

Clinicopathological and Molecular Differences Between Gastric-type Mucinous Carcinoma and Usual-type Endocervical Adenocarcinoma of the Uterine Cervix

BACKGROUND/AIM

We investigated differences in the clinicopathological and molecular characteristics between gastric-type mucinous carcinoma (GMC) and usual-type endocervical adenocarcinoma (UEA).

PATIENTS AND METHODS

We collected the clinicopathological information and performed targeted genomic sequencing analysis.

RESULTS

GMCs exhibited significantly deeper invasion depth, larger horizontal spread, more advanced stage, more frequent distant metastasis, and more frequent parametrial and vaginal extension. Disease-free survival time of GMC patients was significantly shorter than that of UEA patients. GMCs displayed mutant p53 immunostaining pattern, whereas UEAs exhibited p16 block positivity. GMCs harbored mutations in KRAS, TP53, NF1, CDKN2A, STK11, and ARID1A. One GMC exhibited MDM2 amplification. In contrast, UEAs harbored mutations in HRAS, PIK3CA, and BRCA2. Two UEAs were found to have novel TP53 mutations.

CONCLUSION

GMC is associated with more aggressive behavior than UEA. Distinctive p53 and p16 immunostaining patterns enable differential diagnosis. GMC and UEA exhibit genetic heterogeneity with potentially actionable molecular alterations.

Comprehensive genomic profiling and prognostic analysis of cervical gastric-type mucinous adenocarcinoma

Gastric-type mucinous adenocarcinoma (GAS) is an uncommon cervical adenocarcinoma, which is not associated with human papillomavirus (HPV) infection. Compared with HPV-associated cervical adenocarcinoma, GAS has characteristics of larger volume, deep invasion, and easy to metastasize to distant sites. Also, GAS is typically resistant to chemo/radiotherapy. Few studies have reported the molecular genetic characteristics of GAS. In order to investigate the molecular genetic characteristics of GAS and reveal its possible pathogenesis, 15 GAS patients were enrolled from Peking University People's Hospital (2009-2019) and examined with next-generation sequencing (NGS). Based on the clinicopathologic feature analysis, we found that the presence of lymph node metastasis and extensive lymphovascular invasion were associated with poor survival outcomes of GAS (p = 0.0042 and p = 0.005, respectively). Based on the NGS testing, our results showed that the most frequently mutated gene was TP53 (8/15, 53.3%), followed by STK11, CDKN2A, and ARID1A. STK11 mutations were more frequent in well-differentiated GAS (33.3% vs. 0.0%, p = 0.026) and patients with extensive lymphovascular invasion (33.3% vs. 0.0%, p = 0.044). Survival analysis revealed that STK11 mutations were significantly associated with the poor prognosis of GAS (p = 0.01). Our results also showed that mutations in the target drug were detected in 53.3% of GAS patients. Patients with ERBB2 amplification (13.3%) presented the highest level of evidence according to OncoKB recommendations. These results indicate that the genomic alterations of GAS mainly involved the cell cycle and PI3K/AKT signaling pathways, and some therapeutic candidates were identified in GAS patients.

Tumor Typing of Endocervical Adenocarcinoma: Contemporary Review and Recommendations From the International Society of Gynecological Pathologists

The incidence of endocervical adenocarcinoma, the second most common cervical cancer in the world, has been on the rise. While most cervical cancers are squamous cell carcinomas and associated with high-risk oncogenic human papillomavirus (HPV), approximately 15% of endocervical adenocarcinomas, which now represent about one quarter of all cervical cancers, are HPV-independent. In this review, we will focus on the shortcomings of historical histologic classification systems of female genital tract tumors as they pertain to endocervical adenocarcinomas, and we will highlight the advantages of the new International Endocervical Adenocarcinoma Criteria and Classification system, which forms the basis for the WHO 2020 classification. We will cover the various histologic types, subtypes, and variants of endocervical adenocarcinoma with regard to morphology, immunophenotype, molecular genetics, HPV status and differential diagnosis, and we will provide International Society of Gynecological Pathologists recommendations for diagnosing these tumors.

Genetic characteristics of gastric-type mucinous carcinoma of the uterine cervix

Gastric-type mucinous carcinoma (GAS) is a recently established variant of endocervical mucinous adenocarcinoma that is characterized as being unrelated to HPV and having aggressive behavior and chemoresistance. GAS has a distinct morphology resembling nonneoplastic gastric glands or pancreaticobiliary adenocarcinoma, and their possible genetic similarity has been posed. In this study, next-generation sequencing was performed in 21 GAS cases using a customized panel including 94 cancer-associated genes. A total of 54 nonsynonymous somatic mutations were detected with an average mutation rate of 2.6 per lesion (range: 0-9). The most frequently mutated gene was TP53 (11/21, 52.4%), followed by STK11, HLA-B, PTPRS (4/21, 19.0%), FGFR4 (3/21, 14.3%), GNAS, BRCA2, ELF3, ERBB3, KMT2D, SLX4 (2/21, 9.5%), CDH1, EPCAM, KRAS, MLH1, RNF43, SNAI1, TWIST1, ZEB1, ZEB2, and so on (1/21, 4.8%). The mutated genes were mostly involved in signal transduction, DNA damage repair, and epithelial-mesenchymal transition (EMT). Correlation of TP53 mutation and p53 protein expression demonstrated that 31.3% with abnormal p53 expression harbored wild-type TP53. Compared to genetic features of gastric and pancreaticobiliary adenocarcinoma, TP53 mutations were frequent in both GAS and gastrointestinal adenocarcinoma. While KMT2D, ERBB3, and RNF43 mutations were shared between GAS and gastric adenocarcinoma, highly mutated genes in pancreatic ductal adenocarcinoma such as KRAS, SMAD4, and CDKN2A were rarely mutated in GAS. Of frequently mutated genes in cholangiocarcinoma, BAP1 and HLA-B were identified in GAS. Frequent EMT-related gene mutations suggested a possible role of EMT-related pathways in tumor dissemination and chemoresistance of GAS. In addition, GAS shared some genetic features with gastrointestinal adenocarcinoma. These findings provide a clue in understanding the biological basis of GAS.

The Role of Predictive Biomarkers in Endocervical Adenocarcinoma: Recommendations From the International Society of Gynecological Pathologists

To review the scientific evidence related to predictive biomarkers in cervical adenocarcinoma (ADC). The authors reviewed the literature regarding predictive biomarkers in cervical ADC. There were several limitations: (1) there is an overlap between predictive and prognostic biomarkers, as the vast majority of patients are treated with anticancer strategies; (2) in many studies and clinical trials, cervical ADC patients are included in a large series of patients predominantly composed of cervical squamous cell carcinomas; and (3) in most of the studies, and clinical trials, there is no distinction between human papillomavirus (HPV)-associated and HPV-independent cervical ADCs, or between various histologic subtypes. Results obtained from a small group of studies confirm that cervical ADCs exhibit distinct molecular features as compared with squamous carcinomas, and that there are different molecular features between different types of cervical ADCs. Promising areas of interest include ERBB2 (HER2) mutations and PD-L1 expression as predictive biomarkers for anti-HER2 treatment and immunotherapy, respectively. To date, no definitive data can be obtained from the literature regarding predictive biomarkers for cervical ADC. Clinical trials specifically designed for endocervical ADC patients are required to elucidate the predictive value of HER2 mutations and PD-L1 expression. The distinction between HPV-associated and HPV-independent cervical ADCs as well as early involvement of pathologists in the design of future clinical trials are needed to identify new predictive biomarkers in cervical ADC.

Gastric-type cervical adenocarcinoma with squamous differentiation: buried in adenosquamous carcinomas?

Gastric-type adenocarcinoma (GAS) of the cervix is a human papilloma virus (HPV)-independent, aggressive, and chemo-resistant adenocarcinoma. However, although the histopathological features of GAS have been extensively investigated, squamous differentiation has not been mentioned. This study aimed to elucidate the frequency of GAS with squamous differentiation and describe their clinicopathological characteristics. We retrospectively evaluated 78 patients with GAS (n = 13) and adenosquamous carcinoma (n = 65) diagnosed between 2000 and 2020. Two patients with GAS with squamous differentiation were identified. Both tumors showed advanced stage (pT2bN1) and had predominant GAS and merged squamous cell carcinoma components without p16-block positivity and HPV DNA. Gastric-type adenocarcinoma in situ was confirmed in both cases. Some cases of GAS could show squamous differentiation mimicking the usual, HPV-associated, adenosquamous carcinoma. GAS with squamous differentiation is recognized as an HPV-independent cancer.

Cervical carcinomas with serous-like papillary and micropapillary components: illustrating the heterogeneity of primary cervical carcinomas

Recent changes in the classification of cervical adenocarcinomas have re-categorized serous carcinoma as potentially nonexistent. However, clinical and pathological profiles of cervical adenocarcinomas with serous-like morphological features have not been systematically evaluated using the latest taxonomy and biomarkers. We studied 14 cases of primary cervical carcinomas with serous-like morphologies (papillary and micropapillary patterns). None of these cases exhibited evidence of serous carcinoma involving the upper tracts. Patient ages ranged between 34 and 86 years, most presented with abnormal uterine bleeding. Histologically, ten cases were classified as human papillomavirus (HPV)-associated carcinomas (eight usual-type endocervical adenocarcinomas and two adenosquamous carcinomas), of which six exhibited a papillary pattern and four had a micropapillary pattern. The four remaining cases were HPV-independent gastric-type adenocarcinomas, which displayed a papillary pattern in one case and a micropapillary pattern in three others. All ten HPV-associated carcinomas displayed block positive p16 and wild-type p53 by immunohistochemistry, with nine of them confirmed by HPV testing. Two of the four gastric-type adenocarcinomas had mutation-type p53, one of which also being p16 block positive. HER2 overexpression was demonstrated in 3/14 (21.4%) cases (2 HPV-associated and 1 HPV-independent). PD-L1 expression was identified in 4/10 (40%) cases, all HPV-associated. Targeted next-generation sequencing was performed in two cases with a micropapillary pattern, revealing a missense variant in ATM in an HPV-associated tumor and missense variants in TP53 and SMARCB1 in an HPV-independent tumor. The results demonstrated that primary endocervical adenocarcinomas can mimic the appearance of serous carcinoma, while not representing serous carcinoma. Serous-like papillary and micropapillary patterns may be present in both HPV-associated and HPV-independent cervical carcinomas, but none of the cases studied were unequivocally serous upon detailed analysis. Our findings support the exclusion of "cervical serous carcinoma" from existing classifications of cervical adenocarcinoma.

Cytomorphologic Features of Gastric-Type Endocervical Adenocarcinoma in Liquid-Based Preparations

OBJECTIVE

Gastric-type endocervical adenocarcinoma (GAS) is a recently described, uncommon, and aggressive tumor with distinct morphologic features and HPV-independent etiology. Data on GAS in liquid-based cytology (LBC) Papanicolaou (Pap) test preparations from a North American patient population are scant. We systematically assessed the cytomorphologic characteristics of GAS in LBC from patients in Ontario and examined if glandular cell nuclear area could represent a readily assessable feature which may aid in GAS detection.

STUDY DESIGN

Pap test slides preceding the diagnosis of GAS were retrieved locally or requested from outside laboratories. A structured review of 15 cytomorphologic features was performed using the available LBC Pap test slides of GAS and a set of usual-type endocervical adenocarcinomas (UEA). Morphometry of the glandular cell nuclear area was performed, and normalized values were compared to UEA and benign endocervical cells.

RESULTS

At least 1 Pap test (5 ThinPrep®, 11 SurePath®, and 1 direct smear) was available for 14 patients. Original LBC Pap test diagnoses were negative for intraepithelial lesion or malignancy (NILM) (7), adenocarcinoma/carcinoma (6), atypical glandular cells (2), and adenocarcinoma in situ (1). Review detected abnormal glandular cells in 6/7 NILM cases. Honeycomb-like sheets, nuclear enlargement, and microvesicular cytoplasm were the single most common architectural, nuclear, and cytoplasmic features, respectively. Microvesicular cytoplasm (100 vs. 17%), honeycomb-like sheets (87 vs. 8%), prominent nucleoli (93 vs. 25%), and anisonucleosis (93 vs. 50%) were most discriminatory for GAS versus UEA, respectively. Yellow mucin, intranuclear cytoplasmic pseudoinclusions, and goblet/Paneth-like cells were uncommon, but unique for GAS. Glandular cell nuclear area normalized to neutrophils was found to be significantly increased in GAS compared to benign endocervical cells.

CONCLUSIONS

GAS is under-recognized and may mimic reactive endocervical cells. Awareness of the tumor type and its cytomorphology is critical for early detection. Identification of glandular cells with uniform nuclear enlargement in conjunction with any of the other cytologic features may help avoid false-negative Pap results. Neutrophils may serve as convenient size reference and visual aid.

An analysis of HER2 amplification in cervical adenocarcinoma: correlation with clinical outcomes and the International Endocervical Adenocarcinoma Criteria and Classification

Few studies have explored HER2 status in cervical adenocarcinoma, particularly in the gastric-type adenocarcinoma (GAC), a nonhuman-papillomavirus-related subtype with poor clinical outcomes. In this study, we investigated HER2 expression and amplification by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) in 209 well annotated cervical adenocarcinomas diagnosed using the International Endocervical Adenocarcinoma Criteria and Classification. IHC identified HER2 protein expression in 57.4% (123/209) of adenocarcinomas, of which 62 were IHC 1+ (negative), 38 2+ (equivocal) and 23 3+ (positive). HER2 amplification was found in 13 cases (6.2%) including 10 with IHC 3+ and 3 with IHC 2+. Among all the major histotypes of cervical adenocarcinoma, HER2 amplification was most common in GAC cases with a frequency of 14.7% (5/34). Moreover, HER2 amplification was more frequently associated with 2018 International Federation of Gynecology & Obstetrics (FIGO) stage III/IV, perineural involvement and ovarian spread (p < 0.05) while IHC 3+ was more common in patients with lymphovascular invasion and ovarian involvement (p < 0.05). Survival analysis indicated that FIGO stage III/IV, GAC, and p53 overexpression were associated with poor disease-specific survival and tumor recurrence (p < 0.05). In conclusion, HER2 amplification was present in a subset of adenocarcinomas, and more common in GAC, pointing to a potential benefit from trastuzumab treatment. HER2 overexpression does not identify gene amplification status in cervical adenocarcinoma; therefore, FISH is suggested for both IHC positive and equivocal cases. Further investigation on more cases with longer follow-up times is required to consolidate these findings.

Gastric-type endocervical adenocarcinoma and cervical cytology: Experience at a general hospital and review of the literature

INTRODUCTION

Gastric-type endocervical adenocarcinoma (GAS) is an uncommon type of endocervical adenocarcinoma that is not associated with human papillomavirus infection. This diagnosis is relatively rare and may portend a worse prognosis than usual-type endocervical adenocarcinoma. Subtle morphological features make it an under-recognised diagnostic challenge. Study of the cytological features of individual cases is valuable in order to increase awareness of this entity.

METHODS

The pathology database of our institution was searched for the diagnosis of GAS and all cytological and surgical specimens for each patient were reviewed. The original cytological interpretation was compared to a retrospective central review interpretation. Clinical history and follow-up results were obtained from the electronic medical record.

RESULTS

Four cases of GAS were identified. The findings on initial cervical cytology varied, with GAS found in both patients with negative cervical cytology and those with atypical glandular cells. Cytological findings included endocervical cells arranged in three-dimensional clusters and honeycomb sheets with abundant vacuolar cytoplasm, and in two patients, moderate nuclear atypia with irregular nuclear membranes, coarse chromatin, hyperchromatic nuclei, and prominent nucleoli. In one patient, GAS was incidentally discovered via thorough sampling of a cystic lesion in the superior portion of the endocervical canal.

CONCLUSIONS

GAS is an aggressive human papillomavirus-independent type of endocervical adenocarcinoma with subtle morphological features and, as our study shows, varying clinical presentation. Given the aggressive nature of GAS and the difficulties in initial diagnosis, increased awareness of this entity among pathologists is crucial.

The new world of poly-(ADP)-ribose polymerase inhibitors (PARPi) used in the treatment of gynecological cancers

The clinical development of poly-(ADP)-ribose polymerase inhibitors (PARPi) began with the treatment of ovarian cancer patients harboring BRCA1/2 mutations and continues to be expanded to other gynecological cancers. Furthermore, The Cancer Genome Atlas (TCGA) analysis of endometrial and cervical cancers offered rationale that PARPi may be an option for treatment based on the molecular profiles of these cancer types. This review summarizes the current indications of PARPi, such as its role in the treatment and maintenance of recurrent ovarian cancer and for first-line maintenance therapy in advanced ovarian cancer. We also outline new concepts for PARPi therapy in other gynecological cancers such as endometrial and cervical cancers based on recent clinical data. Finally, we present potential future directions to continue exploring the world of PARPi resistance and combining PARPi with other therapies.

The Evolving Spectrum of Precursor Lesions of Cervical Adenocarcinomas

Modern classification schemes divide cervical adenocarcinomas into human papillomavirus (HPV)-associated and HPV-independent types. The precursor lesions of the former are well known and comprise HPV-associated (usual/endocervical) adenocarcinoma in situ (AIS) and the much less common stratified mucin-producing intraepithelial lesion (SMILE). The precursor lesions of HPV-independent cervical adenocarcinomas are much less well known, although postulated precursors of gastric-type adenocarcinoma include atypical lobular endocervical glandular hyperplasia and gastric-type AIS. In this review, we cover HPV-associated and HPV-independent precursor lesions of cervical adenocarcinomas concentrating on diagnostic criteria (morphology and immunophenotype) and differential diagnosis. We propose a uniform terminology and diagnostic criteria for precursor lesions showing intestinal differentiation with goblet cells because this may be a feature of both HPV-associated and HPV-independent AIS.

Cervical adenocarcinoma: integration of HPV status, pattern of invasion, morphology and molecular markers into classification

Cervical adenocarcinoma is a heterogenous group of tumours with various aetiologies, molecular drivers, morphologies, response to treatment and prognosis. It has become evident that human papillomavirus (HPV) infection does not drive all adenocarcinomas, and appropriate classification is critical for patient management, especially in the era of the HPV vaccine and HPV-only screening. Identified as one of the most important developments in gynaecological pathology during the past 50 years, the separation of cervical adenocarcinomas into HPV-associated (HPVA) and HPV-independent has resulted in a transformation of the classification system for cervical adenocarcinomas. HPVA has been traditionally subclassified by morphology, such as usual type (UEA), mucinous and villoglandular, etc. However, it has become evident that cell type-based histomorphological classification is not clinically meaningful, and the newly proposed International Endocervical Adenocarcinoma Criteria and Classification (IECC) is a necessary and relevant break from this prior system. Non-HPV-associated adenocarcinomas can be divided by their distinct morphology and molecular genomics with very different responses to standard therapies and potential for future targeted therapies. These include gastric-type, clear-cell, mesonephric and endometrioid adenocarcinomas. So-called 'serous' carcinomas of the cervix probably represent morphological variants of UEA or drop metastases from uterine or adnexal serous carcinomas, and the existence of true cervical serous carcinomas is in question. This review will discuss the advances since WHO 2014, and how HPV status, pattern of invasion as described by Silva and colleagues, histological features and molecular markers can be used to refine diagnosis and prognostication for patients with cervical adenocarcinoma.

Transcriptome profiling of gastric-type endocervical adenocarcinomas identifies key signaling pathways for tumor progression

OBJECTIVE

Gastric-type endocervical carcinoma is a rare entity of carcinoma of the cervix. In contrast to the intestinal type, the gastric type is not related to Human Papilloma Virus (HPV) infection and has been reported to be much more aggressive than the usual type. Oncogenic pathways involved in this poor-prognosis phenotype are largely unexplored.

METHODS

We compared activation of the main signaling pathways involved in cancer progression between the intestinal- (n = 5), gastric- (n = 6) and usual-type (n = 6) adenocarcinomas of the cervix using a targeted transcriptomic approach (expression of 770 genes) on FFPE samples.

RESULTS

We identified a gene-expression signature composed of 11 genes that allows the classification of these endocervical carcinoma as three distinct molecular entities. There were similarities between mucinous endocervical carcinomas (gastric and intestinal types) despite difference in pathogenesis related to HPV infection. Among HPV-related endocervical carcinoma, the intestinal type could be molecularly distinguished from the usual type by high expression of EIF2AK3 and low expression of PPFIBP2 genes, supporting its classification as a distinct entity. Overexpression of TAL1 and S1PR1 genes were characteristic of the gastric type. The usual type was characterized by high expression of occludin and VAV3 genes. Tight junction disruptions might play an essential role in the metastatic potential of mucinous endocervical carcinoma with concomitant loss of OCLN and claudin 4 proteins. An overexpression of NTRK1 transcript was observed in mucinous endocervical carcinomas when compared to the usual type.

CONCLUSIONS

This transcriptomic study identified a signature that supports the classification of endocervical carcinomas as three distinct entities: usual-, intestinal- and gastric-type. It also points out to disruption of tight junctions as a potential mechanism of metastatic dissemination of these rare tumors.