Gastric-type Endocervical Adenocarcinoma Research Articles

Gastric-type Endocervical Adenocarcinoma Associated with Peutz-Jeghers Syndrome: A Case Report with Imaging Findings

Gastric-type Endocervical Adenocarcinoma Associated with Peutz-Jeghers Syndrome: A Case Report with Imaging Findings

Comparison of Clinicopathological and Prognostic Characteristics Between Minimal Deviation Adenocarcinoma and Gastric-type Endocervical Adenocarcinoma.

Minimal deviation adenocarcinoma (MDA) is an extremely well-differentiated variant of gastric-type endocervical adenocarcinoma (GEA). This study compared the clinicopathological and prognostic characteristics of MDA to those of GEA. Nine MDAs and 22 GEAs were included in this study. We reviewed electronic medical records and pathology slides to collect clinicopathological and prognostic information. GEA showed significantly higher stage at presentation, more frequent parametrial extension and lymphovascular space invasion, and recurrence than MDA. Patients with GEA had significantly lower survival rates than those with MDA. None of the cases with MDA exhibited singly dispersed or clustered tumor cells, diffuse stromal desmoplasia, severe nuclear pleomorphism, loss of nuclear polarity, or coarse chromatin, all of which were frequently observed in GEA. Significant differences were observed in the clinicopathological characteristics and patient outcomes between MDA and GEA. Further investigations using a larger cohort are warranted to determine the clinical behavior and aggressiveness of MDA.

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

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. 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. 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. 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.

Preoperative multimodal ultrasonic imaging in a case of Peutz-Jeghers syndrome complicated by atypical lobular endocervical glandular hyperplasia: a case report and literature review

BackgroundPeutz-Jeghers syndrome (PJS), an autosomal dominant multiple cancerous disorder, is clinically characterized by mucocutaneous macules and multiple gastrointestinal hamartomatous polyps. Gastric-type endocervical adenocarcinoma (G-EAC), a special subtype of cervical adenocarcinoma with non-specific symptoms and signs, is known to occur in approximately 11% of female patients with PJS.Case presentationHere, we report a case of PJS in a 24-year-old female with multiple mucocutaneous black macules who complained of vaginal discharge and menorrhagia. Moreover, we first described the multimodal ultrasonographical manifestations of PJS-correlated G-EAC. The three-dimensional reconstructed view of G-EAC on 3D realisticVue exhibited a distinctive “cosmos pattern” resembling features on magnetic resonance imaging, and the contrast-enhanced ultrasound displayed a “quick-up and slow-down” pattern of the solid components inside the mixed cervical echoes. We reported the multimodal ultrasonographical characteristics of a case of PJS-related G-EAC, as well as reviewed PJS-related literature and medical imaging features and clinical characteristics of G-EAC to provide insight into the feasibility and potential of utilizing multimodal ultrasonography for the diagnosis of G-EAC.ConclusionsMultimodal ultrasound can visualize morphological features, solid components inside, and blood supplies of the G-EAC lesion and distinguish the G-EAC lesion from normal adjacent tissues. This facilitates preoperative diagnosis and staging of PJS-related G-EAC, thereby aiding subsequent health and reproductive management for patients with PJS.

Expression of B7-H3 and TIM-3 in gastric-type endocervical adenocarcinoma: prevalence, association with PD-L1 expression, and prognostic significance.

Gastric-type endocervical adenocarcinoma (GEA) is the second most common subtype of endocervical adenocarcinoma and has a poor prognosis. Anti-programmed death-1 and anti-programmed death-ligand 1 (PD-L1) inhibitors have emerged as a major treatment option for GEA; however, data on the expression of other immune checkpoints in GEA are limited. We analyzed the expression of T-cell immunoglobulin and mucin-domain containing-3 (TIM-3) and B7 homolog 3 protein (B7-H3) in 58 GEA and investigated their prognostic significance as well as association with PD-L1 expression and other known prognostic factors. Applying the tumor proportion score (TPS) with a cutoff of 1%, B7-H3 and TIM-3 were present in 48.3% and 17.2% of cases, respectively. Applying the combined positive score (CPS) with a cutoff of 1, TIM-3 expression was present in 70.7% of cases. Moreover, the expression of three checkpoints (B7-H3, TIM-3, and PD-L1) was incompletely overlapping. Patients with B7-H3 positive tumors (by TPS) or TIM-3 positive tumors (by TPS) had significantly worse recurrence-free survival (RFS) and overall survival (OS) (log-rank). Using CPS, patients with TIM-3 positive tumors showed significantly worse RFS (log-rank). Similarly, B7-H3 positivity (by TPS) and TIM-3 positivity (by TPS) were associated with worse RFS and OS in univariate analysis. TIM-3 positivity (by CPS) was associated with worse RFS in univariate analysis and the final Cox multivariate analysis. In conclusion, our results show that (1) B7-H3 and TIM-3 are frequently expressed in GEA and their expression overlaps incompletely with PD-L1; and (2) both B7-H3 and TIM-3 are independent negative prognostic markers in GEA.

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.

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 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

S2784 A Case of Delayed Cervical Cancer Diagnosis in a Patient With Crohn’s Disease

Introduction: Increased cancer risk in inflammatory bowel disease (IBD) is thought to be due to immunosuppression from biologic therapy and/or inflammation. Women with IBD have an increased risk of melanoma and adenocarcinoma of the small bowel and colon, and those that are on an immunosuppressive regimen that includes azathioprine have an additional increased risk of lymphoma and squamous cell carcinoma of the skin and cervix. Here we present a case of a patient with an atypical and rare malignancy, whose diagnosis was delayed due to overlap in the symptoms of the malignancy and her known IBD diagnosis. Case Description/Methods: A woman in her mid 40s with a 28-year history of colonic Crohn’s disease maintained on ustekinumab injection. She was previously taking azathioprine for 7 years and initially responded to adalimumab, but after a flare, was switched to ustekinumab with symptomatic and endoscopic response. She then presented to her gynecologist in November 2020 with complaints of bloating and large amounts of clear vaginal discharge. A cervical exam and routine pap smear of the ectocervix showed normal cytology. Eight months later, the patient presented to her gastroenterologist with worsening bloating, hematochezia, left lower quadrant pain, and persistent vaginal discharge. The patient was concerned for an IBD flare, but noted that the abdominal bloating and vaginal discharge were different than her usual flare. After CT abdomen/pelvis revealed 2 large pelvic complex cystic lesions, her biologic was stopped and she underwent a hysterectomy with bilateral salpingo-oophorectomy. Pathology revealed non-HPV associated invasive moderately differentiated gastric-type endocervical adenocarcinoma. She completed treatment with an anti-VEGF antibody, but a restaging PET scan six months later showed uptake consistent with peritoneal carcinomatosis. Discussion: This immunosuppressed patient had an advanced and aggressive non-HPV endocervical cancer which was missed on ectocervical pap smear. Pap smears that include inadequate endocervical samples are considered suboptimal, but are usually not grounds for further testing in the average patient. However, Crohn’s disease patients have increased risk of low- and high-grade squamous epithelial cervical lesions and cervical cancer compared to women without IBD, likely due to a combination of elevated inflammatory state and immunosuppressive medications. Cervical cancer screening in immunosuppressed patients with IBD should include adequate endocervical sampling.

Cytopathologic features of human papillomavirus–independent, gastric-type endocervical adenocarcinoma

BackgroundGastric-type endocervical adenocarcinoma (GEA) is unrelated to human papillomavirus (HPV) infection and is clinically aggressive compared with HPV-associated usual-type endocervical adenocarcinoma (UEA). The cytological diagnosis falls short of a definitive diagnosis of GEA and is often categorized as atypical glandular cells (AGCs). To improve cytologic recognition, cytological findings of HPV-independent GEA were analyzed and the results compared with HPV-associated UEA.MethodsCervical Papanicolaou (Pap) smears from eight patients with a histopathologic diagnosis of GEA and 12 control cases of UEA were reviewed. All slides were conventionally prepared and/or liquid-based prepared (ThinPrep) and stained following the Pap method. A mucinous background, architectural, nuclear, and cytoplasmic features were analyzed and compared with UEA.ResultsPreoperative cytologic diagnoses of the eight GEA cases were AGCs, favor neoplastic in three cases, adenocarcinoma in situ in one case, and adenocarcinoma in four cases. Cytologically, monolayered honeycomb-like sheets (p = .002) of atypical endocervical cells with vacuolar granular cytoplasm (p = .001) were extensive in GEA, and three-dimensional clusters (p = .010) were extensive in UEA. Although the differences were not statistically significant, background mucin (p = .058), vesicular nuclei (p = .057), and golden-brown intracytoplasmic mucin (p = .089) were also discriminatory findings for GEA versus UEA.ConclusionsAlthough GEA is difficult to diagnose on cytologic screening, GEA can be recognized based on cytologic features of monolayered honeycomb sheets of atypical endocervical cells with abundant vacuolar cytoplasm and some golden-brown intracytoplasmic mucin. UEA cases are characterized by three-dimensional clusters.

Clinical Diagnosis and Treatment Analysis of 16 Cases of Gastric-Type Endocervical Adenocarcinoma

Objective: Cervical cancer classification based on human papillomavirus (HPV) infection status is necessary, as the popularity of HPV vaccination is increasing. Hence, this study aimed to explore the clinicopathological features, diagnosis, treatment, and prognosis of gastric-type endocervical adenocarcinoma (GAS) in west China. Methods: We performed a retrospective analysis and follow-up of patients with GAS who were hospitalized in West China Second University Hospital, a tertiary care center in west China, between September 2019 and April 2021. Results: A total of 16 cases were pathologically diagnosed as GAS at the hospital, most of which had no specific clinical manifestations. Among the 16 cases, 3 cases were confirmed preoperatively. The occurrence of full-layer cervix stroma infiltration, lymphatic vessel infiltration, and lymph node metastasis were 87.5%, 100%, and 50%, respectively. Among all cases, 8 cases were classified as stage III according to the International Federation of Gynecology and Obstetrics 2018 Clinical Staging Standard for cervical cancer. A total of 15 patients underwent a transabdominal or laparoscopic extensive hysterectomy, and the remaining 1 patient was pathologically diagnosed with GAS after a total hysterectomy and afterward underwent bilateral oophorectomy and pelvic lymph node dissection as supplementary surgeries. The follow-up data presented the survival of the 16 patients receiving concurrent chemoradiotherapy after surgery. However, GAS recurred in 3 non-medically-controlled patients among the 16 patients in 3 to 6 months after the treatment. Conclusions: GAS is a rare but highly malignant cancer that usually results in a poor prognosis. A few reports of GAS diagnosis and treatment, especially from developing countries, are available. Hitherto clinical routine screening methods might be insufficient to fulfill the requirements of GAS diagnosis owing to the difficulties in preoperative diagnosis and the probability of misdiagnosis. To reduce the rate of misdiagnosis, repeated deep multisite biopsies, cervical curettage, cervical conization, and hysteroscopy might be helpful in suspicious GAS cases.

Membranous and nuclear staining of CLDN18 in HPV-independent and HPV-associated endocervical adenocarcinomas.

A classification system for endocervical adenocarcinoma (ECA) based on high-risk human papillomavirus (HPV) status has been established; however, the immunohistochemical markers distinguishing HPV-independent and HPV-associated ECAs have not been fully described. Here, we aimed to characterize ECA immunopathological features. We evaluated the immunohistochemical profile of CLDN18, CDX2, PAX8, p16, p53, and CEA in 60 ECAs comprising 10 HPV-independent ECAs and 50 HPV-associated ECAs. Both the membranous and nuclear expression levels of CLDN18 were analyzed. Membranous CLDN18 (CLDN18 [M]) was found to be expressed in the mucinous epithelium of all HPV-independent ECAs, including eight gastric-type ECAs (G-ECAs), one endometrioid ECA, and one clear cell ECA, but no nuclear CLDN18 (CLDN18 [N]) expression was detected in HPV-independent ECAs. Among HPV-associated ECAs, CLDN18 (M) expression levels in intestinal-type (I-ECAs) and usual-type ECAs (U-ECAs) were significantly different from those in invasive stratified mucin-producing (iSMILE) carcinomas (p=0.036). Positive CLDN18 (M) staining was present in 55.6% (5/9) of intestinal-type and 39.4% (13/33) of usual-type ECAs and was not present in iSMILE ECAs. Silva pattern C cancers expressed higher levels of CLDN18 (M) than Silva pattern A and B cancers (p=0.004), whereas the CLDN18 (N) expression levels in cancers showing Silva pattern A were significantly higher than those in cancers exhibiting Silva patterns B and C (p < 0.001). Membranous CLDN18 is expressed in ECAs and is particularly frequently expressed in HPV-independent ECAs, and membranous CLDN18 expression has potential as a therapeutic target. Nuclear staining of CLDN18 is a new immunohistochemical marker for diagnosing Silva pattern A HPV-associated ECAs and is associated with a good prognosis. Further studies should investigate the therapeutic and prognostic significance of membranous and nuclear CLDN18 expression and develop a related test that can be implemented in the clinical evaluation of ECAs.

Independent validation of distinct clinicopathological features and prognosis among usual-type, mucinous-type and gastric-type endocervical adenocarcinoma categorised by new WHO classification (2020)

The new World Health Organization (WHO) classification of tumours of the female genital tract (2020) divides endocervical adenocarcinoma (EAC) into human papilloma virus (HPV)-related adenocarcinoma (HPVA) and HPV-independent adenocarcinoma (HPVI) to underscore the morphological and pathogenetic correlation. It may be potentially prognostic. In this study, we appraised the new WHO classification in an independent, single institution-based EAC cohort from China to assess the clinicopathological features and prognostic value among tumour types. Our study cohort contained 402 consecutive, surgically excised EACs consisting of 298 (74.1%) HPVA, 88 (21.9%) HPVI and 16 (4%) adenocarcinomas not otherwise specified (NOS). Usual-type (55.7%) and gastric-type adenocarcinoma (GAC) (18.2%) was the most common type in HPVA and HPVI, respectively. Block p16 staining (94.7% vs 24.4%) and HPV mRNA signal (89.4% vs 0) were more common in HPVA than in HPVI (p<0.001). HPVI or GAC were more frequently associated with prognostically adverse variables including old age, large tumour size, deep invasion of the cervical wall, high tumour stage, spread of the upper genital tract, lymphovascular invasion, and mutant-type p53 expression, compared to HPVA or mucinous/usual-type HPVA, respectively (all p<0.001). In univariate survival analysis, HPVI had a worse overall survival and higher tumour recurrence compared to HPVA (p<0.05). Mucinous-type HPVA showed a worse prognosis than usual-type HPVA, but better than GAC (p<0.001). Multivariate survival analysis demonstrated that HPVI was independently associated with a worse overall survival and tumour recurrence (p<0.05) while GAC was an adverse prognostic factor independently of FIGO stage (p<0.05). Our findings validate the value of the new WHO classification in prognostic stratification and pathogenetic correlation in EAC and its subtypes.

Clear Cell Carcinoma (CCC) of the Cervix Is a Human Papillomavirus (HPV)-independent Tumor Associated With Poor Outcome: A Comprehensive Analysis of 58 Cases.

Cervical clear cell carcinoma (CCC) is a rare human papillomavirus-independent adenocarcinoma. While recent studies have focused on gastric-type endocervical adenocarcinoma (GTA), little is known about CCC. A total of 58 (CCCs) were collected from 14 international institutions and retrospectively analyzed using univariable and multivariable methods and compared with 36 gastric-type adenocarcinomas and 173 human papillomavirus-associated (HPVA) endocervical adenocarcinoma (ECA) regarding overall survival (OS) and recurrence-free survival (RFS). Most cases were FIGO stage I (72.4%), with Silva C pattern of invasion (77.6%), and the majority were treated with radical surgery (84.5%) and adjuvant therapy (55.2%). Lymphovascular invasion was present in 31%, while lymph node metastasis was seen in 24.1%; 10.3% were associated with abdominopelvic metastases at the time of diagnosis; 32.8% had recurrences, and 19% died of disease. We did not find statistically significant differences in OS and RFS between CCC and GTA at 5 and 10 years (P=0.313 and 0.508, respectively), but there were significant differences in both OS and RFS between CCC and HPVA ECA (P=0.003 and 0.032, respectively). Also, OS and RFS in stage I clear cell and GTA were similar (P=0.632 and 0.692, respectively). Multivariate analysis showed that OS is influenced by the presence of recurrence (P=0.009), while RFS is influenced by the FIGO stage (P=0.025). Cervical CCC has poorer outcomes than HPVA ECA and similar outcomes to human papillomavirus-independent GTA. Oncologic treatment significantly influences RFS in univariate analysis but is not an independent prognostic factor in multivariate analysis suggesting that alternative therapies should be investigated.

Ovarian Metastasis by Gastric-type Endocervical Adenocarcinoma: A Clinicopathologic Description of 12 Cases.

Cervical gastric-type adenocarcinoma has a propensity for ovarian metastasis, but the clinicopathologic findings and possible routes of tumor spread have not been well characterized to date. To address these points, we reported 12 cervical gastric-type adenocarcinomas with ovarian metastases from a single institution. Seven patients with gastric-type adenocarcinoma had concurrent endometrial fallopian tube involvement, 5 of which showed tumors confined to the fallopian tube mucosa. Two of these 5 patients died of disease at 2 and 16 mo, and 1 recurred at 18 mo. In the remaining 5 patients, 3 had wide pelvic/peritoneal spread while the other 2 showed no evidence of uterine or tubal involvement. Among them, 1 died of disease at 94 mo, and another relapsed at 20 mo. Morphologically, ovarian tumors frequently had surface involvement consistent with metastasis, but also mimicked a primary tumor with a mixture of benign/borderline/intraepithelial carcinoma-like areas, as well as carcinoma with expansile or destructive stromal invasion. The tubal lesions were predominantly in the form of mucosal colonization without invasion of the underlying structures. Block p16 and high-risk human papillomavirus mRNA signals were not detected in cervical gastric-type adenocarcinomas and ovarian metastatic tumors. We conclude that fallopian tube spread may be associated with ovarian metastasis of cervical gastric-type adenocarcinomas that have bad clinical outcomes. Ovarian involvement may be a part of the aggressive nature of these tumors.

A retrospective study on incidence, diagnosis, and clinical outcome of gastric-type endocervical adenocarcinoma in a single institution

BackgroundGastric-type endocervical adenocarcinoma is rare but the most common subtype of cervical adenocarcinoma not associated with human papillomavirus. It is more aggressive with a shorter five-year survival rate compared to human papillomavirus-associated usual type endocervical adenocarcinoma. The objectives of our study were to determine the incidence and clinical-pathological characteristics of Gastric-type endocervical adenocarcinoma in a single institution.MethodsTwenty four cases of invasive cervical adenocarcinoma were identified between January 2000 and December 2015, from the Saskatoon Health Region pathology database using International Endocervical Adenocarcinoma Criteria and Classification to retrospectively classify endocervical adenocarcinoma. Immunohistochemistry was performed with antibodies for Gastric mucin-6 (MUC-6), p16INK4a, cyclin-dependent kinase inhibitor 2A (p16), p53 protein (p53), estrogen and progesterone receptors. Clinical and pathological data was retrieved from pathology reports and charts. Statistical analysis was performed using Mann-Whitney U test and Chi-Square test.ResultsUsing the International Endocervical Adenocarcinoma Criteria and Classification criteria, 19 cases (79.2%) were classified as human papillomavirus-associated usual type endocervical adenocarcinoma, and five cases (20.8%) as Gastric-type endocervical adenocarcinoma. In our study 40% of Gastric-type endocervical adenocarcinoma cases presented at stage III compared to none of the usual type endocervical carcinoma cases. All the Gastric-type endocervical adenocarcinoma cases were positive for MUC-6, and negative for p16. 60% Gastric-type endocervical adenocarcinoma cases demonstrated mutant type p53 staining. In contrast, 84.2% of human papillomavirus-associated usual type endocervical adenocarcinoma cases showed block like nuclear and cytoplasmic positivity with p16 antibodies. The Gastric-type endocervical adenocarcinoma group had significantly shorter median survival time than human papillomavirus-associated usual type endocervical adenocarcinoma group, Gastric-type endocervical adenocarcinoma is 22 months compared to human papillomavirus-associated usual type endocervical adenocarcinoma at 118 months (p = 0.043).ConclusionsIn this study, Gastric-type endocervical adenocarcinoma accounted for 20.8% of all cervical adenocarcinoma with higher stage at presentation and shorter overall survival. Criteria proposed by International Endocervical Adenocarcinoma Criteria and Classification (IECC) are simple and reproducible in differentiating between, HPV- associated (HPVA) and non HPV associated (NHPVA) endocervical adenocarcinoma. Although none of the IHC assays is specific for GAS, but p16, MUC-6, ER, PR and p53 may further aid in confirming GAS and to differentiate it from benign and malignant mimics.

Abstract 2930: Characterization based on therapeutic target biomarkers of patients-driven xenografts model of gastric-type cervical adenocarcinoma

Abstract The majority of cervical adenocarcinomas are associated with human papillomavirus (HPV) mainly HPV types 18 and 16. Patients with gastric-type endocervical adenocarcinoma (GAS) have an aggressive clinical behavior, resulting in poor prognosis compared to those with HPV-associated usual type adenocarcinoma. Chemotherapy resistance to taxane and carboplatin-based regimen has also been reported, which poses a difficulty in managing GAS patients with metastatic lesion. We established patient-driven xenografts (PDX) of two GAS patients and evaluated protein biomarkers for drug development using immunohistochemistry staining. The pathological findings of the established PDX were confirmed by HE staining and special staining to be similar to the pathological findings obtained from the patients' surgical specimens. PDX was established 78 and 48 days after transplantation of patient tumor tissue into immunodeficient mice, respectively. HER2, HER3, PMS2, MSH6, PanTrk, and ARID1A were stained for both PDX and patient-tumor samples to evaluate biomarkers for therapeutic targets. All staining results were consistent between patient tumor samples and PDX for both patients. Staining results for HER3 showed that both patients' tumors and the corresponding PDXs were 3+. Staining for HER2 was 1+ in both cases. In all PDX and patient-tumor samaples, PMS2, MSH6 and ARID1A showed no loss of protein expression, and PanTrk showed no protein expression. In addition, nine additional tumor tissue specimens from GAS patients diagnosed at our institution were stained for HER3 and HER2. HER3 was 3+ in 3 cases and 2+ in 6 cases, and HER2 was 3+ in 1 case, 2+ in 3 cases and 1+ in 5 cases. The present study showed overexpression of HER2 and HER3, suggesting a therapeutic potential of targeting HER2 and/or HER3 in GAS patients. We are next planning an in vivo study to develop therapies in GAS patients. Citation Format: Yuki Kojima, Hiroshi Yoshida, Toshihiro Okuya, Hitomi S. Okuma, Tadaaki Nishikawa, Maki Tanioka, Kazuki Sudo, Emi Noguchi, Tatsunori Shimoi, Yasuhito Tanase, Masaya Uno, Mitsuya Ishikawa, Yasuhiro Fujiwara, Kan Yonemori, Tomoyasu Kato. Characterization based on therapeutic target biomarkers of patients-driven xenografts model of gastric-type cervical adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2930.

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

The diagnosis of gastric-type endocervical adenocarcinoma (GEA) is challenging because its differential diagnosis includes not only gynecological tumors, but also extragenital tumors. We reviewed the electronic medical records and all available slides to investigate the clinicopathological characteristics of eight misdiagnosed GEA cases. 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. 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.

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.

Gastric-type endocervical adenocarcinoma: Review of clinicopathologic characteristics and recent advances

Gastric-type endocervical adenocarcinoma (ECAC) represents a unique variant of endocervical adenocarcinoma that is distinguished by lack of HPV association and an aggressive clinical course with unfavorable prognosis.

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

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. 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. 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. 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.