Magnetic resonance imaging findings and prognosis of gastric-type mucinous adenocarcinoma (minimal deviation adenocarcinoma or adenoma malignum) of the uterine corpus: Two case reports

Primary Endometrial Gastric (Gastrointestinal)-type Mucinous Adenocarcinoma: A Detailed Clinicopathologic and Molecular Analysis of 27 Cases

Endometrial gastric (gastrointestinal)-type mucinous adenocarcinoma (EmGA) is rare and was introduced as a new entity in the latest World Health Organization (WHO) classification of female genital tumors. Herein, we report a detailed clinicopathologic, immunohistochemical, and molecular study of 27 EmGA, the largest published series to date. The cohort consisted of 27 patients (median age 69 y; range 42 to 87 years). Histologically all cases showed gastric/gastrointestinal differentiation with foamy apical cytoplasm with distinct cell borders (n=21), goblet cells (n=9), signet ring cells (n=4), and Paneth cells (n=1). Using FIGO grading, 5 were grade 1, 14 grade 2, and 8 grade 3. Tumors were positive for MUC6 (10/21), CK7 (22/24), CK20 (16/24), CDX2 (24/26), and Claudin 18 (9/12). In all, 12/27 exhibited aberrant p53 expression and 3/26 showed MLH1 and PMS2 loss, including 2 with confirmed MLH1 gene promoter methylation. Next-generation sequencing showed pathogenic variants in TP53 (13/20), KRAS (7/20), PIK3CA (5/20), BRCA2 (4/20), SMAD4 (3/20), and POLE (1/20). Using TCGA classification (based on cases with available molecular results), 1/20 was POLE mutated, 2/20 were mismatch repair deficient (MMRd), 4/20 were no specific molecular profile (NSMP), and 13/20 were TP53 abnormal. FIGO stage (2009 staging system) ranged from IA to IVB. Outcome data (21 patients; follow-up of 2 to 77 mo) showed that 2 patients died of disease at 14 and 46 months after diagnosis, 1 patient died from other causes at 28 months, 8 were alive with disease, and 10 were alive with no evidence of disease. Like the cervical counterpart, primary EmGA has a distinctive morphologic appearance, harbors frequent TP53 mutations, and can be associated with adverse outcomes despite low-grade morphology and/or low-stage at presentation. They may be represented in all 4 TCGA molecular groups.

High-grade Endometrial Carcinoma With Serous and Colorectal Carcinoma-like Components: Unique Morphology in Correlation With Immunohistochemical and Molecular Findings

Endometrial carcinoma with intestinal differentiation/colorectal carcinoma-like (CRC-like) features is rare with few cases reported to date. Those described are mainly endometrioid carcinomas with intestinal differentiation. We report a case of high-grade endometrial carcinoma with serous and intestinal/CRC-like components. The gross, histologic, immunohistochemical, and molecular features are described for both components of the tumor in the initial diagnostic biopsy and subsequent resection specimen. The diagnosis of primary endometrial carcinoma with serous and CRC-like components is supported by immunohistochemical and molecular findings, as well as clinical workup. The rarity of this phenomenon poses diagnostic challenges. In addition, the literature is reviewed with specific emphasis on the molecular and pathologic features of mixed endometrial carcinomas, including those with intestinal/CRC-like features.

Gastric-type glandular lesions of the female genital tract excluding the cervix: emerging pathological entities

In the last two decades or so, a spectrum of benign, premalignant and malignant cervical glandular lesions exhibiting gastric differentiation has been described, with gastric-type adenocarcinoma representing the most common human papillomavirus (HPV)-independent cervical adenocarcinoma. More recently, limited literature has reported a variety of gastric-type glandular lesions at other sites within the female genital tract and, as in the cervix (the most common site for these lesions), a spectrum of benign, premalignant and malignant lesions has been proposed. We provide an update and review of the emerging spectrum of gastric-type glandular lesions at female genital tract sites other than the cervix. In the endometrium, putative gastric-type glandular lesions include mucinous metaplasia of gastric-type, atypical mucinous proliferation of gastric-type and gastric-type adenocarcinoma. Similarly in the vagina, gastric-type adenosis, atypical adenosis and adenocarcinoma have been described. There have also been occasional reports of gastric-type lesions involving the ovary and fallopian tube. We provide guidance on how to recognise gastric-type lesions morphologically and immunophenotypically and stress that sometimes these lesions occur at more than one site within the female genital tract (synchronous/multifocal gastric-type lesions of the female genital tract), sometimes in association with Peutz-Jeghers syndrome.

Intestinal‑type mucinous carcinoma of the endometrium showing a polypoidal exophytic form: A case report

Although endometrial cancer is a common malignancy in women, rare histological subtypes can pose diagnostic challenges. Primary endometrial intestinal-type mucinous carcinoma is a newly recognized subtype of endometrial cancer that differs from Müllerian-type endometrial mucinous carcinoma. The present case report documents a rare case of intestinal-type mucinous carcinoma of the endometrium showing a polypoidal exophytic form. The patient, an 80-year-old female, was incidentally diagnosed with a uterine tumor during a follow-up for vulvar Paget's disease. Clinical and imaging examinations revealed a localized mass within the uterine cavity. Hysteroscopy and subsequent histological examination confirmed the presence of intestinal-type mucinous carcinoma of the endometrium. Microscopically, the tumor displayed adenocarcinoma containing an intestinal-type glandular epithelium with mild nuclear atypia. It stained positive for the gastrointestinal markers mucin 2 and caudal type homeobox 2, and stained negatively for estrogen receptor α. The patient underwent surgery and adjuvant chemotherapy, with no evidence of recurrence at the latest follow-up 6 months after surgery. Endometrial intestinal-type mucinous carcinoma is a rare histological subtype of endometrial cancer. Differential diagnoses include Müllerian-type endometrial mucinous carcinoma, endocervical adenocarcinoma, metastasis from gastrointestinal tract adenocarcinoma and non-neoplastic gastric/intestinal metaplasia. However, the prognosis of endometrial intestinal-type mucinous carcinoma remains unclear due to limited reported cases. Existing evidence suggests a poorer prognosis compared with classical mucinous carcinomas of the endometrium. The present case, which is characterized by a polypoidal exophytic tumor without myometrial invasion, showed a favorable outcome. Further documentation and characterization of the aforementioned rare malignancy are necessary to enhance the understanding of its clinical physiology and outcomes. The present case report highlights the diagnostic challenges associated with intestinal-type mucinous endometrial carcinoma. The inclusion of this type of malignancy in the latest World Health Organization classification emphasizes the need for further comprehensive studies and case reports to expand the current knowledge on this rare histological subtype.

Gastric (gastrointestinal)-type endometrial adenocarcinoma presenting as a solitary endometrial polyp: a case report and literature review on a novel and potentially aggressive endometrial cancer histotype

Gastric-type carcinoma of the endometrium is a rare endometrial cancer histotype, recently introduced in the 2020 WHO classification of the female genital tract tumors. Clinico-pathological features, as well as treatment strategies for this rare histotype, are not fully defined. We herein present an unusual case of endometrial carcinoma with mucinous features arising in a 58-year-old menopausal woman. Morphological features of the present case as well as immunohistochemical profile were consistent with gastrointestinal differentiation. Therefore, after clinical and imaging studies ruled out the possibility of a metastatic origin, a final diagnosis of gastric-type carcinoma of the endometrium was rendered.

Primary endometrial gastric (gastro-intestinal)-type carcinoma: A practical approach

The latest WHO classification of the female genital tract tumors introduces a new type of carcinoma: the primary gastric-type (or gastro-intestinal type) carcinoma of the endometrium. This type of neoplasm tends to have a poor outcome, making its correct diagnostic important. As little is known about this entity and given its quite challenging diagnosis, we aim to review existing data about it and propose a practical diagnostic approach. There are currently 11 cases published in 8 articles fitting the precise definition of a primary gastric-type carcinoma of the endometrium. Three main differential diagnoses must be excluded before considering this tumor: endometrioid adenocarcinoma with mucinous (Müllerian-type) differentiation, endocervical primary, and gastro-intestinal primary. Morphological aspects of this tumor can be heterogeneous and confusing; in this context, immunochemistry can be helpful to highlight the gastric or intestinal differentiation, but also to eliminate a mucinous endometrioid adenocarcinoma of Müllerian-type, by the constant negativity of estrogen receptors. A metastasis of a primary gastro-intestinal tract carcinoma must also be excluded by clinical, endoscopic and imaging work-up. Finally, an endometrial extension of a primary endocervical gastric-type carcinoma should be ruled out by complete sampling of the cervix. Intestinal type endocervical adenocarcinoma is easier to eliminate since this is an HPV-associated neoplasm.

Variants of in situ carcinoma of the endometrium: Clear cell and gastrointestinal types, with a review of the literature

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In-situ lesions of endometrial carcinomas clear cell and intestinal types are not a well-recognized entity, although these exist.

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We’re describing three such lesions.

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We also discussed available English literature on this topic.

Two precursor lesions are commonly associated with endometrial carcinoma. Atypical endometrial hyperplasia/endometrial intraepithelial neoplasia is a known precursor lesion of endometrial endometrioid carcinoma, while endometrial intraepithelial carcinoma, is a recognized precursor lesion of endometrial high-grade serous carcinoma. Other than these two recognized entities, other rare precursor lesions for endometrial carcinoma do exist, although reported cases are relatively few and not universally recognized. This therefore poses diagnostic challenges in clinical practice. Here, we describe a series of rare precursor lesions of the endometrium identified at our institution, including clear cell and gastrointestinal variants, their morphologic and immunohistochemical characteristics, and review current literature regarding these variants. The information provided may guide the proper diagnosis and ultimately lead to effective clinical management in every-day practice.

Mucinous Proliferations of the Uterine Corpus: Comprehensive Appraisal of an Evolving Spectrum of Neoplasms

A variety of endometrial lesions may contain mucinous cells. Herein, the author reviews the literature on the classification and clinicopathologic significance of uterine corpus proliferations with a significant mucinous component, assesses the 2020 World Health Organization classification of such lesions, and presents a diagnostic framework. The key epithelial mucinous lesions include mucinous metaplasia, atypical mucinous glandular proliferation and mucinous carcinoma. Each of these categories are classifiable into "usual" and gastrointestinal subtypes, the latter being indicative of intestinal (presence of goblet cells) and/or gastric-type (abundant, pale eosinophilic or clear cytoplasm and well-defined cell borders) morphology. It has been proposed that at least focal expression of gastrointestinal immunohistochemical markers be required for all gastrointestinal type lesions, and for gastrointestinal type atypical mucinous glandular proliferation and carcinoma, minimality or absence of estrogen receptor expression, and the absence of an endometrioid component. Mucinous carcinomas of the usual type, in which >50% of the tumor is comprised of a mucinous component, are the most common. Morphologic subtypes include mucinous carcinoma with microglandular features and mucinous carcinoma with signet rings (signet ring carcinoma). Endometrioid carcinomas with a less than a 50% mucinous component are classified as endometrioid carcinoma with mucinous differentiation. Several studies have directly compared endometrioid and mucinous carcinomas, the latter presumably of the usual type, with respect to patient outcomes after treatment. All have found no difference in overall and disease free survival between these groups. However, three major studies have found mucinous carcinomas to be associated with a higher risk of lymph node metastases. Nineteen cases of mucinous carcinoma of the gastrointestinal type have been reported, and the limited data on their follow-up after primary treatment suggests that this subtype is more clinically aggressive and should accordingly be classified separately from mucinous carcinomas of the usual type. The morphologic spectrum of mucinous carcinoma of the gastrointestinal type is unclear and continues to evolve. Mucinous change, which may sometimes be extensive, may also be associated with papillary proliferation of the endometrium, adenomyoma of the endocervical type, atypical, and typical adenomyomas. In a curettage or biopsy, intestinal type mucinous epithelium may be indicative of any of the gastrointestinal lesions mentioned above, but may also represent samplings of uterine teratomas, yolk sac tumors, genital and extragenital adenocarcinomas with intestinal differentiation, or low-grade appendiceal mucinous neoplasms that secondarily involve the endometrium.

Uncommon and Difficult High-Grade Endometrial Carcinomas

This article presents features of uncommon high-grade endometrial carcinomas that often pose a significant diagnostic challenge. An update on undifferentiated and dedifferentiated endometrial carcinoma is first provided, followed by discussions on more recently defined entities such as mesonephric-like carcinoma of the endometrium and gastric-type endometrial carcinomas. Finally, endometrial carcinoma with germ cell or trophoblastic-like components is discussed.

Endometrial Gastric (Gastrointestinal)-type Mucinous Lesions: Report of a Series Illustrating the Spectrum of Benign and Malignant Lesions

With the recent elucidation of gastric-type lesions in the female genital tract (especially in the cervix), occasional cases of endometrial adenocarcinoma displaying gastric (gastrointestinal) differentiation have been reported, but they are currently not recognized as a distinct pathologic entity. We report 9 cases of endometrial mucinous lesions which exhibit gastric (gastrointestinal)-type features by morphology and immunohistochemistry, including 4 adenocarcinomas and 5 benign mucinous lesions, in patients aged 32 to 85. The adenocarcinomas showed gastric-type morphology in all 4 cases and goblet cells in 1, with a component of benign gastric-type mucinous glands in 1 case. Immunohistochemically, the adenocarcinomas were positive for CK7 (4/4), CEA (4/4), MUC6 (3/3), PAX8 (3/4), CK20 (2/4), CDX2 (2/4), and estrogen receptor (1/4). They were negative for Napsin A (0/3), with mutation-type p53 staining in 2/4 cases, block-type p16 positivity in 1/4, and scattered chromogranin-positive cells in 1/2. Targeted next-generation sequencing revealed nonsense mutation in RB1 gene for the case with block-positive p16. Follow-up was available in all adenocarcinoma cases and indicated aggressive behavior; 2 patients were dead of disease at follow-up of 7 months to 3 years, 1 was alive with progression at 9 months, and 1 was alive without disease at 7 months. The benign mucinous lesions (including the benign component in 1 adenocarcinoma) exhibited gastric-type morphologic features in 5/6 cases, goblet cells in 5/6, and Paneth-like neuroendocrine cells in 1/6. These benign mucinous lesions were associated with an endometrial polyp in 5/6 cases. Cytologic atypia was present in 2/6 cases and a lobular architecture resembling cervical lobular endocervical glandular hyperplasia in 4/6. Immunohistochemically, the benign mucinous lesions were positive for CK7 (5/5), CDX2 (5/6), estrogen receptor (4/5), MUC6 (4/5), CK20 (3/5), PAX8 (3/5), and CEA (2/4), with scattered chromogranin-positive cells in 4/4 cases; in all cases tested Napsin A was negative, p53 was wild-type and p16 was negative. We propose the term "endometrial gastric (gastrointestinal)-type adenocarcinoma" for this distinctive group of rare aggressive endometrial carcinomas. We believe that benign or atypical gastric (gastrointestinal)-type mucinous lesions are putative precursors for these adenocarcinomas, comparable to recognized premalignant gastric-type lesions in the cervix and the vagina. Future recognition and reporting of these gastric-type endometrial mucinous lesions will help delineate their pathogenesis and clinical significance.

Difficulties in diagnosis of a minimal deviation adenocarcinoma of uterine cervix diagnosed postoperatively: brief communication and literature review

PURPOSE

Rare minimal deviation adenocarcinoma (MDA) diagnosed postoperatively as incidental finding of a suspicious cervical lesion at laparoscopy, emphasizing it represents a diagnostic challenge mimicking both benign and malignant cervical lesions with often overlapping imaging characteristics-case report and literature review.

CASE PRESENTATION

35-year-old Gravida with primary infertility presented with a suspicious cervical lesion and complained about menorrhagia, hyper-/dysmenorrhea. Clinical examination was unremarkable, transvaginal scan presented a 42 × 38 × 28 mm sized cervical lesion (i.e. fibroid) without hypervascularization. Unexpectedly, the diagnosis of minimal deviation adenocarcinoma in tissue sample taken from suspicious cervical lesion at laparoscopy was revealed in final pathological report. According to suspected early stage of MDA a radical abdominal hysterectomy (PIVER III/IV), bilateral salpingo-oophorectomy, omentectomy, pelvic and para-aortic lymphadenectomy was scheduled. Final histology report confirmed: "MDA", G2, FIGO pT1b1, pN0 (0/23 LN) L0 V0 Pn0 R0.

RESULTS

Ultrasonography may indicate MDA throughout the examination of vascularization/echogenicity with possibility of mimicking benign lesions with similar characteristics. Magnetic resonance imaging shows no pathognomonic signs for MDA. Subsequently, a review of literature was conducted and main factors affecting the prognosis of MDA considering diagnostic tools, clinical stage, histopathological results and surgical protocols were analyzed.

CONCLUSIONS

Minimal deviation adenocarcinoma represents one of rare cervical adenocarcinomas without HPV-association. While it is crucial to differentiate benign from malignant lesions in this subtype, imaging characteristics often overlap and may not provide a specific diagnosis. Therefore, it should be considered in suspicious multicystic cervical lesions and inconclusive PAP-smear. Definitive diagnosis of this subtype should be based on cervical biopsy.

Gastric-Type Endometrial Adenocarcinoma: Report of Two Cases in Patients From the United States

Gastric-type adenocarcinomas of the uterine cervix have been described within the literature in detail; however, the description of gastric-type endometrial adenocarcinomas is a recent development, with only two cases originating from Japan in the world literature to date. According to these prior reports, the recognition of this pattern of differentiation is critical, as it is often associated with deep myoinvasion, positive regional lymph nodes, and poor outcome despite appropriate adjuvant treatment. We present two cases of endometrial adenocarcinoma with gastric-type differentiation in patients from the United States with superficial myoinvasion and positive patient outcomes. Gastric-type differentiation in endometrial adenocarcinomas is rare and likely underrecognized. Continued reporting of these cases is necessary to further understand the natural history and clinical implications of this entity.