A pre-tailored panel of antibodies in the study of cervical mesonephric remnants

Incidental mesonephric remnant hyperplasia of the jejunal mesentery: A diagnostic challenge

Mesonephric remnants are embryonic vestiges of the mesonephric (Wolffian) ducts which regress during normal development. These remnants have been uncommonly reported in the female and male reproductive tract as a spectrum of morphologic lesions that can be misdiagnosed as carcinoma. One case of mesonephric remnant hyperplasia of the jejunal mesentery incidentally found in a 47-year-old man is herein reported. This is the first description of mesonephric hyperplasia arisen in the mesentery. The presence of ducts, tubules, and cysts lined by bland, epithelial, cuboidal cells with scant cytoplasm, and diffuse pseudoinfiltrative growth pattern can raise the possibility of neoplasia. Immunohistochemically, mesonephric epithelia have a characteristic staining. CD10 highlights the apical-luminal aspect of the cells. Besides, intense reactivity is showed for high-molecular-weight cytokeratin (CK), CK7, bcl2, and vimentin. The main differential diagnosis includes mesothelial hyperplasia, epithelial mesothelioma, well-differentiated neuroendocrine tumor, and infiltration due to acinar adenocarcinoma of the prostate. However, a detailed microscopic study with the aid of immunohistochemistry helps separate mesonephric remnants from malignant processes. The mesonephric hyperplasia of the mesentery we have reported adds to the spectrum of mesonephric remnants a new location. Familiarity with this lesion is indispensable to avoid overdiagnosis.

Cervical clear cell adenocarcinoma with an exceptionally low proliferation index: Report of a case

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A histologically low-grade cervical clear cell lesion was observed.

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Proliferating cells were seen only at the periphery of this lesion.

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Due to its low proliferation index, this may represent a precursor of clear cell carcinoma.

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Further definition of such lesions may allow for more minimal management.

Differential Expression Patterns of GATA3 in Uterine Mesonephric and Nonmesonephric Lesions

GATA binding protein 3 (GATA3) is a recently described immunohistochemical marker that has proven useful in the characterization of breast and urothelial carcinomas. However, the expression pattern of GATA3 in mesonephric proliferations is largely unknown. The aim of this study was to examine the immunohistochemical expression of GATA3 in cervicovaginal mesonephric lesions and compare it to its expression in endocervical and endometrial adenocarcinomas and cervicovaginal endometriosis. A cohort of 107 cases, including 33 cases of mesonephric lesions and 74 cases of nonmesonephric lesions, was selected for the study. Of 33 mesonephric lesions, 31 (94%) cases (16 remnants, 12 hyperplasias, and 3 adenocarcinomas) were strongly and diffusely positive in tumor cell nuclei for GATA3. The remaining 2 mesonephric carcinosarcomas showed focal nuclear staining and rare nuclear positivity, respectively. Of 36 endocervical adenocarcinomas, 33 (92%) were negative for GATA3 and the remaining revealed focal weak nuclear staining. Of 34 endometrial adenocarcinomas, 32 (94%) were negative, whereas 2 showed rare nuclear positivity. All 4 cases of endometriosis were negative. The benign endocervical epithelium and the benign endometrium in most cases lacked GATA3 expression, whereas the benign squamous epithelium in the majority exhibited nuclear basal and parabasal staining pattern. Our study demonstrates that GATA3 protein is expressed in most mesonephric lesions, regardless of them being benign or malignant. In contrast, GATA3 is absent in the majority of endometrial and endocervical adenocarcinomas. These results support that GATA3 immunostain can be a useful tool in differentiating mesonephric lesions from endocervical and endometrial adenocarcinomas.

GATA3 Is a Sensitive and Specific Marker of Benign and Malignant Mesonephric Lesions in the Lower Female Genital Tract

GATA3 is a transcription factor critical for embryogenesis, development, and cell differentiation. Recent studies have suggested that GATA3 is a sensitive and relatively specific biomarker for urothelial and breast carcinomas, with most Müllerian carcinomas being negative. We investigated GATA3 expression in mesonephric/Wolffian remnants and tumors in the female genital tract. A western blot was performed to assess specificity for the GATA3 antibody. GATA3 immunohistochemistry was performed on 59 formalin-fixed paraffin-embedded mesonephric samples, including 17 mesonephric remnants (MR; 11 cervical and 6 fallopian tube), 15 mesonephric hyperplasias, 21 mesonephric carcinomas, and 6 female adnexal tumors of probable Wolffian origin. Thirty conventional endocervical adenocarcinomas (ENDO-CA), 9 gastric-type cervical adenocarcinomas, and 165 endometrial adenocarcinomas (EM-CA) were also evaluated. GATA3 nuclear intensity and extent of staining was evaluated. The western blot revealed GATA3 expression in seminal vesicle and cell lines derived from breast and urothelial carcinomas, but not in other cell lines including ovarian, cervical, and endometrial cancers. All cervical MRs and mesonephric hyperplasias, 5/6 (83%) fallopian tube MRs, and 20/21 (95%) mesonephric carcinomas were GATA3 positive, although with great variability in both intensity (weak to strong) and extent (1+ to 3+) of staining. Only 1/6 (17%) female adnexal tumors of probable Wolffian origin showed weak multifocal staining. One of 30 (3%) usual-type ENDO-CAs and 3/165 EM-CAs exhibited weak-moderate GATA3 immunoreactivity; all gastric-type cervical adenocarcinomas were negative. GATA3 is a highly sensitive and specific marker for mesonephric lesions in the lower genital tract; however, its utility in the upper genital tract may be more limited. In addition, GATA3 can aid in distinguishing lower genital mesonephric lesions from usual-type and gastric-type ENDO-CAs and uterine EM-CAs.

Differential patterns of PAX8, p16, and ER immunostains in mesonephric lesions and adenocarcinomas of the cervix

Mesonephric remnants, usually located deep in the lateral cervical wall, may become hyperplastic resulting in a florid proliferation. These can be misinterpreted as malignant and confused with endocervical adenocarcinomas. Recent data have shown that PAX2 is diffusely expressed in mesonephric remnants and hyperplasias. PAX8 is a related transcription protein that is expressed in tissues of müllerian and wolffian origin. In this study, we have investigated the utility of an immunohistochemical panel comprising of PAX8, estrogen receptor (ER), and p16 in the differential diagnosis between mesonephric proliferations and cervical adenocarcinomas. A database search was conducted for cases of mesonephric remnants/hyperplasia/carcinoma of cervix and invasive cervical adenocarcinomas. Immunohistochemical stains for PAX8, ER, and p16 were performed using the avidin-biotin peroxidase technique on the most representative tissue. The search yielded 28 cases of mesonephric proliferations of cervix (15 mesonephric remnants, 12 mesonephric hyperplasias, and 1 mesonephric adenocarcinoma) and 16 cases of cervical adenocarcinomas (15 usual type and 1 adenoma malignum). Immunohistochemically, all the mesonephric proliferations, regardless of being benign or malignant, displayed a consistent staining pattern-diffusely and strongly positive for PAX8, negative for ER, and patchy cytoplasmic staining for p16. The usual type cervical adenocarcinomas exhibited a variable staining pattern with PAX8 and ER but all were strongly and diffusely positive for p16. The case of adenoma malignum was PAX8 positive, ER negative, and showed weak and patchy staining with p16. Our study suggests that a panel of immunohistochemical stains composed of PAX8, p16, and ER is useful in the distinction between mesonephric proliferations and cervical adenocarcinomas.

The spectrum of cervical glandular neoplasia and issues in differential diagnosis

CONTEXT

Premalignant and malignant glandular lesions of the cervix are known to often cause diagnostic problems with a variety of benign (more common) as well as other malignant mimics, the latter setting often being represented by secondary involvement by endometrioid endometrial carcinoma especially in small samplings.

OBJECTIVE

To highlight key histologic features and immunohistochemical markers that may be helpful in the distinction of in situ endocervical carcinoma from benign glandular proliferations, and those that separate different subtypes of invasive endocervical carcinoma, as well as invasive carcinoma from other carcinomas secondarily involving the cervix and nonneoplastic proliferations of the cervix.

CONCLUSIONS

Clinical and morphologic features as well as immunohistochemistry results should be used in conjunction in the differential diagnosis of glandular proliferations of the cervix, as correct interpretation has major clinical consequences for the patient in most instances (especially benign versus malignant). Immunohistochemical markers should be used as part of a panel of antibodies, as exceptions may occur to the usual pattern of staining, and if used singly, they may mislead the pathologist to establish a wrong diagnosis.

A retroperitoneal cyst with unusual urinary histogenesis: clinical and immunomorphological characteristics

Primary retroperitoneal cysts are rare benign lesions which often present as an incidental radiological finding and also cause abdominal symptoms. A 47-year-old woman was admitted to the surgery unit because of right-sided abdominal pain. Computed tomographic scan investigation confirmed a circumscribed, oval, dishomogeneous mass in the right anterior pararenal space. The final diagnosis was obtained after laparotomy excision and pathological evaluation. Immunohistochemical profile was characterized by positive expression of epithelial cystic cells for CKAE1/AE3, CK7, CK8, and CK18, with EMA sustaining the diagnosis of a benign retroperitoneal cyst of urinary system origin.