MN Protein Immunolocalization in Uterine Cervix Carcinoma With Glandular Differentiation: A Clinicopathologic Study of a New Cancer-specific Biomarker

MN protein is the product of the newly described endogenous MN gene that is expressed in the tumorigenic phenotype of HeLa X fibroblast somatic cell hybrids. MN protein has carbonic anhydrase and putative DNA binding activity. With the exception of gastric mucosa, MN protein is expressed in neoplasia, particularly uterine cervix carcinoma, but not in benign tissue. This investigation examined the pathogenetic and prognostic significance of MN-protein immunoreactivity in uterine cervix carcinoma with glandular differentiation. Paraffin sections from 77 cervix carcinomas with glandular differentiations including 36 pure adenocarcinomas and 41 adenosquamous carcinomas were immunostained with anti-MN-protein (M-75 monoclonal proprietary; Ciba Corning Diagnostics, Alameda, CA). A total of 64.9% of cervix carcinomas with glandular differentiation exhibit MN-protein immunoreactivity localized to plasma membranes, cytoplasm, and some nuclei of neoplastic cells only, but not in adjacent benign tissue. The MN-protein staining intensity and distribution was as follows: 37.7% strong diffuse (≥ 50% cells positive), 19.5% strong focal (< 50% cells positive), and weak (7.8%). Immunoreactivity occurred in both squamous and glandular areas of adenosquamous carcinomas and was unrelated to histopathologic features. Follow-up information was available on 67 patients: 31 exhibited recurrent disease (7 pelvic, 14 distant, and 10 both) at 1–144 months (mean 37, median 14), and 36 were disease-free at 12–216 months (mean 67, median 44.5). MN-protein immunoreactivity (all positives, both standard diffuse and strong focal, or standard diffuse only) exhibited no association with clinical outcome. Recurrent disease was associated with nuclear grade ( P < .001), lymphatic invasion ( P < .005), size on clinical examination or pathologic evaluation ( P < .005), pelvic lymph node involvement ( P < .05), and clinical stage ( P < .05). MN-protein immunoreactivity did not correlate with these features and did not help predict which patients would develop recurrence in the good prognosis groups. Our data show that expression of MN-protein is associated with cervix carcinoma with glandular differentiation carcinogenesis. MN-protein immunolocalization may have a diagnostic role in confirming cervix carcinoma with glandular differentiation in histologically challenging cases.

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.

Severe cervical glandular cell lesions with coexisting squamous cell lesions

BACKGROUND

In the current report, the authors present the results of a reevaluation of cytologic smears and histologic specimens obtained from patients with severe cervical glandular cell lesions (adenocarcinoma in situ [AIS] or adenocarcinoma [ADCA] of the cervix) and coexisting Grade 1, Grade 2, or Grade 3 cervical intraepithelial neoplasia or squamous cell carcinoma. The goal of the current study was to assess whether knowledge of the specific cytologic characteristics of the cervical glandular cell lesions could have made the cytologic diagnosis of these combined neoplasms more accurate.

METHODS

Cytologic smears and histologic specimens obtained from 36 patients with combined severe cervical lesions were evaluated for the presence of a range of microscopic cytologic and histologic features that were considered indicative of glandular cell changes.

RESULTS

The findings of the current study suggest that the proper identification of characteristic cytomorphologic features of cervical glandular lesions would have resulted in more accurate diagnoses of combined severe cervical lesions. In the set of samples reevaluated by the authors, consideration of these features would have increased the accuracy of cytologic diagnosis from 55.6% to 75.0%. The presence of AIS was predicted in the majority of cytologic specimens, and in most cases, the identity of the predominant subtype of AIS could also be predicted.

CONCLUSIONS

The current analysis revealed that consideration of specific cytomorphologic features of glandular lesions of the cervix increased the authors' accuracy in diagnosing combined severe lesions of the cervix. More accurate identification of intraepithelial glandular cell lesions may eventually lead to decreases in cervical adenocarcinoma incidence, just as increases in diagnostic accuracy have led to decreases in the incidence of squamous intraepithelial lesions and invasive squamous carcinoma of the cervix.

Endocervical adenocarcinoma and its variants: their morphology and differential diagnosis

Adenocarcinoma of the uterine cervix and its variants account for a much greater number of cases in routine practice of histopathology than they did several decades ago. The varied morphology of these tumours results in diverse problems in differential diagnosis. The overall area of glandular pathology of the cervix, of which invasive adenocarcinoma is only one subset, is further complicated by the fact that there are many benign glandular proliferations of the cervix that can potentially be misinterpreted as adenocarcinoma. In this review the histopathology of endocervical adenocarcinoma and its variants is presented with the emphasis on evaluation of routinely stained sections, still the bedrock of routine practice, relatively little aid being provided by immunohistochemistry or other new techniques, contrary to what is sometimes implied in the literature. Description of the appearance of each subtype of adenocarcinoma or variant thereof is followed by a section on their differential diagnosis. Eighty percent of endocervical carcinomas are of the so-called usual type being characterized by cells with eosinophilic cytoplasm and generally brisk mitotic activity. It is sometimes stated that endocervical adenocarcinomas are mucinous but the usual form just noted often has little or no mucin. Pure or almost pure mucinous adenocarcinoma do occur, however, and have an important subtype, the so-called adenoma malignum (minimal deviation adenocarcinoma). Although treacherous because of its bland cytological features and sometimes deceptive pattern, a cone biopsy or hysterectomy specimen showing this neoplasm typically has easily recognizable features that indicate the presence of an infiltrative adenocarcinoma. An important variant of usual endocervical adenocarcinoma is the well differentiated villoglandular papillary adenocarcinoma, a designation that should be reserved for tumours with grade 1 cytologic features as usual endocervical adenocarcinoma, which is typically grade 2, may have papillae. In our opinion all other variants of pure adenocarcinoma, including endometrioid, are rare and include in addition to the latter clear cell, serous and mesonephric neoplasms. Tumours with a glandular and nonglandular component are also reviewed: adenosquamous carcinoma, glassy cell carcinoma, adenoid basal carcinoma, 'adenoid cystic' carcinoma and adenocarcinoma admixed with a neuroendocrine tumour.

Cervical carcinoma with glandular differentiation: histological evaluation predicts disease recurrence in clinical stage I or II patients

Pathologists confront questions concerning the clinical implications of the more complex, evolving histopathologic classification in cervical carcinoma with glandular differentiation (CCGD) and the associated precursor intraepithelial lesions. Pseudoneoplastic pitfalls, such as microglandular hyperplasia, constitute the subject of recent reports, but the extent of misinterpretation for CCGD is unknown. To address these issues, we retrospectively reviewed all the histopathologic material for 67 patients treated for early clinical stage (I or II) CCGD. Two patients (3%) had pseudoneoplastic glandular lesions (two microglandular hyperplasias). The remaining 65 CCGDs included 35 pure adenocarcinomas (18 mucinous, six serous, five endometrioid, five clear cell, and one adenoid cystic), 26 adenosquamous carcinomas (17 showed > or = 50% and nine showed > 10% but < 50% squamous differentiation-all nonkeratinizing; four were predominantly glassy cell type, and the others showed the following adenocarcinoma component differentiation: 11 mucinous, eight serous, and three endometrioid) and four villoglandular papillary adenocarcinomas (all four were mucinous). In situ carcinoma was identified in 54%. The two patients with pseudoneoplastic lesions were disease free (after 96 and 108 months). Twenty-one patients with CCGD had recurrent disease at 4 to 144 months (mean, 45; median, 18) including three local recurrences, 10 with distant metastasis, and eight with both. Thirty-five patients with CCGD were disease free at 12 to 216 months follow-up (mean, 80.6; median, 65). Adenosquamous (P < .0002, predictive value [PV] = .68) and serous differentiation (P < .05, PV = .61) were the only histological types associated with disease recurrence. Vascular space invasion (P < .0002, PV = .7), deeper invasion (P < .0005), nuclear grade (P = .002, PV = .51), larger tumors on clinical exam (P < .01) or pathological evaluation (P < .01), and presence of pelvic lymph node metastasis at surgery (P < .05, PV = .7) are additional features associated with recurrent disease. A combination of adenosquamous or serous differentiation and vascular space invasion maximized PV for recurrent disease at a level of .75. Mucinous, endometrioid, or clear cell histological types, architectural grade, or the distinction between clinical stages I and II were not associated with recurrent disease. None of the four patients with villoglandular papillary adenocarcinoma exhibited recurrent disease, but confirmation of this histological subtype's prognostic value was hindered by the small number of cases identified (P = .16). Adenosquamous and serous differentiation, nuclear grading, pathological evaluation of vascular space and lymph node involvement, and recognition of pseudoneoplastic glandular lesions helped predict recurrent disease in low clinical stage CCGD in this retrospective study.