Adenoid basal carcinoma of the uterine cervix: evolution of a distinctive clinicopathologic entity

Distinctive clinicopathological features and disease‑specific survival of adenoid cystic carcinoma and adenoid basal carcinoma in the lower female genital tract

Adenoid cystic carcinomas (ACCs) and adenoid basal carcinomas (ABCs) in the lower female genital tract are very rare. Data on the clinicopathologic features and survival outcomes of ACCs and ABCs in the lower female genital tract are limited to case reports and small case series studies. The present study systemically analyzed 233 cases, including 84 cervical ACCs, 78 cervical ABCs and 71 vulvar ACCs, to identify clinicopathologic features and survival factors in a population‑based Surveillance, Epidemiology and End Results (SEER) study. Whereas cervical ACCs and ABCs tend to occur in the elderly (median, 72 and 69 years, respectively), vulvar ACCs commonly occurred in patients a decade younger (median, 59 years). The majority of patients with cervical ABC had localized disease and almost all received surgery. In contrast, cervical and vulvar ACC patients tended to have higher stage disease, and a significant proportion of these patients received radiotherapy, with or without surgery. The 5‑year cause‑specific survival (CSS) rates for patients with cervical ACC were 69.3%, vulvar ACC 87.7% and cervical ABC 96.6%. The 5‑year overall survival (OS) rate for patients with cervical ACC was 59.2%, significantly worse than that of cervical ABC (88.3%; P=0.002) and vulvar ACC (81.2%; P=0.01). Increased age and high stage were significantly associated with a worse prognosis in patients with cervical and vulvar ACCs by univariate and multivariate analysis (P<0.05). Tumor stage was the only significant factor associated with 5‑year overall survival in patients with cervical ABC (P<0.05). The present data demonstrated that the distinctive clinicopathologic features and survival outcomes differed significantly among ACCs and ABCs in the lower female genital tract, thus providing a rationale for location/pathologic type‑based treatment modalities.

Application of p16 Immunohistochemistry and RNA In Situ Hybridization in the Classification of Adenoid Basal Tumors of the Cervix

Our understanding of adenoid basal tumors of the cervix has evolved over time. Most of the proliferations referred to as adenoid basal carcinoma have a clinically benign course--leading some to suggest the term "adenoid basal epithelioma." However, rarely, these may be associated with invasive carcinomas. These tumors have been etiologically linked with high-risk human papillomavirus (HR-HPV) infection. Here, we investigate the use of p16 immunohistochemistry and HR-HPV RNA in situ hybridization (ISH) in the classification of adenoid basal tumors of the cervix. Seventeen cases of adenoid basal tumors of the cervix were included. The patients' age ranged from 19 to 79 yr (average, 59 yr). p16 immunostain was performed on all cases and RNA ISH was performed in 4 cases with available formalin-fixed paraffin-embedded tissue. There were 11 low-grade tumors, 5 frankly invasive carcinomas, and 1 with histologic features that were intermediate between the former 2 categories. p16 immunostain was negative or showed patchy cytoplasmic staining in the low-grade tumors and was strongly and diffusely positive in the invasive carcinomas. HR-HPV RNA ISH was negative in the 3 low-grade tumors and was positive in 1 case of invasive carcinoma including the adenoid basal component. Distinct p16 immunostaining and HR-HPV RNA ISH patterns exist between low-grade adenoid basal tumors and invasive adenoid basal carcinomas. Our study indicates that p16 immunostaining and HR-HPV RNA ISH can be employed as useful ancillary tools in differentiating between noninvasive and invasive adenoid basal tumors along with careful histopathologic evaluation.

Adenoid basal carcinoma arising in the cervical polyp: an immunohistochemical study of stromal cells

Adenoid basal carcinomas of the uterine cervix are uncommon neoplasms and generally run a favorable clinical course. Although it is well known that these tumors do not evoke the stromal reaction, we immunohistochemically examined a stromal reaction in a case of adenoid basal carcinoma. A 40-year-old woman was found to have a cervical polyp during a medical checkup and underwent polypectomy. Histological examination revealed the finding of adenoid basal carcinoma. Immunohistochemically, a smaller number of CD34-positive and CD31-negative stromal cells, namely fibroblasts, in the stroma of tumor center than in normal cervical stroma were observed. On the other hand, alpha-smooth muscle actin-positive and h-caldesmon-negative stromal cells, namely myofibroblasts, were completely absent in the stroma of tumor center. Finally, our preliminary report suggests that the decrease of CD34-positive fibroblasts in adenoid basal carcinoma may show an early stromal reaction to tumor invasion. Gynecologists and pathologists should bear in mind that adenoid basal carcinoma may arise in a cervical polyp.

Adenoid basal lesions of the uterine cervix: evolving terminology and clinicopathological concepts

The epithelial proliferations that are designated adenoid basal carcinoma (ABC) in the current classification from the World Health Organization represent <1% of all cervical malignancies. These lesions may be associated, and occasionally show morphologic transitions with, conventional cervical malignancies. The determination of the precise frequency with which these so-called ABCs show this association is hampered by the inherent selection bias in the reported cases. However, this frequency appears to be substantial (>15%). The biologic course of ABCs that are associated with separate malignancies is largely dependent on the clinicopathologic parameters of the associated malignancies. Morphologically pure lesions, in contrast, have largely been associated with favorable patient outcomes, as none of the 66 reported patients have experienced tumor recurrence, metastases or tumor-associated death, irrespective of the modality of treatment. Although the finding of genome integrated high-risk human papillomavirus (HPV) types and p53 alterations in adenoid basal lesions (ABL) argue in support of their neoplastic nature, we identified no lines evidence that suggest an inherent malignancy for morphologically pure lesions. The finding of morphologic transitions between ABLs and conventional malignancies and shared HPV types in these areas, suggest that ABLs have some malignant potential. However, the precise magnitude of this potential is not readily quantifiable and should not dictate the management of morphologically pure lesions that are entirely evaluable. ABLs continue to occupy a unique position in human oncology in which the term carcinoma (without an in-situ suffix) is applied to a tumor that has not been shown to recur, metastasize or cause death. We concur with a previous proposal that the term ABC should be discarded and replaced with Adenoid Basal Epithelioma (ABE). In our opinion, there is insufficient evidence at present time to expose patients with morphologically pure lesions to the ominous implications--social, psychological, medical, financial--of a "carcinoma" diagnosis. Morphologically impure lesions should not be designated ABC or ABE. Furthermore, given the uncertainties regarding the frequency with which ABE are associated with separate malignancies, we suggest that the ABE designation only be applied when the tumor in question is entirely evaluable e.g in a hysterectomy specimen or in an excisional biopsy with negative margins. Otherwise, the generic designation Adenoid Basal Tumor is preferable. This approach strikes an appropriate balance between the need to prevent over-treatment of pure lesions on one hand, and the need to ensure that the lesions are indeed pure on the other.

Symposium part II: special types of adenocarcinoma of the uterine cervix

This report provides a comprehensive review of several special types of adenocarcinoma of the uterine cervix. The clinicopathologic features of three tumors that may cause difficulties in diagnosis are detailed: adenoid basal carcinoma (epithelioma), adenoma malignum (minimal deviation adenocarcinoma), and mesonephric adenocarcinoma. Updated information on classification and clinical behavior are presented, as is data on their histochemical, immunohistochemical, and molecular profiles.

Carcinosarcoma of the uterine cervix: a report of eight cases with immunohistochemical analysis and evaluation of human papillomavirus status

Carcinosarcomas (malignant Müllerian mixed tumors [MMMTs]) of the uterine cervix are rare neoplasms. This report describes the morphology, immunohistochemical profiles, and human papillomavirus (HPV) status of eight cervical MMMTs. Patients' ages ranged from 32 to 93 years (mean, 61 years). Seven cases showed in situ squamous cell carcinoma (SCC). The invasive epithelial component (EC) was composed of combined adenoid basal carcinoma, basaloid SCC, and adenoid cystic carcinoma (ACC) in two cases. Keratinizing SCC, large cell nonkeratinizing SCC, undifferentiated carcinoma, and basaloid SCC predominated in the remaining tumors, one of which had admixed ACC. The sarcomatous component (SC) was homologous and spindled with admixed myxoid areas in three lesions. The ECs and SCs in six MMMTs showed dual immunostaining with epithelial membrane antigen and the pan-keratin marker, MNF116. The SC was vimentin-positive in seven cases. Five tumors had a vimentin-positive EC. The SC was positive for muscle specific actin and/or smooth muscle actin in seven lesions, of which four were desmin-positive. Polymerase chain reaction (PCR) using GP5+/GP6+ L1 consensus primers detected HPV DNA in all eight cases. Nonisotopic in situ hybridization with digoxigenin-labeled probes to HPV types 6, 11, 16, 18, 31 and 33 demonstrated integrated HPV 16 in three cases, not only in the EC, but also in nuclei of the SC. This is the first study to implicate HPV in the evolution of cervical MMMTs. The above observations lend support to a metaplastic theory of histogenesis.

Adenoid cystic and adenoid basal carcinoma of the uterine cervix: comparative morphologic, mucin, and immunohistochemical profile of two rare neoplasms of putative 'reserve cell' origin

Adenoid cystic carcinomas (ACCs) and adenoid basal carcinomas (ABCs) are rare neoplasms of the uterine cervix that are currently regarded as distinct clinicopathologic entities. Accurate distinction between ABCs and ACCs is of clinical importance because of differences in their biological behavior. This study compares the morphologic, mucin, and immunohistochemical profiles of 18 cervical ACCs, 8 ABCs, and 1 combined ABC-ACC. Serial sections from the 27 cases were stained with hematoxylin and eosin, periodic acid-Schiff-diastase, mucicarmine, and alcian blue and subjected to a panel of immunoperoxidase markers, namely, MNF116, CAM 5.2, CK7, CK20, epithelial membrane antigen, carcinoembryonic antigen (CEA), S-100, HHF 35, laminin, and type IV collagen. One ACC was also examined ultrastructurally. Almost all patients were postmenopausal black women. The distinction between ABC and ACC was best made morphologically. Divergent epithelial differentiation was seen in 18 cases (11 ACCs, 6 ABCs, and 1 ABC-ACC). Six cases with intact surface epithelium showed a high grade squamous intraepithelial lesion. There was no significant difference in mucin staining. Both tumor types had a similar immunohistochemical profile, apart from type IV collagen and laminin staining, which occurred exclusively in relation to the extracellular basement membranelike material in the ACC. Eleven ACCs and three ABCs were S-100-positive, including the respective ACC and ABC components of the combined ABC-ACC. Eight of the S-100-positive neoplasms with ACC morphology also stained with HHF 35, suggesting myoepithelial differentiation. The latter was confirmed in one ACC examined ultrastructurally. The similar clinical profiles, apart from the different biological behavior, capacity for divergent differentiation, and the occurrence of ABC areas in some ACCs and vice versa suggest that these tumors may share a common histogenesis, forming part of a morphologic and biologic spectrum of basaloid cervical neoplasms of putative "reserve cell" origin. Circumstantial evidence suggests that ABC may be a precursor of cervical ACC.