Malignant adenomyoepithelioma combined with adenoid cystic carcinoma of the breast: a case report and literature review

Primary mucoepidermoid carcinoma of the breast arising in adenomyoepithelioma

Mucoepidermoid carcinoma (MEC) and adenomyoepithelioma (AME) are uncommon neoplasms of the breast that are more commonly noted in the salivary glands. AMEs are benign tumours that are known to undergo malignant transformation. This report describes the first case of a MEC arising in AME in a woman in her 50s.

Papillary Neoplasms of the Breast: Diagnostic Features and Molecular Insights

Papillary neoplasms of the breast are a heterogeneous group of tumors characterized by fibrovascular cores lined by epithelium, with or without myoepithelial cells. Papillary neoplasms include benign, atypical, and malignant tumors that show varying histopathologic features and clinical outcomes. Appropriate pathologic classification is crucial to guide clinical treatment. Classification of papillary neoplasms is largely based on morphology, with immunohistochemistry playing an ancillary role to establish diagnoses. Recent molecular studies have provided insight into the genomics of these lesions. This review summarizes the histologic, immunohistochemical, and molecular features of papillary neoplasms of the breast that are important for diagnosis and treatment.

Special Histologic Type and Rare Breast Tumors - Diagnostic Review and Clinico-Pathological Implications

Breast cancer is the most common malignant tumor in females. While most carcinomas are categorized as invasive carcinoma, no special type (NST), a diverse group of tumors with distinct pathologic and clinical features is also recognized, ranging in incidence from relatively more common to rare. So-called "special histologic type" tumors display more than 90% of a specific, distinctive histologic pattern, while a spectrum of tumors more often encountered in the salivary gland may also arise in the breast. Metaplastic carcinomas can present diagnostic challenges. Some uncommon tumors harbor pathognomonic genetic alterations. This article provides an overview of the key diagnostic points and differential diagnoses for this group of disparate lesions, as well as the salient clinical characteristics of each entity.

Combination of Adenomyoepithelioma and Adenoid Cystic Carcinoma of the Breast: A Case Report of an Uncommon Histopathological Entity

BACKGROUND Adenomyoepithelioma and adenoid cystic carcinoma are uncommon types of breast tumors. Adenoid cystic carcinoma accounts for 0.1% of breast neoplasms and typically presents as a tender breast tumor, mostly in the subareolar area. Adenoid cystic carcinoma usually appears in women in the fifth or sixth decade of life and predominantly presents as a mixed tumor, with cribriform, tubular, and solid growth characteristics. Adenomyoepithelioma of the breast shows epithelial and smooth muscle characteristics. Adenomyoepithelioma rarely goes through malignant transformation and is an uncommon type of benign breast tumor. CASE REPORT Our study reviews the current published literature regarding the combination of these 2 rare neoplasms of the breast and shows a rare case of a 48-year-old woman with a combination of adenoid cystic carcinoma and adenomyoepithelioma. CONCLUSIONS The combination of adenoid cystic carcinoma and adenomyoepithelioma should be part of the differential diagnosis in breast cancer. More research is needed regarding the optimal therapy, which is currently surgical excision.

Diagnostic challenges of adenomyoepithelioma: A case report

INTRODUCTION

Breast adenomyoepithelioma is a very uncommon tumor, which is generally considered to be benign, however malignant transformation has been reported.

PRESENTATION OF CASE

We report two cases of two women with breast adenomyoepithelioma.

CONCLUSION

Diagnosis of adenomyoepithelioma is challenging because tumor may mimic other breast diseases. It has neither specific clinical signs nor radiological features, and the diagnosis is based on histopathological examination of the lesion. The treatment of choice is surgery. The type of surgery depends on the tumor factors and breast size. In malignant cases treatment such as radiotherapy, chemotherapy, immunotherapy may be used as well. It is very important to give an adequate treatment, otherwise the risk of tumor recurrence, growth or even metastatic spread, when tumor has malignant potential, increases.

Malignant adenomyoepithelioma of the breast: Two case reports and review of the literature

BACKGROUND

Malignant adenomyoepithelioma (AME) of the breast is a rare tumor in which malignancy can arise from either epithelial or myoepithelial components, or from both cell types. The incidence and prognosis of malignant AME of the breast are difficult to assess due to its rarity. Therefore, the optimal treatment for this disease is still controversial.

CASE SUMMARY

We present two middle-aged women (48 and 56 years old) with malignant AME of the breast. Core needle biopsy was performed before surgery. However, breast adenoma and malignant tumors were observed. The preoperative diagnosis of malignant AME of the breast is still challenging for pathologists and clinicians. Both patients underwent mastectomy and sentinel lymph node biopsy, both of which were negative, followed by adjuvant chemotherapy.

CONCLUSION

The follow-up duration of the two patients was two years and four months, respectively. No signs of relapse or metastasis have been observed thus far.

Adenoid cystic carcinoma and basaloid carcinoma of the breast: A clinicopathological study

Adenoid cystic carcinoma of the breast (ACCB) is a rare triple negative tumor (TNT) with an excellent prognosis in most cases. Three different histologic types are recognized: classic ACCB, solid basaloid ACCB (SB-ACCB), and ACCB with high-grade transformation. A majority of these tumors show characteristic molecular and immunohistochemical (IHC) features, with fusion of MYB and NFIB genes and overexpression of MYB, respectively. Basaloid carcinomas of the breast (BCB) are infrequently described. They resemble SB-ACCB and TNT of no special type (TNT-NST). We have studied the clinicopathological features of 17 ACCB and 9 BCB, investigating the expression of MYB by IHC and the rearrangements of MYB by fluorescence in situ hybridization (FISH). MYB was expressed by IHC in 15 ACCB and in 3 BCB. MYB FISH detected rearrangements in 11 ACCB and in 2 BCB. After a mean follow-up of 90 months, with a range of 12-204 months, 2 patients with ACCB with high-grade transformation and 1 patient with BCB developed metastases and died of disease. In summary, most ACCB have a good prognosis, but tumors with adverse histopathological features may metastasize. BCB may overlap with ACCB and TNT-NST, and their prognosis should be further studied.

Cutaneous adenomyoepithelioma with histopathological heterogeneity: A case report

Some skin adnexal tumors display both epithelial and myoepithelial cell populations and can be broadly categorized as biphasic tumors. These include apocrine hidrocystoma, mixed tumor, adenomyoepithelioma (AME), and adenoid cystic carcinoma (ACC). Myoepithelioma is the myoepithelial cell-predominant type in this category. Cutaneous AME is exceedingly rare and usually has a benign prognosis, but it is considered to have the potential for local recurrence and metastasis. We report the case of a 57-year-old man with a 1-year history of an ulcerated nodule on his scalp. Microscopically, it was a defined cutaneous nodule with a focal lobulated architecture, composed of epithelial cells forming ducts and myoepithelial cells distributed around the ducts. In addition to these findings of typical AME, the present case focally revealed atypical features, such as increased mitotic activity (7/10 high power fields), invasive growth, and necrosis. However, cytological atypia was not significant. We conclusively diagnosed cutaneous AME with atypical features, suggesting malignant potential. Moreover, areas showing appearances similar to apocrine hidrocystoma, mixed tumor, myoepithelioma, and ACC were focally observed. We present a unique case of cutaneous AME exhibiting histopathological heterogeneity. The recognition of morphological variation could be helpful in appropriately diagnosing and treating AME of the skin.

Triple-negative breast carcinomas of low malignant potential: review on diagnostic criteria and differential diagnoses

Triple-negative breast carcinomas constitute a wide spectrum of lesions, mostly being highly aggressive. Nevertheless, some special histologic subtypes can have low malignant potential. The purpose of the present paper is to review diagnostic criteria and prognostic parameters of breast neoplasms of special histotypes. Specifically, adenoid cystic carcinoma, adenomyoepithelioma, acinic cell carcinoma, mucoepidermoid carcinoma, tall cell carcinoma with reverse polarity, and secretory carcinoma will be discussed. For each tumour, definition and morphological and molecular features, together with prognostic parameters, will be presented. Paradigmatic cases will be illustrated.

Adenomyoepithelial tumors of the breast: molecular underpinnings of a rare entity

Adenomyoepitheliomas (AMEs) of the breast are uncommon and span the morphologic spectrum of benign, atypical, in situ, and invasive forms. In exceptionally rare cases, these tumors metastasize to regional lymph nodes or distant sites. In the era of genomic characterization, data is limited regarding AMEs. The aim of this study was to provide insight into the molecular underpinnings of a spectrum of AMEs. Seven cases of AMEs of the breast (benign-1, atypical-2, in situ-1, invasive-3) were identified in our files. The seven samples were interrogated using the Oncomine Comprehensive Assay v3 (ThermoFisher). Two atypical AMEs and the malignant in situ AME harbored the same gain-of-function PIK3CA mutation. The malignant in situ AME also showed EGFR amplification, not described previously. Both a benign AME and a malignant invasive AME shared the same gain-of-function AKT1 variant. The benign AME also showed a GNAS mutation. Moreover, the same gain-of-function HRAS mutation was present in an atypical AME and a malignant invasive AME. We also identified co-occurring HRAS and PIK3CA mutations in an ER-positive atypical AME, which has not been previously described. No fusion drivers were detected. We describe the molecular characteristics of the spectrum of AME tumors of the breast, which harbor alterations in the PI3K/AKT pathway. Our findings are clinically relevant with respect to the current options of targeted therapy in the rare instances where malignant AME tumors of the breast progress.

36 cases adenoid cystic carcinoma of the breast in China: Comparison with matched grade one invasive ductal carcinoma-not otherwise specified

OBJECTIVE

The aim of this study was to investigate the clinicopathological characteristic of adenoid cystic carcinoma (ACC).

MATERIALS AND METHODS

The clininopathological features, along with relapse free survival(RFS) and overall survival(OS) of 36 patients with ACC were retrospectively investigated and compared with those of 108 grade 1 invasive ductal carcinoma not-otherwise-specified (G1-IDC-NOS) patients.

RESULTS

Most cases of ACC were ER, PR and HER-2 negative which was classified as triple-negative subtype. Five cases were concomitant with other pathological types of cancer. Axillary lymph node dissection(ALND) was performed in 31 patients and 2 of them with lymph nodes metastasis. Two patients died of lung metastases at 46 and 116 months after the surgery respectively. Compared with G1-IDC-NOS, ACC showed lower Ki-67 index, less lymph nodes metastasis, lower P53 expression, and higher proportion in location of upper outer quadrant of breast. There was no difference of OS and RFS between ACC and G1-IDC-NOS.

CONCLUSIONS

ACC of the breast was a rare disease with a good prognosis although most of them were classified as triple-negative subtype. And the value of axillary node dissection and adjuvant therapy needs to be further investigated.