Immunohistochemical features of carcinoma ex pleomorphic adenoma and pleomorphic adenoma in the lacrimal gland

Dendritic cell subpopulations in carcinoma ex-pleomorphic adenoma: A multicenter study

OBJECTIVE

Carcinoma ex-pleomorphic adenoma (CEXPA) represents a malignant transformation from a recurrent or primary pleomorphic adenoma (PA), and the immune response may be essential in this process. Therefore, in this study, we aimed to identify and quantify subpopulations of dendritic cells (DCs) in CEXPA, residual PA in CEXPA (rPA), and PA.

MATERIALS AND METHODS

A multicenter study was performed collecting salivary gland tumor (SGT) samples from three Oral and Maxillofacial Pathology Centers. A tissue microarray containing 41 samples of CEXPA and 22 samples of PA was included in this study and submitted to immunohistochemical reactions against CD1a, CD83, CD207, and Ki67 antibodies.

RESULTS

Both PA and rPA showed a higher quantification of CD207+ and CD83+ cells when compared to CEXPA (p < 0.001 and p < 0.01, respectively). There was also a difference when comparing the cell proliferation index between PA/rPA and CEXPA using the Ki-67 marker (p = 0.043). However, there was no difference in the DC population regarding clinical parameters such as sex, anatomical location, size, and metastases (p > 0.06).

CONCLUSIONS

Immunohistochemical profile of DC subpopulations and cell proliferation biomarkers in SGTs can contribute as an important tool in the differentiation of benign and malignant tumors or detection of initial areas with malignant transformation.

A rare case of mucoepidermoid carcinoma ex-pleomorphic adenoma of the hard palate

Carcinoma Ex-Pleomorphic Adenoma (CExPA) is a salivary gland carcinoma derived from a primary or recurrent benign pleomorphic adenoma (PA) extremely rare in minor salivary glands. In this paper, we report the case of a male afrodescendant patient, 37 years old, presenting a palatal irregular nodular lesion with approximately 3.5 cm diameter. The lesion had over two years of evolution, but started growing faster and presenting pain and ulceration in the last two months. The incisional biopsy revealed a typical pleomorphic adenoma with focal areas of nests of epidermoid and mucous cells, as well as microcyst formations, resembling the mucoepidermoid carcinoma (MEC). Immunohistochemical analysis revealed positivity for CK7, CK13, CK 14, p63 and Ki67 (about 30%), whereas α-SMA was restricted to the PA component. The diagnosis was CExPA (MEC-type). A discussion on the histopathological and immunohistochemical criteria for differential diagnosis of CExPA is provided in this work, hoping to contribute to a better knowledge and understanding of this rare malignant tumor. Key words:Salivary gland neoplasms, pleomorphic adenoma, adenocarcinoma, mucoepidermoid carcinoma, pathology, differential diagnosis.

Carcinoma Ex Pleomorphic Adenomas: An Institutional Experience and Literature Review

OBJECTIVES

To provide an institutional experience with cases diagnosed as carcinoma ex pleomorphic adenoma (CXPA), including the cytologic and histologic findings and clinical follow-up, followed by a comparison to the experience documented in the literature.

METHODS

We identified cases of CXPA diagnosed at our institution from 2011 to 2021 and reviewed the cytologic and histologic diagnoses, as well as the treatment and clinical outcomes. Additionally, a literature review of the English literature was performed on CXPAs from 2011 to 2021.

RESULTS

Forty-one cases of CXPA were identified, with the majority subclassified as adenocarcinoma, not otherwise specified. Five tumors underwent cytogenetic studies and five underwent molecular studies. To date, 36 patients are alive, 8 of whom experienced locoregional recurrence or distant metastasis.

CONCLUSIONS

Our institutional experience was comparable to that reported in the literature. Further studies are required to inquire about the role of molecular profiles of CXPAs in clinical risk assessment.

Mucoepidermoid Carcinoma Ex Pleomorphic Adenoma of Lacrimal Gland: Case Report and Review of Literature

Carcinoma ex pleomorphic adenoma (Ca ex PA) is defined as an infiltrative carcinoma arising from a primary or recurrent benign pleomorphic adenoma. Ca ex PA with the histologic subtype mucoepidermoid carcinoma is extremely uncommon. Only 2 previous reports in the lacrimal gland have been documented. We reported a 55-year-old lady with a firm, solid, nontender mass in the supralateral quadrant of the right orbit at the area of the lacrimal gland. After wide excision of mass, pathology revealed high-grade mucoepidermoid carcinoma Ex pleomorphic adenoma. To reduce tumor recurrence 60 Gray radiation was delivered to the orbital cavity. She is still tumor-free 1 year after completion of treatment.

Proptosis Revealing a Rare Lacrimal Gland Tumor: A Case of Chondroid Syringoma in a 35-year-old Patient

Lacrimal gland chondroid syringoma is a very rare tumor with classic clinico-radiological symptoms that should be familiar to clinicians for appropriate patients’ management as the tumor has potential for recurrence and malignant transformation. We report herein a case of chondroid syringoma in a 35-year-old patient presenting with progressive painless proptosis for 2 years. He underwent complete surgical removal of the tumor, with subsequent clinical improvement of his symptoms.

Retrospective Analysis of Clinicopathological Characteristics of Lacrimal Gland Pleomorphic Adenoma and Mechanism of Tumorigenesis by the Imbalance Between Apoptosis and Proliferation

BACKGROUND Lacrimal gland pleomorphic adenoma (LGPA) is the most common clinically benign epithelial tumor of the lacrimal gland and is predominantly comprised of epithelial cells and interstitial components. At present, the exact pathogenesis of LGPA remains unclear. Previous research has indicated that the occurrence of LGPA may be related to excessive cell proliferation. MATERIAL AND METHODS This study observed the clinicopathological characteristics of LGPA and investigated the tumorigenesis mechanism of cell over-proliferation caused by the imbalance between apoptosis and proliferation. A total of 27 cases were collected from the Department of Ophthalmology of the Affiliated Hospital of Chengde Medical University and the Third Medical Center of Chinese PLA General Hospital from April 2017 to November 2019. Hematoxylin-eosin (HE) staining and immunohistochemical staining were used to observe the pathological characteristics and analyze the expression of bcl-2 and bax in the lacrimal gland. RESULTS Compared with normal lacrimal gland tissues, LGPA tumor tissues had obvious changes in pathological morphology. The expression of bcl-2 in LGPA lesion tissues was dramatically higher (P<0.001), the expression of bax was not significantly different between groups (P=0.25), but the ratio of bcl-2/bax was significantly higher in tumor tissues (P=0.01). CONCLUSIONS We found that the lacrimal gland tumor tissues had obvious excessive proliferation in pathomorphology, which revealed the necessity of complete surgical removal of the capsule from the perspective of pathological morphology and provided a theoretical basis for the hypothesis that the imbalance between apoptosis and proliferation could lead to cell hyperproliferation.

Ductal Adenocarcinoma Ex Pleomorphic Adenoma of the Lacrimal Gland: a Rare and Morbid Malignancy

Carcinoma ex pleomorphic adenoma (Ca ex PA) is a rare malignant transformation of a benign primary pleomorphic adenoma (PA). We report the case of a 62-year-old male who presented with a swelling over his left temple. Imaging revealed a lytic lesion over the left orbital wall with soft tissue extension suggestive of malignancy. He underwent an en bloc resection of the mass with orbital exenteration, craniotomy, and reconstruction. Pathology demonstrated a lacrimal gland ductal adenocarcinoma arising from a PA which led to the diagnosis of ductal adenoCa ex PA. Postoperatively, he received chemotherapy with 6 cycles of cisplatin and concurrent radiation therapy (RT), but his course was complicated by recurrent bacterial meningitis and abscesses and he ultimately opted for comfort measures. Patients with PA of the lacrimal gland experience an insidiously enlarging painless swelling of the orbit with transformation to Ca ex PA highlighted by a rapid onset of bulbar enlargement, displacement, and often proptosis. Ductal adenoCa ex PA is aggressive with a poor prognosis and has no established standard of care. This case highlights the rarity of this condition and the need for more literature to help direct treatment.