Noninvasive and minimally invasive carcinoma ex mixed tumor: a clinicopathologic and ploidy study of 12 patients with major salivary tumors of low (or no?) malignant potential

Hypoxia-Induced Biosynthesis of the Extracellular Matrix Molecules, Perlecan and Fibronectin, Promotes the Growth of Pleomorphic Adenoma Cells In Vitro Models

Salivary pleomorphic adenoma is histopathologically characterized by its colorful stroma with myxoid, chondroid, and hyaline appearances, due to enhanced biosynthesis of extracellular matrix (ECM) molecules and poor vascularity. Thus, pleomorphic adenoma cells embedded in the stroma typically survive under hypoxic conditions. We determined the expression kinetics of ECM molecules, such as perlecan and fibronectin (FN), under hypoxia in SM-AP1 cells which are duct epithelial differentiated cells, and in SM-AP4 cells, which are myoepithelial differentiated cells, cloned from pleomorphic adenoma of the parotid gland. We investigated hypoxia-inducible factor-1α (HIF-1α)-inducing pathways through a variety of ECM molecules in association with their cellular proliferation and migration. We observed that hypoxic conditions with elevated HIF-1α protein levels induced increased expression of perlecan and FN in SM-AP cells than in controls. Moreover, perlecan and FN knockdown reduced the proliferation of SM-AP1 and SM-AP4 cells under hypoxia. Further, SM-AP1 cell migration was enhanced by both perlecan and FN knockdown, whereas SM-AP4 cell migration was increased by perlecan knockdown and inhibited by fibronectin knockdown. The results indicated that pleomorphic adenoma cells can survive under hypoxic conditions by promoting cell proliferation via enhanced synthesis of ECM molecules. Overall, ECM molecules may be a new anti-tumor target under hypoxic conditions.

Data Set for the Reporting of Carcinomas of the Major Salivary Glands: Explanations and Recommendations of the Guidelines From the International Collaboration on Cancer Reporting

The International Collaboration on Cancer Reporting is a nonprofit organization whose goal is to develop evidence-based, internationally agreed-upon standardized data sets for each anatomic site, to be used throughout the world. Providing global standardization of pathology tumor classification, staging, and other reporting elements will lead to achieving the objective of improved patient management and enhanced epidemiologic research. Salivary gland carcinomas are relatively uncommon, and as such, meaningful data about the many histologic types are not easily compared. Morphologic overlap between tumor types makes accurate classification challenging, but there are often significant differences in patient outcomes. Therefore, issues related to tumor type, tumor grading, high-grade transformation, extent of invasion, number and size of nerves affected, and types of ancillary studies are discussed in the context of daily application to specimens from these organs. This review focuses on the data set developed for salivary gland carcinomas with discussion of the key core and noncore elements developed for inclusion by an international expert panel of head and neck and oral-maxillofacial pathologists and surgeons.

Increased SOX2 expression in salivary gland carcinoma ex pleomorphic adenoma progression: an association with adverse outcome

SOX2 is a regulatory factor of embryonic stem cells that has been implicated in carcinogenesis and cancer progression. We aimed to investigate the potential role of SOX2 in the stepwise progression from pleomorphic adenoma (PA) to invasive carcinoma ex pleomorphic adenoma (CXPA), evaluating its prognostic significance as well. Thirty PAs without malignant transformation and 25 CXPAs presenting both luminal or myoepithelial differentiation (7 intracapsular and 18 extracapsular) were evaluated immunohistochemically for SOX2 expression. Of these, 24 CXPAs (96%) were positive to SOX2, being 6 intracapsular carcinomas (85.7%) and all the 18 extracapsular carcinomas (100%). Residual PA areas and PA without malignant transformation were negative. High SOX2 expression levels (> 50% of positive cells) were correlated with high histological grade (p = 0.02), brisk mitotic activity (p = 0.01), advanced pT stage (p = 0.01), tumor recurrence (p = 0.01), and development of distant metastasis (p = 0.004). Still, overall survival rates were shorter in patients with extracapsular CXPA exhibiting diffuse SOX2 expression. These results suggest that SOX2 may play an important role in carcinogenesis and progression of CXPA and is also related with prognostic indicators in CXPAs with extracapsular invasion. Although direct therapeutic intervention in SOX2 may result in unwanted complications due to its constitutive functions, strategic approach to SOX2-related pathways may provide new therapeutic opportunities for patients with invasive CXPA.

A Case Report of Rare Carcinoma Ex Pleomorphic Adenoma of Submandibular Gland and its Detailed Description

A 65-year-old female patient reported with a chief complaint of swelling in the left lower region of the jaw since two years. On clinical examination, the swelling was present on the mandibular left posterior region and measuring approximately 6.2 cm antero-posteriorly × 6.2 cm mediolaterally × 8.7 cm superioinferiorly. Initially, it was non tender but eventually it became tender. Fine needle aspiration was done to rule out any salivary gland pathology and report obtained was carcinoma ex pleomorphic adenoma. Then, excisional biopsy was taken and tissue sent for histopathology. Histopathological diagnosis was benign adenoma with carcinoma. Later serial sections of tissue were studied and came to the conclusion of carcinoma ex pleomorphic adenoma which was non invasive type and showed bizarre cells with neoplastic changes. Benign part was composed of myxomatous area with partial capsule. Neoplastic cells showed invasion into capsule and few necrotic areas were also present. Overall interpretation was favoured Non invasive carcinoma ex pleomorphic adenoma. So here, we reported a case of Carcinoma ex Pleomorphic Adenoma (CAEXPA) which is a deadly and rare variant of salivary gland malignancy.

Expression of cancer/testis antigens in salivary gland carcinomas with reference to MAGE-A and NY-ESO-1 expression in adenoid cystic carcinoma

AIMS

Cancer/testis antigens (CTAs) are detected in cancer cells but not in healthy normal tissues, with the exception of gametogenic tissues. CTAs are highly immunogenic proteins, and thus represent ideal targets for cytotoxic T-lymphocyte-mediated specific immune therapy. The aim of this study was to screen CTA expression in various types of salivary gland carcinoma and to clarify clinicopathological significance of MAGE-A and NY-ESO-1 expression in adenoid cystic carcinomas (AdCCs) of the salivary gland, which is one of the most common salivary gland carcinomas, and usually has a fatal outcome.

METHODS AND RESULTS

We used immunohistochemistry to examine the expression of four CTAs (MAGE-A, NY-ESO-1, CT7, and GAGE7) in various types of salivary gland carcinoma (n = 95). When carcinoma cases were divided into low-grade and intermediate/high-grade types, NY-ESO-1 and CT7 were expressed more frequently in intermediate/high-grade carcinomas. We then focused on MAGE-A and NY-ESO-1 expression in a large cohort of adenoid cystic carcinomas (AdCCs) (n = 46). MAGE-A and NY-ESO-1 were frequently expressed in AdCC; specifically, MAGE-A was expressed in >60% of the AdCC cases. MAGE-A expression and tumour site (minor salivary gland) were identified as independent risk factors for locoregional tumour recurrence.

CONCLUSIONS

These findings suggest that CTAs may be expressed in a variety of salivary gland carcinomas, especially in those with higher histological grades. In addition, MAGE-A, which is frequently expressed in AdCC cases, may be a useful prognostic factor for poorer locoregional recurrence-free survival.

Histological, immunohistological and molecular characteristics of intraductal precursor of carcinoma ex pleomorphic adenoma support a multistep carcinogenic process

In recent years, multistep carcinogenesis of carcinoma ex pleomorphic adenoma (CEPA) has been identified, starting with intraductal neoplasia within pre-existent pleomorphic adenoma (PA). However, as yet there is no consensus regarding clinical relevance and appropriate terminology of precursor lesions in CEPA. We therefore decided to investigate precursor lesions, especially intraductal carcinoma, in a series of 85 cases of CEPA. Intraductal carcinoma confined by benign myoepithelial cells was found in 60 cases and mostly exhibited high-grade cellular atypia, increased cellular proliferation and frequent genetic alterations (TP53, Her2-neu, androgen receptor). Intraductal carcinoma was absent only in the myoepithelial type of CEPA. In 26 cases, purely intraductal CEPA with extensive intraductal expansion was found. This suggests that there is a long period of intraductal growth before extraductal intracapsular infiltration of the PA. We identified two different histomorphological types of intraductal carcinoma, which we call 'clinging' and 'solid' types. In summary, combined histological, immunohistological and molecular data strongly support multistep carcinogenesis starting with intraductal carcinoma for all non-myoepithelial types of CEPA. The clinical significance of our finding of two histomorphological types of intraductal carcinoma (clinging and solid) is not yet clear. Intraductal carcinoma, intracapsular invasive CEPA and minor extracapsular invasive CEPA (up to about 6 mm) all show favourable prognosis and together comprise half of the cases in our study.

Biomarker Analysis in Carcinoma ex Pleomorphic Adenoma at an Early Phase of Carcinomatous Transformation

Diagnostic criteria for intracapsular carcinoma ex pleomorphic adenoma (CXPA) are subjective and vary among authors. Biomarker analysis, which could provide more objective evaluation of these tumors, has rarely been studied in intracapsular CXPA. Immunohistochemical evaluation of c-erbB-2, p53 protein, bcl-2, and Ki-67 was performed in 8 cases of CXPA at an early phase of malignant transformation (4 intracapsular and 4 minimally invasive) and in 17 pleomorphic adenomas (PA). In all cases of CXPA, p53 and Ki-67 were demonstrated predominantly in luminal cells of benign and malignant areas, significantly more in the latter. Few benign myoepithelial cells were p53 positive. c-erbB-2 reactivity was strongly associated with atypical luminal cells. Bcl-2 expression was weak and focal in malignant areas from 2 cases. In conclusion, both p53 and c-erbB-2 proteins appear to be involved at an early stage of malignization of PA. In PA with atypical cells, evaluation of the expression of these 2 markers provides more objective criteria for the diagnosis of intracapsular CXPA.

Minimally invasive carcinosarcoma ex pleomorphic adenoma: A case report and literature review with cytohistological correlation

BACKGROUND

Carcinosarcoma of the salivary glands is a rare neoplasm, and the minimally invasive form constitutes a subgroup with a more favorable prognosis. The cytomorphologic features of this neoplasm can be appreciated on fine-needle aspiration biopsy.

METHODS AND RESULTS

We present a patient with a minimally invasive carcinosarcoma ex non-recurrent pleomorphic adenoma (Ca ex PA) who underwent initial fine-needle aspiration biopsy followed by surgical resection. The tumor was composed predominantly of a light microscopic pleomorphic high-grade sarcoma exhibiting partial myoepithelial immunohistochemical features, with a minor component of in situ and invasive salivary duct carcinoma (10%). A limited area with features of a hyalinized pleomorphic adenoma was identified.

CONCLUSION

This is the third case report of the cytological features of Ca ex PA of the salivary gland, with histologic correlation. It further illustrates the oncogenic relationship between epithelial and myoepithelial elements in the early stages of carcinosarcomatous transformation. © 2016 Wiley Periodicals, Inc. Head Neck 38: E2483-E2489, 2016.

Carcinoma Ex Pleomorphic Adenoma: Is It a High-Grade Malignancy?

PURPOSE

The objective of this study was to investigate the clinicopathologic features of carcinoma ex pleomorphic adenoma (CXPA) and comprehensively improve an understanding of this disease.

MATERIALS AND METHODS

This retrospective study investigated 151 cases of histologically confirmed CXPA. Disease-specific survival, local recurrence, and regional and distant metastases were analyzed.

RESULTS

Most cases were classed as frankly invasive CXPA (135 of 151). More than half these cases (73 of 135; 54.1%) developed local recurrence; 25 (18.5%) developed cervical metastasis; 21 (15.6%) developed distant metastasis; and 60 patients (55.6%) died during follow-up. In contrast, only 1 patient in the noninvasive CXPA group (n = 10) died after treatment for lung metastasis and 1 patient developed cervical metastasis. Similarly, only 1 patient in the minimally invasive CXPA group (n = 6) died of lung metastasis and the remaining 5 patients had an uneventful recovery after treatment.

CONCLUSIONS

Frankly invasive CXPA was a high-grade malignancy with an unfavorable prognosis. Elective neck dissection should be performed in cases of frankly invasive CXPA that originate in the submandibular gland. Patients with minimally invasive and noninvasive CXPA should be followed closely after primary treatment because regional or distant metastasis can occur.

The Stem Cell Marker Bmi-1 Is Sensitive in Identifying Early Lesions of Carcinoma ex Pleomorphic Adenoma

In the present study, we evaluated and described the sensitivity of the stem cell marker B cell-specific moloney murine leukemia virus integration site 1 (Bmi-1) in identifying early lesions of carcinoma ex pleomorphic adenoma (CXPA). While invasive CXPAs are tumors with a prominent and easily recognizable malignant component, the identification of early carcinomatous changes in PA remains a diagnostic challenge due to the lack of objective morphological criteria. The immunohistochemical expression of Bmi-1 was assessed in both adenomatous and carcinomatous components of 9 CXPA cases at an early phase of histological progression (6 intracapsular and 3 minimally invasive) grouped according to the cellular differentiation as luminal (7 cases) or myoepithelial (2 cases). A selective nuclear expression of Bmi-1 was found exclusively in the malignant component of 8 cases (6 luminal type and 2 myoepithelial type), including intraductal carcinoma areas, except for 1 case in which scarce cells of the remnant PA were positive. Thus, Bmi-1 is expressed from the earliest morphologically detectable stages of PA malignant transformation. When faced with atypical features in PA, evaluation of Bmi-1 expression can provide more objective criteria for identification and diagnosis of early lesions of CXPA. This is applied to carcinomas with luminal or myoepithelial differentiation.

A Rare Case of Mucoepidermoid Carcinoma ex Pleomorphic Adenoma arising in Minor Salivary Gland: Histopathological and Immunohistochemical Analysis

Mucoepidermoid carcinoma ex pleomorphic adenoma (MCxPA) is a rare salivary gland tumor predominantly found in major salivary glands. A case of MCxPA involving the soft tissue and bone of the retromolar region of a 26-year-old man is presented. The histopathological features revealed a neoplasm with predominance of pleomorphic adenoma (PA) elements, and presence of mucoepidermoid carcinoma malignant epithelial cells in several areas. Histochemical and immunohistochemical studies were positive for periodic acid Schiff, alcian blue, cytokeratins 7, 13, 14, and 19, Bcl-2, c-erbB-2, FGF-2 and maspin in the malignant areas. The patient underwent a partial resection of the left side of the mandible with neck dissection and MCxPA diagnosis was confirmed.

Consistent PLAG1 and HMGA2 abnormalities distinguish carcinoma ex-pleomorphic adenoma from its de novo counterparts

Carcinoma ex-pleomorphic adenoma (CA ex-PA) is a malignant salivary gland tumor that arises in association with pleomorphic adenoma (PA). Both PA and CA ex-PA have a broad spectrum of histology, and distinction from their histologic mimics may be difficult based on morphology alone. PLAG1 and HMGA2 abnormalities are the most common genetic events in both PA and CA ex-PA; however, the use of PLAG1 and HMGA2 as adjunct molecular tests has not been well established. Fluorescence in situ hybridization for PLAG1 and HMGA2 was performed on 22 CA ex-PA (10 myoepithelial carcinomas [MECAs], 10 salivary duct carcinomas [SDCs], 1 carcinoma with squamoglandular features, and 1 mixed MECA-adenocarcinoma not otherwise specified), 20 de novo carcinomas (11 MECAs and 9 SDCs), 16 PAs, and 11 PA-histologic mimics. All except 3 CAs ex-PA (86%) were positive for PLAG1 or HMGA2 rearrangements/amplifications. In contrast, 18 (90%) of 20 de novo carcinomas lacked abnormalities in PLAG1 or HMGA2 (P < .01). PLAG1 or HMGA2 rearrangements were identified in 6 (67%) of 9 hypocellular myxoid PAs and in 2 (29%) of 7 cellular PAs. Furthermore, all morphologic mimics of PA were negative for PLAG1 or HMGA2. PLAG1 and HMGA2 rearrangements are the most common genetic events in CA ex-PA regardless of the histologic subtype. Unlike CA ex-PA, de novo carcinomas were negative for PLAG1 and HMGA2. Interestingly, rearrangements of PLAG1/HMGA2 were identified in most hypocellular PAs but only in a small subset of cellular PAs. Fluorescence in situ hybridization for PLAG1 or HMGA2 can be used to distinguish between PA and CA ex-PA and their morphologic mimics.

Carcinoma ex pleomorphic adenoma of the palate composed of invasive micropapillary salivary duct carcinoma and adenoid cystic carcinoma components: an unusual case with immunohistochemical approach

Carcinoma ex pleomorphic adenoma (CXPA) is an unusual epithelial malignancy that develops from a primary or recurrent pleomorphic adenoma (PA), the most common tumor of salivary glands, and constitutes about 11.5% of all carcinomas that affect these glands. Intraoral minor salivary glands and seromucous glands of the oropharynx are uncommon locations of CXPA. On histopathological examination, the tumor comprises a wide morphological spectrum with a variable proportion between the benign and malignant components with the latter often predominating and overlapping the PA, which may cause misdiagnosis. Here, we report a case of palatal minor salivary gland CXPA composed of invasive micropapillary salivary duct carcinoma and adenoid cystic carcinoma components with multiple nodal metastases in a 74-year-old woman. Neoplastic cells showed heterogeneous immunohistochemical profile with both luminal and myoepithelial differentiation. The invasive micropapillary salivary duct carcinoma component demonstrated overexpression of the oncoprotein human epidermal growth factor receptor-2. This feature should be considered and evaluated as a possible target for adjuvant therapy in case of metastatic disease.

Salivary duct carcinoma and the concept of early carcinoma ex pleomorphic adenoma

AIMS

The data on the histological type of carcinomatous component and the extent of extracapsular invasion for salivary carcinomas ex pleomorphic adenoma (PA) are conflicting. We aimed to determine the prognostic value of extracapsular invasion in salivary duct carcinomas (SDC) ex PA.

METHODS AND RESULTS

A total of 117 patients with SDC were identified retrospectively; 44 cases involving major salivary glands had pre-existing PA (44 of 117, 37%). The morphological spectrum of SDC ex PA was characterized. The primary endpoint was overall survival (OS). Most SDC ex PA were widely invasive at presentation (27 of 44; 61%). Five patients with intracapsular SDC ex PA experienced no disease progression. The assessment of extracapsular invasion was precluded in eight cases (e.g. positive margins of resection). The rate of lymph node involvement was similar in cases with extracapsular invasion of ≤2 mm (two of three) and >7 mm (22 of 26). Only pT correlated with OS [116 months, 95% confidence interval (CI) 22-210 months for pT1 versus 20 months (95% CI 6-34) for pT4; P = 0.013].

CONCLUSIONS

Intracapsular SDC ex PA are potentially indolent. SDC ex PA with extracapsular invasion of ≤2 mm are rare, and appear to be clinically aggressive. Several histological parameters preclude assessment of extracapsular invasion.

Clinical outcome of patients with carcinoma ex pleomorphic adenoma of the parotid gland: a comparative study from a single tertiary center

BACKGROUND

Carcinoma ex pleomorphic adenoma (CXPA) of the parotid gland is a high-grade cancer and the prognosis of this cancer has not been compared with non-CXPA high-grade primary parotid cancer.

METHODS

Retrospective medical chart review of patients with surgically treated high-grade primary parotid cancer (21 CXPA and 52 non-CXPA) was performed with correlation with disease-specific survival, locoregional recurrence, and distant recurrence.

RESULTS

Despite having similar stage of cancer and extent of surgical resection, patients with CXPA had a lower disease-specific survival compared to non-CXPA high-grade primary parotid cancer (p = .02). Salivary duct cancer (SDC) was the commonest histologic variant in both cohorts and around 40% of patients with SDC died of distant recurrence that occurred within 3 years from diagnosis.

CONCLUSION

CXPA of the parotid gland is a more aggressive cancer compared to non-CXPA high-grade primary parotid cancer. SDC was associated with a high chance of delayed distant recurrence, which contributed directly to the mortality of this cancer.

Prognostic factors affecting the clinical outcome of carcinoma ex pleomorphic adenoma in the major salivary gland

BACKGROUND

Carcinoma ex pleomorphic adenoma (CXPA) is an uncommon malignant tumor with highly aggressive biological behavior. Our goal was to investigate the prognosis of CXPA in the major salivary glands and factors influencing it.

METHODS

We retrospectively reviewed 51 patients diagnosed with CXPA of the major salivary glands between 1999 and 2006, comprising 36 males and 15 females, aged from 23 to 86 years. All patients underwent surgery with curative intention, and 21 received postoperative radiation therapy.

RESULTS

Of the 51 patients, 39.2% developed locoregional recurrence and 27.5% developed distant metastases. Median follow-up was 54 months. At the time of analysis, 29 (56.9%) patients were deceased. Overall survival was 62.7% at 3 years and 50.3% at 5 years. Tumor-specific survival was 64.4% at 3 years and 53.5% at 5 years. Using chi-squared tests, invasiveness, T stage, lymph node involvement and clinical stage were found to be significantly associated with locoregional recurrence. Histological grade, invasiveness, lymph node involvement and perineural invasion were associated with distant metastases (P < 0.05). Cox analysis showed that T stage, lymph node involvement, histological grade and perineural invasion were independent prognostic factors for overall survival.

CONCLUSION

T stage, lymph node involvement, histological grade, perineural invasion and extent of invasion are important prognostic factors of CXPA in the major salivary glands. Surgery is the primary treatment modality for CXPA and postoperative radiation therapy may be used in patients with factors for poor prognosis.

Carcinoma ex pleomorphic adenoma, with particular emphasis on early lesions

Carcinoma ex pleomorphic adenoma (CXPA) is a broad category of carcinomas of the salivary glands which includes at least 2 clinically relevant categories; one is referred here as early CXPA (ECXPA), the other as widely invasive CXPA. The former includes several histological patterns ranging from non-invasive/in situ/intraductal/intratubular, early invasive/extratubular/intracapsular and extracapsular (up to 6 mm). The latter includes any CXPA with invasion of >6 mm. The clinical behaviour of ECXPA is not aggressive and tends to overlap that of a pleomorphic adenoma (PA) which makes the histological report of carcinoma contradictory. These early malignant changes in PA are known since the 1970s but it has been the use of immunohistochemical and molecular genetic analysis for HER-2 and TP53 gene in the last decade that has clarified the genuine malignant nature of the cells. HER-2 and TP53 gene and protein are involved in the early stages of malignant transformation of PA. Moreover the immunohistochemical over-expression HER-2, p53 protein and Mib-1 proliferation marker may be useful markers to identify malignant areas in PA.

[Malignant mixed tumors of the parotid gland: a review of the Department of Otolaryngology Medical University of Warsaw experience]

OBJECTIVES

Pleomorphic adenoma (PA), or benign mixed tumor, is the most common salivary gland neoplasm. One of the factors influencing the management strategy in parotid PA is the risk of malignant transformation of this tumor. The objective of this study was the clinical and pathological analysis of malignant mixed tumors treated surgically at the Department of Otolaryngology, Medical University of Warsaw.

MATERIALS AND METHODS

Retrospectively analysed clinical material included 12 patients with malignant mixed tumors selected from the group of 423 patients who underwent surgical treatment for parotid pleomorphic adenoma at the Department of Otolaryngology, Medical University of Warsaw, between January 1988 and June 2010. There were 7 women and 5 men; age ranged from 39 to 67 years, with a mean of 56 years. The following parameters were analysed: demographic data, symptoms and disease duration, results of diagnostic tests, intraoperative data, results of histopathological examination, and adjunctive therapy. Four patients with a follow-up shorter than 5 years were excluded from the analysis of treatment results.

RESULTS

A group of 12 patients with malignant mixed tumours included 10 (83.3%) cases of a primary tumor and 2 (16.7%) cases of a recurrent tumor. In the complete study sample (n=423), patients with malignant mixed tumor comprised: 2.8% of all patients, 2.5% of patients with primary PA and 5.1% of patients with recurrent PA. Patients with malignant mixed tumor were significantly older than patients with benign PA (an average patient age was 56.0 and 43.2 years, respectively p<0.001). 83.3% (n=10) patients were older than 50 years. An average disease duration was longer in patients with malignant tumors. Considering all data from preoperative patient assessment (medical history, physical examination, FNAB, imaging studies), a preliminary diagnosis of malignant disease was made in 6 (50%) patients. All patients were treated surgically and 10 also had radiation therapy. The group of patients (n=8), subjected to evaluation of treatment results, included three patients with non-invasive carcinoma and five patients with invasive carcinoma. All patients with non-invasive carcinoma were free from disease symptoms during the follow-up of 9 to 21 years after the treatment. Five-year survival was 80% (4 of 5 patients) in a group of patients with invasive carcinoma. The rate of death for the underlying disease was the same (80%). An overall 5-year survival in patients with malignant mixed tumor was 87.5%.

CONCLUSIONS

1. Malignant transformation of pleomorphic adenoma more frequently occurs in recurrent tumors and in older patients. 2. Uncharacteristic clinical picture of malignant mixed tumors allows to make an accurate initial diagnosis only in half of the patients. 3. Extracapsular cancer invasion is a vital prognostic factor. Overall 5-year survival for invasive and noninvasive carcinoma was 80 % and 100 % respectively.

Carcinosarcoma ex non-recurrent pleomorphic adenoma composed of TTF-1 positive large cell neuroendocrine carcinoma and myofibrosarcoma: apropos a rare Case

We present a carcinosarcoma ex non-recurrent pleomorphic adenoma composed of a large cell neuroendocrine carcinomatous component and a spindle cell sarcoma with myofibroblastic differentiation. The tumor contained a hyalinized transition zone where the classical PA appeared to acquire two different histopathological patterns of malignant transformation of the epithelial component. The carcinomatous component was strongly and diffusely positive for low-molecular weight cytokeratins (AE1-3), synaptophysin, thyroid transcription factor-1 and focally positive for chromogranin A. All these markers were negative in the sarcomatous component. The sarcomatous component displayed immunoreactivity for smooth muscle actin with a predominantly linear, subplasmalemmal pattern. No expression of CD31, S100 protein, h-caldesmon, desmin, CD34, p63, myogenin, Myo D1 and c-kit was detected. Strong immunohistochemical expression of p53 was documented in both the carcinomatous and sarcomatous components as well as in the atypical epithelial component in the transition zone associated with the hyalinized pleomorphic adenoma.

Carcinoma ex pleomorphic adenoma with special reference to the prognostic significance of histological progression: a clinicopathological investigation of 41 cases

AIMS

To investigate a large series of cases of carcinoma ex pleomorphic adenoma (CEPA) to determine prognostic factors.

METHODS AND RESULTS

Thirty cases of CEPA associated with primary pleomorphic adenoma (PA) and 11 cases of CEPA associated with recurrent PA were investigated. The median follow-up was 57.7 months, and ranged from 4 to 156 months. Purely intraductal carcinoma was found in 15 cases. Intraductal and extraductal intracapsular carcinoma together was found in one case. Extracapsular carcinoma was found in 25 cases. Prognosis was good for CEPA that was purely intraductal, extraductal intracapsular, or up to 5 mm extracapsular, and poor for CEPA that was 8 mm or more extracapsular. There were relatively more cases of CEPA with extracapsular invasion of 8 mm or more from recurrent PA than from primary PA, and the prognosis for CEPA associated with recurrent PA was worse than that for CEPA associated with primary PA.

CONCLUSIONS

The threshold for distinguishing minor extracapsular invasion with good prognosis from wide extracapsular invasion with poor prognosis is 5 mm. The worse prognosis for CEPA associated with recurrent PA indicates the necessity for close surveillance of patients with recurrent PA.

Disseminated carcinoma ex pleomorphic adenoma in an adolescent confirmed by application of PLAG1 immunohistochemistry and FISH for PLAG1 rearrangement

A 16-year-old previously asymptomatic boy presented with complaints of fatigue, weight loss, and back pain for several months. Imaging studies revealed a large superior mediastinal mass, numerous bilateral pulmonary nodules, and multiple lytic bone lesions. A needle biopsy from a sternal lesion showed a poorly differentiated carcinoma, immunoreactive for cytokeratins and EMA and immunonegative for various organ/tissue-specific markers.His past medical history was significant for excision of aparotid gland tumor 5 years earlier. Histologic review of the salivary gland tumor revealed a pleomorphic adenoma containing a microscopic focus of invasive carcinoma(carcinoma ex pleomorphic adenoma). By immunohistochemistry, both the salivary gland tumor and the disseminated carcinoma expressed PLAG1 with a strong nuclear pattern.Fluorescence in situ hybridization (FISH), using dual-color, break-apart probes for PLAG1, showed rearrangement of the gene in both the salivary gland and the disseminated tumors.FISH demonstrated additional cytogenetic aberrations in the carcinoma, including polysomy for chromosome 8 (in both the primary salivary gland and the metastatic tumors) and PLAG1 amplification (in the metastatic tumor). We conclude that in the proper clinicopathologic setting, application of PLAG1 immunohistochemistry and FISH for PLAG1 gene rearrangement may be valuable in establishing the diagnosis of carcinoma ex pleomorphic adenoma as the source of a cancer of unknown primary site.

Common Malignant Salivary Gland Epithelial Tumors

Malignant salivary gland epithelial tumors are histologically diverse with at least 24 recognized distinct entities. In general, malignant tumors account for 15% to 30% of parotid tumors, 40% to 45% of submandibular tumors, 70% to 90% of sublingual tumors, and 50% of minor salivary tumors. Common malignancies include mucoepidermoid carcinoma, adenoid cystic carcinoma, acinic cell carcinoma, salivary duct carcinoma, carcinoma ex pleomorphic adenoma, polymorphous lowgrade adenocarcinoma, and myoepithelial carcinoma. Each tumor type has its own unique histologic variants and prognostic pathologic features, and only mucoepidermoid carcinomas have a formalized grading system. The molecular pathogenesis of certain tumors, such as mucoepidermoid carcinoma and adenoid cystic carcinoma, has recently begun to be elucidated.

Carcinoma ex pleomorphic adenoma: a comprehensive review of clinical, pathological and molecular data

Carcinoma ex pleomorphic adenoma (Ca ex PA) is a carcinoma arising from a primary or recurrent benign pleomorphic adenoma. It often poses a diagnostic challenge to clinicians and pathologists. This study intends to review the literature and highlight the current clinical and molecular perspectives about this entity. The most common clinical presentation of CA ex PA is of a firm mass in the parotid gland. The proportion of adenoma and carcinoma components determines the macroscopic features of this neoplasm. The entity is difficult to diagnose pre-operatively. Pathologic assessment is the gold standard for making the diagnosis. Treatment for Ca ex PA often involves an ablative surgical procedure which may be followed by radiotherapy. Overall, patients with Ca ex PA have a poor prognosis. Accurate diagnosis and aggressive surgical management of patients presenting with Ca ex PA can increase their survival rates. Molecular studies have revealed that the development of Ca ex PA follows a multi-step model of carcinogenesis, with the progressive loss of heterozygosity at chromosomal arms 8q, then 12q and finally 17p. There are specific candidate genes in these regions that are associated with particular stages in the progression of Ca ex PA. In addition, many genes which regulate tumour suppression, cell cycle control, growth factors and cell-cell adhesion play a role in the development and progression of Ca ex PA. It is hopeful that these molecular data can give clues for the diagnosis and management of the disease.

Carcinoma ex pleomorphic adenoma of the nasal cavity

BACKGROUND

Carcinoma ex pleomorphic adenoma (CXPA) is a malignant epithelial neoplasm arising in a benign mixed tumor (i.e., pleomorphic adenoma or PA); it accounts for approximately 3-4% of all salivary gland neoplasms. CXPA is exceedingly rare in the nasal cavity, with only three cases previously documented.

METHODS

We report two cases of women presenting with masses of the nasal cavity. The tumors were resected and evaluated grossly and by routine microscopy.

RESULTS

Both patients presented with nasal obstruction, and one patient reported epistaxis. Grossly, the tumors were 2.5 and 3 cm in greatest dimension, respectively. In each case, microscopic examination of the tumor revealed an infiltrating carcinoma arising in association with foci of benign PA. The carcinoma types were adenoid cystic carcinoma and high grade adenocarcinoma, not otherwise specified. Both cases were widely (i.e., >1.5 mm) invasive beyond the preexisting PA. The findings were diagnostic of CXPA.

CONCLUSIONS

Carcinomatous transformation of a PA in the nasal cavity is extremely rare, but does occur. Accordingly, PAs of this site should be thoroughly sampled and closely examined to exclude the possibility of malignant transformation.

Histologic grading and prognostic biomarkers in salivary gland carcinomas

Both the variety and rarity of salivary gland carcinomas pose challenge for using histologic grade and biomarkers to predict outcome. Mucoepidermoid carcinoma is the histologic subtype for which grading is most prognostically and therapeutically relevant. This tumor is graded using standard schemes in a 3-tier manner with the intermediate-grade category shows the most variability between grading systems and thus the most controversy in management. The t(11;19)(q21; p13) MECT1-MAML2 translocation may be an objective marker that can help to further stratify difficult cases. Adenoid cystic carcinomas are graded based on pattern with solid areas correlating with a worse prognosis. Occasionally, adenoid cystic carcinomas may undergo transformation to highly aggressive pleomorphic high-grade carcinomas with frequent nodal metastases. Comparative genomic hybridization has revealed several chromosomal regions (such as 1p32-p36, 6q23-q27) of prognostic interest in adenoid cystic carcinoma. Carcinoma ex-pleomorphic adenoma is actually a category of tumors rather than a single tumor type with both aggressive and indolent versions. These tumors should be further qualified as to type/grade of carcinoma and extent, as intracapsular and minimally invasive tumors behave favorably. Acinic cell carcinomas, although generally considered low grade, can recur, metastasize, or even prove lethal in a significant number of cases suggesting amenability to a grading scheme to separate these biologic groups. Although aggressive histologic parameters (anaplasia, necrosis, and mitoses) are predictive of poor outcome, a standard grading scheme does not yet exists. Acinic cell carcinomas can also undergo high-grade transformation.

Prognostic factors of recurrence in salivary carcinoma ex pleomorphic adenoma, with emphasis on the carcinoma histologic subtype: a clinicopathologic study of 43 cases

Carcinoma ex pleomorphic adenoma is a rare salivary gland neoplasm, especially when the malignant component is only intracapsular/minimally invasive. Moreover, only few studies have assessed the behavior of carcinoma ex pleomorphic adenoma according to the histologic subtype. Forty-three cases of carcinoma ex pleomorphic adenoma were identified over a 27-year period and subjected to a detailed histopathologic analysis. There were 13 intracapsular/minimally invasive and 30 widely invasive carcinomas. There were 15 myoepithelial carcinomas, 25 salivary duct carcinomas, 2 adenocarcinomas not otherwise specified, and 1 carcinosarcoma. There was a trend toward a higher frequency of myoepithelial carcinomas in widely invasive tumors (13/30, 43%) than in intracapsular/minimally invasive (2/13, 15%) carcinoma ex pleomorphic adenoma (P = .095). Adequate follow-up was available for 38 patients. Vascular invasion and distant metastases correlated with decreased disease-free survival and disease-specific survival (P < .05), whereas the extent of invasion and the presence of a high mitotic rate or atypical mitoses correlated with decreased disease-free survival only (P < .05). There was a trend toward worse disease-free survival and disease-specific survival in patients with myoepithelial carcinoma (P = .08). Within the intracapsular/minimally invasive carcinoma ex pleomorphic adenoma group, both myoepithelial carcinoma (2/2, 100%) had metastatic disease, whereas only 1 of 11 nonmyoepithelial carcinoma relapsed (P = .038). Vascular invasion, high mitotic rate, and histologic subtype were found to correlate with recurrence in carcinoma ex pleomorphic adenoma. Patients with intracapsular/minimally invasive tumor have a more favorable outcome than patients with widely invasive neoplasm, but intracapsular/minimally invasive carcinoma ex pleomorphic adenoma can recur and cause death. The presence of myoepithelial carcinoma subtype increases the risk of recurrence in carcinoma ex pleomorphic adenoma, especially within the group of intracapsular/minimally invasive tumors.

Carcinoma ex pleomorphic adenoma in a minor salivary gland: report of a case

BACKGROUND

Carcinoma ex pleomorphic adenoma is exceedingly rare in minor salivary glands of the oral cavity. We present a case of carcinoma ex pleomorphic adenoma (CEPA) of the buccal mucosa in a 47-year-old Turkish patient. The buccal mass was of a size of 1.5 cm located in the left cheek. Pleomorphic adenoma was the tentative diagnosis.

METHODS

The tumor was removed under local anesthesia. Histopathologic evaluation revealed a preexisting pleomorphic adenoma associated with adenoid tumor component with tubulo-cystic and papillary or pseudopapillary structures; CEPA was diagnosed. Capsular integrity was incomplete with infiltration by islands of metaplastic/dysplastic epithelium.

RESULTS

Secondary surgery of the site was performed. No tumor tissue could be detected in the resection specimen. The patient is free of recurrence since 9 months.

Study of growth factors and receptors in carcinoma ex pleomorphic adenoma

Carcinoma ex pleomorphic adenoma (CXPA) is a rare malignant salivary gland tumor derived from a pre-existing pleomorphic adenoma. It is a good model to study the evolution of carcinogenesis, starting with in situ areas to frankly invasive carcinoma. Growth factors are associated with several biological and neoplastic processes by transmembrane receptors. In order to investigate, by immunohistochemistry, the expression of some growth factors and its receptors [EGF receptor, fibroblast growth factor, fibroblast growth factor receptor 1, fibroblast growth factor receptor 2, hepatocyte growth factor, c-Met, transforming growth factor (TGF) beta1, TGFbetaR-II and insulin-like growth factor receptor 1] in the progression of CXPA, we have used ten cases of CXPA in several degrees of invasion- intracapsular, minimally and frankly invasive carcinoma- with only epithelial component. Slides were qualitatively and semi-quantitatively evaluated according to the percentage of stained tumor cells from 0 to 3 (0 = less than 10%; 1 = 10-25%; 2 = 25-50%; 3 = more than 50% of cells). Malignant epithelial cells starting with in situ areas showed stronger expression than luminal cells of pleomorphic adenoma for all antibodies. Most of the intracapsular, minimally and frankly invasive CXPA presented score 3. However, score 2 was more evident in the frankly invasive one. In small nests of invasive carcinoma, negative cells were observed probably indicating that the proliferative process is replaced by the invasive mechanism. Altogether this data infers that these factors may contribute to cell proliferation during initial phases of the tumor.

Update on selected salivary gland neoplasms

CONTEXT

Malignancies of the salivary gland are uncommon and account for 0.3% of all malignancies. In addition to their rarity, diagnosing these tumors can be challenging given the histologic overlap among various subtypes, their morphologic heterogeneity, and the recent recognition of new entities.

OBJECTIVE

To provide an overview of 4 salivary gland malignancies that we often see in consultation, with a focus on essential diagnostic features and the importance of reporting pertinent diagnostic information to ensure appropriate clinical management.

DATA SOURCES

Review of the literature, supplemented by the personal experience of the authors, which is based on their respective institutional experiences and consultation services.

CONCLUSIONS

When diagnosing carcinoma ex pleomorphic adenoma, pathologists must report several important pieces of information to allow for optimal clinical management. In addition to histologic subtype, the degree of differentiation as well as the degree of invasion, if any, must be reported because all have prognostic relevance. Polymorphous low-grade adenocarcinoma can be a challenging diagnosis on biopsy specimens. Evaluation of the tumor periphery and nuclear features should lead to the correct diagnosis in most cases. Salivary duct carcinoma is an aggressive malignancy characterized by histologic resemblance to breast carcinoma, high-grade cytologic features, and expression of androgen receptor. Benign and malignant myoepithelial neoplasms have a broad morphologic spectrum, and immunohistochemistry is important in reaching the correct diagnosis.

Expression of matrix metalloproteinases MMP-2, MMP-9 and their tissue inhibitors TIMP-1 and TIMP-2 in the epithelium and stroma of salivary gland pleomorphic adenomas

AIMS

The balance between matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) is involved in the morphogenesis of normal salivary gland as well as in the mechanisms of tumour invasion and metastasis. The role of MMPs and TIMPs in pleomorphic adenoma has not been elucidated sufficiently. Our aim was to analyse the mRNA and protein expression of MMP-2, MMP-9, TIMP-1 and TIMP-2 in the epithelium and stroma of pleomorphic adenoma and to evaluate their roles.

METHODS AND RESULTS

In each sample from six patients, cells from the epithelium and stroma were obtained by laser microdissection. The mRNA expression of MMPs and TIMPs was determined by real-time quantitative reverse transcriptase-polymerase chain reaction and protein expression was confirmed by immunohistochemistry. Results showed that mRNA expression of MMPs and TIMPs was significantly higher in stroma than in epithelium in most patients. MMPs and TIMPs were immunoreactive mainly in epithelium rather than in stroma.

CONCLUSIONS

Our results provide preliminary evidence that stromal myoepithelium may be the primary source of MMPs and that the stroma has the potential to play a more important role than ductal epithelium in biological behaviour of pleomorphic adenomas. These findings seem worthy of further investigation.

Establishment and characterization of pleomorphic adenoma cell systems: an in-vitro demonstration of carcinomas arising secondarily from adenomas in the salivary gland

Background

Among the salivary gland carcinomas, carcinoma in pleomorphic adenoma has been regarded as a representative carcinoma type which arises secondarily in the background of a pre-existent benign pleomorphic adenoma. It is still poorly understood how and which benign pleomorphic adenoma cells transform into its malignant form, carcinoma ex pleomorphic adenoma.

Methods

We have established five cell systems from a benign pleomorphic adenoma of the parotid gland of a 61-year-old woman. They were characterized by immunofluorescence, classical cytogenetics, p53 gene mutational analysis, fluorescence in-situ hybridization, and histopathological and immunohistochemical examinations of their xenografts, to demonstrate their potency of secondary transformation.

Results

We established and characterized five cell systems (designated as SM-AP1 to SM-AP5) from a benign pleomorphic adenoma of the parotid gland. SM-AP1 to SM-AP3 showed polygonal cell shapes while SM-AP4 and SM-AP5 were spindle-shaped. SM-AP1-3 cells were immunopositive for keratin only, indicating their duct-epithelial or squamous cell differentiation, while SM-AP4/5 cells were positive for both keratin and S-100 protein, indicating their myoepithelial cell differentiation. Chromosome analyses showed numeral abnormalities such as 5n ploidies and various kinds of structural abnormalities, such as deletions, translocations, derivatives and isodicentric chromosomes. Among them, der(9)t(9;13)(p13.3;q12.3) was shared by all five of the cell systems. In addition, they all had a common deletion of the last base G of codon 249 (AGG to AG_) of the p53 gene, which resulted in generation of its nonsense gene product. Transplanted cells in nude mice formed subcutaneous tumors, which had histological features of squamous cell carcinoma with apparent keratinizing tendencies. In addition, they had ductal arrangements or plasmacytoid appearances of tumor cells and myxoid or hyaline stromata, indicating some characteristics of pleomorphic adenoma.

Conclusion

This study demonstrates in vitro that certain cell types from pleomorphic adenoma are able to clone and survive over a long term and develop subcutaneous tumors in nude mice. The histological features of squamous cell carcinoma from the transplanted cell systems in nude mice might suggest a secondary onset of malignancy from a pre-existing benign adenoma.

Immunohistochemical evaluation of androgen receptor, HER-2/neu, and p53 in benign pleomorphic adenomas

CONTEXT

Immunohistochemical stains for androgen receptor (AR), HER-2/neu, and p53 are used as diagnostic markers associated with malignancy in several histologic types of salivary gland tumors. These markers may be useful in differentiating pleomorphic adenoma with cytologic atypia from intracapsular carcinoma ex pleomorphic adenoma (CXPA), as these tumors are often difficult to distinguish on the basis of morphology alone.

OBJECTIVE

To determine whether AR, HER-2/neu, and p53 expression can be seen in entirely benign pleomorphic adenomas.

DESIGN

Androgen receptor, HER-2/neu, and p53 immunoreactivity was assessed in 41 histologically and clinically benign pleomorphic adenomas.

RESULTS

A total of 3 of 41 pleomorphic adenomas exhibited multifocal areas with moderate staining for HER-2/ neu and AR. The positive staining was mainly confined to the epithelial component, where the ductal epithelium showed no cytologic atypia. Immunoreactivity for p53 was observed in the epithelial component of 5 of 41 cases, none of which stained for HER-2/neu and AR. Mean mitotic rate and Ki-67 index were 1 per 10 high-powered fields and 2.7% in HER-2/neu- and AR-positive cases and 1 per 10 high-powered fields and 2.2% in p53-positive cases.

CONCLUSIONS

HER-2/neu, AR, and p53 are expressed in a subset of histologically and clinically benign pleomorphic adenomas. These markers cannot be used to reliably predict early carcinomatous transformation in pleomorphic adenoma.

Peroxiredoxin I, platelet-derived growth factor A, and platelet-derived growth factor receptor alpha are overexpressed in carcinoma ex pleomorphic adenoma: association with malignant transformation

Carcinoma ex pleomorphic adenoma is a rare salivary gland malignancy. It constitutes an important model for the study of carcinogenesis, as it can display the tumor in different stages of progression, from benign pleomorphic adenoma to frankly invasive carcinoma. Growth signaling pathways undergo continuous activation in human tumors, commonly as a consequence of the overexpression of ligands and receptors such as platelet-derived growth factor and platelet-derived growth factor receptor. Hydrogen peroxide is produced after platelet-derived growth factor receptor activation, and it is essential for the sequential phosphorylation cascade that drives cell proliferation and migration. By their ability to degrade hydrogen peroxide, peroxiredoxins are involved in growth factor signaling regulation and in the oxidative stress response. To verify the potential association of peroxiredoxin I, platelet-derived growth factor-A, and platelet-derived growth factor receptor-alpha with carcinoma ex pleomorphic adenoma progression, we investigated the expression of these molecules in carcinoma ex pleomorphic adenoma showing different degrees of invasion. The peroxiredoxin I, platelet-derived growth factor-A, and platelet-derived growth factor receptor-alpha proteins were present in remnant pleomorphic adenoma to only a small extent, but, collectively, they were highly expressed as soon as the malignant phenotype was achieved and remained at elevated concentrations during progression to the advanced stages of carcinoma ex pleomorphic adenoma. In addition, their locations overlapped significantly, strengthening their connection to this growth-signaling pathway. Our results indicate that carcinoma ex pleomorphic adenoma cells acquire at least 2 significant advantages relative to their normal counterparts: resistance to oxidative stress-induced apoptosis, conferred by high peroxiredoxin I concentrations, and sustained growth, reflecting platelet-derived growth factor-A and platelet-derived growth factor receptor-alpha overexpression.