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

A case of giant sarcomatoid carcinoma ex-pleomorphic adenoma of the parotid gland

Carcinoma ex pleomorphic adenoma is a rare malignant parotid neoplasm arising from primary or recurrent benign pleomorphic adenoma. Histologically, it can be sub-classified by upwards of eight different variations (e.g., myoepithelial carcinoma, salivary duct carcinoma, adenoid cystic carcinoma sarcomatoid carcinoma). We present the fourth case in the literature of sarcomatoid carcinoma arising from an underlying pleomorphic adenoma of the parotid gland. We present a case of a 47-year-old female who consulted for a left parotid mass of 15cm long axis. There was no facial paralysis. Fine needle aspiration cytology smears showed a pleomorphic adenoma. The parotid MRI showed a left parotid mass, with heterogeneous signal (hyposignal T1 and hypersignal T2 and in diffusion sequences). The patient underwent a total parotidectomy with a pleomorphic adenoma on extemporaneous examination. Histological examination of the part revealed a pleomorphic adenoma on which a sarcomatoid carcinoma developed. Therefore, a second operation occurred. We performed selective lymph node dissection carrying out the sectors I, II and III followed by radiotherapy. The evolution was favorable. In addition to its rarity, our case joins historical cases by its huge size.

Estrogen Receptor, Progesterone Receptor, and HER-2 Expression in Recurrent Pleomorphic Adenoma

Pleomorphic adenoma (PA) is the most common salivary gland neoplasm and, although mostly benign, recurrences, being called recurrent pleomorphic adenoma (RPA) and malignant transformation to carcinoma ex pleomorphic adenoma (CXPA), do occur. Recently, attention has been focused on molecular targeted cancer therapy in various tumors, including salivary gland tumors. The aim of this study was to investigate the role of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER-2) in PA, RPA, and CXPA. In total, 20 cases of PA, 18 of RPA, and 7 cases of CXPA were immunohistochemically studied for ER, PR, and HER-2. For evaluation of ER and PR, only nuclear expression and greater than 10% positive cells were regarded as cutoff criteria. HER-2 was evaluated semiquantitatively and graded from 0 to 3+. HER-2 amplification was assessed by chromogenic in situ hybridization (CISH). Tumors were negative for ER, PR, and HER-2 in all cases of PA and RPA. A case of CXPA showed moderate and complete membranous staining, and 6 cases were negative. HER-2 amplification was not observed in any case. In conclusion, the lack of ER, PR, and HER-2 expression in PA, RPA, and CXPA suggests that these proteins are not involved in progression, recurrence, or malignant transformation of PA.

Fatty acid synthase and Ki-67 immunoexpression can be useful for the identification of malignant component in carcinoma ex-pleomorphic adenoma

BACKGROUND

Fatty acid synthase (FASN) is the key molecule for catalyzing fatty acid synthesis and have been associated with several malignant tumors.

METHODS

We analyzed the expression of FASN and Ki-67, by immunohistochemistry on 29 carcinomas ex-pleomorphic adenoma (CXPAs) and 25 pleomorphic adenomas (PAs).

RESULTS

Ki-67 proliferation index and FASN expression were significantly higher in patients with CXPA than patients with PA (P < 0.001). We found intense immunoreactivity for FASN in the malignant component of CXPAs, and these malignant areas also had intense nuclear immunoreactivity for Ki-67.

CONCLUSIONS

The present results suggest that overexpression of FASN in CXPAs might be associated with malignant transformation of ductal epithelial cells and/or myoepithelial cells from PA. FASN associated with Ki-67 may be useful diagnostic markers for CXPA.

Particular aspects in the cytogenetics and molecular biology of salivary gland tumours - current review of reports

Salivary gland tumours are a group of lesions whose heterogeneity of biological and pathological features is widely reflected in the molecular aspect. This is demonstrated by an increasing number of studies in the field of genetics of these tumours.

The aim of this study was to collect the most significant scientific reports on the cytogenetic and molecular data concerning these tumours, which might facilitate the identification of potential biomarkers and therapeutic targets. The analysis covered 71 papers included in the PubMed database. We focused on the most common tumours, such as pleomorphic adenoma, Warthin tumour, mucoepidermoid carcinoma, and others. The aim of this study is to present current knowledge about widely explored genotypic alterations (such as PLAG1 gene in pleomorphic adenoma or MECT1 gene in mucoepidermoid carcinoma), and also about rare markers, like Mena or SOX10 protein, which might also be associated with tumourigenesis and carcinogenesis of these tumours.

A low percentage of HER-2 amplification whereas indicates poor prognosis in salivary carcinoma ex pleomorphic adenoma: a study of 140 cases

BACKGROUND

Human epidermal growth factor receptor 2 (HER-2) has been found in many malignant tumours including salivary malignancy. HER-2-targeted therapy has been applied in the treatment of HER-2-overexpressing carcinoma. The aim of this study was to determine the status of HER-2 in salivary invasive carcinoma ex pleomorphic adenoma (ICXPA) in a relatively large Chinese sample, which may provide HER-2-targeted therapy with profound support in the future.

METHODS AND RESULTS

We collected 140 ICXPAs and their related clinicopathological and follow-up data. All cases were examined for HER-2 expression by immunohistochemistry and gene amplification by fluorescence in situ hybridization, if necessary. The study showed that the ratio of HER-2 positivity was only 25% (35/140) in all cases, but the positive ratio in ICXPAs with luminal differentiation for malignant component (32/79, 40.5%) was much higher than that in cases with non-luminal differentiation (3/61, 4.9%). The overexpression of HER-2 was closely associated with gender, histological grade and N stage. HER-2-positive tumours conferred short overall survival time (P = 0.036) and short disease-specific survival time (P = 0.042) in patients, but HER-2 status was not an independent predictor of prognosis.

CONCLUSIONS

Human epidermal growth factor receptor 2 amplification is significantly associated with cell differentiation of the malignant component in ICXPA and it implies an unfavourable prognosis. Although HER-2 positivity is not common in the tumour, HER-2-targeted therapy for those HER-2-positive patients is still worth expecting.

Cellular Proliferation Index between Carcinoma Ex-Pleomorphic Adenoma and Pleomorphic Adenoma

<p>Carcinoma ex pleomorphic adenoma (CXPA) has been considered an interesting model of carcinogenesis, presenting various histological subtypes and invasiveness phase. The objective was to determine the proliferative index of CXPA and comparing to pleomorphic adenoma (PA). Thirty six cases of CXPA (36 PA) and 22 areas of PA in CXPA (residual PA) were studied by Ki-67 expression. All CXPA cases were classified according to invasiveness phase (intracapsular, minimally and frankly invasive) and histopathological subtypes. Data was statistically analyzed by Wilcoxon, Mann-Whitney and Kruskal-Wallis tests. CXPA included 5 intracapsular, 9 minimally invasive and 22 frankly invasive cases. Fifteen cases corresponded to salivary duct carcinoma, 7 to adenocarcinoma NOS, 7 myoepithelial, 5 epithelial-myoepithelial, one case of squamous cell and one case of sarcomatoid carcinoma. The Ki-67 index of PA and residual PA were significantly lower than CXPA. Intracapsular and minimally invasive showed smaller proliferative index than frankly invasive. Considering the subtypes of CXPA, there was not a statistic difference among them. Ki-67 is a useful marker in the differential diagnosis of PA and CXPA, even when in the early invasive phase.</p>

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.

XIAP and Ki-67: A Correlation Between Antiapoptotic and Proliferative Marker Expression in Benign and Malignant Tumours of Salivary Gland: An Immunohistochemical Study

BACKGROUND

Impaired balance between cell proliferation and apoptosis is crucial to the development of malignant neoplasm. The purpose of this study was to evaluate and compare the expression of X-Linked inhibitor of apoptotic protein (XIAP) (antiapoptotic marker) and Ki-67 (proliferative marker) expression in benign and malignant salivary gland (SG) tumours.

MATERIALS AND METHODS

The study consisted of 40 cases of benign SG tumours and 50 cases of malignant SG tumours. The immunohistochemistry was carried out by using Ki-67 antibody (clone MIB-1) and XIAP antibody in all the groups.

RESULTS

XIAP expression was significantly higher in malignant SG tumours than benign SG tumours (p = 0.016). Ki-67 LI was significantly higher in malignant SG tumours than benign SG tumours (p = 0.0002). Statistically significant positive correlation between Ki-67 count and XIAP expression was noted in benign and malignant SG tumours (p = 0.000).

CONCLUSION

As the expression of an antiapoptotic marker (XIAP) increases, the expression of a proliferative marker (Ki-67) also increases from benign to malignant SG tumours. Thus, targeted therapy of XIAP may play a future role in the management of SG malignancy.

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.

Expression of β-catenin and cyclin D1 in Merkel cell carcinomas of the head and neck

BACKGROUND

Merkel cell carcinomas (MCC) are very aggressive tumors of the sun-exposed skin with a high potential to metastasize. Little is known about the genesis of MCC and very few prognostic markers have been detected so far. The Wnt pathway protein β-catenin and the cell cycle protein cyclin D1 are two promotors of tumor growth and are expressed in a variety of malignant neoplasms such as lymphomas, thyroid, breast cancer, and many others.

PATIENTS AND METHODS

Tissue samples of 27 patients with MCC were immunohistochemically stained for β-catenin and cyclin D1 and correlated with overall survival of patients. In addition, western blot analysis was carried out in the two MCC cell lines MCC-13 and MCC-26.

RESULTS

β-catenin showed a cytoplasmatic expression of 10-30 % in 11 samples and an expression lower than 10 % in eight samples. Nuclear staining was visible in two samples. None of the 27 samples expressed cyclin D1.

CONCLUSION

Neither cyclin D1 nor β-catenin was expressed in a statistically significant manner, concluding that the development of MCCs is independent of β-catenin and cyclin D1 expression and these proteins are not suitable as prognostic markers. We could describe the expression pattern of cyclin D1 for the first time.

Metastasizing pleomorphic adenoma: a fascinating enigma

Among salivary gland neoplasms, metastasizing pleomorphic adenoma (MPA) constitutes an extremely rare group of tumors. The present paper reports a case of pleomorphic adenoma (PA) in submandibular gland that, after more than 30 years of initial treatment, recurred and metastasized to ipsilateral neck lymph nodes and parotid gland. In an attempt to elucidate the malignant behavior of metastasizing pleomorphic adenoma, we performed Ki-67, p53, p16, and bcl-2 immunohistochemistry staining of our case sample. Many immunohistochemistry staining studies have been done on malignant salivary gland tumors. However, to the best of our knowledge no immunohistochemistry staining of the aforementioned markers has been previously performed on metastasizing pleomorphic adenoma.

HER-2/neu gene amplification in carcinoma ex pleomorphic adenoma in relation to progression and prognosis: a chromogenic in-situ hybridization study

AIMS

  The aim of this study was to investigate the potential role of HER-2/neu in the stepwise progression of carcinoma ex pleomorphic adenoma (CXPA) and to evaluate its prognostic significance in CXPA.

METHODS AND RESULTS

  We examined HER2 overexpression and HER2 amplification by immunohistochemistry and chromogenic in-situ hybridization in 31 cases of CXPA with ductal differentiation (eight intraductal, five intracapsular, and 18 extracapsular) and seven cases of atypical pleomorphic adenoma (PA). HER2 overexpression and HER2 amplification were found in 17 (54.8%) and 12 (38.7%) of the 31 CXPA cases, respectively. HER2 amplification was more prevalent in extracapsular CXPAs (9/18 cases; 50%) than intracapsular CXPAs (1/5 cases; 20%), intraductal CXPAs (2/8 cases; 25%), or atypical PAs (0/7 case; 0%). The status of HER2 amplification was essentially retained from the intraductal to the extracapsular component in individual extracapsular CXPAs. In addition, HER2 amplification was significantly associated with a worse prognosis (shorter disease-free survival time and shorter overall survival time) among extracapsular CXPAs (each P < 0.05).

CONCLUSIONS

  These results suggest that HER2 may play an important role in the progression of CXPA, and that HER2 amplification may be an additional prognostic indicator of CXPA.

DNA aneuploidy as a topographic malignant transformation pattern in a pleomorphic adenoma of long-term evolution: a case report

Introduction

We present a case of long-term evolution of a submandibular pleomorphic adenoma. There is little information about topographic malignant transformation patterns of pleomorphic adenomas.

Case presentation

We extensively analyze a giant submandibular mixed tumor of 25-year evolution in a 57-year-old Caucasian woman. Deoxyribonucleic acid ploidy was evaluated in different superficial and deep areas using flow cytometry analysis and correlated with pathological and immunohistochemical characteristics. Superficial areas exhibited a typical histological pleomorphic adenoma pattern and were deoxyribonucleic acid diploid. Deep samples showed deoxyribonucleic acid aneuploidy, atypical histological benign features and expression of markers involved at an early-stage of malignant transformation, such as tumor protein 53 and antigen Ki67.

Conclusion

These findings revealed that deep tumor compartments may be involved in the initial stages of malignant transformation. Deoxyribonucleic acid ploidy analysis may provide an additional diagnosis tool and indicate 'uncertain' areas that require careful study to avoid diagnostic errors. Larger studies are needed to confirm our results and to evaluate the usefulness of the technique.

P53 mutation is a rare event in Merkel cell carcinoma of the head and neck

The aim of this retrospective analysis was to evaluate the status of p53 and possible mutations in Merkel cell carcinoma (MCC) cell lines and MCC tissue samples. The p53 mutations are common in different cancer origins but rare in MCCs detected so far. MCCs are highly aggressive neuroendocrine tumors with an enhanced potential to metastasize. Until now, less is known about MCC and new approaches to understand this disease are necessary. RNA and DNA were extracted from two MCC cell lines and 27 archival paraffin-embedded patient samples. After reverse transcription, a real-time PCR and a high-resolution melt analysis were carried out. In both MCC cell lines, we could detect a p53 missense mutation at codon 193 (exon 6) with a change in amino acids (His → Leu). This mutation was equal in both cell lines and was investigated in 27 tissue samples in succession to detect possible accounts for the aggressive behavior of MCCs. Unfortunately, no corresponding p53 mutation could be observed in the investigated tissue samples. A new p53 mutation was detected in MCC cell lines. This mutation could not be determined in patients' samples. Therefore, the aggressiveness of MCC seems to be independent of p53 mutations and other mutations might be responsible for developing MCC.

Study of histopathological, morphological and immunohistochemical features of recurrent pleomorphic adenoma: an attempt to predict recurrence of pleomorphic adenoma

BACKGROUND

Recurrent pleomorphic adenoma (RPA) is an uncommon and challenging disease. The aim of this study was to review the clinical information obtained by examining RPA patients, to determine its histomorphological features and to verify the expression of the Mcm-2 markers of cell proliferation and the expression of p-53 in pleomorphic adenoma (PA), RPA, and RPA with malignant transformation (TRPA).

METHODS

A total of 10 cases of PA and 29 cases of RPA were examined in detail for the presence of nodules and their histomorphological features. Cell proliferation and expression of p-53 were detected by the immunohistochemical technique using the antibodies against Mcm-2 and p-53.

RESULTS

Histopathologically, RPA is very similar to PA; the only difference found was that all the cases of RPA were multinodular. When comparing primary and recurrent tumor, no significant difference was found in terms of cell proliferation and the expression of p-53; however, in the RPA with areas of malignant transformation there was an increased expression of these proteins.

CONCLUSION

This study showed that recurrences were multinodular, with nodules varying in numbers and sizes. No significant difference in histological features was found between RPA and PA. Moreover, the immunohistochemical study showed a low expression of p-53 and Mcm-2 in PA and RPA and an increased expression of these proteins in the RPA with areas of malignant transformation.

Transformation of pleomorphic adenoma to carcinoma ex pleomorphic adenoma of the parotid gland is independent of p53 mutations

BACKGROUND AND OBJECTIVES

This retrospective study was performed to evaluate the status of p53 in pleomorphic adenomas and carcinomas ex pleomorphic adenoma in the parotid gland. As loss or mutation of p53 can cause malignant transformation, the possible degeneration of pleomorphic adenomas to carcinomas ex pleomorhic adenoma was investigated by mutational analysis.

METHODS

Twenty-five Patients including 14 patients with pleomorphic adenomas and 11 patients with carcinoma ex pleomorphic adenoma of the parotid gland were examined for p53 status. DNA was extracted out of paraffin-embedded tissue and PCR was performed for the coding exons 2-11. Denaturing gradient gel electrophoresis (DGGE) was carried out for mutational analysis and DNA sequencing was performed in case of a suspected mutation.

RESULTS

Fourteen pleomorphic adenomas and 11 carcinomas ex pleomorphic adenoma were screened for p53 status and potent mutations. Subsequent sequencing of the distinct exons showed no mutation.

CONCLUSION

We could not detect mutations of p53 neither in benign nor malignant parotid tumors and we therefore assume that p53 plays no role in the transformation from pleomorphic adenoma to carcinoma ex pleomorphic adenoma.

Expressions of androgen receptor and its co-regulators in carcinoma ex pleomorphic adenoma of salivary gland

AIMS

Androgen receptor (AR) signalling is involved in cancer progression. The expression of AR has been reported in carcinoma ex pleomorphic adenoma (CXPA) of salivary gland, however AR gene status and the expressions of cofactors for AR signalling have not been investigated. The aims of this study were to investigate the expressions of each of the molecules that contribute to AR activation with or without ligands in CXPA. In addition, AR gene amplification and single-nucleotide polymorphism were investigated.

METHODS

Ten cases of CXPA and 23 cases of pleomorphic adenomas (PA) of the salivary glands were immunostained for the AR co-regulators (SRC1, p300, and NCoR1) and the signalling molecules involved in the ligand-independent pathway (i.e., HER-2/neu and STAT3). AR gene amplification and single-nucleotide polymorphism were investigated by dual-coloured fluorescent in situ hybridisation and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), respectively.

RESULTS

AR expression was observed in nine of 10 cases of CXPA and in 30.4% of PA cases, a statistically significant difference. The expression, with low or high intensity, of HER-2/neu and STAT3 was more frequent in CXPA (6/10 and 9/10, respectively) than in PA (0% and 46.7%). The expression of co-activators was also stronger, though only slightly, in CXPA than in PA. The gain of chromosome X and AR gene amplification were not observed in any CXPA or PA cases, and the G --> A allele in codon 211 was detected in only one case (a CXPA).

CONCLUSIONS

These results suggest that although AR may be activated in the pathway with or without ligands, the expression of co-regulators and AR gene aberrations are not involved in the carcinogenesis of CXPA.

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.

[Carcinoma ex pleomorphic adenoma of major salivary glands--a clinicopathologic review]

BACKGROUND

Pleomorphic adenoma (PA) is the most common neoplasm of the major salivary glands. There are three subtypes of malignant PA: carcinoma ex pleomorphic adenoma (CXPA); carcinosarcoma (true malignant mixed tumor) and metastasizing pleomorphic adenoma. The most common subtype of malignant PA is CXPA which develops in primary or recurrent PA. For proper diagnosis of CXPA, a statement of coexistence of pleomorphic adenoma and carcinoma (or carcinoma after prior PA surgery) is needed. Own material is presented because of rarity and clinicopathologic specificity of this neoplasm.

METHODS

Retrospective analysis of the medical data of 19 patients who were treated at our department because of CXPA from 1990 to 2002 was done. The following clinical factors were evaluated: age, sex, symptoms (time of lasting, evolution), tumor size, invasion of the adjacent structures and facial nerve, neck nodes, clinical stage, treatment outcome. One pathologist reviewed histological material of 18 out of 19 patients who had been operated and pathological factors such as sensitivity and accuracy of fine needle aspiration biopsy, grade, histology and proportion of malignant component in tumor, lymph nodes metastases were analyzed.

RESULTS

There were 11 men and 8 women, the mean age was 57 years. In 15 cases, tumor was localized in the parotid and in 4 in the submandibular gland. Two patients had history of prior surgery of PA. Duration of symptoms of benign PA was from 2 to 40 years (mean 17.8 years). Symptoms of malignant transformation occurred in 15 patients, the most common were rapid enlargement of tumor, pain and facial nerve palsy. Tumor size varied from 2 to 20 cm with a mean of 6 cm. In 14 patients, the neck was evaluated clinically as No, in 5, examination identified enlarged lymph nodes. Adjacent structures were invaded by neoplasm in 5 cases. Sensitivity and accuracy of fine needle aspiration biopsy in detection of malignant character of PA were 60% and 46% respectively. 17 out of 18 tumors reviewed by the pathologist were high grade. Only in 6 patients, proportion of carcinoma in the mass was less than 50%. The most common malignant component in CXPA was adenocarcinoma (9 cases) and undifferentiated carcinoma (6 cases). Pathologic examination showed metastases to the lymph nodes in 7 out of 10 patients with prior neck dissection. 16 patients were treated surgically (12 of them had also radiation therapy) and 3 patients underwent only (chemo)radiotherapy. Determinate survival at 5 years was 73.6% and in the group treated surgically (alone or with postoperative irradiation) 87.5%.

CONCLUSIONS

Malignant transformation of PA occurs in 5 to 25% untreated patients, usually after 15-20 years and warning symptoms are present in the most cases. Fine needle aspiration biopsy has insufficient sensibility and accuracy in detection of malignant character of PA. Clinical picture and histopathological examination determinate the diagnosis of CXPA. Proper histological classification of malignant component can be found difficult. Surgical treatment (alone or with postoperative irradiation), if possible, allows to achieve good locoregional control of CXPA. 5-years survival varied between 30 to 76%. The best method of prevention and treatment of CXPA is early and radical removal of all major salivary glands tumors.

Apocrine Mixed Tumors of the Skin With Architectural and/or Cytologic Atypia: A Retrospective Clinicopathologic Study of 18 Cases

We present a series of 18 atypical apocrine mixed tumors of the skin characterized by architectural and/or cytologic atypia but which nevertheless do not qualify these lesions as carcinomas. There were 15 males and 3 females, and all but 1 presented with solitary nodules ranging in size from 4 to 20 mm; 1 female had a large tumor of 12 cm. The tumors were preferentially located on the head area, especially the face (13 cases). Other locations included the lower extremities (3) and inguinal area (2). In all patients, surgical excision of the tumors was performed. Clinical follow-up was available in 11 cases and ranged from 1 to 24 years (mean 9.6 y; median 5 y). No recurrences or metastases were documented. Overall, the lesions manifested a rather benign architecture, usually with good circumscription, lack of capsular breach or hypercellularity; however, some asymmetry, focally irregular infiltrationlike or pushing tumorous borders were seen. Microscopically, 17 cases conformed to the so-called hyaline cell-rich variant and showed multinucleated, bizarre, hyperchromatic cells in hyaline cell areas that had a myoepithelial immunophenotype; in 1 case, atypical mitotic figures were noted. One case showed mild nuclear pleomorphism in the ductal component. Tumors were negative for p53, including bizarre giant cells that did not label with Ki-67. Ultrastructurally, hyaline cells exhibited features consistent with myoepithelial differentiation. Seven cases studied by immunohistochemistry proved negative for HER-2/neu (c-erbB-2) protein expression, and the HER-2/neu gene was not amplified by fluorescence in situ hybridization analysis in 5 cases tested. As controls, 4 authentic malignant mixed tumors were studied, but these likewise tested negative for HER-2/neu protein expression and showed no gene amplification; 1 malignant mixed tumor had polysomy 17. We conclude that some atypical cytoarchitectural features in apocrine mixed tumors, albeit worrisome, do not indicate a malignant change.

Advances in salivary gland pathology

This review summarizes the new findings on salivary gland pathology under the following categories: immunohistochemistry; molecular genetics; newly recognized tumour types; known tumour entities with new findings; and progression of salivary gland tumours. In the application of immunohistochemistry, CD117 can aid in highlighting the luminal cell component of various salivary gland tumours, whereas p63 or maspin can aid in highlighting the abluminal cell component. A high Ki67 index remains the most useful marker to predict adverse outcome in salivary gland carcinoma. Specific chromosomal translocations are recognized in pleomorphic adenoma (with translocation involving PLGA1 or HMGA2 gene) and mucoepidermoid carcinoma (with MECT1-MAML2 gene fusion). Newly recognized entities include: sclerosing polycystic adenosis (with recent molecular evidence supporting its neoplastic nature), sclerosing mucoepidermoid carcinoma with eosinophilia, keratocystoma, adenoma with additional stromal component (lymphadenoma, lipoadenoma and adenofibroma), cribriform adenocarcinoma of the tongue and signet ring adenocarcinoma of minor salivary gland. Known tumour entities with new findings include: salivary duct carcinoma (with newly recognized mucinous, micropapillary and sarcomatoid variants), intraductal carcinoma (with controversies in terminology), mucoepidermoid carcinoma (with newly proposed grading parameters and oncocytic variant), epithelial-myoepithelial carcinoma (with newly recognized morphological variants), small cell carcinoma (with most cases being related to Merkel cell carcinoma), extranodal marginal zone B-cell lymphoma (with specific chromosomal translocation) and chronic sclerosing sialadenitis (being a component of IgG4-related sclerosing disease). Progression of salivary gland tumours can take the form of malignant transformation of a benign tumour, progression from low-grade to high-grade carcinoma, dedifferentiation, or stromal invasion of an in situ carcinoma.

Carcinoma ex pleomorphic adenoma of the salivary gland: an immunohistochemical study

The proliferative activity of the tumor cells and the expression of tumor-associated genes and sex steroid hormone receptors were investigated immunohistochemically in ten cases of carcinoma ex pleomorphic adenoma (Ca-ex-PA) of the salivary glands. These were analyzed in benign and malignant components separately, and then were compared with ten cases of the other malignant tumors [adenocarcinomas, not otherwise specified (ACN) and salivary duct carcinomas (SDC)] and ten cases of pleomorphic adenomas (PA). The results obtained in this study were as follows: (1) malignant component of Ca-ex-PA showed a higher incidence of PCNA and Ki67 than benign component of Ca-ex-PA. A significant difference between benign component of Ca-ex-PA and PA was not observed. (2) A significant difference in the incidence of p53, c-erbB-2, EGFR overexpression was observed only between malignant component of Ca-ex-PA and benign component of Ca-ex-PA. (3) The incidence of PCNA, Ki67, p53, c-erbB-2 overexpression in malignant component of Ca-ex-PA showed the highest data among the four groups. These results suggest that Ca-ex-PA acquired the particular biological behavior in contrast to the other salivary neoplasms in the long-standing process while PA undergoes malignant transformation.