Detection of antibody subclasses IgA, IgM and IgG against HPV L1 in HPV-positive oropharyngeal squamous cell carcinoma patients: a pilot study.

PURPOSE: Despite prognostic superiority of HPV-positive oropharyngeal squamous cell carcinoma (OPSCC), up to 25% of patients will suffer from recurrence within the first 5 years. Therefore, it is of great scientific interest to find relevant biomarkers to identify patients at risk. In this prospective observational study, we aimed to investigate the dynamics of HPV-L1 capsid protein specific antibody (AB) subclasses IgA, IgM, and IgG in HPV-positive OPSCC patients under therapy. METHODS: Serum samples from HPV-positive OPSCC patients, identified by positive p16-immunohistochemistry, were collected before and during tumor-specific therapy and 3-6 months during follow-up. They were analyzed for the presence of HPV-L1 AB subclasses IgA, IgM, and IgG using an HPV-L1-specific immuno-assay. Additionally, a PCR-based HPV-DNA detection from the tumor tissue was performed. RESULTS: Altogether, 33 patients with a mean follow-up of 55 months were included. Analysis of a total of 226 serum samples revealed that the most common L1-AB-subclass pattern was characterized by IgG > > IgA > IgM without significant fluctuation during the course of disease. Patients with excessive IgG levels tended to higher tumor stages and three out of three patients with disease recurrence showed increasing IgG AB titers beforehand. Seven patients showed an IgA dominance at diagnosis, which was associated with a better disease-free survival. CONCLUSION: Despite limited cases, our prospective pilot study revealed promising trends in HPV L1 AB subclasses and may contribute useful information for future risk stratification and post-treatment monitoring in HPV-positive OPSCC patients.

Endoscopic trans-sphenoidal pituitary surgery does not impact postoperative nasal quality of life.

PURPOSE: The aim of this prospective longitudinal study was to assess both subjective quality of life using questionnaires and objective examination of nasal function with regard to olfaction, nasal air flow and mucociliary clearance in patients after minimally invasive, turbinate-preserving endoscopic transnasal trans-sphenoidal pituitary surgery. METHODS: Patients undergoing endoscopic transnasal pituitary surgery were recruited prospectively and examined during three study visits, preoperatively and 3 and 6 months postoperatively. We examined nasal function using sniffin' sticks test, rhinomanometry, saccharin transit time test, and endoscopic and radiological scores. In addition, the influence on subjective quality of life and mental health was recorded using the Sinonasal-Outcome-Test-20 (SNOT-20) and the Hospital-Anxiety-and-Depression-Scale (HADS). RESULTS: 20 patients undergoing endoscopic pituitary tumor resections were included. No significant changes in olfaction or mucociliary clearance were noted. Nasal air flow showed a tendency to increase in the postoperative course lacking significance. Both the endoscopy and the radiological scores showed a significant deterioration, especially after 3 months, with a trend towards improvement over time. However, neither the SNOT-20 nor the HADS showed significant changes compared to baseline. CONCLUSIONS: Our concept of minimally invasive endoscopic tumor resections on the pituitary gland with preservation of nasal turbinates shows low morbidity for the patient. Despite objectifiable surgery-associated changes in the nose, nasal physiology in terms of smell, airflow and mucociliary clearance can be preserved and the subjective quality of life of our patients remains stable.

6-shogaol induces apoptosis and enhances radiosensitivity in head and neck squamous cell carcinoma cell lines.

Ginger (Zingiber officinale Roscoe) is used for a wide array of conditions in traditional medicine in Asia, but little is known about the effect on head and neck cancer. In this study, the effect of two major pharmacologically active compounds of ginger, 6-gingerol and 6-shogaol, were studied on head and neck cancer cell lines. Furthermore, experiments in combination with established treatment methods for head and neck cancer were performed. Proliferation assays showed a dose-dependent reduction of cell viability. Flow cytometry analysis revealed the induction of apoptosis. Western blot analysis indicated that the antiapoptotic protein survivin was suppressed after treatment. Although a combination of 6-shogaol with cisplatin exhibited no synergistic effect, the combination with irradiation showed a synergistic reduction of clonogenic survival. In conclusion, ginger compounds have many noteworthy effects on head and neck cancer cell lines. In particular, the enhancement of radiosensitivity is remarkable.

Comparative Analysis of Clinical and Pathological Lymph Node Staging Data in Head and Neck Squamous Cell Carcinoma Patients Treated at the General Hospital Vienna.

BACKGROUND: Results from publications evaluating discrepancies between clinical staging data in relation to pathological findings demonstrate that a significant number of head and neck squamous cell carcinoma (HNSCC) patients are not correctly staged. The aim of this retrospective study was to analyze potential discrepancies of radiological assessment versus pathological data of regional lymph node involvement and to compare the results with data published in the literature. PATIENTS AND METHODS: In a retrospective analysis we focused on patients with HNSCC routinely treated by surgery plus postoperative radiotherapy between 2002 and 2012. For inclusion, complete pre-operative clinical staging information with lymph node status and patho-histological information on involved lymph node regions as well as survival outcome data were mandatory. We included 87 patients (UICC stage III-IV 90.8%) for which the aforementioned data obtained by CT or MRI were available. Overall survival rates were estimated by the Kaplan-Meier method. The Pearson correlation coefficient and Spearman's rank correlation coefficient (non-linear relationship) was calculated. RESULTS: Discrepancies at the level of overall tumour stage assessment were noticed in 27.5% of all cases. Thereof, 5.7% were assigned to patho-histological up-staging or down-staging of the primary tumour. At the lymph node level, 11.5% of the patients were downstaged, and 10.3% were upstaged. CONCLUSIONS: The study showed that in approximately one-fifth (21.8%) of the patients, lymph node assessment by CT or MRI differs from the pathologic staging, an outcome that corresponds well with those published by several other groups in this field.

The prognostic significance of ß-catenin, cyclin D1 and PIN1 in minor salivary gland carcinoma: ß-catenin predicts overall survival.

Minor salivary gland carcinoma is a rare and heterogeneous type of cancer. Molecular prognostic and predictive markers are sparse. The aim of this study was to identify new prognostic and predictive markers in minor salivary gland carcinoma. 50 tissue samples of carcinomas of the minor salivary glands (adenoid cystic carcinoma n = 23, mucoepidermoid carcinoma n = 12, adenocarcinoma n = 10, carcinoma ex pleomorphic adenoma n = 2, salivary duct carcinoma n = 1, clear cell carcinoma n = 1, basal cell carcinoma n = 1) were immunohistochemically stained for ß-catenin, cyclin D1 and PIN1. Expression patterns were analyzed and correlated to clinical outcome of 37 patients with complete clinical data. High expression of membranous ß-catenin was linked to significantly better overall survival in patients with adenoid cystic carcinoma (log rank test, χ (2) = 13.3, p = .00397, Bonferroni corrected p = .024). PIN1 and cyclin D1 did not show any significant correlation to patients' clinical outcome. Expression of ß-catenin in adenoid cystic carcinoma of the minor salivary glands significantly correlates with better overall survival. Hence, evaluation of ß-catenin might serve as a clinical prognostic marker.

Oral health status and dental care behaviours of head and neck cancer patients: a cross-sectional study in an Austrian tertiary hospital.

OBJECTIVES: This study aimed to assess the oral health status and dental care behaviours of patients treated for head and neck squamous cell carcinoma (HNSCC) in an Austrian tertiary hospital. MATERIALS AND METHODS: Dental care behaviours, oral hygiene level, caries, and periodontal parameters were assessed in 48 patients treated for HNSCC >6 months ago. RESULTS: Only 52 % requested a dental check-up after HNSCC diagnosis and prior to treatment, and of those, 80 % received some type of dental treatment. At time-point of clinical examination, 69 % of the patients had consulted a dentist within the last year, but 88 % still needed dental treatment; 75 % had at least one tooth with caries and 78 % had moderate to severe periodontitis. CONCLUSION: Although it was recommended, only half of the patients did consult a dentist prior to HNSCC treatment and oral health appeared, in general, low prioritized. CLINICAL RELEVANCE: About 90 % of the current group of head and neck squamous cell carcinoma cancer patients presented large treatment needs, both in regard with caries and periodontal disease, about 20 months after cancer treatment.

Primary radiotherapy or postoperative radiotherapy in patients with head and neck cancer: Comparative analysis of inflammation-based prognostic scoring systems.

INTRODUCTION: Inflammation-based scoring systems have potential value in evaluating the prognosis of cancer patients; however, detailed comparative analyses in well-characterized head and neck cancer patient collectives are missing. METHODS: We analyzed overall survival (OS) in locally advanced head and neck cancer patients who were treated with curative intent by primary radiotherapy (RT) alone, by RT in combination with cetuximab (RIT) or with cisplatin (RCHT), and by primary surgery followed by postoperative radiotherapy (PORT). The primary RT collective (N = 170) was analyzed separately from the surgery plus RT group (N = 148). OS was estimated using the Kaplan-Meyer method. Cox proportional-hazard regression models were applied to compare the risk of death among patients stratified according to risk factors and the inflammation-based Glasgow Prognostic Score (GPS), the modified GPS (mGPS), the neutrophil-lymphocyte ratio (NLR), the platelet-lymphocyte ratio (PLR), and the prognostic index (PI). RESULTS: A prognostic relevance of the scoring systems for OS was observed in the primarily irradiated, but not in the PORT collective. OS was 35.5, 18.8, and 15.4 months, respectively, according to GPS 0, 1, and 2. OS according to mGPS 0-2 was identical. The PLR scoring system was not of prognostic relevance, while OS was 27.3 months in the NLR 0 group and 17.3 months in the NLR 1 group. OS was 35.5 months in PI 0, 16.1 months in PI 1, and 22.6 months in PI 2. CONCLUSION: GPS/mGPS scoring systems are able to discriminate between three risk groups in primarily, but not postoperatively irradiated locally advanced head and neck cancer patients.

Improved survival in HPV/p16-positive oropharyngeal cancer patients treated with postoperative radiotherapy.

INTRODUCTION: In the literature, HPV infection and/or p16 positivity have been consistently demonstrated to correlate with improved response rates in oropharyngeal squamous cell carcinoma (OPSCC) patients treated with primary radiotherapy (RT) alone and in combination with chemotherapy. However, the exact role of HPV/p16 positivity in patients treated with postoperative RT is still unclear. METHODS: We analyzed tumor samples for HPV-DNA and p16 expression and correlated these variables with treatment outcome in a series of 63 consecutively treated oropharyngeal cancer patients (95% stage III/IV). HPV and p16 analysis were performed using validated test systems. Survival was estimated by the Kaplan-Meier method. Cox proportional hazard regression models were applied to compare the risk of death among patients stratified according to risk factors. RESULTS: Expression of p16 or high-risk HPV-DNA was detected in 60.3% and 39.6% of the tumors, respectively. p16 expression [overall survival (OS) at 2 years: 91%] as well as HPV infection (OS at 2 years: 95%) was associated with improved OS. Mean survival in p16-positive patients was 112 months compared to 64.6 months in case of p16 negativity. All HPV-positive tumors stained positive for p16. In a multivariable analysis, p16 positivity was associated with improved OS and with disease-free survival. CONCLUSION: p16 expression and HPV infection are strongly associated with the outcome of postoperatively irradiated OPSCC patients. HPV and p16 double-negative OPSCC patients should be regarded as a distinct "very high-risk patient group" that may benefit from intensified or novel treatment combinations.

Effect of the coffee ingredient cafestol on head and neck squamous cell carcinoma cell lines.

BACKGROUND AND PURPOSE: Cafestol is a diterpene molecule found in coffee beans and has anticarcinogenic properties. The aim of the study was to examine the effects of cafestol in head and neck squamous cell carcinoma (HNSCC) cells. MATERIALS AND METHODS: Three HNSCC cell lines (SCC25, CAL27 and FaDu) were treated with increasing doses of cafestol. Then combination experiments with cisplatin and irradiation were carried out. Drug interactions and possible synergy were calculated using the combination index analysis. Clonogenic assays were performed after irradiation with 2, 4, 6 and 8 Gy, respectively, and the rate of apoptosis was measured with flow cytometry. RESULTS: Treatment of HNSCC cells with cafestol leads to a dose-dependent reduction of cell viability and to induction of apoptosis. Combination with irradiation shows a reduction of clonogenic survival compared to each treatment method alone. In two of the cell lines a significant additive effect was observed. CONCLUSION: Cafestol is a naturally occurring effective compound with growth-inhibiting properties in head and neck cancer cells. Moreover, it leads to a significant inhibition of colony formation.

Assessment of caroverine as a potential chemotherapeutical agent in HNSCC cell lines.

Since the prognosis of head and neck squamous cell carcinoma (HNSCC) still remains poor, identifying novel chemotherapeutic agents is of outmost importance. The anticancer potential of quinoxalines has been described in various tumor entities. Caroverine, also a quinoxaline derivative, has been shown to suppress tumor promotion factors. The aim of this study was to evaluate the effect of caroverine on HNSCC cell lines. The HNSCC cell lines SCC9, SCC25, CAL27, and FaDu were incubated with caroverine alone or in combination with cisplatin, 5-fluorouracil (5-FU) or cetuximab. Cell viability was measured using the CCK-8 assay. The murine 3T3 fibroblast cell line was used to address tissue specificity. Apoptosis was visualized by immunohistochemistry. Caroverine showed a dose-dependent growth inhibition in all cell lines, IC50 values ranged from 75.69 to 179.80 µM. This effect was increased when caroverine was combined with cetuximab or 5-FU. Immunohistochemistry displayed more apoptosis after caroverine treatment compared to controls. Furthermore, caroverine alone had no growth inhibitory effect on 3T3 cells. For the first time, this study provides evidence that caroverine may serve as a supportive drug in the treatment of HNSCC patients.

Significance of p16 expression in head and neck cancer patients treated with radiotherapy and cetuximab.

BACKGROUND: HPV-infection, p16 positivity, and EGFR expression have been correlated with favorable responses of head and neck cancer patients treated with radiotherapy (RT) with or without chemotherapy. However, a possible correlation of HPV/p16 and EGFR status on the effect of RT in combination with cetuximab has not been sufficiently investigated. MATERIALS AND METHODS: We analyzed tumor samples for p16 and EGFR expression and correlated these variables with treatment outcome. Cox-proportional-hazard regression models were applied to compare the risk of death among patients stratified according to risk factors. Survival was estimated by the Kaplan-Meier method. Results were compared with an institutional historical control group treated without cetuximab and with published data. RESULTS: Expression of p16 was predominantly found in oropharyngeal squamous cell cancer patients (OPSCC; 36.6% positivity; 92% of all cases), while EGFR was expressed at high levels in all tumor subsites (82%). p16 expression was associated with improved overall survival in irradiated OPSCC patients (2-year overall survival of 80% in p16-positive vs. 33% overall survival in p16-negative patients). In a multivariable analysis covering all tumor sites, nodal stage (> N2a vs. ≤ N2a) and tumor site (OPSSC vs. non-OPSCC) had an impact on overall survival. CONCLUSION: Our results show that p16 positivity is associated with a favorable outcome in OPSCC patients treated with RT and cetuximab.

Trichoblastic carcinosarcoma of the neck: Case report and molecular analysis of a seldom, relapsing entity and a review of the literature.

Trichoblastic carcinosarcoma is a seldom biphasic adnexal tumor with malignant epithelial and mesenchymal components. The authors report the first tumor on the neck developed from preexistent trichoblastoma showing aggressive, recurrent behavior. An 82-year-old man presented with a solitary 3-cm exophytic lesion. Histology verified the diagnosis of trichoblastic carcinosarcoma. Four years earlier, a trichoblastic carcinoma arising in a preexisting trichoblastoma was excised at the same location. Despite successful surgical treatments, three local recurrences within 4 years were diagnosed. After the second relapse, the patient agreed on adjuvant radiation. Twelve months later, another relapse was excised in toto. In the last surgical specimen, only the mesenchymal component was found. Copy number variation analysis of the preexisting tumor and two recurrences revealed the same entity and additional chromosomal aberrations in the recurrences. Adnexal carcinosarcomas are seldom, yet presumably underdiagnosed biphasic tumors with aggressive growth potential. They should have adequate preoperative clarification with wide tumor excision, as radiosensitivity seems to be of limited effect.

ADAM8 in squamous cell carcinoma of the head and neck: a retrospective study.

BACKGROUND: A disintegrin and metalloproteinase (ADAMs) have been associated with multiple malignancies. ADAMs are involved in cell fusion, cell migration, membrane protein shedding and proteolysis. ADAM8 has been found to be overexpressed in squamous cell carcinomas of the lung. A new study showed that ADAM8 is significantly overexpressed in metastasis of squamous cell carcinomas of the head and neck (HNSCC). METHODS: We determined ADAM8 levels in the serum of 79 HNSCC patients at the time of diagnosis, in 35 patients 3 months after treatment and in 10 patients 1 year after therapy and compared the results to the sera of 31 healthy volunteers. We also constructed tissue microarrays to detect ADAM8 immunohistochemically in 100 patients. The results were correlated with the survival data of the patients to determine the diagnostic and prognostic value. RESULTS: The data demonstrated that patients with high ADAM8 expression in the tumor have worse survival rates. We found that high ADAM8 serum levels correlated with high ADAM8 expression in tumor samples. Soluble ADAM8 levels did not show any prognostic or diagnostic properties. CONCLUSION: In summary ADAM8 expression is a prognostic factor for survival of patients with head and neck squamous cell carcinoma.

HPV infection and p16 expression in carcinomas of the minor salivary glands.

The correlation between p16 upregulation and high-risk HPV infection is well known in head and neck squamous cell cancer. However, no information is available on rare carcinomas of the minor salivary glands. We analyzed 38 samples of minor salivary gland malignancies. p16 expression was determined by immunohistochemistry, HPV DNA by using in situ hybridization to detect low (type 6 and 11) and high (type 16 and 18) risk HPV types. In 71% of samples p16 expression was found. Low-risk HPV DNA could not be detected in any of the samples, whereas high-risk HPV DNA was found in two samples of mucoepidermoid carcinoma, which also showed the highest immunoreactivity with p16. HPV infection does not seem to be a common event in minor salivary gland carcinoma. Upregulation of p16 is present in the majority of cases but only diffuse staining correlates with HPV 16 and 18 infections.

Radiosensitization of head and neck cancer cells by the phytochemical agent sulforaphane.

BACKGROUND AND PURPOSE: Sulforaphane is a naturally occurring compound found in broccoli and other cruciferous vegetables. Recently it gained attention because of its antiproliferative properties in many cancer cell lines. The aim of this study was to investigate whether sulforaphane could act as a radiosensitizer in head and neck squamous cell carcinoma cell lines. MATERIALS AND METHODS: Four head and neck squamous cell carcinoma cell lines (i.e., (HNSCC) SCC9, SCC25, CAL27, and FADU) were treated with sulforaphane and subsequently irradiated. Then proliferation and clonogenic assays were performed. Apoptosis was detected by flow cytometry. Possible regulation of Akt and Mcl-1 was investigated by western blotting. RESULTS: Sulforaphane and radiation in combination leads to stronger inhibition of cell proliferation and of clonogenic survival than each treatment method alone. Western blot analysis of Akt and Mcl-1 showed no changed expression. CONCLUSION: Sulforaphane is a promising agent in the treatment of head and neck cancer due to its antiproliferative and radio-sensitizing properties. A combination of sulforaphane and radiation decreases clonogenic survival. Apoptosis is not regulated through Akt or the Mcl-1 protein.

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.

Sinonasal mucosal melanoma: treatment strategies and survival rates for a rare disease entity : A single center experience and review of literature.

BACKGROUND: Sinonasal mucosal melanoma (SNMM) is a rare disease entity comprising 0.4-1.3% of all melanomas. Surgery with free margins has been the primary treatment over decades. Neither the addition of radiotherapy nor chemotherapy could significantly improve outcome rates of this devastating malignancy. This study presents our clinical experience with SNMM over a 19-year period and summarizes the current body of literature on SNMM. METHODS: This retrospective analysis included 12 patients with SNMM treated from 2001 to 2019 at an academic center. Additionally, a literature review of the last 29 years on treatment and survival data of SNMM was conducted. RESULTS: Main initial symptoms were epistaxis and nasal obstruction. Of the patients 9 underwent endoscopic surgery, 6 received adjuvant therapy. 3 patients who did not undergo surgery, received chemoradiotherapy, radiotherapy alone, and chemotherapy alone, respectively. At the time of diagnosis 2 patients had distant metastases and 4 patients developed distant metastases during the course of the disease. Mean overall survival (OS) was 30.6 months, 3­year and 5­year OS were 25%, and 18.2%, respectively. CONCLUSION: Unspecific symptoms and hidden anatomic locations lead to delayed diagnosis and increased rates of metastatic dissemination. Distant metastasis is the main treatment failure in SNMM. Surgery with free margins remains the primary treatment for SNMM. Adjuvant radiotherapy might improve local control in individual cases but efficient systemic therapy is needed to improve outcome rates. To evaluate and define more effective targeted treatment options and improve outcome rates, homogeneous data and prospective multicentric analysis are needed.

Expression of the tetraspanins CD9, CD37, CD63, and CD151 in Merkel cell carcinoma: strong evidence for a posttranscriptional fine-tuning of CD9 gene expression.

Tetraspanins including CD9, CD37, CD63, and CD151 are linked to cellular adhesion, cell differentiation, migration, carcinogenesis, and tumor progression. The aim of the study was to detect, quantify, and evaluate the prognostic value of these tetraspanins in Merkel cell carcinoma and to study the regulation of CD9 mRNA expression in Merkel cell carcinoma cell lines in detail. Immunohistochemical staining of 28 Merkel cell carcinoma specimens from 25 patients showed a significant correlation of CD9 (P=0.03) and CD151 (P=0.043) expression to overall survival. CD9 and CD63 expression correlated significantly to patients' disease-free interval (P=0.017 and P=0.058). Of primary Merkel cell carcinoma tumors, 42% were CD9 positive in contrast to only 21% of the subcutaneous in-transit metastases. Characterization of the 5' untranslated region (UTR) of the CD9 mRNA from two cultured Merkel cell carcinoma cell lines revealed the presence of two major RNA species differing only in the length of their 5' termini (183 versus 102 nucleotides). In silico analysis of the long CD9 mRNA predicted a 5' UTR folding pattern blocking ribosomal scanning and translation. Quantitative data by real-time RT-PCR not only indicated a reduction of CD9 mRNA but also a distinct quantitative shift toward the long 5' UTR in CD9 receptor negative cells. These observations provide an example for a posttranscriptional fine-tuning of CD9 gene expression in tumor cells.

Betulinic acid a radiosensitizer in head and neck squamous cell carcinoma cell lines.

BACKGROUND AND PURPOSE: Betulinic acid, a pentacyclic triterpene, is a new cytotoxic compound active on melanoma, neuroblastoma, glioblastoma and head and neck squamous cell carcinoma (HNSCC) cells. In combination with irradiation it has been shown to have an additive effect on growth inhibition in melanoma cells. In this study, the radiosensitizing effect of betulinic acid on sequential irradiation was investigated in HNSCC cell lines. MATERIAL AND METHODS: Two HNSCC cell lines, SCC9 and SCC25, were treated with increasing doses of betulinic acid and sequentially irradiated with a single boost of 4 Gy from a conventional radiation source. The cells were counted, the surviving fraction was determined, and colony-forming assays were performed. RESULTS: It could be shown that betulinic acid alone inhibits cell survival, affects cell survival additively in combination with irradiation and decreases clonogenic survival in both cell lines when applied alone. CONCLUSION: Betulinic acid could be a promising treatment agent in radioresistant head and neck cancer. A combination of betulinic acid with radiotherapy seems to be beneficial.

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.