p53 oncoprotein accumulation in adenoid cystic carcinoma of parotid and palatine salivary glands

Prognostic Significance of Histopathological Parameters for Salivary Gland Adenoid Cystic Carcinoma

Adenoid cystic carcinoma (ACC) is a rare salivary gland tumor that accounts for approximately 1% of all head and neck cancers. Despite its initial indolent behavior, long-term survival is poor due to locoregional recurrence in approximately 40% and distant metastasis in up to 60% of patients who undergo radical treatment. The histological parameters of ACC and the combination of these parameters in histopathological grading systems provide valuable prognostic information about the clinical course of the disease. Within this context, this review aims to analyze the impact of histopathological parameters, individual or combined in histopathological grading systems of malignancy, on ACC prognosis. Individual histopathological parameters such as solid pattern, presence of tumor necrosis, high-grade transformation, dominance of the epithelial component, presence of perineural and lymphovascular invasion, and positive surgical margins have negative impacts on the survival of patients with ACC. There are currently four histopathological grading systems for ACC; however, few studies have validated these systems and most of them explored small cohorts with short follow-up. Considering that the application of grading systems has been associated with ACC prognosis, a broader validation will allow not only their use for prognostic prediction but also assist in treatment planning.

Prognostic significance of p53 immunohistochemical expression in adenoid cystic carcinoma of the salivary glands: a meta-analysis

Adenoid cystic carcinoma of salivary glands is a rare adenocarcinoma and has been placed in “high-risk” category as poor long-term prognosis. The purpose of this study was to investigate p53 protein expression in adenoid cystic carcinoma of salivary glands and its correlation with clinicopathological parameters and prognosis. Literatures were searched from PubMed, Embase, Cochrane Library and Web of Science, which investigated the relationships between p53 expression and pathological type, clinical stage, local recurrence, metastasis, nerve infiltration and overall survival. A total of 1,608 patients from 36 studies were included in the analysis. The results showed that p53-postive expression rate was 49% in adenoid cystic carcinoma of salivary glands (OR=10.34, 95%CI: 4.93-21.71, P < 0.0001). The p53-postive expression was closely related to tumor types (OR=0.30, 95%CI: 0.14-0.65, P < 0.0001). The tumor with solid histological subtype had a strong positive correlation with p53 expression. The combined analysis revealed that the p53-positive expression rate among patients in T1and T2 stage was 41.4%, compared to 53.2% among those in T3 and T4 stage. However, there was no significant correlation between tumor stage and p53 expression (OR=0.47, 95% CI: 0.17-1.29, P = 0.14). Besides, compared to patients with p53-negative expression, those with p53-positive expression had a greater chance of developing metastasis, local recurrence and nerve infiltration as well as poorer 5-year overall survival (P < 0.01). In conclusion, the p53 expression is related to the survival of adenoid cystic carcinoma of salivary glands. It can be considered as the auxiliary detection index in treatment and prognosis of adenoid cystic carcinoma of salivary glands.

VEGF and Ki-67 Overexpression in Predicting Poor Overall Survival in Adenoid Cystic Carcinoma

Purpose

The purpose of this study was to evaluate potential prognostic factors in patients with adenoid cystic carcinoma (ACC).

Materials and Methods

A total of 68 patients who underwent curative surgery and had available tissue were enrolled in this study. Their medical records and pathologic slides were reviewed and immunohistochemistry for basic fibroblast growth factor, fibroblast growth factor receptor (FGFR) 2, FGFR3, c-kit, Myb proto-oncogene protein, platelet-derived growth factor receptor beta, vascular endothelial growth factor (VEGF), and Ki-67 was performed. Univariate and multivariate analysis was performed for determination of disease-free survival (DFS) and overall survival (OS).

Results

In univariate analyses, primary site of nasal cavity and paranasal sinus (p=0.022) and Ki-67 expression of more than 7% (p=0.001) were statistically significant factors for poor DFS. Regarding OS, perineural invasion (p=0.032), high expression of VEGF (p=0.033), and high expression of Ki-67 (p=0.007) were poor prognostic factors. In multivariate analyses, primary site of nasal cavity and paranasal sinus (p=0.028) and high expression of Ki-67 (p=0.004) were independent risk factors for poor DFS, and high expression of VEGF (p=0.011) and Ki-67 (p=0.011) showed independent association with poor OS.

Conclusion

High expression of VEGF and Ki-67 were independent poor prognostic factors for OS in ACC.

Histopathological grading of adenoid cystic carcinoma of the head and neck: analysis of currently used grading systems and proposal for a simplified grading scheme

BACKGROUND

Histopathological grading of adenoid cystic carcinoma (ACC) is a controversial issue. It is generally agreed that solid type ACC has a relatively poor prognosis. However, the amount of solid regions within this often mixed type tumor that predicts a poor prognosis is not firmly established. Some authors stipulate that the presence of a solid component regardless of the amount is a poor prognosticator where others argue that the amount should be taken into consideration. Two grading systems most commonly used are those described by Perzin et al./Szanto et al. and Spiro et al., respectively. They report that prognosis of ACC is poor if >30% and >50% of the tumor volume has a solid growth pattern, respectively.

MATERIAL AND METHODS

The described grading systems are applied to a series of 81 surgically treated cases of ACC at the VU University Medical Center, Amsterdam, The Netherlands. Moreover, we introduced an alternative grading system, in which the presence of a solid component, irrespective of its amount, is considered. All three systems of grading were tested for inter-observer concordance and prediction of prognosis.

RESULTS

Inter-observer concordance for grading ACC according to Perzin et al./Szanto et al. and Spiro et al., proved to be moderate with Kappa Scores of 0.393 and 0.433, respectively. Our alternative grading system yielded inter-observer concordance with a Cohen's kappa result of 0.990. All systems were comparable in discriminating patients with poor clinical outcome. Histopathological grade proved to be an independent prognosticator.

CONCLUSION

The presence of any solid component in ACC is a negative prognosticator, and can histopathologically be diagnosed with a high reliability. These results suggest to merely register the presence or absence of a solid tumor component since its inter-observer variability is very low, its reproducibility is high and its predictive value is comparable to the traditional grading systems used.

Prognostic significance of Ki-67 and p53 as tumor markers in salivary gland malignancies in Finland: an evaluation of 212 cases

The proliferative capacity of a tumor as measured by Ki-67 nuclear antigen is one of the most powerful indicators of tumor behavior. Ki-67 is considered a useful tool in determining the aggressiveness of malignant neoplasms. p53 tumor suppressor gene mutations have been linked with the development and progression of a number of various cancer types. p53 tumor suppressor protein and the volume corrected index of Ki-67 corresponding to Ki-67 /mm2 of tumor tissue (VCI Ki-67) in salivary gland tumors were evaluated by immunohistochemistry from paraffin embedded sections in a series of 212 patients. The follow-up time in this nationwide full population-based study was up to five years. The association of clinicopathological features and the results of present study with survival were examined. In multivariate analysis high VCI Ki-67 was associated with worse survival of SGC patients (p = 0.0114). Supplementary information was brought by age (p = 0.0002), lymph node status (p = 0.0014), gender (p = 0.0017) and stage (p = 0.0191). p53 expression did not have additional value in prediction of survival (p = 0.1433) compared to the commonly clinical used parameters. In this material consisting of various salivary gland carcinomas VCI Ki-67 was a good prognostic factor for survival.

Expression of RUNX3 in salivary adenoid cystic carcinoma: implications for tumor progression and prognosis

Runt-related transcription factor-3 (RUNX3), being a tumor suppressor gene in gastric cancer, plays an important role in inhibiting cellular growth by participating in the transforming growth factor-beta-dependent apoptosis. The aim of this study was to determine the expression of RUNX3 in normal salivary glands and adenoid cystic carcinomas (ACCs), comparing the results with clinicopathological factors and patient survival. The quantitative reverse transcription-polymerase chain reaction (RT-PCR) analysis and Western blot analysis revealed the expression of RUNX3 both in normal salivary glands and ACCs. Nuclear and cytoplasmic immunoreactivities against RUNX3 in ductal luminal cells and acinous cells, but immunonegative in myoepithelial cells, were detected in normal salivary glands. In ACC, the RUNX3 immunostaining was shown in the cytoplasm of tumor cells; however, no nuclear location of RUNX3 was found. Lower RUNX3 expression showed significant correlation to distant metastasis and histological growth pattern (P = 0.009 and P = 0.025, respectively). On univariate analysis, low level of RUNX3 immunolabeling (P = 0.012), stage T4 (P = 0.017), lymph node involvement (P = 0.007), and distant metastasis (P < 0.001) were significantly associated with decreased overall survival. Multivariate analysis showed only distant metastasis had an independent prognostic effect on overall survival (P = 0.043). Our results demonstrate the expression of RUNX3 in normal salivary glands and salivary ACCs. The low level of RUNX3 protein in salivary ACCs might play a pivotal role in tumor progression and have prognostic values in ACCs.

Salivary gland cancers: current treatments, molecular characteristics and new therapies

Salivary gland cancers are relatively rare and quite diverse. Current therapy relies on local ablation. There are few large clinical trials or randomized trials to guide treatment, especially for metastatic disease. This article reviews the epidemiology, staging, molecular characteristics, and treatment evidence for the most common types of salivary cancers and suggests potential future diagnostic and treatment directions. Progress in understanding the molecular and cell biology of salivary gland cancers may lead to the development of targeted therapies in these rare tumors. Multidisciplinary and multi-institutional collaborative studies are needed to help improve survival in salivary gland cancers.

DNA copy number gains at loci of growth factors and their receptors in salivary gland adenoid cystic carcinoma

PURPOSE

Adenoid cystic carcinoma (ACC) is a malignant salivary gland tumor with a high mortality rate due to late, distant metastases. This study aimed at unraveling common genetic abnormalities associated with ACC. Additionally, chromosomal changes were correlated with patient characteristics and survival.

EXPERIMENTAL DESIGN

Microarray-based comparative genomic hybridization was done to a series of 18 paraffin-embedded primary ACCs using a genome-wide scanning BAC array.

RESULTS

A total of 238 aberrations were detected, representing more gains than losses (205 versus 33, respectively). Most frequent gains (>60%) were observed at 9q33.3-q34.3, 11q13.3, 11q23.3, 19p13.3-p13.11, 19q12-q13.43, 21q22.3, and 22q13.33. These loci harbor numerous growth factor [fibroblast growth factor (FGF) and platelet-derived growth factor (PDGF)] and growth factors receptor (FGFR3 and PDGFRbeta) genes. Gains at the FGF(R) regions occurred significantly more frequently in the recurred/metastasized ACCs compared with indolent ACCs. Furthermore, patients with 17 or more chromosomal aberrations had a significantly less favorable outcome than patients with fewer chromosomal aberrations (log-rank = 5.2; P = 0.02).

CONCLUSIONS

Frequent DNA copy number gains at loci of growth factors and their receptors suggest their involvement in ACC initiation and progression. Additionally, the presence of FGFR3 and PDGFRbeta in increased chromosomal regions suggests a possible role for autocrine stimulation in ACC tumorigenesis.

Salivary gland adenoid cystic carcinoma: A review of chemotherapy and molecular therapies

Adenoid cystic carcinoma (ACC) accounts for about 1% of all head and neck malignancies. It has a tendency for a prolonged clinical course, with local recurrences and distant metastases sometimes occurring many years after presentation. Standard treatment for salivary gland ACC is surgery and post-operative radiotherapy. The aim of this review was to examine the reported efficacy of various chemotherapy regimens and molecular therapies on recurrent/metastatic salivary gland ACC. One hundred and fourteen publications were reviewed on chemotherapy as well as possible molecular targets of therapy, including KIT, epidermal growth factor receptor (EGFR), human epidermal growth receptor-2 (HER-2), oestrogen and progesterone receptors, proliferating cell nuclear antigen (PCNA), Ki-67 and the p53, bcl-2 and SOX-4 genes. Reported response rates to combination chemotherapy are low and response duration generally short lived. The response to molecular therapies is low also. More research into novel molecular targets is needed.

Prognostic factors in head and neck adenoid cystic carcinoma

The aim of this study was to analyse the clinical, histological and immunohistochemical prognostic factors of a large series of adenoid cystic carcinoma, using univariate and multivariate survival analyses. All cases of head and neck ACC (n = 129) treated in a single institution in Brazil, between 1955 and 1997, were selected for the study. Univariate survival analysis revealed that age older than 45 years (p = 0.04), period of complaints inferior to 18 months (p = 0.007), presence of paresthesia (p = 0.04), T stage (p = 0.01), N stage (p = 0.04), M stage (p < 0.001), clinical stage (p = 0.003), solid histological type ( p< 0.001), presence of residual tumor (p < 0.001) and expression of p53 (p = 0.08) correlated with a poor prognosis. In the multivariate survival analyses, clinical stage, solid histological subtype and increased expression of p53 were independent significant prognostic factors. According to our findings, clinical stage, solid growth pattern and expression of p53 were the most important prognostic factors in patients with ACC.

Copy number gains on 22q13 in adenoid cystic carcinoma of the salivary gland revealed by comparative genomic hybridization and tissue microarray analysis

Adenoid cystic carcinoma (ACC) of the salivary gland is a neoplasm characterized by slow but inevitable local progression and terminal hematogenous metastasis. To detect novel imbalanced chromosomal regions associated with tumorigenesis, we used chromosomal comparative genomic hybridization to screen 27 ACC. The most common aberration was copy number gain of 22q13 (nine cases) followed by gains of 16p (seven cases) and 17q (four cases) and copy number losses on 6q (six cases). To further delineate the prevalence of 22q13 copy number gains in ACC, fluorescence in situ hybridization was performed for five bacterial/phage artificial chromosome (BAC/PAC) probes from the 22q13 consensus region with 57 ACC on a tissue microarray. The overall prevalence of copy number gains on 22q13 was 30% of the tumors in the fluorescence in situ hybridization analysis, irrespective of histologic differentiation (cribriform/tubular vs. solid) or tumor event (primary vs. recurrent). We therefore assume that copy number gain of 22q13 is a novel frequent finding in ACC that may be involved in the initial pathogenesis of this neoplasm by proto-oncogene activation.

p53, bcl-2 and Ki-67 expression in adenoid cystic carcinoma of the palate. A clinico-pathologic study of 21 cases with long-term follow-up

Adenoid cystic carcinoma (ACC) is an indolent tumor that pursues a protracted clinical course with recurrences and late metastases. The aim of this study was to investigate immunohistochemically the expression of p53, bcl-2 protein, and Ki-67 in 21 cases of ACC of the palate, all with a minimum of 10 years and a maximum of 22 years of clinical follow-up. These results were also analyzed with regard to different clinical prognoses of the histologic subtypes of ACC. High expression of p53 and bcl-2 was noted in 19 out of 21 ACC cases (90%), in which most tumor cells (from 66% to 99%) proved to be immunopositive. A relation to the histologic types, clinical staging, and survival was not found. Therefore, the high immunoreactivity against these oncoproteins in the same tumor cells suggests that these two oncogenes may be involved since the early stage of carcinogenesis. Loss of function of the p53 protein combined with bcl-2 upregulation might give the tumor cells a double growth advantage, because uncontrolled proliferation is combined with a reduced cell death rate. The interaction with other oncogenes may then trigger a multistep process able to promote tumor progression. The low labeling index Ki-67 was detected in nine out of 21 cases (42%), with a low percentage of tumor cells (from 3% to 15%) being positive, whereas the remaining 12 cases were negative. We found no relation to the histologic types, clinical staging, and survival; however, the low proliferation rate could explain the natural course of tumor.

PCNA, Ki-67 and p53 expressions in submandibular salivary gland tumours

Salivary gland tumours are uncommon with a broad heterogeneity. The most common benign tumour is the pleomorphic adenoma, whereas mucoepidermoid carcinoma and adenoid cystic carcinoma predominate among the malignancies. Most salivary gland tumours occur in the parotid, and consequently clinical and biological data are normally derived from this site. This work describes the expressions of PCNA, Ki-67 and p53 in 15 pleomorphic adenomas, 15 mucoepidermoid carcinomas and 15 adenoid cystic carcinomas of the submandibular gland. Our results showed that all pleomorphic adenomas were negative for p53 and Ki-67 with 66.6% being positive for PCNA. Conversely, p53 was positive in 53% of the mucoepidermoid carcinomas and in 20% of the adenoid cystic carcinomas. Ki-67 was expressed in 47.7% of the mucoepidermoid carcinomas and 40% of the adenoid cystic carcinomas. All malignant tumours were positive for PCNA. These results indicate that the proliferative rate analysed with PCNA and Ki-67 and the expression of p53 in pleomorphic adenoma and adenoid cystic carcinoma of the submandibular gland were similar to those described in the parotid and minor salivary glands. However, mucoepidermoid carcinomas showed higher expression of these markers than those of other salivary glands. This work is the first describing the expression of these immunohistochemical markers exclusively in submandibular salivary gland tumours.

p53 expression, growth, and spontaneous metastasis of the human GI 101 breast carcinoma in athymic nude mice

The human GI 101 breast carcinoma cell lines produces spontaneous metastasis to the lungs when xenografted subcutaneously in female athymic nude mice. To establish the time-course of tumor growth and distant metastasis to the lungs and axillary lymph nodes, 5 mm3 of tumor tissue was implanted in the subaxial region of female athymic nude mice. Micrometastases in the lung were first detected 3 weeks after tumor implantation. The incidence of lung metastasis and the number of tumor emboli were correlated with the volume of the primary tumors. Ipsilateral axillary lymph node metastasis was observed within 17 weeks, indicating that metastasis to the lymph node is a later event. Unlike pulmonary micrometastases which were in the form of clusters of four to six tumor cells, metastasis to the lymph nodes were in nodules of poorly differentiated and larger tumor cells. Immunohistochemistry evaluation of p53 oncoprotein in the primary and metastatic tumor cells showed different patterns of subcellular accumulation. Cytoplasmic staining was mainly detected in the primary and secondary tumor cells disseminated to the lungs. In contrast, nuclear staining was only detected in tumor cells infiltrated to the axillary lymph nodes. There was no gain of loss of positivity of p53 accumulation (i.e., qualitative measurements) as the tumor grew in size. The data indicate that the GI 101 tumor cells could be used as a useful model for studying the malignant progression of hormone-independent breast cancer, antimetastatic drugs, and early events in tumor metastasis.

Adenoid cystic carcinoma: use of cell proliferation, BCL-2 expression, histologic grade, and clinical stage as predictors of clinical outcome

BACKGROUND

Although the three basic histologic growth patterns of adenoid cystic carcinomas (tubular, cribriform, and solid) provide some indication of clinical outcome, additional, perhaps superior, predictors of biologic activity are needed for patient management.

METHODS

This series is composed of 31 adenoid cystic carcinomas that presented in Linköping between 1982 and 1997. The tumors were clinically staged and histologically graded. For each case, after immunohistochemical identification, the proportion of tumor cells expressing the cell cycle markers MIB-1 and bcl-2 (as an indicator of proliferation and apoptosis, respectively) were quantified. Statistical correlation was sought between tumor stage and grade and the two cell cycle markers.

RESULTS

The proportions of cycling tumor cells in adenoid cystic carcinomas ranged from 0.3% to 55%. For patients with no evidence of disease and a follow-up of at least 5 years, the mean percent MIB-1 value was significantly lower than for those patients who were alive with local recurrence and/or metastasis or who had died from their adenoid cystic carcinoma (p =. 024). MIB-1 tumor cell positivity also correlated strongly with tumor grade (p =.053), but not with stage (p =.22). Neither clinical stage nor histologic grade correlated with the degree of bcl-2 tumor cell positivity (p =.97 and p =.49, respectively).

CONCLUSIONS

Staging and grading continue to play a vital role in the management of patients with adenoid cystic carcinoma. Furthermore, in this series of patients with adenoid cystic carcinoma, a cycling tumor cell population as measured by the MIB-1 antibody greater than 10% indicates this group as biologically more aggressive and at an increased risk for a fatal course.