Immunohistochemical Expression of p53 in Pleomorphic Adenoma and Carcinoma Ex Pleomorphic Adenoma

Molecular Factors in Carcinoma Ex Pleomorphic Adenoma: Systematic Review and Meta-Analysis

OBJECTIVE

Carcinoma ex pleomorphic adenoma (CXPA) is a rare malignant salivary gland tumor. Although multiple reviews have been published on salivary gland malignancies, it has been a decade since the last dedicated systematic review pertaining to CXPA alone was published. This study examines molecular factors in CXPA diagnosis.

DATA SOURCES

MEDLINE, CINAHL, Embase, Scopus, Web of Science (BIOSIS), Cochrane CENTRAL, Health Collection (Informit), OpenDOAR, and GreyNet International.

REVIEW METHODS

Systematic review and meta-analysis from inception to October 31, 2022 for all English language studies pertaining to "carcinoma ex pleomorphic adenoma." Predicted incidence of each biomarker was calculated with meta-analysis. Comparison against pleomorphic adenoma (PA) and salivary duct carcinoma (SDC) when reported within the same study are performed. Risk of bias performed with JBI tool for prevalence studies.

RESULTS

Of 19151 unique studies undergoing abstract screening, 55 studies (n = 1322 patients) underwent data analysis. Biomarkers with >3 studies were p53, HER2, AR, EGFR, PLAG1, ERBB, ER, PR, HMGA2, p16, p63, a-SMA, RAS, PTEN, PDL1, BRAF, PIK3CA, and c-kit. Highest incidence was seen in AR, EGFR, p16, and p53. Significant differences were demonstrated compared with PA and SDC. There was high heterogeneity and overall high risk of bias within studies.

CONCLUSION

Molecular factors are an area of interest in the diagnosis of CXPA. Our study results support examining CXPA as a discrete cohort in future targeted therapy trials. Laryngoscope, 134:1042-1053, 2024.

CD24-gold nanocomposite as promising and sensitive biomarker for cancer stem cells in salivary gland tumors

Cancer stem cells are highly tumorigenic cells in the majority of the tumor that are responsible for the initiation, rapid growth, invasion, metastasis, and therapeutic resistance associated with various human cancers. The aim of this project is to assess a diagnostic and prognostic biomarker for the detection of cancer stem cells in salivary gland tumors using gold nanoparticles that are synthesized and conjugated to CD24 primer to form a CD24-Gold Nanocomposite. Sixty cases were included (29 pleomorphic adenoma, 19 carcinoma ex pleomorphic adenoma, and 12 normal controls). Alterations in biomarker expression between studied groups were analyzed and correlated with clinicopathological characteristics using Fisher's exact and Chi-square tests. ROC and Kaplan-Meier curves were used to validate diagnostic and prognostic values, respectively. This study confirms that CD24-Gold Nanocomposite served as a promising and highly sensitive biomarker in salivary gland tumor diagnosis and prognosis prediction.

Risk factors for carcinoma ex pleomorphic adenoma in patients presenting with recurrence after resection of pleomorphic adenoma

BACKGROUND

In patients presenting with recurrent pleomorphic adenoma (rPA), clinical evaluation can fail to recognize carcinoma ex PA (cxPA). We aim to identify the risk factors for cxPA.

METHODS

This is a single institution retrospective case-control study from 2000 to 2015. CxPA was diagnosed based on surgical pathology. Demographics, clinical, and social histories were collected.

RESULTS

A number of 13/106 (12.3%) patients were diagnosed with cxPA, of which only 4/13 (31%) had clinical features suspicious for malignancy. Compared to benign rPA, factors associated with cxPA included age >50 (odds ratio [OR] 6.67, 95% confidence interval [CI]: 1.71-25.98, P < .01), >10 pack-years of smoking history (OR 3.36, 95% CI: 1.01-11.14, P = .04), and the largest tumor being >2 cm on pathology (OR 4.42, 95% CI: 1.14-17.10, P = .03).

CONCLUSIONS

In patients presenting with rPA, risk factors for malignant transformation include age >50, significant smoking history, and tumors larger than 2 cm. Clinical signs of malignancy such as rapid growth or pain are not always present.

p53 expression in pleomorphic adenoma of salivary glands: A systematic review and meta-analysis

OBJECTIVE

There are conflicting data regarding immunohistochemical expression of p53 in pleomorphic adenoma. This systematic review and meta-analysis aimed to examine whether p53 expression has a role in the pathogenesis of pleomorphic adenoma.

DESIGN

A comprehensive literature search for relevant studies published from 2000 up to end of 2014 was performed using PubMed, EMBASE and the Cochrane Library Databases. Only articles in which p53 detected by immunohistochemical staining were included. The meta-analysis was done using Comprehensive Meta-Analysis software.

RESULTS

Eighteen eligible studies were included in this meta-analysis. Heterogeneity measures showed a statistically significant Cochrane Q value (P-value<0.001). The random effects model showed an effect size of 0.254 with a 95% CI (0.139-0.417). The overall p53 positivity is 25.4%.

CONCLUSION

Mutant p53 has to be detected by more precise techniques to emphasize on its role in development of pleomorphic adenoma of salivary gland.

Immunohistochemical expression of p16 in Carcinoma Ex-pleomorphic Adenoma (undifferentiated and Adenocarcinoma Types)

OBJECTIVE

This study was aimed at characterizing alterations in the immunohistochemical expression of p16 in carcinoma ex-pleomorphic adenomas.

STUDY DESIGN

A selected series of 27 cases of carcinoma ex-pleomorphic adenomas were examined.

RESULTS

The results showed that p16 expression in non tumour duct cells was strongly positive nuclear staining in 23 (85%) cases out of 27 cases, that 3 (11.1%) had moderate staining, and that 1 (3.7%) had weak staining. p16 expression in carcinoma ex-pleomorphic adenomas was indicated as a negative nuclear staining in 22 (81.4%) cases out of 27cases, and 5 (18.5%) cases expressed moderate staining.

CONCLUSION

This study suggests that alteration of p16 expression is detected in carcinoma ex-pleomorphic adenomas. p16 has a role in development of carcinoma ex-pleomorphic adenomas.

GSK3β and CREB3 gene expression profiling in benign and malignant salivary gland tumors

BACKGROUND

Salivary gland tumors (SGT) are rare lesions with uncertain histopathology. One of the major signaling pathways that participate in the development of several tumors is protein kinase A. In this pathway, glycogen synthase kinase β (GSK3β) and cAMP responsive element binding protein (CREB3) are two genes which are supposed to be down regulated in most human tumors. The expression level of the genes was evaluated in SGT to scrutinize their possible under expression in these tumors.

METHODS

Forty eight fresh tissue samples were obtained from patients with benign and malignant SGT, including pleomorphic adenoma, warthin's tumor, mucoepidermoid carcinoma (MEC), salivary duct carcinoma and carcinoma ex pleomorphic adenoma. Eight normal samples were used as controls. Quantitative real-time PCR was used to analyze the expression level of interest genes.

RESULTS

Data was analyzed by statistical methods. GSK3β was downregulate in all samples and all results were statistically significant (P<0.05). CREB3 did not show a significant decrease or increase in its mRNA expression, but the results were significant in MEC and salivary duct carcinoma.

CONCLUSION

GSK3β down regulation has been reported in many human tumors. This gene stimulates CREB3, inducing cell proliferation and oncogenesis. Our findings showed GSK β down regulation; however, CREB3 expression level was close to normal group. No association between CREB3 expression and inactivated GSK3β could be postulated in SGT.