Clinicopathologic and Surgical Study of Pleomorphic Adenoma of the Parotid Gland: Analysis of Risk Factors for Recurrence and Facial Nerve Dysfunction.

PURPOSE: To determine whether clinicopathologic or surgical features are risk factors for recurrence and facial nerve dysfunction in pleomorphic adenoma (PA) of the parotid gland. PATIENTS AND METHODS: The records of 198 patients surgically treated for a PA of the parotid gland from 1999 through 2013 were retrospectively reviewed to identify patients who developed a tumor recurrence. The Fisher exact test and Mann-Whitney U test were used to analyze patient characteristics between recurrent and non-recurrent PAs. Logistic regression was used to determine the risks of recurrence and facial nerve dysfunction. RESULTS: Twenty-three patients (11.6%) developed a recurrence. Patients with tumor recurrence were notably younger than patients without recurrence. Of the 14 patients who underwent enucleation, 11 (78.6%) developed residual disease, as did 10 of 165 patients (6%) managed by a superficial parotidectomy (P < .0005). Furthermore, the risk of residual disease was 9.3 to 21.6 times higher in patients who underwent enucleation than in those who underwent a total or superficial parotidectomy. For tumor histology, recurrence was observed in 3 (15.8%) of the 19 cellular types, 18 (11.5%) of 157 classic cases, and 1 (4.8%) of 21 myxoid cases (P = .5). The risk of recurrence with positive resection margins was 49 times higher than with negative margins (P = .001). CONCLUSION: Young age, enucleation, and positive margins are risk factors for residual pleomorphic adenoma, and surgical technique and histomorphologic features are associated with increased facial nerve dysfunction.

Expression of the voltage-gated potassium channel Kv3.4 in oral leucoplakias and oral squamous cell carcinomas.

AIMS: The expression of the voltage-gated potassium channel Kv3.4 was investigated in both oral squamous cell carcinomas (OSCC) and oral leucoplakias to establish its clinical significance during the development and progression of OSCC. MATERIALS AND METHODS: Tissue specimens from 62 patients with oral leucoplakia were collected prospectively and 100 patients with OSCC who underwent surgical treatment were collected retrospectively, and Kv3.4 expression was analysed by immunohistochemistry. RESULTS: Thirty-nine of 100 tumours exhibited Kv3.4-positive expression, and staining was associated with the degree of differentiation (P = 0.05) but showed no impact on patient prognosis. Abnormal Kv3.4 expression was detected in 16% (7 of 43) hyperplastic lesions and at a significantly higher proportion in oral dysplasias (50%, 8 of 16 cases; P = 0.008), whereas expression was negligible in normal adjacent epithelia. Furthermore, patients carrying Kv3.4-positive lesions exhibited a higher progression risk than those with Kv3.4-negative lesions; however, histology but not Kv3.4 expression predicted oral cancer development significantly in this prospective cohort. CONCLUSION: This study provides original evidence to demonstrate the early occurrence and high prevalence of abnormal Kv3.4 expression in oral leucoplakias. Our results support a role for Kv3.4 potassium channel in OSCC tumorigenesis rather than tumour progression and disease outcome.

Relevance of level IIb neck dissection in oral squamous cell carcinoma.

BACKGROUND: The purpose of this study was to determine the prevalence of level IIb metastasis in patients with oral squamous cell carcinomas (OSCCs). MATERIAL AND METHODS: A prospective analysis of 56 patients with OSCC who underwent surgical treatment of the primary lesion with simultaneous neck dissection was performed. During neck dissection, level IIb lymph nodes were separately removed and processed. Neck dissection was bilateral in 26 patients (46%) and unilateral in 30 patients (54%). RESULTS: The mean number of nodes found in the level IIb specimens was 4.7 (range: 0-8 nodes). The prevalence of metastasis at level IIb was 0% in pN0 necks and 3.4% in pN+ necks, with an overall prevalence of 1.8%. A significant association between metastasis to level IIb and type of neck dissection was observed. There were no isolated metastases to level IIb without the involvement of other nodes in the remaining neck specimen. Four regional recurrences were observed during follow-up. CONCLUSIONS: Based on our findings, we suggest that dissection of the level IIb region in patients with OSCC may be required only in patients with multilevel neck metastasis or if level IIa metastasis is found intraoperatively.

HERG1 potassium channel expression in potentially malignant disorders of the oral mucosa and prognostic relevance in oral squamous cell carcinoma.

BACKGROUND: HERG1 potassium channel plays a critical role in the cell proliferation. METHODS: HERG1 protein expression was analyzed by immunohistochemistry (IHC) in 62 patients with oral leukoplakias and 100 patients with oral squamous cell carcinomas (OSCC). HERG1 mRNA levels were assessed by real-time reverse transcriptase-polymerase chain reaction (RT-PCR) in 22 patients with primary head and neck squamous cell carcinoma (HNSCC). RESULTS: Statistically significant associations were found between HERG1 expression and tobacco consumption, disease stage, tumor differentiation, tumor recurrence, and reduced survival. There was no association between HERG1 expression and the risk of progression from oral leukoplakia to OSCC. In addition, a high proportion of tumors (80%) showed increased HERG1 mRNA levels compared to normal mucosa from nononcologic patients. CONCLUSION: Aberrant HERG1 expression increases as oral tumorigenesis progresses from oral hyperplasia to OSCC. Increased HERG1 mRNA levels were also frequently detected in OSCC and other HNSCC subsites. HERG1 expression emerges as a clinically relevant feature during tumor progression and a potential poor prognostic biomarker for OSCC. © 2016 Wiley Periodicals, Inc. Head Neck 38: 1708-1716, 2016.

Modified facelift approach combined with a superficial musculoaponeurotic system flap in the treatment of benign parotid tumors.

PURPOSE: The purpose of this study was to investigate the adequacy of a modified facelift incision combined with an SMAS flap for the resection of benign parotid lesions in terms of cosmesis and incidence of Frey's syndrome. MATERIALS AND METHODS: A hundred patients who underwent superficial parotidectomy were divided into 2 groups according to approach: Blair incision (57 cases) and modified facelift incision (43 cases). In the latter group, 36 patients were reconstructed with a superficial musculoaponeurotic system (SMAS) flap. During follow-up, patients were asked to rate their satisfaction with their postoperative appearance using a 1 to 3 scale. RESULTS: Clinical Frey's syndrome was present in 8.5% of patients with SMAS flap, and in 19% patients without SMAS flap (p = 0.16). The average cosmetic outcome score for patients who underwent a modified facelift approach combined with an SMAS flap was 2.87, whereas patients whose tumors were approached through a Blair incision reported a lower score of 2.1 (p < 0.005). CONCLUSION: A modified facelift incision combined with an SMAS flap improved the cosmetic appearance of patients who underwent extrafacial or superficial parotidectomy. In addition, this flap seems to reduce the occurrence of Frey's syndrome.

The prognostic role of claudins -1 and -4 in oral squamous cell carcinoma.

Claudin dysregulation has been described in various tumor types; however, its clinical relevance is poorly understood. We present a study in which we assessed the expression of claudin 1 (CLDN1) and CLDN4 in oral squamous cell carcinoma (OSCC), as well as their prognostic relevance. Immunohistochemical analysis of CLDN1 and CLDN4 expression was carried out on tissue sections from 65 OSCCs. The presence of CLDN1 in the invasive front of tumor islands was associated with neck node metastasis, and the expression of CLDN4 was associated with higher histological grade, and tumor recurrence. Membranous staining for CLDN4 in tumor cells, and weak intensity of CLDN4 immunoexpression were predictive for poorer survival. In a multivariate analysis for disease recurrence, CLDN1 immunostaining was statistically significant. Specifically, CDLN1 expression in the tumor invasive front was associated with tumor recurrence. Our results indicate that CLDN4 expression is correlated with poor prognosis, and CLDN1 expression may be an indicator of recurrence of OSCC.