The accessory parotid gland (APG, Vth level) differs in histological structure from main parotid tissue. This gives rise to the hypothesis, mirrored in clinical observations, that the representation of tumours is different than in the rest of the gland. The aim of the study was to analyse the epidemiological and histological differences of parotid tumours located in regions I–V, with particular emphasis on the distinctiveness of region V. To define the epidemiological factors that will indicate the risk of histological malignancy from clinically benign appearance, multicentre prospective studies conducted between 2017–2021 by five Head and Neck Surgery University Departments, cooperating within the Polish Salivary Network Database 1929 patients (1048 women and 881 men), were included. The age, gender, patient occupation, place of inhabitation, tumour size, clinical features of malignancy, histology, and facial nerve (FN) paresis were analysed for superficial (I_II) and deep (III_IV) lobes and with special regard to the tumours affecting region V. Twenty eight tumours were located exclusively in region V (1.45% total) and seventy-two tumours were found in region V exhibiting extensions to neighbouring regions (3.7% total), characterised as significantly younger and less frequent in retirees. In I–IV regions, approximately 90% of tumours were benign, with pleomorphic adenoma (PA) and Whartin tumour (WT) predominance. In region V, PA exceeded 75% but WT were casuistic (2/28). Incidences of malignancies in region V was 40% but clinical signs of malignancy were evident only in tumours > 4 cm or in the presence of FN paresis. In 19% of patients with a benign appearance, imaging revealed malignancy; however, 38% of patients showed false negative results both in terms of clinical and radiological features of malignancy. Logistic regression models in 28 patients with tumours located exclusively in region V vs. 1901 other patients and in 100 patients with V extension vs. 1829 other patients showed no clinical symptoms of malignancy binding with final malignant tumour histology as a single variable or in combination with other variables. The logistic regression models obtained in this study show strong linkage between tumour location and predictors (age, male gender, and tumour diameter) and also aimed to function as a good classifier. Our conclusion is that, despite the very clear image of the mid-cheek tumour which is easily accessible in palpation and ultrasound examination, it is necessary to improve oncological vigilance and preoperative patient preparation.

Backgrounds/Objectives: Parotid gland tumors (PGTs) with parapharyngeal space (PPS) involvement have a specific clinical course and they can be a great challenge for surgeons, especially due to more difficult approaches and the risk of serious complications. The aim of this study is to present the characteristics of PGTs with PPS involvement. Methods: Retrospective, multicenter analysis of 1954 primary PGTs from 5 years (2017–2021) was performed. Comparative analysis was performed between groups with and without PPS involvement and included the following clinical and histopathological data: age, sex, place of residence, tumor size, FNAC result, percentage of malignant tumors, histological diagnosis, radicality of resection, and postoperative facial nerve (FN) dysfunction. Results: PPS involvement was found in 114 patients (5.83%). Secondary tumors affecting the deep lobe or the entire gland were predominant (46 and 60 cases, respectively). In a univariate analysis of tumors with and without PPS involvement, statistically significant differences were found in their size > 4 cm (12.97% vs. 37.72%), percentage of malignant tumors (7.12% vs. 17.55%), incidence of Warthin Tumors (WTs) (43.58% vs. 24.56%), percentage of R1 resection (5.53% vs. 12.50%), and rate of FN paresis (17.15% vs. 53.34%). Multivariate analysis showed that tumors with PPS involvement were statistically significantly characterized by larger size (tumors > 4 cm were 2.9 times more frequent), 2 times less frequent occurrence of WTs, and 1.6 times higher risk of FN paresis. Conclusion: PGTs with PPS involvement show certain clinical and histological differences and require more complex surgical accesses. Therefore, they cannot be treated as "ordinary" tumors occupying the deep lobe.

Facial nerve (FN) palsy is the most serious complication of parotid gland surgery, with risk influenced by tumor size, location and pathology. To assess the incidence, severity, duration, and risk factors of FN palsy following parotidectomy, based on the Polish Salivary Network Database. This multicenter study included 2650 patients treated surgically between 2018 and 2022. FN function was evaluated using the House-Brackmann scale, consider-ing extent, severity and duration of FN dysfunction. Multiple potential risk factors were examined. FN palsy occurred in 20% of patients: 17.2% transient and 4.5% permanent. The marginal mandibular branch was most frequently affected. Multivariate analysis showed that parapharyngeal space involvement, presence of malignant neoplasm and preoperative FN dysfunction independently predicted complete paralysis. Additional risk factors for more extensive, severe, and prolonged FN impairment included clinical signs of malignancy, prior radiation, non-radical margins, larger tumor size (>4 cm), and advanced stage of malignancy. A greater number of affected regions (defined by the European Salivary Gland Society (ESGS) classification) was identified as the most significant adverse risk factor for both the degree and persistence of postoperative facial nerve palsy. FN palsy remains a relevant risk in parotid surgery, particularly with large or malignant tumors. Early diagnosis and radical excision of smaller lesions are key to preserving nerve function.

Background/Objectives: The multitude of histological and genetic features of salivary gland malignancies (SGMs) hampers the ability of the doctors’ board to make a clear and quick decision on how aggressively treatment should be initiated. Despite treatment guidelines, it is difficult to determine the appropriate extent and invasiveness of surgery based on preliminary patient data. The aim of this study is to define the factors that have a significant impact on the oncological outcome of SGM treatment and to create an algorithm for finding the combinations of predictors with a particularly unfavorable impact on survival. Methods: A multicenter retrospective analysis was conducted on 2653 patients with salivary gland tumors (SGTs), including 229 with SGMs (parotid 204/229 = 89.1%; submandibular 25/229 = 10.9%), treated at seven Polish university departments from 2015 to 2022. All patients, except those with malignant lymphoma, underwent surgery followed by radiotherapy. Seventeen potential survival-impacting variables were analyzed: thirteen preoperative and four surgical specimens. The preoperative group aids in deciding surgical aggressiveness, while the postoperative group supports decisions on adjuvant treatment escalation. The main outcome measures were disease-free survival (DFS) and overall survival (OS). Results: SGMs constituted 8.63% of all SGTs, with 204 (89%) in the parotid and 25 (11%) in the submandibular glands. The average age was 63.38 years, with a male predominance (54%). Clinical and radiological signs of malignancy were reported in 45.4% and 54.6% of patients, respectively, with facial nerve palsy reported in 13%. Postoperative specimens revealed 23 histological types, and R0 resections were achieved in 168/229 cases (73%). Fifty-six patients (24.5%) died of cancer within five years. Significant survival factors included gender, urban residence, previous chemical and radiation exposure, clinical malignancy symptoms, pT-stage, pN-stage, clinical stage, and resection margins. Conclusions: The prognosis for SGM remains unsatisfactory, which would suggest more aggressive treatment; thus, carefully collected clinical data could support the decision-making process. Significantly worse survival has been demonstrated in the presence of unfavorable clinical factors, so defining new elements of medical history may be a step towards improving treatment outcomes.