Parotid salivary duct carcinoma: a single institution’s 20-year experience

Abstract

Purpose The aim of the study was to assess the treatment results of the parotid gland salivary duct carcinoma (SDC). Material and methods A retrospective clinicopathological analysis of 40 patients treated for parotid SDC in 1996–2015 was performed. The impact of following factors on 5-year disease-free survival (DFS) and overall survival (OS) was studied: age, sex, preoperative 7th nerve palsy, skin infiltration, pT, pN, surgical margin, type of parotidectomy and neck dissection, histology (SDC de novo vs. SDC ex pleomorphic adenoma, SDCexPA), intra/periparotid lymph nodes metastases, perineural invasion (PNI), extraparenchymal extension (EPE), and overexpression HER2. Results The average age of the patients was 62 years (ranged from 39 to 81). Males predominated (57.5%). Patients with the clinical stage IV predominated (82.5%). In 1/3 of patients preoperative, 7th nerve palsy occurred. All patients were treated surgically, and all but one had supplementary radiotherapy. In 28 patients (70%), total radical parotidectomy was performed. A neck dissection was performed in all patients. In 19 cases (47.5%), SDCexPA was diagnosed. Negative microscopic surgical margin was obtained in 60% of patients. The follow-up for the whole analyzed group ranged from 2 to 22 years, average was 11.6 years. In 23 patients (57.5%), the disease recurred. Local recurrence was observed in 10 (25%) and distant metastases in 15 (37.5%) cases. 20 patients (50%) died of cancer. 5-year DSF and OS were 42.5% and 41%, respectively. Univariate analysis proved that the significant influence on the survival had 7th nerve palsy ( p = 0.024 and p = 0.017, respectively), higher pT-stage ( p < 0.001), radical parotidectomy ( p = 0.024 and p = 0.022), radical treatment of the neck ( p = 0.001 and p = 0.002), EPE ( p = 0.040 and p = 0.028), and histology SDCexPA and PNI ( p = 0.036 and 0.048). Multivariate analysis showed that independent prognostic factors were the 7th nerve palsy and the histology SDCexPA, which worsened 5-year DFS, respectively, 3.61 and 3.94 times ( p = 0.033 and p = 0.026). On the other hand, on 5-year OS, only 7th nerve palsy had an influence (3.86 times worse prognosis, p = 0.033). Conclusions SDC is a clinically aggressive cancer with high risk of local recurrence and distant metastases, however, with a chance of curing of around 40%. In the majority of patients, a radical surgical treatment is necessary due to the high clinical stage of disease. Worse prognosis have patients with preoperative 7th nerve palsy and in whom SDC develops in pleomorphic adenoma.

A 10-year review of primary major salivary gland cancers

“…Kleinsasser et al [19] described SDC in 1968, as an aggressive adenocarcinoma which resembles high-grade breast ductal carcinoma. This entity has been increasingly diagnosed, and there is currently a growing interest from the scientific community, with multiple publications of institutional series [20][21][22][23][24][25][26][27][28][29][30]. Actually, SDC is characterised by a very aggressive behaviour, with high rates of local or distant recurrence and tumour-related death [31,32].…”

Parotid Salivary Duct Carcinoma With a Prominent Squamous Component: Immunohistochemical Profile, Diagnostic Pitfalls, and Therapeutic Implications

“…Originally described by Kleinsasser and colleagues in 1968, [1][2][3][4][5] SDC is a high-grade malignant neoplasm that often presents at an advanced stage with a propensity to metastasize early to regional lymph nodes and distant sites. While the etiology remains unknown, it is occasionally seen in the setting of obstructive sialadenitis and IgG4-related sclerosing disease of the parotid, and can arise from either de novo or ex pleomorphic adenoma.…”

“…[5][6][7] It commonly occurs in the parotid gland (83%) of men over the age of 50 years, 5,8 as a rapidly growing mass (35%) and often with cervical lymphadenopathy on presentation (20%). 4 Skin ulceration is seen in 15% of patients, and preoperative VII nerve palsy is seen in 33% of cases. [4][5][6] Histologically, it resembles high-grade ductal carcinoma of the breast, often with large ducts that display comedonecrosis and cribriform growth with "Roman bridge" formation; several other patterns exist, including papillary, trabecular, or solid growth, with a multitude of additional variants described.…”

A population-based competing risk survival analysis of patients with salivary duct carcinoma

“…Some other factors such as increasing numbers of positive lymph nodes, lymph node ratio (LNR), lymph-vascular invasion, perineural invasion and HER2/neu receptor expression were also shown to influence the prognosis of SDC (8,13,14). However, due to the rarity of this disease, most of those studies focused on single-center studies with limited sample size (1,12,15,16). Therefore, the prognostic factors for SDC still remain to be largely elucidated.…”

“…Salivary duct carcinoma (SDC) is a rare salivary gland malignancy, accounting for 35% of the salivary gland malignancies (1). SDC commonly occurs in the parotid gland and submandibular or minor salivary glands, among which the parotid gland is the most frequently involved site (2,3).…”