Clinicopathological features and prognosis analysis of salivary duct carcinoma

Abstract

Objective To summarize the clinicopathological characteristics and prognostic factors of salivary duct carcinoma (SDC) patients. Methods This study was reviewed and approved by the Ethics Committee, and informed consent was obtained from the patients. The clinical data of 30 SDC patients who were admitted to the Fourth Hospital of Hebei Medical University from 2014 to 2022, including case records, pathological diagnoses, immunohistochemical indicators, treatment methods, follow-up data, and other data, were retrospectively analyzed. SPSS 26.0 software was used to process the data and construct relevant curves. The chi-square test was used to analyze the correlation between different immunohistochemical indices and the recurrence and metastasis of SDC, and a single factor was used to analyze clinical prognostic factors. Results Among the 30 SDC patients, the male-to-female ratio was 5∶1, with a median age of 61.5 years. Approximately 60% of cases occurred in the parotid gland, whereas the remainder occurred in the submaxillary gland, sublingual gland, or minor salivary gland. Among them, 19 patients were androgen receptor-positive, 23 patients were human epidermal growth factor receptor-2 positive, and 26 patients were Ki-67 positive. Postoperative follow-up was 18-94 months, with a median follow-up of 37 months. There were 13 cases of recurrence and 14 cases of distant metastasis. The 5-year overall survival rate was only 31.2%. The long-term survival of patients who underwent postoperative radiotherapy and chemoradiotherapy was better than that of patients who underwent surgery alone (P= 0.027). T stage and lymph node invasion were associated with prognosis and survival (P<0.05). There was a correlation between a Ki-67-positive cell count ≥ 40% and postoperative recurrence or metastasis (P = 0.025). Conclusion Radical surgery combined with postoperative radiotherapy and chemoradiotherapy is helpful for improving long-term overall survival, and tumor T stage and lymph node metastasis may be the main factors affecting the prognosis of patients with SDC. Patients with Ki-67-positive cell counts ≥ 40% are prone to postoperative recurrence or metastasis.

Keywords

• salivary duct carcinoma|ki-67|human epidermal growth factor receptor 2|androgen receptor|t stage|lymph node invasion|survival rate|prognosis