Striated Duct Adenoma: A Case Report and a Scoping Review

Area of Science:

• Oncology
• Pathology
• Genetics

Background:

• Striated duct adenoma (SDA) is a rare benign salivary gland tumor.
• SDA possesses a distinct genetic signature involving IDH2 gene mutations.
• These mutations differentiate SDA from canalicular adenoma, its main differential diagnosis.

Purpose of the Study:

• To report a case of parotid gland SDA with IDH1/2 mutation-specific immunohistochemistry.
• To conduct a scoping review synthesizing all previously published SDA cases.
• To analyze the clinicopathological features and outcomes of SDA.

Main Methods:

• Case report of SDA with immunohistochemical analysis for IDH1/2 mutations.
• Scoping review following Cochrane Methodology and JBI checklist.
• Systematic literature search across Medline, Embase, Web of Science, and LILACS without date or language restrictions.

Main Results:

• Seven studies comprising 20 SDA patients (including the reported case) were analyzed.
• SDA predominantly affects the parotid gland (13/20) in individuals aged ~62 years, with no sex predilection.
• Swelling was the primary clinical symptom; mean follow-up of 26 months showed no recurrence or metastasis post-resection.

Conclusions:

• Clinicopathological awareness and IDH1/2 mutation-specific immunohistochemistry are crucial for accurate SDA identification.
• Further follow-up is necessary to fully understand the biological potential of SDA.
• Consistent identification is key for appropriate patient management and prognosis.