[Invasive micropapillary carcinoma of gallbladder: a clinicopathologic study]

Area of Science:

• Gastroenterology
• Surgical Pathology
• Oncology

Background:

• Gallbladder adenocarcinoma is a significant malignancy.
• Invasive micropapillary carcinoma (IMPC) is a distinct histological subtype with poorly understood characteristics in the gallbladder.

Purpose of the Study:

• To investigate the clinicopathologic features of gallbladder invasive micropapillary carcinoma (IMPC).
• To compare the behavior and prognosis of IMPC with conventional gallbladder adenocarcinoma.

Main Methods:

• Retrospective analysis of 160 gallbladder adenocarcinoma cases.
• Histological examination to identify IMPC components (≥5%).
• Correlation of IMPC presence with clinicopathologic parameters and survival.

Main Results:

• IMPC was detected in 19.4% of cases.
• IMPC cases showed significantly higher rates of lymph node metastasis, lymphovascular invasion, and small cluster invasion (SCI).
• IMPC was associated with poorer differentiation, advanced T stage, and significantly lower 2-year survival rates.

Conclusions:

• Gallbladder IMPC presents with more advanced tumor status and aggressive behavior compared to conventional adenocarcinoma.
• IMPC is strongly associated with lymphovascular invasion and lymph node metastasis, leading to reduced survival.
• Small cluster invasion (SCI) may play a crucial role in the invasiveness of gallbladder IMPC.