Epidermoid cyst within an intrapancreatic accessory spleen exhibiting abrupt changes in serum carbohydrate antigen 19-9 level: a case report
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Published on: July 26, 2024
Chisato Takagi1, Nobuo Hoshi2, Yutaro Kikuchi3
1Department of Hepato-Biliary-Pancreatic Surgery, Tochigi Cancer Center, 4-9-13, Yohnan, Utsunomiya, Tochigi, 320-0834, Japan. chtakagi@tochigi-cc.jp.
Insights
Epidermoid cyst within an intrapancreatic accessory spleen (ECIAS) is rare. Careful monitoring of serum CA 19-9 levels and MRI findings may help diagnose ECIAS without solid components, avoiding unnecessary surgery.
Area of Science:
- Gastroenterology
- Surgical Pathology
- Diagnostic Imaging
Background:
- Epidermoid cyst within an intrapancreatic accessory spleen (ECIAS) is an uncommon condition.
- Distinguishing ECIAS from malignant pancreatic tumors can be challenging without surgical resection, especially when solid components are absent.
Purpose of the Study:
- To highlight the diagnostic challenges of ECIAS.
- To explore imaging and serological markers for non-invasive ECIAS diagnosis.
Main Methods:
- A case report of a 73-year-old male with an incidentally discovered cystic pancreatic tail lesion.
- Utilized abdominal ultrasound, MRI, and serum carbohydrate antigen (CA) 19-9 monitoring.
- Surgical resection (distal pancreatectomy with splenectomy) and subsequent histopathological examination.
Main Results:
- The patient presented with fluctuating CA 19-9 levels and a multicystic pancreatic mass on MRI without solid components.
- Histopathology confirmed ECIAS with varying stages of mucinous cyst reaction and inflammation.
- The final diagnosis of ECIAS was established post-resection.
Conclusions:
- ECIAS diagnosis can be challenging due to its rarity and lack of solid components.
- Serial monitoring of CA 19-9 levels and serial MRI may aid in differentiating ECIAS from malignant lesions.
- Non-invasive diagnostic strategies are crucial for avoiding unnecessary pancreatic surgery.
Background:
Epidermoid cyst within an intrapancreatic accessory spleen (ECIAS) is a rare disease. While the detection of solid components relevant to an accessory spleen is a key diagnostic finding, the differential diagnosis between ECIAS and malignant tumors is difficult without resection in patients with no other findings of an accessory spleen.
Case Presentation:
A 73-year-old male was found to have an elevated carbohydrate antigen (CA) 19-9 level (95 U/mL) at an annual checkup, and a cystic lesion in the pancreatic tail was located by abdominal ultrasound. Abdominal magnetic resonance imaging (MRI) revealed a multicystic mass, 24 mm in diameter, which exhibited varying intensities on T2-weighted images. There were no findings suggesting solid components on contrast-enhanced computed tomography and magnetic resonance imaging. Re-evaluation of serum CA 19-9 level revealed a rapid increase to 901 U/mL, which declined to 213 U/mL 3 weeks later. Ruling out the lesion's malignant potential was difficult, and the patient underwent distal pancreatectomy with splenectomy. Histological findings revealed an ECIAS including multiple cysts, with the mucinous component of each cyst exhibiting different stages of biological reaction; one ruptured cyst exhibited inflammatory changes.
Conclusions:
Careful observation for changes in serum CA 19-9 level and MRI findings might facilitate the diagnosis of ECIAS without a solid component by imaging studies.
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Assessment:
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