July 2019 Case

Phong Ha, MD, and Thomas Learch, MD

84 year old male with indwelling urethral catheter with blood in urinary leg bag.

• PMH: DM2, hypothyroidism, anemia, hypertension, CKD3
• Social: No tobacco or alcohol

Physical exam: unremarkable

CT abdomen/pelvis without contrast was performed.

CT largely unremarkable except: Lobulated contour of the tail of the pancreas which appears enlarged with texture different from the remainder of the pancreas.

Differntial

• Solid mass in pancreatic tail
  • Mets
  • Pancreatic neuoroendocrine tumor
  • Intrapancreatic splenule
  • 3 phase pancreas CT obtained

3 phase pancreas CT obtained

Arterial

Enhancing rounded pancreatic tail mass with similar density and enhancement as spleen on all phases.

Sulfur colloid study was next performed for confirmation.

Tc 99 sulfur colloid study

Small colloid particles linked to Tc 99 are extracted by reticuloendothelial system

Distribution: liver, spleen, bone marrow

T1/2 = 6 hrs, Photon energy = 160 kEV

Other possible nuclear medicine test for identifying ectopic splenic tissue?

Tc 99 tagged heat damaged RBC study

Possible small focus on increased activity near the splenic hilum

Focus on increased activity corresponding to the pancreatic tail mass suggestive of ectopic splenic tissue - intrapancreatic splenule.

Ectopic splenic tissue

Two categories:

• Splenosis due to autotransplantation of splenic tissue (usually after splenectomy)
• Accessory spleen: congenital foci of normal splenic tissue separate from main body of spleen

Accessory spleen:

• Structurally identical to spleen
• Arises from failure of fusion on splenic tissue during 5th week of fetal life.
• 10-30% of cases in postmortem study
• Location varies: splenic hilum, pancreatic tail, greater omentum, intestinal mesentery, adnexa, scrotum

Usually pose no clinical problems and treatment is not necessary

What problems can arise?

• Can mimic lymphadenopathy or tumors.
• Torsion, spontaneous rupture, hemorrhage.

• Kim SH, Lee JM, Han JK, et al. Intrapancreatic accessory spleen: findings on MR Imaging, CT, US and scintigraphy, and the pathologic analysis. Korean J Radiol. 2008;9(2):162–174. doi:10.3348/kjr.2008.9.2.162.