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Gallbladder splenosis: a hereto unreported mimicker of a gallbladder neoplasm
Clinical Imaging 39 (2015) 318–320
Contents lists available at ScienceDirect
Clinical Imaging journal homepage: http://www.clinicalimaging.org
Gallbladder splenosis: a hereto unreported mimicker of a gallbladder neoplasm Leo L. Tsai ⁎, Krithica Kaliannan, Koenraad J. Mortele Division of Body MRI, Department of Radiology, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA 02215
a r t i c l e
i n f o
Article history: Received 27 August 2014 Received in revised form 27 October 2014 Accepted 29 October 2014 Keywords: Splenosis Splenectomy Spleen Gallbladder
a b s t r a c t Splenosis is a completely benign entity that can mimic a primary mass or metastasis. Herein we report the first known case of gallbladder splenosis in a 49-year-old woman with an extensive surgical and medical history. Cross-sectional computed tomography and MRI demonstrated a single mass arising from the gallbladder fundus. Revelation of splenectomy, confirmed to be traumatic from medical records, raised the suspicion for splenosis. The diagnosis was confirmed with a Technecium-99m-labeled heat-damaged blood cell scan, considered the gold-standard for detection of ectopic splenic tissue. © 2015 Elsevier Inc. All rights reserved.
1. Introduction Splenosis refers to the heterotopic autotransplantation of splenic tissue, typically from trauma or surgery, initially described in 1939 [1]. Implantation of splenic tissue can occur anywhere in the body, including the liver, kidneys, ovaries, thorax, and brain [2–5] and, though a completely benign process, can mimic a primary mass or metastasis. Here, we report the first known case of gallbladder splenosis in a patient with an extensive surgical and medical history.
2. Case report A 49-year-old woman presented to our institution for further evaluation of multiple episodes of small bowel obstructions. Her medical history was notable for sigmoid colon obstruction relating to prior C-section that required surgery, left oophorectomy for a mucinous cystadenofibroma, uterine fibroid embolization, and splenectomy for trauma as a child. These procedures were all performed elsewhere prior to her presentation at our institution. A computed tomography (CT) examination was performed at our emergency room during an episode of acute abdominal pain, to rule out a bowel obstruction. Both iv and oral contrast were administered. While no bowel obstruction was present, the examination was notable for an oval, well-circumscribed uniformly enhancing mass abutting the gallbladder fundus (Fig. 1). The attenuation of this lesion was indistinguishable from the adjacent hepatic parenchyma.
The patient recovered from her episode of abdominal pain and returned for an MR enterography to evaluate for any small bowel or mesenteric lesions. Precontrast images again demonstrated a mass arising from the gallbladder wall, unchanged in size, with similar signal characteristics as the liver on T2-weighted sequences (Fig. 2). However, postcontrast images showed that the enhancement pattern was significantly different from the liver, and the mass was clearly contiguous with the gallbladder fundal wall (Fig. 3). The mass also demonstrated marked restricted diffusion (Fig. 4), distinct from adjacent structures. No other lesions with the same imaging characteristics were seen within the abdomen and pelvis. The smooth appearance of the mass and lack of other abdominal and pelvic findings favored a benign entity such as a mesenchymal tumor. More common causes of focal gallbladder wall thickening such as adenomyomatosis were felt to be unlikely given the size, solid appearance, and uniform enhancement. However, given the high degree of restricted diffusion on MRI, gallbladder splenosis was suspected, as the patient reported a history of splenectomy for trauma as a child. A Technecium- 99m-labeled heat-damaged RBC (Tc99m-HDRBC) scan was performed and confirmed this diagnosis, with avid tracer uptake demonstrated only within this mass (Fig. 5). The surgeon or gastroenterologist therefore did not recommend biopsy or surgical excision. Since imaging did not reveal any discrete mass directly related to her bowel obstructions, the patient elected for conservative management of her symptoms.
3. Discussion ⁎ Corresponding author. Division of Body MRI, Department of Radiology, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA 02215. Tel.: +1-617-6670278; fax: +1-617-667-7917. E-mail address: [email protected] (L.L. Tsai). http://dx.doi.org/10.1016/j.clinimag.2014.10.018 0899-7071/© 2015 Elsevier Inc. All rights reserved.
In cases of splenic rupture, typically from trauma, splenosis occurs from direct seeding, with the splenic pulp recruiting vascular supply from abutting stroma. Most cases of splenosis thus occur within the
L.L. Tsai et al. / Clinical Imaging 39 (2015) 318–320
319
Fig. 1. Coronal reconstruction from postcontrast CT examination shows a rounded mass abutting the inferior aspect of the right hepatic lobe and the gallbladder fundus (arrow), with similar density as the liver parenchyma.
Fig. 3. Coronal postcontrast T1-weighted MR image with a breath-hold 3D gradient echo sequence shows hypervascularity of the mass relative to the hepatic parenchyma. In addition, the mass is now clearly contiguous with the gallbladder fundus wall which is slightly thickened (arrow).
left upper quadrant of the abdomen, particularly along the gastrosplenic and splenopancreatic ligaments. Direct implantation against the pancreatic tail can mimic a hypervascular mass such as a neuroendocrine tumor; splenosis should therefore be considered when a pancreatic tail lesion is detected in a postsplenectomy patient [6]. Hematogenous spread is believed to occur in cases of splenosis where direct seeding is either highly unlikely or physically impossible, such as in the thorax or the brain [4]. Imaging characteristics for splenosis are identical to that of native splenic tissue; it is often the atypical location or lack of a comparative native spleen that hinders definitive diagnosis. There is a very limited role for ultrasound in splenosis as imaging characteristics are nonspecific, with lesions often appearing as a mass with uniform echogenicity, either hyper- or hypoechoic depending on the surrounding tissue [7]. The typical splenosis implant measures about 1 cm and can demonstrate mild hypertrophy over time. On CT, splenosis demonstrates similar characteristics as native splenic tissue: typically slightly hypodense on noncontrast images and equilibrium-phase postcontrast images and hyperdense on early-phase postcontrast images relative to the liver, though postcontrast density can be variable depending on the rate of
injection and length of acquisition delay [8,9]. Due to their small size, splenosis implants typically exhibit a uniform enhancement pattern in comparison to bulk native splenic tissue, which can display differential enhancement across white and red pulp on early-phase images. On MRI, splenic tissue usually appears hypointense on T1-weighted images and hyperintense on T2-weighted images relative to the liver, with heterogeneous enhancement on earlier phase dynamic sequences, and homogeneous enhancement on delayed sequences [10]. As with the case of the native spleen, abnormal iron deposition can cause the splenic tissue to be hypointense on T2-weighted sequences. On diffusionweighted images, splenic tissue usually demonstrates substantially lower apparent diffusion coefficient (ADC) values relative to other abdominal organs [11,12] and is therefore often highlighted on traceweighted images with high b-values, as demonstrated in this case. Scintigraphy offers the most sensitive and specific imaging tests for splenosis. Tc99m-labeled sulfur colloid is still commonly used, as it is technically easy to prepare and administer, but false negatives, particularly for small lesions, can occur, as background absorption from the liver is relatively high. A Tc 99m-HDRBC is far more sensitive and specific, as over 90% of introduced damaged red blood cells are absorbed by splenic tissue, in contrast to only 10% of injected sulfur colloid [13,14]. A positive Tc99mHDRBC study is considered the gold standard for detection of splenic tissue and usually precludes the need for any additional testing or biopsy. The differential diagnoses for splenosis include accessory spleen, polysplenia, metastases or primary tumors, and atypical infections. In cases of solitary splenosis, a primary tumor or metastasis is often suspected, particularly at sites away from the left upper quadrant. Ectopic splenic tissue is highly vascular, can exhibit mass effect, and demonstrates restricted diffusion on MRI. Multifocal splenosis throughout the abdominal cavity can have the same radiologic appearance as diffuse carcinomatosis [15,16]. Atypical infections, such as tuberculosis, can also demonstrate plaque-like masses but are usually more easily differentiated from splenosis by medical history and symptoms. Accessory spleens are congenital foci of splenic tissue separate from the main spleen, arising from incomplete fusion during embryological development [17]. In contrast to splenosis, accessory spleens are very common. Because of their congenital origin, they derive their vascular supply exclusively from the splenic artery and are thus only found in the vicinity of the main splenic body. Polysplenia occurs under a spectrum of left-sided isomerism, typically manifesting as multiple splenic nodules without a distinctive main splenic body. This diagnosis is typically easy to make on cross-sectional imaging, as there is usually an associated anatomical anomaly involving the lungs, bowel, liver, or inferior vena cava [18].
Fig. 2. Coronal T2-weighted precontrast steady-state free precession MR sequence shows the mass again abutting the gallbladder fundus and inferior liver (arrow). The signal intensity of the mass is not visually different from the hepatic parenchyma, nor was it significantly different when measured quantitatively with a region of interest tool.
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L.L. Tsai et al. / Clinical Imaging 39 (2015) 318–320
Fig. 4. Axial diffusion-weighted MRI trace image (a) at b=600 shows the mass with very high signal intensity (arrow), with confirmed relative restriction on ADC map (b).
Solid exophytic gallbladder masses are very rare, as the most common lesions, such as polyps, are typically intraluminal [19]. Benign solid primary wall and stromal masses include leiomyomas, hemangiomas, and lipomas. Focal adenomyomatosis may mimic a solid mass if there is lack of fluid filling within the intramuscular diverticula or increased associated smooth muscle proliferation [20]. Xanthogranulomatous cholecystits could result in focal wall thickening, but this would be expected in the setting of chronic cholecystitis, and lesions tend to be heterogenous and ill-defined on ultrasound and CT [21]. Gallbladder carcinoma typically manifests as irregular wall thickening with involvement of the adjacent liver parenchyma or bile ducts; however, small early masses can appear as smooth focal wall thickening [22]. This represents the first known case of gallbladder splenosis in a patient with a remote history of traumatic splenectomy. The diagnosis of splenosis can often be difficult as splenic implants can often have the appearance of primary tumors or metastasis anywhere in the body, and patients often no longer have a native spleen for comparison. Nevertheless, splenosis should be considered in the differential diagnosis for a newly detected mass whenever a history of either splenic injury or splenectomy is known. As shown in this case, definitive diagnosis can be made noninvasively with a Tc99m-HDRBC scan, avoiding biopsy or surgical excision.
Fig. 5. Scintigraphic projection from a Tc99m-HDRBC scan shows marked uptake of tracer by this mass, diagnostic for splenic tissue. There is mild background hepatic uptake.
References [1] Buchbinder JH, Lipkoff CJ. Splenosis: multiple peritoneal splenic implants following abdominal injury. Surgery 1939;6(6):927–34. [2] Inchingolo R, Peddu P, Karani J. Hepatic splenosis presenting as arterialised liver lesion in a patient with NASH. Eur Rev Med Pharmacol Sci 2013;17(21):2853–6. [3] Metindir J, Mersin HH, Bulut MZ. Pelvic splenosis mimicking ovarian metastasis of breast carcinoma: a case report. J Turk Ger Gynecol Assoc 2011;12(2):130–2. [4] Rickert CH, Maasjosthusmann U, Probst-Cousin S, August C, Gullotta F. A unique case of cerebral spleen. Am J Surg Pathol 1998;22(7):894–6. [5] Segev Y, Lavie O, Goldberg Y, Kaufman Y, Peerl G, Gips S, Eizenberg D, Auslander R. Pelvic splenosis mimicking an ovarian mass: a non-invasive approach. Isr Med Assoc J 2007;9(11):819–20. [6] Fiamingo P, Veroux M, Da Rold A, Guerriero S, Pariset S, Buffone A, Tedeschi U. A rare diagnosis for a pancreatic mass: splenosis. J Gastrointest Surg 2004;8(7):915–6. [7] Delamarre J, Capron JP, Drouard F, Joly JP, Deschepper B, Carton S. Splenosis: ultrasound and CT findings in a case complicated by an intraperitoneal implant traumatic hematoma. Gastrointest Radiol 1988;13(3):275–8. [8] Freeman JL, Jafri SZ, Roberts JL, Mezwa DG, Shirkhoda A. CT of congenital and acquired abnormalities of the spleen. Radiographics 1993;13(3):597–610. [9] Tsitouridis I, Michaelides M, Sotiriadis C, Arvaniti M. CT and MRI of intraperitoneal splenosis. Diagn Interv Radiol 2010;16(2):145–9. [10] Lin W-C, Lee R-C, Chiang J-H, Wei C-J, Chu L-S, Liu R-S, et al. MR features of abdominal splenosis. Am J Roentgenol 2003;180(2):493–6. [11] Rosenkrantz AB, Oei M, Babb JS, Niver BE, Taouli B. Diffusion-weighted imaging of the abdomen at 3.0 Tesla: image quality and apparent diffusion coefficient reproducibility compared with 1.5 Tesla. J Magn Reson Imaging 2011;33(1):128–35. [12] Yoshikawa T, Kawamitsu H, Mitchell DG, Ohno Y, Ku Y, Seo Y, Fujii M, Sugimura K. ADC measurement of abdominal organs and lesions using parallel imaging technique. Am J Roentgenol 2006;187(6):1521–30. [13] Gunes I, Yilmazlar T, Sarikaya I, Akbunar T, Irgil C. Scintigraphic detection of splenosis: superiority of tomographic selective spleen scintigraphy. Clin Radiol 1994;49(2):115–7. [14] Bidet AC, Dreyfus-Schmidt G, Mas J, Combe J, Milleret P, Bidet R. Diagnosis of splenosis: the advantages of splenic scintiscanning with Tc 99m heat-damaged red blood cells. Eur J Nucl Med 1986;12(7):357–8. [15] Kellert B, Caster M, Des Jean R, Vaccarello L. Diffuse intra-abdominal splenosis presenting as carcinomatosis exhibiting positron emitted tomography hypermetabolic activity. Gynecol Oncol Case Rep 2013;5:46–8. [16] Short NJ, Hayes TG, Bhargava P. Intra-abdominal splenosis mimicking metastatic cancer. Am J Med Sci 2011;341(3):246–9. [17] Mortelé KJ, Mortelé B, Silverman SG. CT features of the accessory spleen. Am J Roentgenol 2004;183(6):1653–7. [18] Winer-Muram HT, Tonkin IL. The spectrum of heterotaxic syndromes. Radiol Clin North Am 1989;27(6):1147–70. [19] Levy AD, Murakata LA, Abbott RM, Rohrmann CA. From the archives of the AFIP. Benign tumors and tumorlike lesions of the gallbladder and extrahepatic bile ducts: radiologic-pathologic correlation. Armed Forces Institute of Pathology. Radiographics 2002;22(2):387–413. [20] Ching BH, Yeh BM, Westphalen AC, Joe BN, Qayyum A, Coakley FV. CT differentiation of adenomyomatosis and gallbladder cancer. Am J Roentgenol 2007;189(1):62–6. [21] Parra JA, Acinas O, Bueno J, Guezmes A, Fernandez MA, Farinas MC. Xanthogranulomatous cholecystitis: clinical, sonographic, and CT findings in 26 patients. Am J Roentgenol 2000;174(4):979–83. [22] Rooholamini SA, Tehrani NS, Razavi MK, Au AH, Hansen GC, Ostrzega N, Verma RC. Imaging of gallbladder carcinoma. Radiographics 1994;14(2):291–306.
Contents lists available at ScienceDirect
Clinical Imaging journal homepage: http://www.clinicalimaging.org
Gallbladder splenosis: a hereto unreported mimicker of a gallbladder neoplasm Leo L. Tsai ⁎, Krithica Kaliannan, Koenraad J. Mortele Division of Body MRI, Department of Radiology, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA 02215
a r t i c l e
i n f o
Article history: Received 27 August 2014 Received in revised form 27 October 2014 Accepted 29 October 2014 Keywords: Splenosis Splenectomy Spleen Gallbladder
a b s t r a c t Splenosis is a completely benign entity that can mimic a primary mass or metastasis. Herein we report the first known case of gallbladder splenosis in a 49-year-old woman with an extensive surgical and medical history. Cross-sectional computed tomography and MRI demonstrated a single mass arising from the gallbladder fundus. Revelation of splenectomy, confirmed to be traumatic from medical records, raised the suspicion for splenosis. The diagnosis was confirmed with a Technecium-99m-labeled heat-damaged blood cell scan, considered the gold-standard for detection of ectopic splenic tissue. © 2015 Elsevier Inc. All rights reserved.
1. Introduction Splenosis refers to the heterotopic autotransplantation of splenic tissue, typically from trauma or surgery, initially described in 1939 [1]. Implantation of splenic tissue can occur anywhere in the body, including the liver, kidneys, ovaries, thorax, and brain [2–5] and, though a completely benign process, can mimic a primary mass or metastasis. Here, we report the first known case of gallbladder splenosis in a patient with an extensive surgical and medical history.
2. Case report A 49-year-old woman presented to our institution for further evaluation of multiple episodes of small bowel obstructions. Her medical history was notable for sigmoid colon obstruction relating to prior C-section that required surgery, left oophorectomy for a mucinous cystadenofibroma, uterine fibroid embolization, and splenectomy for trauma as a child. These procedures were all performed elsewhere prior to her presentation at our institution. A computed tomography (CT) examination was performed at our emergency room during an episode of acute abdominal pain, to rule out a bowel obstruction. Both iv and oral contrast were administered. While no bowel obstruction was present, the examination was notable for an oval, well-circumscribed uniformly enhancing mass abutting the gallbladder fundus (Fig. 1). The attenuation of this lesion was indistinguishable from the adjacent hepatic parenchyma.
The patient recovered from her episode of abdominal pain and returned for an MR enterography to evaluate for any small bowel or mesenteric lesions. Precontrast images again demonstrated a mass arising from the gallbladder wall, unchanged in size, with similar signal characteristics as the liver on T2-weighted sequences (Fig. 2). However, postcontrast images showed that the enhancement pattern was significantly different from the liver, and the mass was clearly contiguous with the gallbladder fundal wall (Fig. 3). The mass also demonstrated marked restricted diffusion (Fig. 4), distinct from adjacent structures. No other lesions with the same imaging characteristics were seen within the abdomen and pelvis. The smooth appearance of the mass and lack of other abdominal and pelvic findings favored a benign entity such as a mesenchymal tumor. More common causes of focal gallbladder wall thickening such as adenomyomatosis were felt to be unlikely given the size, solid appearance, and uniform enhancement. However, given the high degree of restricted diffusion on MRI, gallbladder splenosis was suspected, as the patient reported a history of splenectomy for trauma as a child. A Technecium- 99m-labeled heat-damaged RBC (Tc99m-HDRBC) scan was performed and confirmed this diagnosis, with avid tracer uptake demonstrated only within this mass (Fig. 5). The surgeon or gastroenterologist therefore did not recommend biopsy or surgical excision. Since imaging did not reveal any discrete mass directly related to her bowel obstructions, the patient elected for conservative management of her symptoms.
3. Discussion ⁎ Corresponding author. Division of Body MRI, Department of Radiology, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA 02215. Tel.: +1-617-6670278; fax: +1-617-667-7917. E-mail address: [email protected] (L.L. Tsai). http://dx.doi.org/10.1016/j.clinimag.2014.10.018 0899-7071/© 2015 Elsevier Inc. All rights reserved.
In cases of splenic rupture, typically from trauma, splenosis occurs from direct seeding, with the splenic pulp recruiting vascular supply from abutting stroma. Most cases of splenosis thus occur within the
L.L. Tsai et al. / Clinical Imaging 39 (2015) 318–320
319
Fig. 1. Coronal reconstruction from postcontrast CT examination shows a rounded mass abutting the inferior aspect of the right hepatic lobe and the gallbladder fundus (arrow), with similar density as the liver parenchyma.
Fig. 3. Coronal postcontrast T1-weighted MR image with a breath-hold 3D gradient echo sequence shows hypervascularity of the mass relative to the hepatic parenchyma. In addition, the mass is now clearly contiguous with the gallbladder fundus wall which is slightly thickened (arrow).
left upper quadrant of the abdomen, particularly along the gastrosplenic and splenopancreatic ligaments. Direct implantation against the pancreatic tail can mimic a hypervascular mass such as a neuroendocrine tumor; splenosis should therefore be considered when a pancreatic tail lesion is detected in a postsplenectomy patient [6]. Hematogenous spread is believed to occur in cases of splenosis where direct seeding is either highly unlikely or physically impossible, such as in the thorax or the brain [4]. Imaging characteristics for splenosis are identical to that of native splenic tissue; it is often the atypical location or lack of a comparative native spleen that hinders definitive diagnosis. There is a very limited role for ultrasound in splenosis as imaging characteristics are nonspecific, with lesions often appearing as a mass with uniform echogenicity, either hyper- or hypoechoic depending on the surrounding tissue [7]. The typical splenosis implant measures about 1 cm and can demonstrate mild hypertrophy over time. On CT, splenosis demonstrates similar characteristics as native splenic tissue: typically slightly hypodense on noncontrast images and equilibrium-phase postcontrast images and hyperdense on early-phase postcontrast images relative to the liver, though postcontrast density can be variable depending on the rate of
injection and length of acquisition delay [8,9]. Due to their small size, splenosis implants typically exhibit a uniform enhancement pattern in comparison to bulk native splenic tissue, which can display differential enhancement across white and red pulp on early-phase images. On MRI, splenic tissue usually appears hypointense on T1-weighted images and hyperintense on T2-weighted images relative to the liver, with heterogeneous enhancement on earlier phase dynamic sequences, and homogeneous enhancement on delayed sequences [10]. As with the case of the native spleen, abnormal iron deposition can cause the splenic tissue to be hypointense on T2-weighted sequences. On diffusionweighted images, splenic tissue usually demonstrates substantially lower apparent diffusion coefficient (ADC) values relative to other abdominal organs [11,12] and is therefore often highlighted on traceweighted images with high b-values, as demonstrated in this case. Scintigraphy offers the most sensitive and specific imaging tests for splenosis. Tc99m-labeled sulfur colloid is still commonly used, as it is technically easy to prepare and administer, but false negatives, particularly for small lesions, can occur, as background absorption from the liver is relatively high. A Tc 99m-HDRBC is far more sensitive and specific, as over 90% of introduced damaged red blood cells are absorbed by splenic tissue, in contrast to only 10% of injected sulfur colloid [13,14]. A positive Tc99mHDRBC study is considered the gold standard for detection of splenic tissue and usually precludes the need for any additional testing or biopsy. The differential diagnoses for splenosis include accessory spleen, polysplenia, metastases or primary tumors, and atypical infections. In cases of solitary splenosis, a primary tumor or metastasis is often suspected, particularly at sites away from the left upper quadrant. Ectopic splenic tissue is highly vascular, can exhibit mass effect, and demonstrates restricted diffusion on MRI. Multifocal splenosis throughout the abdominal cavity can have the same radiologic appearance as diffuse carcinomatosis [15,16]. Atypical infections, such as tuberculosis, can also demonstrate plaque-like masses but are usually more easily differentiated from splenosis by medical history and symptoms. Accessory spleens are congenital foci of splenic tissue separate from the main spleen, arising from incomplete fusion during embryological development [17]. In contrast to splenosis, accessory spleens are very common. Because of their congenital origin, they derive their vascular supply exclusively from the splenic artery and are thus only found in the vicinity of the main splenic body. Polysplenia occurs under a spectrum of left-sided isomerism, typically manifesting as multiple splenic nodules without a distinctive main splenic body. This diagnosis is typically easy to make on cross-sectional imaging, as there is usually an associated anatomical anomaly involving the lungs, bowel, liver, or inferior vena cava [18].
Fig. 2. Coronal T2-weighted precontrast steady-state free precession MR sequence shows the mass again abutting the gallbladder fundus and inferior liver (arrow). The signal intensity of the mass is not visually different from the hepatic parenchyma, nor was it significantly different when measured quantitatively with a region of interest tool.
320
L.L. Tsai et al. / Clinical Imaging 39 (2015) 318–320
Fig. 4. Axial diffusion-weighted MRI trace image (a) at b=600 shows the mass with very high signal intensity (arrow), with confirmed relative restriction on ADC map (b).
Solid exophytic gallbladder masses are very rare, as the most common lesions, such as polyps, are typically intraluminal [19]. Benign solid primary wall and stromal masses include leiomyomas, hemangiomas, and lipomas. Focal adenomyomatosis may mimic a solid mass if there is lack of fluid filling within the intramuscular diverticula or increased associated smooth muscle proliferation [20]. Xanthogranulomatous cholecystits could result in focal wall thickening, but this would be expected in the setting of chronic cholecystitis, and lesions tend to be heterogenous and ill-defined on ultrasound and CT [21]. Gallbladder carcinoma typically manifests as irregular wall thickening with involvement of the adjacent liver parenchyma or bile ducts; however, small early masses can appear as smooth focal wall thickening [22]. This represents the first known case of gallbladder splenosis in a patient with a remote history of traumatic splenectomy. The diagnosis of splenosis can often be difficult as splenic implants can often have the appearance of primary tumors or metastasis anywhere in the body, and patients often no longer have a native spleen for comparison. Nevertheless, splenosis should be considered in the differential diagnosis for a newly detected mass whenever a history of either splenic injury or splenectomy is known. As shown in this case, definitive diagnosis can be made noninvasively with a Tc99m-HDRBC scan, avoiding biopsy or surgical excision.
Fig. 5. Scintigraphic projection from a Tc99m-HDRBC scan shows marked uptake of tracer by this mass, diagnostic for splenic tissue. There is mild background hepatic uptake.
References [1] Buchbinder JH, Lipkoff CJ. Splenosis: multiple peritoneal splenic implants following abdominal injury. Surgery 1939;6(6):927–34. [2] Inchingolo R, Peddu P, Karani J. Hepatic splenosis presenting as arterialised liver lesion in a patient with NASH. Eur Rev Med Pharmacol Sci 2013;17(21):2853–6. [3] Metindir J, Mersin HH, Bulut MZ. Pelvic splenosis mimicking ovarian metastasis of breast carcinoma: a case report. J Turk Ger Gynecol Assoc 2011;12(2):130–2. [4] Rickert CH, Maasjosthusmann U, Probst-Cousin S, August C, Gullotta F. A unique case of cerebral spleen. Am J Surg Pathol 1998;22(7):894–6. [5] Segev Y, Lavie O, Goldberg Y, Kaufman Y, Peerl G, Gips S, Eizenberg D, Auslander R. Pelvic splenosis mimicking an ovarian mass: a non-invasive approach. Isr Med Assoc J 2007;9(11):819–20. [6] Fiamingo P, Veroux M, Da Rold A, Guerriero S, Pariset S, Buffone A, Tedeschi U. A rare diagnosis for a pancreatic mass: splenosis. J Gastrointest Surg 2004;8(7):915–6. [7] Delamarre J, Capron JP, Drouard F, Joly JP, Deschepper B, Carton S. Splenosis: ultrasound and CT findings in a case complicated by an intraperitoneal implant traumatic hematoma. Gastrointest Radiol 1988;13(3):275–8. [8] Freeman JL, Jafri SZ, Roberts JL, Mezwa DG, Shirkhoda A. CT of congenital and acquired abnormalities of the spleen. Radiographics 1993;13(3):597–610. [9] Tsitouridis I, Michaelides M, Sotiriadis C, Arvaniti M. CT and MRI of intraperitoneal splenosis. Diagn Interv Radiol 2010;16(2):145–9. [10] Lin W-C, Lee R-C, Chiang J-H, Wei C-J, Chu L-S, Liu R-S, et al. MR features of abdominal splenosis. Am J Roentgenol 2003;180(2):493–6. [11] Rosenkrantz AB, Oei M, Babb JS, Niver BE, Taouli B. Diffusion-weighted imaging of the abdomen at 3.0 Tesla: image quality and apparent diffusion coefficient reproducibility compared with 1.5 Tesla. J Magn Reson Imaging 2011;33(1):128–35. [12] Yoshikawa T, Kawamitsu H, Mitchell DG, Ohno Y, Ku Y, Seo Y, Fujii M, Sugimura K. ADC measurement of abdominal organs and lesions using parallel imaging technique. Am J Roentgenol 2006;187(6):1521–30. [13] Gunes I, Yilmazlar T, Sarikaya I, Akbunar T, Irgil C. Scintigraphic detection of splenosis: superiority of tomographic selective spleen scintigraphy. Clin Radiol 1994;49(2):115–7. [14] Bidet AC, Dreyfus-Schmidt G, Mas J, Combe J, Milleret P, Bidet R. Diagnosis of splenosis: the advantages of splenic scintiscanning with Tc 99m heat-damaged red blood cells. Eur J Nucl Med 1986;12(7):357–8. [15] Kellert B, Caster M, Des Jean R, Vaccarello L. Diffuse intra-abdominal splenosis presenting as carcinomatosis exhibiting positron emitted tomography hypermetabolic activity. Gynecol Oncol Case Rep 2013;5:46–8. [16] Short NJ, Hayes TG, Bhargava P. Intra-abdominal splenosis mimicking metastatic cancer. Am J Med Sci 2011;341(3):246–9. [17] Mortelé KJ, Mortelé B, Silverman SG. CT features of the accessory spleen. Am J Roentgenol 2004;183(6):1653–7. [18] Winer-Muram HT, Tonkin IL. The spectrum of heterotaxic syndromes. Radiol Clin North Am 1989;27(6):1147–70. [19] Levy AD, Murakata LA, Abbott RM, Rohrmann CA. From the archives of the AFIP. Benign tumors and tumorlike lesions of the gallbladder and extrahepatic bile ducts: radiologic-pathologic correlation. Armed Forces Institute of Pathology. Radiographics 2002;22(2):387–413. [20] Ching BH, Yeh BM, Westphalen AC, Joe BN, Qayyum A, Coakley FV. CT differentiation of adenomyomatosis and gallbladder cancer. Am J Roentgenol 2007;189(1):62–6. [21] Parra JA, Acinas O, Bueno J, Guezmes A, Fernandez MA, Farinas MC. Xanthogranulomatous cholecystitis: clinical, sonographic, and CT findings in 26 patients. Am J Roentgenol 2000;174(4):979–83. [22] Rooholamini SA, Tehrani NS, Razavi MK, Au AH, Hansen GC, Ostrzega N, Verma RC. Imaging of gallbladder carcinoma. Radiographics 1994;14(2):291–306.