Abstract
Gallbladder torsion is rare and can mimic acute cholecystitis. We report an 83-year-old female who presented with abdominal pain, leukocytosis, and hyperbilirubinemia. Work-up showed a distended, thick-walled gallbladder with stones and suspected choledocholithiasis. Because of worsening pain and concern for impending perforation, she underwent urgent cholecystectomy, which revealed a freely mobile gallbladder consistent with torsion. Final pathology showed a 0.4 cm poorly differentiated adenocarcinoma with metastatic involvement of a cystic duct lymph node (stage IIIB). Postoperatively, she underwent endoscopic retrograde cholangiopancreatography and removal of a retained common bile duct stone. Staging positron emission tomography/computed tomography demonstrated no residual or metastatic disease. Because the gallbladder was detached from the liver bed due to torsion, no further hepatic resection was performed, and systemic chemotherapy was recommended. This case illustrates both the diagnostic challenge of gallbladder torsion and a novel management consideration for incidentally discovered gallbladder cancer in the setting of a floating gallbladder.
Introduction
Gallbladder torsion is a rare pathology with estimated incidence of 1 in 365 000 cases [1]. First described by Wendel in 1898 as a ‘floating gallbladder,’ it predominantly affects elderly women, with 4:1 female-to-male ratio and median age of 77 years [1]. Torsion occurs in either direction and is classified as incomplete (≤180°) or complete (>180°) [2]. While its exact etiology remains uncertain, proposed factors include anatomic variants causing mesenteric redundancy, visceroptosis, or an unattached, free-floating gallbladder [3]. Diagnosis is challenging as presentation mimics acute cholecystitis with nonspecific imaging findings. We report a case of gallbladder torsion presenting as acute cholecystitis with incidentally discovered stage IIIB gallbladder adenocarcinoma on pathology.
Case report
An 83-year-old female with history of multiple hernia repairs and rectal prolapse repair presented with two days of right upper quadrant pain and nausea. She was afebrile with normal vital signs and right upper quadrant tenderness with a positive Murphy’s sign. Initial labs demonstrated leukocytosis to 16 600/mcL and isolated hyperbilirubinemia to 1.6 mg/dl.
Computed tomography (CT) abdomen/pelvis with IV contrast demonstrated a severely dilated, thick-walled gallbladder with calculi extending to the iliac crest with associated fat stranding, consistent with acute cholecystitis (Fig. 1). Multiple incidental hepatic cysts were identified, the largest measuring 8.4 cm in the left hepatic lobe (Fig. 2).
Axial (a) and coronal (b) CT images of the abdomen and pelvis with IV contrast demonstrating a severely dilated, thick-walled gallbladder with calculi and surrounding fat stranding.
Axial CT image with the largest of several incidental hepatic cysts, measuring 8.4 cm in diameter.
She underwent magnetic resonance cholangiopancreatography (MRCP), demonstrating mild intra- and extrahepatic biliary ductal dilation with a 7 mm common bile duct (CBD) and distal filling defect consistent with choledocholithiasis. Given worsening pain, focal peritonitis, and concern for impending perforation, she underwent urgent cholecystectomy. Preoperative endoscopic retrograde cholangiopancreatography (ERCP) was deferred.
In the operating room, a diagnostic laparoscopy was performed via supraumbilical open cutdown. The wall of the gallbladder was ischemic-appearing with portal structures covered in omental adhesions. The case was converted to open given the gallbladder’s size and location. The left hepatic cyst was obstructing visualization, requiring fenestration. Diffuse gallbladder ischemia was confirmed on opening (Fig. 3). The gallbladder was torsed counterclockwise around its hilum (Fig. 4). Detorsion was performed by rotating the hilum clockwise two half-turns (360 degrees), after which the cystic artery immediately regained visible pulsatility. Open cholecystectomy was completed in standard fashion. An elongated cystic duct of 7 cm was visualized entering the CBD distally (Fig. 5), with associated fatty tissue dissected separately (Fig. 6). CBD exploration was not performed.
Diffusely ischemic gallbladder with patchy necrosis visualized upon opening.
Counterclockwise torsion of floating gallbladder around the critical structures.
Elongated 7-cm cystic duct entering the distal CBD.
Ex vivo specimen demonstrating the elongated cystic duct with surrounding periductal fatty tissue containing the cystic duct lymph node.
The postoperative course was uneventful. Total bilirubin remained elevated at 2.0 mg/dl on postoperative day (POD) one. Gastroenterology performed an ERCP on POD two with sphincterotomy and balloon extraction of two retained CBD stones. Total bilirubin normalized to 0.8 mg/dl on POD three, and the patient was discharged home.
Final pathology demonstrated acute cholecystitis and cholelithiasis with extensive necrosis and infarction in a gallbladder measuring 14 cm in length (Fig. 7). Unexpectedly, a single cystic duct lymph node was positive for metastatic adenocarcinoma without extracapsular extension (Fig. 8). This prompted additional sectioning of the entire gallbladder, revealing a 0.4 cm focus of invasive, poorly differentiated adenocarcinoma invading through the muscular wall, and into but not through perimuscular connective tissue on the peritoneal side, against a background of extensive hemorrhagic infarction with a negative surgical (cystic duct) margin (Figs 9 and 10). There was no evidence of angiolymphatic or perineural invasion. Immunohistochemistry was positive for CAM5.2 and CK7 and negative for CK20, CDX2, and TTF1, supporting biliary primary, and mismatch repair protein expression was intact. Staging positron emission tomography/computed tomography (PET/CT) demonstrated no evidence of metastatic disease. Final staging was pT2aN1 (stage IIIB). The fenestrated hepatic cyst was a benign hepatic ductal cyst.
Gross gallbladder specimen with marked acute cholecystitis with distention and dusky/necrotic serosa.
Hematoxylin and eosin-stained section of the cystic duct lymph node demonstrating metastatic adenocarcinoma (original magnification 10×).
Hematoxylin and eosin–stained section of the gallbladder wall demonstrating the focus of invasive carcinoma (lower-center of the field) in a background of extensive hemorrhagic infarction and necrosis (low-power view; original magnification 4×). The boxed area is shown at higher magnification in Fig. 10.
Higher-magnification view of the boxed region in Fig. 9, demonstrating the 0.4 cm focus of poorly differentiated adenocarcinoma with marked nuclear pleomorphism (original magnification 20×).
Discussion
We present the case of gallbladder torsion with resultant ischemia, found incidentally to harbor gallbladder adenocarcinoma on final pathology. Notably, the patient had history of bilateral inguinal hernias, umbilical hernia, and rectal prolapse, suggesting generalized tissue laxity. While floating gallbladder disposing to torsion is often congenital, acquired laxity of supporting structures in the elderly is also described, and we hypothesize this contributed here [3].
In retrospect, imaging findings were atypical for routine cholecystitis. The gallbladder was low-lying, extending to the iliac crest and separated from the liver bed, out of proportion to a typical inflammatory presentation. While she did have expected findings of wall thickening, edema, and pericholecystic stranding, the degree of distension and abnormal position should have raised suspicion for torsion. CT signs of torsion (e.g. whirl sign from twisting cystic pedicle and V-shaped distortion of the extrahepatic ducts) have been described and may aid preoperative diagnosis [4].
This patient also had an incidentally discovered cancer, identified in an unusual sequence, as the positive cystic duct node was found first. This prompted finer specimen sectioning, leading to the discovery of a T2aN1 tumor. Patients with T2 gallbladder cancer are typically indicated for segment IVb/V liver resection with portal lymphadenectomy [5]. In this patient, however, the gallbladder was suspended on a mesentery with no contact with the liver bed. There was therefore no gallbladder-hepatic interface at risk for direct parenchymal invasion. At tumor board presentation, our multidisciplinary team determined that hepatic resection had no anatomic target. In addition, the single positive cystic duct node had already been excised. Given the negative staging PET/CT and the patient’s age, the team favored adjuvant systemic therapy over completion portal lymphadenectomy. While the latter could provide additional nodal staging, it was unlikely to alter treatment strategy. She was recommended treatment with a 6-month oral capecitabine course per the BILCAP trial in resected biliary tract cancer [6]. Ultimately, the patient declined adjuvant treatment, opting for surveillance. Most recent imaging at time of publication is a one-year post-operative CT scan demonstrating no evidence of disease.
In conclusion, this case has several unusual features that led to a unique postoperative management plan: gallbladder torsion arising from a floating gallbladder, an incidentally discovered T2aN1 gallbladder adenocarcinoma, and decision to forgo segment IVb/V resection typically recommended for this stage given the absence of a hepatic interface. To our knowledge, this is the first reported case of incidentally discovered gallbladder adenocarcinoma in a floating gallbladder in which the torsion anatomy itself directed this atypical postoperative management.
Conflicts of interest
The authors declare no conflicts of interest.
Funding
This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
Consent
Written informed consent was obtained from the patient for publication of this case report and accompanying images.
