Disseminated bony metastases following incidental gallbladder cancer detected after laparoscopic cholecystectomy

Abstract

Background

In patients with gallbladder cancer bony metastases are usually a late feature.

Case outline

A 47-year-old woman presented with a 2-month history of right upper quadrant pain. Ultrasound scan showed gallstones and a thick-walled gallbladder. Laparoscopic cholecystectomy was performed. Histopathology showed poorly differentiated adenocarcinoma infiltrating the muscular layer and vascular invasion. She was referred for further surgery. Staging CT scan of the abdomen showed no local residual disease. However Tc-99 bone scan suggested disseminated bony metastases, which were confirmed by bone trephine biopsy. The cancer progressed rapidly and the patient died 4 months after the diagnosis.

Discussion

Bone metastases can occur with early gallbladder cancer and a radioisotope bone scan can avoid unnecessary extensive liver surgery.

Introduction

Gallbladder cancer is the fifth most common gastrointestinal cancer and is incidentally found in 1–2% of gallbladders after laparoscopic cholecystectomy ¹. These are usually early cancers confined to the gallbladder and adjacent liver. These early cancers are difficult to diagnose on ultrasonography ². Overall the median survival of patients with gallbladder cancer is 6 months, and the prognosis and survival depends on the stage of the disease. Potentially curative surgery gives a median survival of 3.6 years ³. Gallbladder tumours preferentially metastasise to the regional lymph nodes and liver parenchyma. Bone metastases in the early stages of gallbladder cancer have not been described. We report a patient with incidental gallbladder carcinoma following laparoscopic cholecystectomy in whom bone metastases were discovered during staging investigations prior to radical operation.

Case report

A 47-year-old woman presented with a 2-month history of intermittent right upper quadrant pain. Ultrasound scan showed a normal liver with gallstones and debris in a thick-walled gallbladder. The patient proceeded to laparoscopic cholecystectomy. An inflamed gallbladder was found with dense omental adhesions. The gallbladder was removed with a small amount of adherent liver tissue. The patient made an uneventful postoperative recovery. Two stones (<1 cm) were found in the gallbladder. Histology showed multiple foci of mucosal dysplasia and an area of poorly differentiated adenocarcinoma, which infiltrated the full thickness of the gallbladder wall (Figure 1). Vascular invasion was present (Figure 1), but no lymph nodes were identified in the specimen. She was referred for consideration of radical resection of the gallbladder bed and lymphadenectomy. CT of the abdomen showed no evidence of residual local disease and chest CT was clear of metastastic disease. However, Tc-99 methylenediphosphonate (MDP) bone scan suggested disseminated bony metastases (Figure 2), and these were confirmed by an iliac bone trephine. Clinical examination, mammography, colonoscopy and upper gastrointestinal tract endoscopy excluded other possible primary sites. Blood tests including tumour markers CA 19.9, CA 125, CA 15.3, carcinoembryogenic antigen (CEA) and alpha-fetoprotein (AFP) were all within normal limits. Two weeks after the bone scan the patient developed bony pain, which was treated by palliative radiotherapy. She deteriorated rapidly and died 6 months from the onset of the symptoms and 4 months after cholecystectomy.

Figure 1. .

Histopathology of the gallbladder showing adenocarcinoma invading the gallbladder wall.

Figure 2. .

Bone scan showing disseminated bony metastases. Metastases are demonstrated by an increased uptake of tracer (hot spots). ‘Physiological’ uptake may occur in the lumbar spine and hip joints due to degenerative disease.

Discussion

In this patient gallbladder cancer was found incidentally following laparoscopic cholecystectomy and was already associated with widespread bony metastases.

Bone metastases from gallbladder cancer are considered to be rare at the time of presentation. These cancers are usually locally invasive and disseminate transcoelomically ⁴. Historical series of patients with locally advanced gallbladder cancer did not document bony metastases ⁵,⁶. Hence bone scan is not a routine investigation for the work-up of this cancer ¹.

Laparoscopic procedures under carbon dioxide insufflation enhance tumour spread and implantation in the peritoneal cavity ⁷. In the present case metastatic disease was diagnosed within 8 weeks of the laparoscopic procedure, indicating very rapid tumour implantation and growth if the pneumoperitoneum was a factor in disease progression. However, port site and peritoneal recurrence following laparoscopic cholecystectomy for incidental gallbladder cancers has been reported as early as 3 weeks after operation, although the median time reported is 6 months ⁸,⁹,¹⁰.

The presence of undiagnosed systemic and especially bony metastases from gallbladder cancer might explain its poor prognosis despite radical surgery. Bone metastases may be more common with the introduction of laparoscopic cholecystectomy and should be excluded before radical resection is contemplated in poorly differentiated tumours with histological evidence of vascular invasion.