S1417 Painless Jaundice: A Case of Primary Pure Squamous Cell Carcinoma of the Gallbladder

Abstract

INTRODUCTION: Gallbladder cancer is the most common malignant tumor of the biliary tract with the majority of cases are adenocarcinoma (AC). Pure squamous cell carcinoma (SCC) of the gallbladder (GB) is extremely rare and accounts for only around 0.5 - 3% of all GB cancers. The initial presentation of these cases varies significantly due to its rarity. We, therefore, present a case of painless jaundice due to SCC of the gallbladder. CASE DESCRIPTION/METHODS: The patient is a 78-year-old man who presented with a 3-day history of painless jaundice. Accompanied by dark urine and clay-colored stools. He denied notable weight loss, night sweats, nausea, or vomiting. Hepatic function panel was significant for ALT 686, AST 483, Alkaline Phosphatase 1183, total bilirubin 25.6, and direct bilirubin 20.6. MRCP revealed intrahepatic biliary dilatation, a 7 mm cystic structure at the level of the head of the pancreas, and diffuse gallbladder thickening. ERCP was attempted, however, aborted due to distorted anatomy secondary to distorted anatomy. Endoscopic ultrasound demonstrated an irregular hypoechoic mass of 45 mm × 40 mm at the level of the gallbladder. Fine needle aspiration was consistent with squamous cell carcinoma. On further evaluation by multidisciplinary committee, it demonstrated invasion into the duodenum therefore surgical resection was not feasible decided to proceed with palliative radiation. DISCUSSION: Most of the published literature on pure SCC of the gallbladder is based on case reports and case series. SCC of the GB is thought to be due to keratinization of the columnar lining of the GB due to chronic repeated irritants, like cholelithiasis. Therefore, populations more prone to developing stones are thought to be higher in incidence, with a known female predominance. We described the rare presentation of painless jaundice in an elderly male with locally invasive SCC of the GB. The survival rates of SCC of the GB are significantly lower (mean: 5 months) compared to AC of the GB (mean survival: 11.4 months). As most of these lesions are advanced at presentation, rendering them unresectable (70–90%), resulting in poor prognoses. A standard regimen of chemotherapy for squamous-cell gallbladder cancer does not exist and, the only definite curative measure is resection. Therefore, while encountering painless jaundice it is important to consider carcinomas of the GB, as earlier detection of these cancers can open greater opportunities for curative resection.Figure 1.: Irregular malignant cells with hyperchromatic nuclei and glassy keratinizing cytoplasm positive for p63 consistent with Squamous cell carcinoma.Figure 2.: Irregular malignant cells with hyperchromatic nuclei and glassy keratinizing cytoplasm positive for p63 consistent with Squamous cell carcinoma.Figure 3.: Endoscopic Ultrasound: 45 mm × 40 mm irregular mass with poorly defined borders at the level of the gallbladder.