title: Rapidly progressive subcutaneous metastases from gallbladder cancer: insight into a rare presentation in gastrointestinal malignancies.
abstract: BACKGROUND
  Gallbladder cancer (GBCA) is the most common malignancy of the biliary tract. It has an aggressive biology that results in the ability to spread, seed and grow in disparate environments. It can metastasize via lymphatic, hematogenous, and peritoneal seeding. However, GBCA metastasis to distant subcutaneous sites is extremely rare.
  
  
  METHODS
  This case report describes the presentation of metastatic GBCA with rapidly progressive subcutaneous metastases. A 58-year-old woman presented with acute onset right upper quadrant abdominal pain. Computed tomography (CT) revealed a calcified and thickened gallbladder with cholelithiasis and presumed cholecystitis. Diagnostic laparoscopy revealed a gallbladder mass. Biopsies were consistent with GBCA. The patient was referred to our cancer center for further surgical management. However, she was found to have rapidly growing subcutaneous nodules in the shoulders, chest, abdomen, and buttocks. Positron emission tomography (PET) demonstrated that these were fluorodeoxyglucose (FDG)-avid. A core needle biopsy of a chest wall lesion was consistent with metastatic GBCA. Therefore, the patient was diagnosed with stage IVB GBCA and was initiated on systemic chemotherapy.
  
  
  CONCLUSIONS
  GBCA is known to have an incredible propensity to grow within the peritoneal cavity, as well as along needle biopsy tracts and at laparoscopic port sites. Several case reports have demonstrated that GBCA also has the potential to metastasize to distant subcutaneous sites, most often including breast metastases, while the current cases represents a more diffuse pattern of spread.
  
  
  CONCLUSIONS
  GBCA belongs to the short list of solid visceral malignancies that have the potential to develop remote subcutaneous metastases.
authors.affiliation: 1 Division of Medical Oncology and Department of Internal Medicine, Moores UCSD Cancer Center, 2 Department of Pathology, University of California, 3 Division of Surgical Oncology and Department of Surgery, Moores UCSD Cancer Center, University of California, San Diego, La Jolla, CA, USA.
authors.forename: Sean F
authors.initials: SF
authors.lastname: Heavey
authors.affiliation: 1 Division of Medical Oncology and Department of Internal Medicine, Moores UCSD Cancer Center, 2 Department of Pathology, University of California, 3 Division of Surgical Oncology and Department of Surgery, Moores UCSD Cancer Center, University of California, San Diego, La Jolla, CA, USA.
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Roeland
authors.affiliation: 1 Division of Medical Oncology and Department of Internal Medicine, Moores UCSD Cancer Center, 2 Department of Pathology, University of California, 3 Division of Surgical Oncology and Department of Surgery, Moores UCSD Cancer Center, University of California, San Diego, La Jolla, CA, USA.
authors.forename: Ann M Ponsford
authors.initials: AM
authors.lastname: Tipps
authors.affiliation: 1 Division of Medical Oncology and Department of Internal Medicine, Moores UCSD Cancer Center, 2 Department of Pathology, University of California, 3 Division of Surgical Oncology and Department of Surgery, Moores UCSD Cancer Center, University of California, San Diego, La Jolla, CA, USA.
authors.forename: Brian
authors.initials: B
authors.lastname: Datnow
authors.affiliation: 1 Division of Medical Oncology and Department of Internal Medicine, Moores UCSD Cancer Center, 2 Department of Pathology, University of California, 3 Division of Surgical Oncology and Department of Surgery, Moores UCSD Cancer Center, University of California, San Diego, La Jolla, CA, USA.
authors.forename: Jason K
authors.initials: JK
authors.lastname: Sicklick
keywords: Biliary tract cancer; gallbladder carcinoma; metastasis; nodule
references.citation: Eur J Surg Oncol. 2013 Jun;39(6):548-53
references.pmid: 23522952
references.citation: Postgrad Med. 1986 Dec;80(8):111-6
references.pmid: 3786272
references.citation: Gastroenterology. 2004 May;126(5):1448-53
references.pmid: 15131804
references.citation: Lancet Oncol. 2003 Mar;4(3):167-76
references.pmid: 12623362
references.citation: Gynecol Oncol. 2003 Sep;90(3):682-5
references.pmid: 13678747
references.citation: Ann Surg. 1962 Jul;156:114-24
references.pmid: 13891308
references.citation: Surg Oncol Clin N Am. 2001 Apr;10(2):243-55, vii
references.pmid: 11382585
references.citation: Curr Treat Options Oncol. 2013 Sep;14(3):337-49
references.pmid: 23686724
references.citation: Clin Nucl Med. 2010 Apr;35(4):267-8
references.pmid: 20305419
references.citation: Trop Gastroenterol. 2012 Apr-Jun;33(2):155-8
references.pmid: 23025069
references.citation: Eur J Surg Oncol. 2008 Mar;34(3):306-12
references.pmid: 17964753
references.citation: Hepatobiliary Pancreat Dis Int. 2010 Oct;9(5):553-4
references.pmid: 20943468
references.citation: Hepatobiliary Pancreat Dis Int. 2009 Apr;8(2):209-11
references.pmid: 19357037
references.citation: Lancet. 1971 Jun 5;1(7710):1151-3
references.pmid: 4102860
references.citation: Surg Laparosc Endosc. 1995 Feb;5(1):59-63
references.pmid: 7735543
references.citation: CA Cancer J Clin. 2001 Nov-Dec;51(6):349-64
references.pmid: 11760569
references.citation: Radiol Oncol. 2011 Dec;45(4):292-5
references.pmid: 22933968
references.citation: J Gastroenterol. 2014 May;49(5):923-31
references.pmid: 23807230
references.citation: J Hepatobiliary Pancreat Surg. 2009;16(4):557-61
references.pmid: 19373429
references.citation: Hepatology. 1999 Mar;29(3):879-82
references.pmid: 10051492
references.citation: Nat Rev Cancer. 2004 Sep;4(9):695-706
references.pmid: 15343276
references.citation: Int J Cancer. 2006 Apr 1;118(7):1591-602
references.pmid: 16397865
references.citation: Rare Tumors. 2013 Mar 08;5(1):e7
references.pmid: 23772306
references.citation: Clin Exp Metastasis. 1992 May;10(3):191-9
references.pmid: 1582089
references.citation: J Med Case Rep. 2012 Jul 19;6:212
references.pmid: 22812693
references.citation: Arch Surg. 1971 Dec;103(6):767-9
references.pmid: 5120206
references.citation: Urology. 1982 Apr;19(4):373-6
references.pmid: 7072028
references.citation: J Natl Cancer Inst. 1997 Aug 6;89(15):1132-8
references.pmid: 9262251
references.citation: Contemp Oncol (Pozn). 2012;16(5):451-2
references.pmid: 23788928
references.citation: Pathol Oncol Res. 2002;8(3):204-19
references.pmid: 12516003
references.citation: Indian J Nucl Med. 2013 Jul;28(3):190-1
references.pmid: 24250036
references.citation: Int J Cancer. 2013 Oct 1;133(7):1664-71
references.pmid: 23504585
references.citation: Updates Surg. 2011 Sep;63(3):223-6
references.pmid: 21442344
references.citation: Langenbecks Arch Surg. 2002 Oct;387(5-6):222-8
references.pmid: 12410358
references.citation: Clin Nucl Med. 2013 Nov;38(11):e433-4
references.pmid: 24096996
references.citation: Diagn Cytopathol. 2011 Dec;39(12):882-7
references.pmid: 22081524