IgG4-related paratesticular pseudotumor in a patient with autoimmune pancreatitis and retroperitoneal fibrosis: an extrapancreatic manifestation of IgG4-related disease

Hum Pathol. 2012 Nov;43(11):2084-7. doi: 10.1016/j.humpath.2012.05.017. Epub 2012 Sep 10.


In this report, we describe the first case of a patient with an IgG4-related paratesticular pseudotumor. He had histologically proven autoimmune pancreatitis, then later developed a scrotal mass. The orchiectomy specimen revealed that this was a paratesticular pseudotumor with histopathologic and immunohistochemistry findings characteristic of IgG4-related disease. Paratesticular pseudotumors are uncommon causes of intrascrotal masses and have an unexplained pathogenesis. A variety of genitourinary manifestations of IgG4-related disease including IgG4-related tubulointerstitial nephritis, IgG4-related ureteral pseudotumors, and IgG4-related prostatitis has been previously reported. The current case highlights the need to have a high index of suspicion for IgG4-tissue infiltration in patients with known autoimmune pancreatitis, particularly those with a pseudotumor.

Publication types

  • Case Reports

MeSH terms

  • Aged
  • Autoimmune Diseases / complications
  • Autoimmune Diseases / drug therapy
  • Autoimmune Diseases / immunology
  • Autoimmune Diseases / pathology*
  • Glucocorticoids / therapeutic use
  • Granuloma, Plasma Cell / complications
  • Granuloma, Plasma Cell / immunology
  • Granuloma, Plasma Cell / pathology*
  • Humans
  • Immunoglobulin G / blood*
  • Male
  • Orchiectomy
  • Pancreatitis / complications
  • Pancreatitis / drug therapy
  • Pancreatitis / immunology
  • Pancreatitis / pathology*
  • Prednisone / therapeutic use
  • Retroperitoneal Fibrosis / complications
  • Retroperitoneal Fibrosis / immunology
  • Retroperitoneal Fibrosis / pathology*
  • Testicular Diseases / complications
  • Testicular Diseases / immunology
  • Testicular Diseases / pathology*
  • Treatment Outcome


  • Glucocorticoids
  • Immunoglobulin G
  • Prednisone