Unusual Imaging Findings Associated with Germ Cell Tumors

Radiographics. 2019 Jul-Aug;39(4):1019-1035. doi: 10.1148/rg.2019180050. Epub 2019 May 24.


Germ cell tumors, because they contain immature and mature elements, can differentiate into different tissue types. They can exhibit unusual imaging features or manifest in a syndromic fashion. The authors describe these features and assign them to one of the following categories: (a) unusual manifestations of metastatic disease (growing teratoma syndrome, choriocarcinoma syndrome, ossified metastases, and gliomatosis peritonei); (b) autoimmune manifestations (sarcoidlike reaction and paraneoplastic syndromes); (c) endocrine syndromes (sex hormone production, struma ovarii, and struma carcinoid); or (d) miscellaneous conditions (ruptured dermoid cyst, squamous cell carcinoma arising from a mature teratoma, Currarino triad, fetus in fetu, pseudo-Meigs syndrome, and pancreatitis). Rare conditions associated with germ cell tumors demonstrate characteristic imaging findings that can help lead to the appropriate diagnosis and management recommendations. When evaluating for potential metastatic disease, alternative benign diagnoses should be considered (eg, growing teratoma syndrome, ossified metastases, ruptured dermoid cyst, gliomatosis peritonei, and sarcoidlike reaction), which may impact management. Germ cell tumors may also lead to life-threatening complications such as extensive hemorrhage from choriocarcinoma metastases or the rupture of mature teratomas, cases in which timely diagnosis is crucial. Autoimmune and endocrine manifestations such as paraneoplastic encephalitis, autoimmune hemolytic anemia, and hyperthyroidism may occur owing to the presence of germ cell tumors and can create a diagnostic dilemma for clinicians. Knowledge of the syndromic and unusual imaging findings associated with germ cell tumors helps guide appropriate management. ©RSNA, 2019.

Publication types

  • Review
  • Video-Audio Media

MeSH terms

  • Anal Canal / abnormalities
  • Anal Canal / diagnostic imaging
  • Autoimmune Diseases / diagnostic imaging
  • Autoimmune Diseases / immunology
  • Carcinoma, Squamous Cell / diagnostic imaging
  • Choriocarcinoma / blood supply
  • Choriocarcinoma / diagnostic imaging
  • Choriocarcinoma / secondary
  • Dermoid Cyst / diagnostic imaging
  • Digestive System Abnormalities / diagnostic imaging
  • Female
  • Fetus / abnormalities
  • Fetus / diagnostic imaging
  • Humans
  • Male
  • Neoplasms, Germ Cell and Embryonal / diagnostic imaging*
  • Neoplasms, Germ Cell and Embryonal / secondary
  • Neoplasms, Neuroepithelial / diagnostic imaging
  • Neoplasms, Neuroepithelial / secondary
  • Neoplasms, Second Primary / diagnostic imaging
  • Ossification, Heterotopic / diagnostic imaging
  • Pancreatitis / diagnostic imaging
  • Pancreatitis / etiology
  • Paraneoplastic Endocrine Syndromes / diagnostic imaging
  • Paraneoplastic Endocrine Syndromes / etiology
  • Paraneoplastic Syndromes / diagnostic imaging
  • Paraneoplastic Syndromes / immunology
  • Peritoneal Neoplasms / diagnostic imaging
  • Peritoneal Neoplasms / secondary
  • Positron Emission Tomography Computed Tomography / methods*
  • Pregnancy
  • Rectum / abnormalities
  • Rectum / diagnostic imaging
  • Sacrum / abnormalities
  • Sacrum / diagnostic imaging
  • Syringomyelia / diagnostic imaging
  • Tomography, X-Ray Computed / methods

Supplementary concepts

  • Currarino triad