Medical Image of the Week: Fast-growing Primary Malignant Mediastinal Mixed Germ Cell Tumor

Figure 1. A: Chest radiograph taken 3 months prior to presentation. B: Chest radiograph showing large mediastinal mass (arrows). C: Coronal view of thoracic CT in soft tissue windows showing the large mediastinal mass (arrows). D: Lateral view of thoracic CT showing large mediastinal mass.

A 28-year-old man presented with progressive hemoptysis for two weeks. He had fever, cough, and night sweats for one month prior to admission that was treated as inflenza, bronchitis and/or pneumonia. He had started to experience anorexia, dysphagia, fatigue, a 30-pound weight loss, panic attacks, and the new onset of hypertension during the 3 months prior to admission. He also had intermittent middle chest pain that was aggravated by coughing for 5 months, but a cardiac catherization two months prior failed to show an abnormality. The chest x-ray and CT scan on this admission demonstrated a 15 cm large anterior mediastinal mass exerting a mass effect on the heart and medistial lymphadenopathy (Figure 1-B,C,D) which were absent on a chest x-ray performed 3 months prior to admission (Figure 1A). Core biopsy and immunohistochemical staining revealed a mixed germ cell tumor with components of seminoma and yolk-sac tumor. He was started on chemotherapy, to which he responded well. The malignant mediastinal germ cell tumor in this case is fast-growing and most likely of extragonadal origin. The majority of tumors occ in men between 20 and 35 years (1). The symptoms of these tumor and nonspecific as described in our case, which may lead to a low index of suspicion of malignant tumor with resultant delayed diagnosis.

Yufei Tian, Stella Pak, and Qiang Nai

Department of Medicine

University of Toledo Medical Center

Toledo, Ohio USA

Reference

1. Carter BW, Marom EM, Detterbeck FC. Approaching the patient with an anterior mediastinal mass: a guide for clinicians. J Thorac Oncol. 2014 Sep;9(9 Suppl 2):S102-9. [CrossRef] [PubMed]

Cite as: Tian Y, Pak S, Nai Q. Medical image of the week: fast-growing primary malignant mediastinal mixed germ cell tumor. Southwest J Pulm Crit Care. 2017;15(3):114-5. doi: https://doi.org/10.13175/swjpcc103-17 PDF

Medical Image of the Week: Tumor-Induced Hypoglycemia

 

Figure 1. CT of the abdomen with IV contrast (axial image) demonstrating numerous large enhancing liver metastases (red oval) and tumor thrombus in the anterior segment branch of the right portal vein (arrow).

A 39 year-old man with a history of widely metastatic (brain, liver and lung) nonseminomatous germ cell tumor was admitted to the hospital with severe abdominal pain and altered mental status. A CT of the abdomen and pelvis with IV contrast revealed a marked increase in the size of the liver metastases, portal vein tumor thrombus and changes of pseudocirrhosis. There were numerous large heterogeneously enhancing masses within the liver parenchyma with central necrosis (Figure 1).

The patient had significant and sustained hypoglycemia, with the lowest glucose recorded of 30 mg/dl. He required multiple IV doses of 50% dextrose and an infusion of 10% dextrose to maintain a serum glucose level greater than 55 mg/dl. His mental status improved with treatment of the hypoglycemia. The patient decided to pursue a palliative approach to care and was discharged with home hospice services.

Tumor-induced hypoglycemia (TIH) is a paraneoplastic syndrome that is uncommon in clinical practice (1). The more common cause of TIH is insulin hypersecretion in the setting of pancreatic beta-cell tumors. Mechanisms that may lead to TIH without insulin hypersecretion include the hypersecretion by tumors of insulin-like growth factor 2 (IGF2) and it’s precursors, insulin-like growth factor 1 (IGF1), somatostatin, and glucagon-like peptide 1. Other pathogenic causes of hypoglycemia include tumor autoimmune hypoglycemia, massive tumor burden, massive tumor liver infiltration, and pituitary or adrenal gland destruction by the tumor. TIH unrelated to pancreatic tumors is called non-islet-cell tumor hypoglycemia (NICTH). The most common cause of NICTH is the hypersecretion of IGF2 and IGF2 precursors by the tumor. This results in increased glucose consumption peripherally and decreased production of glucose in the liver. We did not measure levels of IGF2 in our patient. It was felt the most likely cause of his hypoglycemia was extensive tumor invasion and destruction of the liver due to his advanced disease.

Pavan Parashar MD¹, Meghan Bullock BSN, RN, OCN, Linda Snyder MD²

¹Department of Medicine, Geriatrics, Palliative and General Medicine, Banner University Medical Center-Tucson

²Department of Medicine, Pulmonary, Critical Care and Palliative Medicine, Banner University Medical Center-Tucson

Reference

1. Iglesias P, Díez JJ. Management of endocrine disease: a clinical update on tumor-induced hypoglycemia. Eur J Endocrinol. 2014;170(4):R147-57. [CrossRef] [PubMed] 

Reference as: Parashar P, Bullock M, Snyder L. Medical image of the week: tumor-induced hypoglycemia. Southwest J Pulm Crit Care. 2015;10(5):300-1. doi: http://dx.doi.org/10.13175/swjpcc049-15 PDF