A Diagnostic Dilemma: Metastatic Testicular Cancer and Systemic Sarcoidosis – A Review of the Literature

Sarcoidosis is a multisystem disease that most commonly involves the lungs and the lymph nodes, but with genitourinary tract involvement, can easily mimic testicular cancer with metastasis to the lungs. We describe the case of a 30-year-old African-American male who presented with complaints of a headache, skin lesions, and a scrotal mass. A computed tomography scan of the head showed lesions in the frontotemporal and pons region, causing obstructive hydrocephalus. An ultrasound of the scrotum showed an enlarged epididymis bilaterally as well as a solid hypoechoic ill-defined mass on the right side, separate from the intact testis. Given the high suspicion for testicular malignancy with brain metastasis, a right orchiectomy was completed. The pathology revealed non-caseating necrotizing granulomas that stained negative for tubercular and fungal organisms, which was consistent with sarcoidosis. Additionally, the patient's skin and central nervous system (CNS) lesions improved on steroids that had been started for cerebral edema. Given the predilection of testicular cancer for CNS metastasis, neurosarcoidosis can also be mistaken for testicular cancer metastasis to the CNS, as seen in our case. Differentiating testicular cancer from genitourinary sarcoidosis is difficult but can be clarified using a combination of clinical presentation, epidemiology, serum markers (ACE, AFP, B-HCG), biopsies from skin/lymph nodes, and sometimes imaging. It is critical to differentiate genitourinary sarcoidosis from malignancy, as a misdiagnosis can lead to unnecessary surgical interventions, which have important implications for future fertility. There can also be a coexistence of as well as an association between testicular cancer and sarcoidosis, which should be recognized by health care providers

Protein crystal growth in microgravity.

The crystals of most proteins or other biological macromolecules are poorly ordered and diffract to lower resolutions than those observed for most crystals of simple organic and inorganic compounds. Crystallization in the microgravity environment of space may improve crystal quality by eliminating convection effects near growing crystal surfaces. A series of 11 different protein crystal growth experiments was performed on U.S. space shuttle flight STS-26 in September 1988. The microgravity-grown crystals of gamma-interferon D1, porcine elastase, and isocitrate lyase are larger, display more uniform morphologies, and yield diffraction data to significantly higher resolutions than the best crystals of these proteins grown on Earth

Protein crystal-growth results for shuttle flights STS-26 and STS-29

Recent advances in protein crystallography have significantly shortened the time and labor required to determine the three-dimensional structures of macromolecules once good crystals are available. Crystal growth has become a major bottleneck in further development of protein crystallography. Proteins and other biological macromolecules are notoriously difficult to crystallize. Even when usable crystals are obtained, the crystals of essentially all proteins and other biological macromolecules are poorly ordered, and diffract to resolutions considerably lower than that available for most crystals of simple organic and inorganic compounds. One promising area of research which is receiving widespread attention is protein crystal growth in the microgravity environment of space. A series of protein crystal growth experiments were performed on US shuttle flight STS-26 in September 1988 and STS-29 in March 1989. These proteins had been studied extensively in crystal growth experiments on earth prior to the microgravity experiments. For those proteins which produced crystals of adequate size, three-dimensional intensity data sets with electronic area detector systems were collected. Comparisons of the microgravity-grown crystals with the best earth-grown crystals obtained in numerous experiments demonstrate that the microgravity-grown crystals of these proteins are larger, display more uniform morphologies, and yield diffraction data to significantly higher resolutions. Analyses of the three-dimensional data sets by relative-Wilson plots indicate that the space-grown crystals are more highly ordered at the molecular level than their earth-grown counterparts.</p

Protein crystal-growth in microgravity

The crystals of most proteins or other biological macromolecules are poorly ordered and diffract to lower resolutions than those observed for most crystals of simple organic and inorganic compounds. Crystallization in the microgravity environment of space may improve crystal quality by eliminating convection effects near growing crystal surfaces. A series of 11 different protein crystal growth experiments was performed on U.S. space shuttle flight STS-26 in September 1988. The microgravity-grown crystals of gamma-interferon D1, porcine elastase, and isocitrate lyase are larger, display more uniform morphologies, and yield diffraction data to significantly higher resolutions than the best crystals of these proteins grown on Earth