The endless differential diagnosis of acute obstructive renal failure: unusual challenges for the sharp-sighted clinician.

Obstruction of urine outflow can result from mechanical blockade as well as from functional defects. In adults, urinary tract obstruction is due mainly to acquired defects, such as pelvic tumors, calculi, and urethral stricture. In childhood it is mostly due to congenital malformations.

[Cancer of unknown primary site origin--advances in diagnosis and therapy].

Cancer of unknown primary site (CUP) is defined as a metastatic disease, identified on biopsy, with it's origin remaining unknown despite extensive clinical, laboratory and imaging studies. As much as 3% to 10% of all cancers can be defined as CUP. The primary workup includes history taking, a full physical examination, basic laboratory studies, imaging studies and immunohistochemical staining or genetic analysis of biopsy material.