Multiple tumors (no viscera involvement)
Multiple tumors (no viscera involvement) typically occur as dozens to hundreds of mostly small tumors located in various areas such as the skin, muscles, and frontal eye socket, These tumors do not involve visceral organs, often take a benign course, and may regress spontaneously. Multiple tumors (with viscera involvement)
Multiple tumors (with viscera involvement) typically occur as dozens to hundreds of tumors located in the same sites as multiple tumors (no viscera involvement) but also occur in one or more visceral organs such as those in the gastrointestinal tract and upper respiratory tract and/or the heart, liver, cerebellum, rectum, parietal cortex of brain, and lung. This form of IMF, particularly in cases with tumors involving the gastrointestinal tract, heart, and/or lung, has a far higher morbidity and mortality than the other forms with death occurring in infants during the first weeks to 4 months of life in 30–70% of cases Death is typically due to a tumors compression of vital organs or tissues (e.g. blood vessels). However, there are uncommon cases of multiple tumors (with viscera involvement) that were not associated with serious symptoms, were observed without treatment, and over time showed spontaneous regressions of all or almost all of their tumors. Pathology
Microscopic histopathologic analyses of IMF tumor tissues commonly show repeated patterns of a central zone consisting of spindle-shaped cells lining capillaries and round-to-oval cells arranged around prominent "antler-shaped" vascular spaces all of which are surrounded by a peripheral zone of clustered smooth muscle-like cells.
Diagnosis
Techniques for the diagnosis of Page kidney are all imaging based, including abdominal x-ray, intravenous pyelography, angiography, renal doppler ultrasound, CT scan, and Magnetic resonance imaging (MRI). X-ray and pyelography may add in diagnosis, but are non-diagnostic when used alone. Additionally, pyelograms use potentially nephrotoxic contrast agents, further limiting their utility. Diagnosis is primarily made using ultrasound and CT. CT and MRI imaging can show the space occupying lesions but doppler ultrasound is needed to display the hemodynamic changes occurring in the kidney. Ultrasound is often the initial diagnostic test of choice but due to its low resolution further imaging may be necessary. Treatment
Surgical
Surgical treatment of Page kidney has evolved over time as newer techniques have become more popular. Open surgical procedures such as nephrectomy, which was once the treatment of choice have been replaced by less invasive options such as percutaneous drainage or endoscopic capsulotomy. Medical
Some cases of Page kidney will resolve spontaneously without need for surgical treatment. In this case, medical treatment focuses on symptomatic treatment of the hypertension with an angiotensin-converting enzyme inhibitor (ACEi) or an angiotensin receptor blocker (ARB). Adding a calcium channel blocker (CCB) or beta blocker to the ACEi or ARB has also been described. History
Irvine H. Page first demonstrated the Page kidney phenomena experimentally in animals in 1939. He found that wrapping one of the animals kidneys in cellophane produced hypertension that could be reversed after removal of the kidney.