26th June 2023

Solid tumours

The kidney is affected by many different malignant diseases, by direct involvement of the kidneys, or indirectly by involvement of other parts of the urinary tract. The most common cause of this is obstruction from either a primary tumour or metastasis, resulting in a post-renal acute kidney injury. These tumours can include primary renal adenocarcinoma, tumours of the urothelium or bladder, or the cervix. Glomerulonephritis can also occur as a result of an immunological reaction to other tumours or also as a result of a paraneoplastic syndrome.

Hypercalcemia can occur as a paraneoplastic syndrome from a solid tumour. This frequently happens in breast cancer and lung cancer, caused by parathyroid hormone related protein (PTHrP) or secondary to bone metastasis. High levels of calcium can lead to renal complications, such as renal calculi. The acute drop of the glomerular filtration rate that also occurs as a result of hypercalcaemia is thought to be mediated by renal vasculature constriction in response to the high calcium, leading to a reduced glomerular blood flow and filtration. Hypercalcaemia is also associated with increased sodium excretion and water excretion.

Sometimes treatment of leukaemia and lymphoma, or the resultant tumour lysis syndrome with allopurinol, can be complicated by acute interstitial nephritis. Hypercalcemia caused by the release of calcium in tumour lysis syndrome can also occur in this context, as well as in plasma cell tumours such as myeloma.