Bulky malignancies with a high number of dividing cells are particularly seen in haematological cancers, but tumour lysis syndrome can also occur in some solid cancers, for example renal cell carcinoma, small cell lung cancer and breast cancer. Chemotherapy targets all dividing cells, leading to cell death and release of intracellular potassium, phosphate, and nucleic acids. Nucleic acids convert to uric acid. Uric acid and phosphate can precipitate in the renal tubules leading to AKI, which can further worsen hyperkalaemia. This patient has also recently been taking NSAIDs which will contribute to an AKI. Secondary hypocalcaemia can occur due to hyperphosphataemia. A high LDH signifies a high tumour volume.