Table 3. Severity of hyponatremia and hypercalcemia cases according to tumour stage.

Staging [n]	Serum sodium (mEq/L)					CSC (mmol/L)
	Mild hyponatremia (130 to 135)	Moderate hyponatremia (125 to 129)	Severe hyponatremia (≤124)	Total (% of n)		Moderate hypercalcemia (2.63–2.99)	Severe hypercalcemia (≥3.00)	Total (% of n)
SCLC [102]
Limited stage [28]	6	1	0	7 (25.0)		0	0	0 (0)
Extensive stage [74]	24	4	7	35 (47.3)		4	0	4 (5.4)
TNM staging [522]
Stage I/II [191]	32	5	4	41 (21.5)		6	1	7 (3.7)
Stage IIIA [67]	16	3	0	19 (28.4)		8	1	9 (13.4)
Stage IIIB/IV [264]	73	18	4	95 (36.0)		20	4	24 (9.1)