Spontaneous regression of renal cell carcinoma: Reality or myth?

Table 1 Regression of primary renal cell carcinoma

Case	Year	Type of regression	Histology documented	Follow up (interval)
Hall[53]	1908	Total regression (?)	Entirely necrotic tumor	Not given
Choi et al[33]	1986	Total regression (?)	Cyst-like capsule with necrotic tissue	Not given
			Calcifications and a cluster of tumor cells…
Edwards et al[34]	1996	Partial regression	Residual RCC with marked fibrosis	36 mo
			And calcification
Hamid et al[32]	1998	"Extensive regression"	Extensively hyalinised lesion, also foci	Not given
			Of cells with clear cytoplasm
			Cystic cavity containing necrotic	Not given
			Debris, occasional foci of viable RCC
Lacquaniti et al[35]	1999	Partial regression	Fibrotic involution…..	7 mo
			With few central areas of RCC
Kobayashi et al[8]	2002	Partial regression of primary	No	2 yr
		RCC with inferior V. cava
		Tumor thrombus

RCC: Renal cell carcinoma.