Collecting duct carcinoma, Bellini tumour

Definition

This tumour is currently poorly defined.

Epidemiology

These are rare tumours.

Macroscopic appearances

These tumours occur in the renal medulla.

Histopathology

The cytological appearances are high grade. There is marked desmoplasia.

Immunohistochemistry

	Pancytokeratin KL-1	3/5 (diffuse positivity of more than 80% of tumour cells; 1, heterologous positivity of less than 50% of tumour cells; 2: study by tissue microarray)2
	34bE12	0/5 (study by tissue microarray)2
	Cam5.2	4/5 (diffuse positivity of more than 80% of tumour cells; 3, strong positivity of 50-80% of tumour cells; 1: study by tissue microarray)2
	CK7	2/5 (strong positivity of 50-80% of tumour cells in 2 cases: study by tissue microarray)2
	EMA	3/5 (diffuse positivity of more than 80% of tumour cells; 2, heterologous positivity of less than 50% of tumour cells; 1: study by tissue microarray)2
	MOC31	1/5 (diffuse positivity of more than 80% of tumour cells in one case: study by tissue microarray)2
	BerEP4	1/5 (strong positivity of 50-80% of tumour cells in one case: study by tissue microarray)2
	RCC Ma	2/5 (strong positivity of 50-80% of tumour cells; 1, heterologous positivity of less than 50% of tumour cells; 1: study by tissue microarray)2
	CD10	2/5 (diffuse positivity of more than 80% of tumour cells; 1, heterologous positivity of less than 50% of tumour cells; 1: study by tissue microarray)2
	E-cadherin	4/5 (diffuse positivity of more than 80% of tumour cells; 2, strong positivity of 50-80% of tumour cells; 1, heterologous positivity of less than 50% of tumour cells; 1: study by tissue microarray)2
	CD15	0/5(study by tissue microarray)2
	Vimentin	2/5 (diffuse positivity of more than 80% of tumour cells; 1, strong positivity of 50-80% of tumour cells; 1: study by tissue microarray)2

Differential diagnosis

• Renal medullary carcinoma, which is restricted to patients with sickle cell anaemia.

• Papillary renal cell carcinoma. The cytogenetic characteristics may be crucial.

• Metastasis, suggested by the cytological appearances of scant cytoplasm and hyperchromatic nuclei.

Prognosis

References

¹Renshaw, A. A. (2002). "Subclassification of renal cell neoplasms: an update for the practising pathologist." Histopathology 41(4): 283-300.

²Pan, C. C., P. C. Chen, et al. (2004). "The diagnostic utility of MOC31, BerEP4, RCC marker and CD10 in the classification of renal cell carcinoma and renal oncocytoma: an immunohistochemical analysis of 328 cases." Histopathology 45(5): 452-9.

This page last revised 10.1.2005.

©SMUHT/PW Bishop