Peter Weibl, Ivan Lutter, Milan Obšitník, Peter Lengyel, Ferdinand Kiss, Jozef Gembeš, Svetozár Náter, Martin Blažek, Boris Kollárik, Martin Romančík, Ján Breza
Introduction: Small solid lesions of kidneys are diagnostic dilemma as CT or MRI examinations do not reveal any obvious signs of aggression. The aim of this review article is to summarize problems of small renal cell carcinomas with the focus on diagnostics and their prognosis. Material and Methods: Information was acquired via Medline/Medscape computerized retrieval and on the basis of manual literature search of bibliographic data. Results: USG and CT/MRI are the primary diagnostic tools. The importance of biopsy of the solid renal mass focus has been lately apparent for significant increase of benign lesions in patients who underwent radical or partial nephrectomy for highly suspected renal cell carcinoma (RCC). One of the main causes is the fact that pathological enhancement on the CT or MRI is also present in oncocytomas, atypical angiomyolipomas, adenomas and complex cysts. In some patients even small RCC (< 4 cm in diameter) can progres rapidly and they have unfavourable histopathological parameters. Conclusion: The effort to differ and select these carcinomas leads to definition of new prognostic parameters and developement of mathematical integrated systems with the aim to predict the prognosis of patients and biological behavior of renal cell carcinomas. Incorporation of relevant prognostic parameters and molecular markers into integrated systems and new TNM classification can help to better stratify the patients with RCC as it is with the last TNM classification.