Incidentally Detected Squamous Cell Carcinoma of Renal Pelvis in Patients with Staghorn Calculi: Case Series with Review of the Literature
Figure 3
Microphotographs showing (a) well-differentiated SCC with keratin pearl formation seen in Case 1 and (b) poorly differentiated squamous cell carcinoma seen in Case 3. The tumor is comprised predominantly of undifferentiated malignant tumor cells with islands of clearly squamous cells interspersed without keratinisation as seen in this picture; (c) moderately differentiated SCC in Case 4 showing solid sheets of tumor cells arising from the pelvis and infiltrating renal parenchyma. The urothelium lining the pelvis shows squamous metaplasia and dysplasia; (d) the same case showing tumor cells forming true papillae with fibrovascular cores seen in other areas; (e) all cases showed features of chronic pyelonephritis in the surrounding kidney as can be seen here in Case 3; (f) perineural invasion (arrow) of tumor cells seen in Case 2; (g) section from Case 1 with infiltration of the perirenal fat by the tumor cells.
