Primary squamous cell carcinoma contributes around 0.5 to 15% of all urothelial malignancy. The predisposing factor and causative agents include renal calculi, infection and endogenous and exogenous chemicals, hormonal imbalance and vitamin A deficiency. A 56-year-old female presented with right flank pain on and off with fever for the last one-week duration, imaging study revealed dilated calyx containing pus material, one focus showing a small whitish nodule. On gross examination, there was a complete loss of architecture, and one portion of calyx showed a friable whitish area and one small nodule measuring 1 x 0.5 cm. Microscopically showing an irregular nest with sheets of malignant squamous cells, differentiating into keratin pearls and background is traversed stromal invasion.

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Corresponding author
Pragyamita Datta, Department of Pathology, Jawaharlal Nehru Medical College (DMIHER), Sawangi, Wardha, Maharashtra, India (pragyamita10@gmail.com)