Primary mucinous cystic neoplasms are rare tumours of the kidney, with a very few case reports in the literature. They arise from metaplasia of renal pelvic urothelium. We describe here a 45-year-old male who presented with pain in the abdomen and a lump in the left iliac fossa for two months. Ultrasound and CT scan showed a large, complex, heterogenous mass in the central abdomen and left iliac fossa, suggesting the possibility of dermoid cyst. Excision of the mass showed an enlarged multicystic kidney fi lled with mucin, destruction of renal parenchyma and a small viable area of grey white tumour. Histopathology revealed a peripherally located mucinous cystadenocarcinoma arising in the background of chronic pyelonephritis and mucinous metaplasia. We report this case for the rarity of the lesion and the associated clinical and radiological diagnostic dilemma.

Thyroid tumours with both papillary and medullary carcinoma features are rare and represent less than 1% of all thyroid malignancies. These tumours have a different clinical presentation and biological behaviour from tumours that have only papillary or medullary carcinoma features. The phenomenon of mixed thyroid tumours can be observed in two settings--a mixed tumour showing dual differentiation, or a collision tumour. For a precise diagnosis of this rare mixed thyroid carcinoma, fine needle aspiration cytology results should be correlated with serum calcitonin and thyroglobulin levels. The diagnosis should also be confirmed using immunocytochemistry. Surgery is the treatment of choice, and the role of postoperative radioiodine is controversial. We herein report the case of a 35-year-old man with a mixed medullary-papillary carcinoma of the thyroid, which presented with C-cell hyperplasia, granulomatous inflammation and metastasis to the cervical lymph nodes. The patient was treated with total thyroidectomy and nodal clearance. This case highlights the need for awareness of coexistent entities as they warrant separate treatments.
Adult ; Carcinoma, Medullary ; pathology ; surgery ; Carcinoma, Papillary ; pathology ; surgery ; Humans ; Inflammation ; pathology ; Lymphatic Metastasis ; Male ; Neoplasms, Multiple Primary ; pathology ; surgery ; Photomicrography ; Thyroid Neoplasms ; pathology ; surgery ; Thyroidectomy