Mucinous tubular and spindle cell carcinoma of the kidney: a rare case diagnosed in the early postpartum.

A 27-year-old women requesting assistance for an unspecified abdominal pain localized in the right flank that worsened after a recent delivery was discovered to have a solid mass in the upper pole of her right kidney. Radiological findings showed benign characteristics but without a clear diagnosis. Subsequently, a laparotomic nephron-sparing enucleation of a solid, encapsulated, brownish-white mass, localized in the cortical portion of the upper kidney pole, was performed. Pathological examination of the specimen showed a rare mucinous tubular and spindle cell carcinoma with an almost total mucinous component. To our knowledge, this is the first case of this disease discovered during pregnancy or puerperium. A multidisciplinary approach should be mandatory in order to correctly recognize and treat such a rare disease and to avoid administration of excessive adjuvant treatment to patients with a low-grade malignancy during pregnancy or puerperium.