Renal Mucinous Tubular and Spindle Cell Carcinoma and 18F-Fluorodeoxyglucose-PET/CT Findings

Huge mucinous tubular and spindle cell carcinoma of kidney: A rare case report and literature review

RATIONALE

Mucinous tubular and spindle cell carcinoma (MTSCC) is a variant of renal cell carcinoma newly added to the WHO classification in 2004. It is a rare variant of renal cell carcinoma and sometimes it is not easy to distinguish MTSCC from papillary renal cell carcinoma, chromophobe renal cell cancer, etc. The prognosis of MTSCC is favorable after surgical resection.

PATIENT CONCERNS

A 45-year-old male patient presented with a right renal mass that was detected on ultrasonography incidentally. The computed tomography scan showed a huge homogenous mass with patchy calcification in the central area, and the lesion was slightly enhanced after contrast injection.

DIAGNOSES

According to postoperative pathology, the patient was diagnosed with MTSCC.

INTERVENTIONS

The patient underwent an open transabdominal radical resection of right kidney and right retroperitoneal lymph node dissection.

OUTCOMES

The surgical outcomes were good, and no recurrence or metastasis was observed during the follow-up.

LESSONS

MTSCC is a rare malignancy of the kidney and the prognosis is usually favorable. Preoperative enhanced CT and MRI can help differentiate MTSCC from other renal tumors, so as to provide a more suitable surgical approach for those who need to retain renal function as much as possible.

Renal Mucinous Tubular and Spindle Cell Carcinoma Shows a High Uptake on 18F-FDG PET/CT

We herein report a rare case of mucinous tubular and spindle cell carcinoma (MTSCC) in an 80-year-old woman. A well circumscribed tumor located on the right kidney was discovered incidentally as a result of screening non-contrast CT. Fluorodeoxyglucose positron emission tomography (FDG PET)/CT showed the increased tracer accumulation in the tumor. The histological diagnosis was MTSCC, which is a rare and only recently established subtype of the malignant renal cell carcinoma (RCC). The present case suggests the clinical benefit of a high uptake of FDG combined with enhanced contrast CT in the differentiation of MTSCCs and other RCCs.