Images of the Issue
CT of a renal mucinous tubular and spindle cell carcinoma
Abstract: Mucinous tubular and spindle cell carcinoma (MTSCC) is a rare renal epithelial neoplasm which has only been recently described. It is characterized pathologically by tightly packed, elongated tubules with transition into spindle cell areas and mucinous stroma. Previous literature has laid particular emphasis on its pathology manifestations, while radiological features have not been well studied. We herein report the CT features of a case of MTSCC. The CT findings of MTSCC present certain characteristics in the case. The radiological morphology of this low-grade tumor helps its differentiation from sarcomatoid renal carcinoma.
Key words: Mucinous tubular and spindle cell carcinoma (MTSCC); computed tomography (CT); low-grade
Submitted Oct 22, 2012. Accepted for publication Nov 29, 2012.
CT examination incidentally detected a tumor in the lower
pole of left kidney in an asymptomatic 62-year-old male.
Plain and contrast-enhanced CT scans were performed.
Plain CT showed a high density lesion (21-56 HU, 7.6 cm ×
6.0 cm) relative to renal parenchyma, presenting as a wellmarginated
solid mass without a lobulated appearance and
without fat (Figure 1A). Nodular and line shape calcification
was observed in the mass (Figure 1B). Contrast-enhanced
CT showed slight inhomogeneous enhancement of the
mass (Figure 1C). Evaluation of the pattern of dynamic
enhancement revealed the pattern of “lightly slow wash-in”
(Figure 1C,DD). CT findings were suspicious for a solid renal
Figure 1 A. Plain CT image shows a large tumor in the lower pole
of left kidney with heterogeneous density, measuring 7.6 cm × 6.0 cm
in size; B. Plain CT images shows line shape calcification at the
margin of the mass (arrow) and nodular shape calcification in the
mass (arrow head); C. Contrast-enhanced CT images of arterial
phase (left) and venous phase (right) show slight enhancement of
the mass and slightly patchy low attenuation in some areas of the
mass (arrow); D. Contrast-enhanced CT images show the tumor
part located in the kidney was less enhanced compared with normal
The patient underwent nephrectomy. The nephrectomy
specimen measured 18 cm × 13 cm × 5 cm. Grossly, the
nephrectomy specimen revealed a well-circumscribed
7 cm × 7 cm × 5 cm renal mass, located in the lower pole
of left kidney. The gross cut surface showed a fleshy
texture with regions of grey-white, grey-yellow and greyred
appearance (Figure 2A). The tumor was composed of
tightly packed small bland tubules, spindle cells and partial
mucinous stroma (Figure 2B). Immunohistochemistry was
performed using standard methods. The tumor cells were
positive for cytokeratins AE1/AE3, P504S, CD57, VIM,
NSE, and negative for cytokeratins 34BE12/HCK, Act,
CD10, CD117, CK34, CK7, Inhibin-a, VEGF. Ki-67 <10%.
Figure 2 A. Nephrectomy specimen displays a large welldemarcated
tumor in the lower pole of the left kidney. The tumor
is grey-yellow and grey-red in color, and bulges the contour of
the involved kidney; B. Histological appearance of primary renal
MTSCC, showing bland small tubules, spindle cells, and mucinous
MTSCC is a new entity in pathological classification
proposed by the WHO in recent years. With increased
understanding and recognition of the tumor, it should be
considered as a primary differential diagnostic possibility
from sarcomatoid renal carcinoma.
Disclosure: The authors declare no conflict of interest.
Cite this article as: Yang Y, Zhang J, Huan Y, Xu J. CT of
a renal mucinous tubular and spindle cell carcinoma. Quant
Imaging Med Surg 2012;2(4):292-293. DOI: 10.3978/