Case Study

CT – Soft tissue neoplasia within the left sartorial muscle, likely mast cell

Firm mass noted on medial, proximal left thigh 3 weeks ago during grooming. No change or growth but was persistent over the past 3 weeks. Aspirate performed- consistent with mast cell tumor.

Physical Exam: All WNL aside from 2-3 cm diameter irregular subcutaneous mass on medial aspect of upper L thigh (inguinal area). Somewhat mobile on palpation. Skin layer above mass appears unaffected.

Firm mass noted on medial, proximal left thigh 3 weeks ago during grooming. No change or growth but was persistent over the past 3 weeks. Aspirate performed- consistent with mast cell tumor.

Image Interpretation

CT of the thighs and abdomen, plain and post contrast – The computed tomography reveals a soft tissue attenuating ovoid mass lesion
embedded within the muscle belly of the left sartorius muscle approximately 5 cm
distal to the left inguinal & femoral ring.
The size of the lesion is 1.5 x 0.5 x 0.5 cm.
The femoral artery and vein are immediately adjacent deep to the mass lesion and
sartorius muscle. The subcutaneous tissue reveals mild reactive fat stranding and
thickening.
There are no large, tumor feeding vessels seen.
Post contrast strong uniform enhancement is noted throughout the mass.
The tributary left inguinal and medial iliac lymph center do not present abnormalities.
There is no sign of metastatic spread to the abdominal organs.

DX

Soft tissue neoplasia with the left sartorial muscle, likely mast cell tumor

Outcome

There are no signs of macroscopic metastatic spread noted.
Critical structures in proximity of the mass within surgical safety margins are the
femoral artery and vein.