Sternalis muscle and right intramuscular lipoma of subscapularis muscle
Diagnosis certain
Presentation
A known case of sigmoid colon cancer under follow-up.
Patient Data
Age: 65 years
Gender: Female
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Sternalis muscles are noted bilaterally ( normal variant) appears as a short flat parasternal muscle, longitudinal in orientation.
Stable incidentally noted right side intramuscular subscapularis muscle lipoma and butterfly vertebra D4 with no suspicious bony lesion.
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Both red arrows pointed to both sternalis muscles.
Case Discussion
This case of cancer sigmoid underwent sigmoidectomy with liver metastasis on chemotherapy under regular follow-up and demonstrates this uncommon anatomic variant to be aware of because it can misdiagnose as a mass.
The sternalis muscle is an uncommon anatomic variant of the chest wall musculature and is of uncertain etiology and function.