A medium buttock mass biopsy (measuring 1 to 3 cm) is a diagnostic procedure performed to investigate a palpable or visualized growth in the gluteal region. Because a mass of this size can range from benign lipomas or cysts to more serious conditions, obtaining an accurate histological diagnosis is essential. During the procedure, a local anesthetic is administered to numb the area. Using imaging guidance (like ultrasound) for precision, a physician then uses a core needle or fine-needle aspiration to extract multiple small tissue samples from the 1–3 cm lesion. The collected tissue is sent to a pathology lab for analysis to determine malignancy and guide appropriate treatment.