The document discusses principles of biopsies. It begins by stating that the purpose of a biopsy is to confirm a suspected diagnosis, and that it is not a substitute for other diagnostic tests and evaluations. It provides indications for biopsies, such as aggressive bone or soft tissue lesions, large or deep soft tissue lesions, or unclear diagnoses in symptomatic patients. It notes when biopsies are not necessarily indicated, such as for asymptomatic or likely benign lesions. It then describes different types of biopsies and provides guidance on open incisional biopsies, including using a longitudinal incision and not exposing neurovascular structures.

1. Biopsy Principles
DR. GACHANA M
PGY I
SEPTEMBER,2022

2. Introduction
Purpose of the biopsy is to confirm a suspected diagnosis
The biopsy is not a substitute for a thorough history,
physical exam, and laboratory investigation
• prerequisites for a biopsy
• CBC, platelets, coagulation studies
• cross-sectional imaging to evaluate local anatomy
• treatment center performing biopsy must be capable of proper
diagnosis and treatment
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3. Indications for biopsy
• aggressive bone or soft tissue lesions
• soft tissue lesions larger than 5cm, deep to
fascia, or overlying bone/neurovascular
structures
• unclear diagnosis in a symptomatic patient
• solitary bone lesions in a patient with history
of carcinoma
Indications
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4. When a biopsy is not indicated
 asymptomatic latent bone lesions or a symptomatic active
bone lesions which appear entirely benign on imaging don't
necessarily need a biopsy
 soft tissue lesion which are completely benign on MRI don't
necessarily need a biopsy (e.g. lipoma, hemangioma)
 Types of biopsy
 Fine Needle Aspiration (FNA)
 provides cytologic (cellular) specimen
 frequently used for carcinoma
 not typically used for sarcoma
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5. Types of biopsy
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Core biopsy (Tru-cut)
• allow for tumor structural
examination
• can evaluate both the
cytologic and stromal
elements of the tumor
• frequently used for soft
tissue sarcoma
• 85-95% accuracy in
diagnosis
Incisional biopsy
• small surgical incision
carefully placed to access
tumor without
contamination of critical
structures
Excisional biopsy
• select indications: small,
superficial soft tissue
masses

6. • Principles of the open incisional biopsy 6
• use longitudinal incision in the extremities
• allows for extension of the incision for definitive management
Incision
• do not expose neurovascular structures
• all tissue exposed during the biopsy is considered contaminated with tumor
• maintain meticulous hemostasis
• post-operative hematomas are considered contaminated with tumor
• release tourniquet prior to wound closure
Approach

7. Biopsy
• perform through the involved compartment of the tumor
• for bone lesions with a soft tissue mass, it is ok to perform
the biopsy using the soft tissue mass
Closure
• if using a drain, bring drain out of the skin in line with
surgical incision
• allows drain site to be removed with definitive surgical
extensile incision
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8. THANK YOU
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