- Discussion:
- may be accomplished with a large needle or by open surgical methods;
-
needle bx:
- involves less disturbance to tissue & is usually less extensive;
- where the soft tissue or bone lesion is accessible and near surface, needle biopsy is often a simple matter;
- when inserting the biopsy needle, it is essential that the pathologist be aware of respecting tissue planes,
- it is esp helpful technique when the diagnosis can be made on basis of a small number of cells, such as in
metastatic cancer;
- two types of biopsies include: fine needle and core needle biopsies;
-
fine needle biopsy:
- relies on cytologal interpretation by an experienced pathologist;
- its accuracy (65 to 95%) is determined in part by the adequacy of the collected tissue sample;
- it does not allow for immunohistochemical analysis;
-
core needle biopsy:
- uses trocar cannula system, with a outer sleeve which closes over the trocar, capturing the sample of tissue;
- provides more tissue than fine needle and allows for immuno-histochemical analysis;
- accuracy ranges between 75 to 95%;
-
disadvantages of needle bx:
- are that tissue obtained may be from necrotic portion of tumor and therefore not suitable for dx, or tissue may be reactive
in nature and not representative of actual tumor;
- M.C. Skrzynski et al. (JBJS 1996) recommend caution when a myxomatous tumor is diagnosed by needle biopsy, and recommend
and recommend an incisional biopsy for confirmation;
- references:
-
Clinical Utility of Percutaneous Biopsies of Musculoskeletal Tumors.
-
Needle biopsy of musculoskeletal lesions. A review of 208 procedures.
-
Aspiration biopsy of primary neoplasms of bone.
-
Diagnosis of eosinophilic granuloma of bone by cytology, histology, and electron microscopy of transcutaneous bone-aspiration biopsy.
-
incisional open bx:
- where several areas of a tumor must be evaluated (as seen in cartilagenous lesions), larger sample obtained by open biopsy is to be preferred;
- incisional biopsies are performed (as opposed to excisional biopsies) inorder to minimize contamination of peripheral tissues and to preserve
the tumor's pseudocapsule (which facilitates future tumor excision);
-
need for embolization:
- some lesions such as suspected
renal or thyroid carcinoma should have preoperative embolization, but consideration should be given to embolization
if a non compressible lesion is present (such as might occur with a pelvic or acetabular lesions);
-
pitfalls:
- as a basic principal, the surgeon must be careful not contaminate tissue planes or compartments outside of the tumor's location;
- the classic example is the mistake of placing a drain several cm away from the incision site (which may place tumor cells along the path of the drain;
- likewise transverse incisions will spread tumor cells across compartments;
- incision should go through a single muscle belly when possible (and avoid intermuscular planes);
- percutaneous biopsy should avoid crossing compartments, such as biopsy of a distal femoral lesion through the suprapatellar pouch,
or transversing through an intermuscular septum;
- it is essential that hemostasis be obtained prior to wound closure;
- drains should be placed at either the proximal or distal end of a longitudinally placed incision;
- compression dressing is applied postoperatively
- reference:
-
Possible Metastasis of Osteosarcoma to a Remote Biopsy Site: A Case Report.
- Residual disease following unplanned excision of soft-tissue sarcoma of an extremity. J Bone Joint Surg Am 1996;78:650-655.
- Considerations for Bone Biopsy:
- always contour smooth edges;
- make a circular or a longitudinal oval hole (torsional strength not affected by length of defect);
- attempt to keep defects less than 10% of bone diameter (maintains over 80% of bone strength);
- when biopsy size is greater than 20% of bone diameter, torsional strength decreases to 50%;
The spread of tumor-cell-sized particles after bone biopsy.
The effect of biopsy-hole shape and size on bone strength.
The effect of biopsy-hole shape and size on bone strength.
The hazards of the biopsy, revisited. Members of the Musculoskeletal Tumor Society. Mankin HJ et al. J Bone Joint Surg Am 78:639-643, 1996
THE CLASSIC: The Hazards of Biopsy in Patients with Malignant Primary Bone and Soft-Tissue Tumors.
