CRITICAL ISSUES OF BIOPSY IN MUSCULOSKELETAL ONCOLOGY: TECHNIQUES, MISTAKES AND HAZARDS

Abstract

Introduction: Based on their experience of over 25 years in musculoskeletal oncology the Authors review indications and problems of the different types of biopsies.

Methods: From the Rizzoli files and the literature most critical procedural problems and mistakes in performing biopsies are examined, with special attention to the consequences of mistakes and impact on treatment. Data of 749 consecutive cases of biopsies over a 12 year period were analysed: cases included were bone lesions with clinical and pathological features of malignancy requiring biopsy. Of these 198 had already had a biopsy elsewhere. Moreover the Rizzoli experience was reviewed in comparison to what reported in major studies in the literature.

Results: Of the 551 cases primarily biopsied at the Rizzoli 28 (5%) required a repeated biopsy. Of 198 cases biopsied elsewhere in 35 cases there was a major diagnostic error and in 18 a minor error (same grade of malignancy but different histotype).

Most common mistakes adversely affecting treatment were wrong skin incisions and/or surgical approach, amount and quality of the biopsy sample, infection.

Discussion: the analysis as well as major series reported in literature confirm that chosing the technique of biopsy and performing is not so simple. Critical task is first of all to properly chose the best technique:fine needle, trocar, incisional, frozen and excisional biopsies have proper indications, as well radioguidance or CT guidance or ultrasound guidance. Main needs are to avoid contamination, to provide an adequate sample of viable tissue and to place the biopsy tract so that it can be removed at definitive surgery. Today CT or MRI guided trocar biopsies are preferable for most bone lesions while ultrasound guided tru-cut biopsies in most soft tissue lesions. Mistakes concern the surgical approach, the site of biopsy, the quality of sample and tissue preservation. Most common mistakes of the unexperienced surgeon are to remove a lesion without a previous histology or to inadequately excise a soft tissue lesion.

Conclusions: Biopsy is the last step of staging before treatment and it is a compromise between the need of having significant tissue and the need to avoid contamination, yet this is by definition an intralesional procedure. Prof. Mario Campanacci used to say that biopsy is an important surgical procedure in the treatment of musculoskeletal tumors and it should be planned and performed by an experienced surgeon or radiologist.