Magnetic resonance imaging-guided percutaneous biopsy of musculoskeletal lesions

A novel pneumatic drill for bone biopsy under MRI imaging

PURPOSE

Bone biopsies are currently conducted under computed tomography (CT) guidance using a battery-powered drill to obtain tissue samples for diagnosis of suspicious bone lesions. However, this procedure is suboptimal as images produced under CT lack soft tissue discrimination and involve ionizing radiation. Therefore, our team developed an MRI-safe pneumatic drill to translate this clinical workflow into the MR environment, which can improve target visualization and eliminate radiation exposure. We compare drill times and quality of samples between the 2 drills using animal bones.

METHODS

Five porcine spare rib bones were obtained from a butcher shop. Each bone was drilled twice using the Arrow OnControl battery-powered drill and twice using our pneumatically actuated drill. For this study, we used an 11-gauge bone biopsy needle set with an internal core capturing thread. A stopwatch recorded the overall time of drilling for each specimen obtained.

RESULTS

All 20 samples collected contained a high-quality inner core and cortex. The total average time for drilling with the pneumatic drill was 8.5 s (+ / - 2.5 s) and 7.1 s (+ / - 1.4 s) with the standard battery-powered drill.

CONCLUSION

Both drills worked well and were able to obtain comparable specimens. The pneumatic drill took slightly longer, 1.39 s on average, but this extra time would not be significant in clinical practice. We plan to use the pneumatic drill to enable MRI-safe bone biopsy for musculoskeletal lesions. Biopsy under MRI would provide excellent lesion visualization with no ionizing radiation.

Percutaneous biopsy of musculoskeletal tumors and the potential for needle tract seeding: technical considerations, current controversies, and outcomes

Multidisciplinary communication and planning between the musculoskeletal radiologist and orthopedic oncologist are essential for proper biopsy planning when a primary musculoskeletal malignancy is suspected. Image-guided percutaneous biopsy allows for real-time visualization of the biopsy needle and surrounding structures, combining high diagnostic accuracy with safety and cost-effectiveness. However, determining a surgically optimal biopsy trajectory for a mass can be technically challenging due to critical surrounding anatomy or challenging needle approach angles. Inappropriately placed biopsies can have serious repercussions on patient function and oncological survival. The potential for needle tract seeding and local recurrence after biopsy of sarcoma has been central to the debate regarding the need for excision of the biopsy tract. This multidisciplinary review highlights current controversies in the field, including the issue of core needle biopsy tracts and their excision, technical considerations and advances in image-guidance in the setting of challenging biopsies, advances in histopathological diagnostics with implications for targeted therapy in sarcoma, as well as surgical and oncological outcomes after needle tract biopsy.

Diagnosis of vertebral osteomyelitis

Native vertebral osteomyelitis (NVO) is a potentially fatal infection which has seen a gradual increase in its incidence over the past decades. The infection is insidious, presenting with symptoms of back pain. Fever is present in about 60 % of patients. Prompt diagnosis of NVO is important to prevent the development of complications. Numerous laboratory and imaging tools can be deployed to accurately establish the diagnosis. Imaging techniques such as magnetic resonance, nuclear imaging, and computed tomography are essential in diagnosing NVO but can also be useful in image-guided biopsies. Laboratory tools include routine blood tests, inflammatory markers, and routine culture techniques of aspirated specimens. Recent advances in molecular techniques can assist in identifying offending pathogen(s). In this review, we detail the arsenal of techniques that can be utilized to reach a diagnosis of NVO.

Percutaneous Image-guided Needle Biopsy of Musculoskeletal Tumors: Technical Tips

With recent advances in imaging technology, the frequency of detecting musculoskeletal lesions has also increased. Percutaneous image-guided needle biopsy is occasionally required for the diagnosis of such lesions. Moreover, in the era of personalized cancer care, chances in histopathological diagnosis and the importance of histopathological diagnosis by percutaneous needle biopsy are increasing. However, as percutaneous needle biopsy is not a common procedure for musculoskeletal lesions, careful planning and the application of adequate techniques such as hydrodissection and the trans-osseous approach are occasionally required. In this review, we have summarized the indications and techniques for percutaneous image-guided needle biopsy for musculoskeletal lesions, including lymphatic lesions.

Diagnostic yield, accuracy, and complication rate of CT-guided biopsy for spinal lesions: a systematic review and meta-analysis

BACKGROUND

CT-guided biopsy is a commonly used diagnostic procedure for spinal lesions. This meta-analysis aims to investigate its diagnostic performance and complications, as well as factors influencing outcomes.

METHODS

A systematic review of the literature was performed to identify studies reporting outcomes of CT-guided biopsies for spinal lesions. Diagnostic yield (ie, the rate of procedures resulting in a specific pathological diagnosis) and diagnostic accuracy (ie, the rate of procedures resulting in the correct diagnosis) were the primary outcomes of interest. Complications following biopsy procedures were also included.

RESULTS

Thirty-nine studies with 3917 patients undergoing 4181 procedures were included. Diagnostic yield per procedure was 91% (95% CI 88% to 94%) among 3598 procedures. The most common reason for non-diagnostic biopsies was inadequacy of sample. No difference in diagnostic yield between different locations and between lytic, sclerotic, and mixed lesions was found. Diagnostic yield did not differ between procedures using ≤13G and ≥14G needles. Diagnostic accuracy per procedure was 86% (95% CI 82% to 89%) among 3054 procedures. Diagnostic accuracy among 2426 procedures that yielded a diagnosis was 94% (95% CI 92% to 96%). Complication rate was 1% (95% CI 0.4% to 1.9%) among 3357 procedures. Transient pain and minor hematoma were the most common complications encountered.

CONCLUSION

In our meta-analysis of 39 studies reporting diagnostic performance and complications of CT-guided biopsy, we found a diagnostic yield of 91% and diagnostic accuracy of 86% with a complication rate of 1%. Diagnostic yield did not differ between different locations, between lytic, sclerotic and mixed lesions, and between wide- and thin-bore needles.

MRI-guided percutaneous needle biopsy with 1.2T open MRI: study protocol for a prospective feasibility study (SCIRO-1701)

There has been growing interest in magnetic resonance imaging (MRI)-guided interventional procedures such as percutaneous needle biopsy. Although open MRI is preferable for MRI-guided procedures in terms of patient accessibility, its inferior imaging capability due to lower field strength is a substantial limitation. In this situation, the high-field (1.2T) open MRI has recently become available. This novel MRI system is expected to provide excellent image quality as well as good patient accessibility, potentially contributing to safe and accurate device manipulation. This trial is designed to investigate the feasibility of MRI-guided percutaneous needle biopsy with this system. Patients with lesions needing percutaneous needle biopsy for pathological diagnosis are included. The enrollment of ten patients is intended. The primary endpoint of this study is the feasibility of biopsy needle insertion under real-time MR-fluoroscopy guidance based on the presence of the notch of the biopsy needle within the target lesion. The secondary endpoints are adverse events, device failures, and success of specimen acquisition. Once the feasibility of MRI-guided biopsy with 1.2T open MRI is validated by this study, it may potentially encourage widespread use of MRI-guidance for biopsy procedures. Furthermore, it may lead to development of the other MRI-guided interventional procedures using this MRI system.

An improved biopsy technique for rabbits with VX2 bone tumors

The present study aimed to investigate the efficacy of an improved biopsy method for reducing local exudation and metastasis. After resecting the VX2 tumor in cancer-bearing VX2 rabbits, a tumor cell suspension was prepared. Tumor cells were transplanted into the tibias of 20 rabbits in order to establish a bone tumor model. These adult rabbits underwent a puncture procedure after 2 weeks. All the left tibias were punctured using the improved biopsy method (the experimental group), where bolt closures were implanted into puncture holes through the metallic casing following biopsy. All the right tibias were punctured using a traditional biopsy technique (the control group). Color Doppler ultrasonography was used to assess the exudation of each puncture hole after 1 h. After 7 days, a pathological study was performed on the soft tissue near each puncture hole. The success rate of the bone model was 100% for the 20 rabbits. The exudation rate in the experimental group was lower than that in the control group (25 vs. 80%, respectively; χ2=12.13; P<0.05). The tumor-spreading rate in the experimental group was lower than that in the control group (35 vs. 85%, respectively; χ2=10.41; P<0.05). Overall, it was shown that the improved biopsy method can prevent local bleeding and tumor metastasis.

Biopsy of CT-Occult Bone Lesions Using Anatomic Landmarks for CT Guidance

OBJECTIVE

The purpose of this study is to evaluate the histopathologic diagnostic yield, sample size, procedural time, and dose-length product (DLP) for the biopsy of CT-occult lesions found at MRI or PET or both.

MATERIALS AND METHODS

A retrospective review of our radiology information system for biopsies of CT-occult lesions using CT guidance from January 1, 2010, through December 31, 2014, was performed and compared with a selection of CT-guided biopsies of CT-evident bone lesions during the same period. The data were then evaluated for diagnostic yield of histopathologic diagnosis, procedural time, use of sedation medication, DLP, and size of specimens obtained.

RESULTS

A total of 30 CT-occult biopsies met the inclusion criteria. Twenty-seven of those biopsies had results that were concordant with the patient's primary histopathologic diagnosis, imaging findings, and clinical course. In the CT-evident lesion group, concordant histopathologic abnormalities were identified in 27 of 30 patients. There was a statistically significant increase in number of samples obtained for the CT-evident lesions compared with CT-occult lesions. There was no statistically significant difference in total specimen length, DLP, number of CT scans, procedural time, or use of sedation medication between the CT-occult and CT-evident biopsy groups.

CONCLUSION

Biopsy of CT-occult lesions using anatomic landmarks achieves diagnostic yields similar to those for CT-guided biopsy of CT-evident lesions.

Management of Bone Sarcoma

Treatment of bone sarcoma requires careful planning and involvement of an experienced multidisciplinary team. Significant advancements in systemic therapy, radiation, and surgery in recent years have contributed to improved functional and survival outcomes for patients with these difficult tumors, and emerging technologies hold promise for further advancement.

Accuracy and complications of CT-guided core needle biopsy of peripheral nerve sheath tumours

OBJECTIVE

This single-centre study retrospectively reviews the complications in patients that have occurred following peripheral nerve sheath tumour biopsy, and assesses whether there is an association with biopsy technique or underlying lesion characteristics.

MATERIALS AND METHODS

41 consecutive core needle biopsies of proven peripheral nerve sheath tumours over a 2-year period in a tertiary teaching hospital were reviewed. Patient demographics and symptoms, tumour characteristics and radiological appearances were recorded. Biopsy and surgical histology were correlated, and post-biopsy and surgical complications analyzed.

RESULTS

41 biopsies were performed in 38 patients. 68% schwannomas, 24% neurofibromas and 7% malignant peripheral nerve sheath tumours. Biopsy histology correlated with surgery in all cases. 71% of lesions were surgically excised. 60% of patients reported pain related to their lesion. Following the biopsy, 12% reported increased pain, which resolved in all cases. Pain exacerbation was noted in tumours smaller in size, more superficial and in closer proximity of the biopsy needle tip to the traversing nerve. Number of biopsy needle passes was not associated with an increased incidence of procedure-related pain.

CONCLUSION

Core biopsy of a suspected peripheral nerve sheath tumour may be performed safely before excisional surgery to confirm lesion histology and assist prognosis. There is excellent correlation between core biopsy and excised surgical specimen histology. The most common complication of pain exacerbation is seen in a minority and is temporary, and more likely with smaller, more superficial lesions and a closer needle-tip to traversing nerve distance during biopsy.

Magnetic Resonance Imaging-Guided Spine Interventions

MR imaging-guided interventions for treatment of low back pain and for diagnosis and treatment of soft tissue and bony spinal lesions have been shown to be feasible, effective, and safe. Advantages of this technique include the absence of ionizing radiation, the high tissue contrast, and multiplanar imaging options. Recent advancements in MR imaging systems allow improved image qualities and real-time guidance. One exciting application is MR imaging-guided cryotherapy of spinal lesions, including treating such lesions as benign osteoid osteomas and malignant metastatic disease in patients who are not good surgical candidates. This particular technique shows promise for local tumor control and pain relief in appropriate patients.

MR-guided vertebroplasty with augmented reality image overlay navigation

PURPOSE

To evaluate the feasibility of magnetic resonance imaging (MRI)-guided vertebroplasty at 1.5 Tesla using augmented reality image overlay navigation.

MATERIALS AND METHODS

Twenty-five unilateral vertebroplasties [5 of 25 (20%) thoracic, 20 of 25 (80%) lumbar] were prospectively planned in 5 human cadavers. A clinical 1.5-Teslan MRI system was used. An augmented reality image overlay navigation system and 3D Slicer visualization software were used for MRI display, planning, and needle navigation. Intermittent MRI was used to monitor placement of the MRI-compatible vertebroplasty needle. Cement injections (3 ml of polymethylmethacrylate) were performed outside the bore. The cement deposits were assessed on intermediate-weighted MR images. Outcome variables included type of vertebral body access, number of required intermittent MRI control steps, location of final needle tip position, cement deposit location, and vertebroplasty time.

RESULTS

All planned procedures (25 of 25, 100%) were performed. Sixteen of 25 (64%) transpedicular and 9 of 25 (36%) parapedicular access routes were used. Six (range 3-9) MRI control steps were required for needle placement. No inadvertent punctures were visualized. Final needle tip position and cement location were adequate in all cases (25 of 25, 100%) with a target error of the final needle tip position of 6.1 ± 1.9 mm (range 0.3-8.7 mm) and a distance between the planned needle tip position and the center of the cement deposit of 4.3 mm (range 0.8-6.8 mm). Time requirement for one level was 16 (range 11-21) min.

CONCLUSION

MRI-guided vertebroplasty using image overlay navigation is feasible allowing for accurate vertebral body access and cement deposition in cadaveric thoracic and lumbar vertebral bodies.

Classification, imaging, biopsy and staging of osteosarcoma

Osteosarcoma is the most common primary osseous malignancy excluding malignant neoplasms of marrow origin (myeloma, lymphoma and leukemia) and accounts for approximately 20% of bone cancers. It predominantly affects patients younger than 20 years and mainly occurs in the long bones of the extremities, the most common being the metaphyseal area around the knee. These are classified as primary (central or surface) and secondary osteosarcomas arising in preexisting conditions. The conventional plain radiograph is the best for probable diagnosis as it describes features like sun burst appearance, Codman's triangle, new bone formation in soft tissues along with permeative pattern of destruction of the bone and other characteristics for specific subtypes of osteosarcomas. X-ray chest can detect metastasis in the lungs, but computerized tomography (CT) scan of the thorax is more helpful. Magnetic resonance imaging (MRI) of the lesion delineates its extent into the soft tissues, the medullary canal, the joint, skip lesions and the proximity of the tumor to the neurovascular structures. Tc99 bone scan detects the osseous metastases. Positron Emission Tomography (PET) is used for metastatic workup and/or local recurrence after resection. The role of biochemical markers like alkaline phosphatase and lactate dehydrogenase is pertinent for prognosis and treatment response. The biopsy confirms the diagnosis and reveals the grade of the tumor. Enneking system for staging malignant musculoskeletal tumors and American Joint Committee on Cancer (AJCC) staging systems are most commonly used for extremity sarcomas.

Adult soft tissue sarcoma local recurrence after adjuvant treatment without resection of core needle biopsy tract

BACKGROUND

Core needle biopsies of sarcomas allow a diagnosis in a high percentage of patients with few complications. However, it is unclear whether the tract needs to be excised to prevent recurrences.

QUESTIONS/PURPOSES

We therefore determined the rates of recurrence and metastases in patients with Stage III extremity sarcomas, who underwent wide local resection without excision of the needle tract and also received adjuvant treatment.

METHODS

We retrospectively reviewed 59 adult patients with deep, larger than 5 cm, high-grade soft tissue sarcomas of the upper or lower extremity treated between January 1999 and April 2009. All the patients underwent a core needle biopsy. Resection was performed with wide margins. The biopsy tract was not resected during the definitive surgery. Fifty-seven patients (97%) received preoperative and/or postoperative radiation, whereas 49 patients (83%) received chemotherapy. Local recurrence and distant recurrence rates were determined. The minimum followup was 24 months (median, 56 months; range, 24-122 months).

RESULTS

The local recurrence rate was 9%. Fifteen patients (25%) developed metastasis after diagnosis. Seven of the 59 patients (12%) had microscopic positive margins at resection.

CONCLUSIONS

Our data demonstrate no increase in local recurrence rates or rates of metastatic disease compared with previously published studies when resection of the core biopsy tract was not performed.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Tru-cut biopsy as the initial method of tissue diagnosis in bone tumors with soft tissue extension

BACKGROUND

Tru-cut biopsy in suspected bone tumors can be performed even in less specialized centers. Tru-cut biopsy has been proved as safe with more than 90% accuracy. However, its usefulness was not widely studied in general hospitals where Tru-cut biopsy is performed by orthopedic surgeons. This study was conducted to find out the accuracy and adequacy of Tru-cut biopsy performed by an orthopedic surgeon not trained in musculoskeletal oncology, in a general hospital.

MATERIALS AND METHODS

A study was conducted through a prospectively collected database using a uniform protocol. All patients who had a malignant appearing bone lesion with a palpable soft tissue mass were included in the current study. Fifty such consecutive cases underwent Tru-Cut biopsy by orthopedic residents or registrars who were aware of the principles of Tru-cut biopsy and the recommendations of Musculoskeletal Tumor Society. When an open biopsy or a resection of the tumor was subsequently performed, the histological diagnosis was compared for accuracy with the diagnosis of needle biopsy. We evaluated adequacy of sample obtained and accuracy of diagnosis in terms of sensitivity, specificity, positive predictive value, and negative predictive value.

RESULTS

Seventy seven cases were initially enrolled. Out of which 18 were excluded and 59 patients were biopsied. Out of which 50 were analysed. Only 4 out of 50 biopsied specimens were inadequate resulting in an adequacy rate of 92%. Among 46 cases, which were analyzed for diagnostic accuracy, 84.78% had true-positive result, 8.69% had true negative, and 6.52% had false-negative report. The sensitivity and specificity of Tru-cut biopsy in our series was 92.85% and 100%, respectively, with positive predictive value of 100% and negative predictive value of 57.14%.

CONCLUSIONS

Tru-cut biopsy can be recommended as an initial method of tissue diagnosis in musculoskeletal tumors with soft tissue extension.

Initial experience with percutaneous biopsies of bone lesions using XperGuide cone-beam CT (CBCT): technical note

PURPOSE

This paper describes our preliminary experience with percutaneous bone biopsy under XperGuide conebeam computed tomography (CBCT) guidance.

MATERIALS AND METHODS

Seventeen patients (11 men and 6 women; mean age 57.8; range 17-81) with 17 bone lesions underwent biopsy with XperGuide CBCT (Philips Medical System, Best, The Netherlands). The mean diameter of the lesions was 2.32 cm (range 1-8 cm). Technical success (defined as the correct positioning of the needle within the lesion), diagnostic accuracy, sensitivity and specificity were evaluated. Complication rate was also recorded.

RESULTS

The technical success rate was 100%. In 15 patients, a sample of adequate material for histopathological analysis to yield a definitive diagnosis was obtained; in two patients, the sample was inadequate for a definitive diagnosis. In one of these two cases, the lesion was closely followed up for 1 year, during which it remained stable in size, and as a result, it was considered a false positive; the other was considered a false negative. Diagnostic accuracy, sensitivity and specificity were 94.12%, 90.91% and 100%, respectively. No major complications were recorded; only one patient had slight bleeding, with a consequent small haematoma, which reabsorbed in about 15 days.

CONCLUSIONS

Bone biopsy under XperGuide CBCT guidance can be considered accurate as a result of the combination of real-time needle orientation and spatial resolution of CT fluoroscopy. Moreover, our results are encouraging in terms of complication rate, diagnostic accuracy, sensitivity, specificity and reduction of CT workload.

Performing MR-guided biopsies in clinical routine: factors that influence accuracy and procedure time

OBJECTIVE

To assess the accuracy, the duration and factors that influence the duration of MRI-guided liver or soft-tissue biopsies.

METHODS

Nineteen liver biopsies and 19 soft-tissue biopsies performed using 1.5T-MRI guidance were retrospectively analysed. Diagnostic performance and complications were assessed. Intervention time was subdivided into preparation period, puncture period and control period. Correlation between procedure time and target size, skin-to-target-distance, used sequences and interventionalists' experience were analysed.

RESULTS

Overall sensitivity, specificity and accuracy were 0.86, 1.0 and 0.92, respectively. Two minor complications occurred. Overall median procedure time was 103.5 min. Liver biopsies lasted longer than soft-tissue biopsies (mean([soft-tissue]): 73.0 min, mean([liver]): 134.1 min, P < 0.001). The most time consuming part was the preparation period in both, soft-tissue and liver biopsies corresponding to 59.6% and 47.4% of the total intervention time, respectively. Total procedure time in liver biopsies (P = 0.027) and puncture period in liver and soft-tissue biopsies (P ([liver]) = 0.048, P ([soft-tissue]) = 0.005) was significantly prolonged for longer skin-to-target-distances. Lower numbers of image acquisitions (P ([liver]) = 0.0007, P ([soft-tissue]) = 0.0012) and interventionalists' experience reduces the procedure duration significantly (P < 0.05), besides all false-negative results appeared during the first five biopsies of each individual radiologist.

CONCLUSION

The interventionalists' experience, skin-to-target-distances and number of image acquisition influence the procedure time significantly.

KEY POINTS

•Appropriate training and supervision is essential for inexperienced interventionalists. •Two perpendicular image orientations should confirm the correct biopsy needle position. •Communication between interventionalist and technician is essential for a fluent biopsy procedure. •To shorten intervention time appropriate previous imaging is essential.

The impact of imaging speed of MR-guided punctures and interventions in static organs--a phantom study

PURPOSE

Verification of MR-guidance with image acquisitions slower than 1 image per second as it is inevitable for some interventions. Therefore, we quantified solely the effect of acquisition-time on the efficiency of MR-guided interventions in a static phantom study.

MATERIALS AND METHODS

We measured the duration, accuracy and error rate of simulated interventions for different acquisition-times using a simplified interventional setup. All measurements were performed in a 1.0 T open MRI scanner. Imaging was performed with a gradient-echo sequence (flipangle=20°; TR/TE=12/6 ms; voxelsize=1 mm×1 mm; slicethickness=5 mm; FOV=230 mm×200 mm; acquisition-time=1 s). Variable acquisition times were simulated with intermediate pauses of 0, 1, 2, 3, 4 and 5 s. The interventions were performed by a total of 20 volunteers including 7 experienced interventionalists.

RESULTS

The mean duration of the intervention was 2 min. Significant differences between experienced and unexperienced volunteers were limited to the localization of the image plane and corrections made. The mean accuracy was 5.6 mm. The time to localize the image plane increased with deceleration of imaging from 24 s to 49 s. A similar increase was observed for the intervention time (55-108 s). A significant influence of the acquisition-time on durations and corrections was only found with acquisition-times greater than 4s per image.

CONCLUSION

Even image rates of several seconds per image are sufficient enough for efficient interventions in static organs. Thus, the main attention has to be turned on the visibility of the needle when sequences are optimized for MR-guidance. The minimization of imaging speed is rather of secondary interest.

Analysis of nondiagnostic results after image-guided needle biopsies of musculoskeletal lesions

BACKGROUND/RATIONALE

Image-guided needle biopsies are commonly used to diagnose musculoskeletal tumors, but nondiagnostic (ND) results can delay diagnosis and treatment. It is important to understand which factors or diagnoses predispose to a ND result so that appropriate patient education or a possible change in the clinical plan can be made. Currently it is unclear which factors or specific lesions are more likely to lead to a ND result after image-guided needle biopsy.

QUESTIONS/PURPOSES

We therefore identified specific factors and diagnoses most likely to yield ND results. We also asked whether an image-guided needle biopsy of bone and soft tissue lesions is an accurate and clinically useful tool.

METHODS

We retrospectively reviewed data from a prospectively collected database for a case-control study of 508 image-guided needle biopsies of patients with suspected musculoskeletal tumors between 2003 and 2008.

RESULTS

The interpretations of 453 of the 508 (89%) needle biopsies were accurate and clinically useful. Forty-five biopsies (9%) were ND and 10 (2%) were incorrect (IC). Bone lesions had a higher ND rate than soft tissue lesions (13% vs. 4%). The specific diagnosis with the highest ND rate was histiocytosis. Elbow and forearm locations had higher ND rates than average. Malignant tumors had a higher IC rate than benign tumors (5% vs. 0%); fibromyxoid sarcoma and rare subtypes of osteosarcoma had higher IC rates than other diagnoses. Repeat needle or open biopsies were performed in 71 (14%) patients. Bone lesions were more likely than soft tissue lesions to require repeat biopsies (18% vs. 9%).

CONCLUSIONS

A high rate of accuracy and clinical usefulness is possible with image-guided needle biopsies of musculoskeletal lesions. We believe these biopsies appropriate in selected circumstances but a key factor for appropriate use is an experienced musculoskeletal tumor team with frequent communication to correlate clinical, radiographic, and histologic information for each patient.

A comparison of fine-needle aspiration, core biopsy, and surgical biopsy in the diagnosis of extremity soft tissue masses

BACKGROUND

Biopsy tissue can be obtained through a fine needle, a wider coring needle, or through an open surgical incision. Though much literature exists regarding the diagnostic yield of these techniques individually, none compare accuracy of diagnosis in the same mass.

QUESTIONS/PURPOSES

We asked how the diagnostic accuracy of fine-needle aspiration, core biopsy, and open surgical biopsy compare in regard to identifying malignancy, establishing the exact diagnosis, and guiding the appropriate treatment of soft tissue masses.

PATIENTS AND METHODS

We prospectively studied 57 patients with palpable extremity soft tissue masses, performing fine-needle aspiration, followed by core biopsy, followed by surgical biopsy of the same mass.

RESULTS

Open surgical biopsy was 100% accurate on all accounts. With regard to determining malignancy, fine-needle aspiration and core biopsy had 79.17% and 79.2% sensitivity, 72.7% and 81.8% specificity, 67.9% and 76% positive predictive value, 82.8% and 84.4% negative predictive value, and an overall accuracy of 75.4% and 80.7%, respectively. In regard to determining exact diagnosis, fine-needle aspiration had a 33.3% accuracy and core biopsy had a 45.6% accuracy. With regard to eventual treatment, fine-needle aspiration was 38.6% accurate and core biopsy was 49.1% accurate.

CONCLUSIONS

In soft tissue mass diagnosis, core biopsy is more accurate than fine-needle aspiration on all accounts, and open biopsy is more accurate than both in determining malignancy, establishing the exact diagnosis, and the guiding appropriate treatment.

Recurrent osteoid osteoma: interstitial laser ablation under magnetic resonance imaging guidance

Thermal ablation has become a therapy of choice in the treatment of osteoid osteomas. To date, computed tomography has been the standard imaging modality for minimally invasive treatment regimes. We report a case of a 46-year-old man with a recurrent osteoid osteoma in the right tibial head after CT-guided drill excision and repeat treatment with laser ablation under open high-field MRI guidance. We describe the steps of the interventional MRI procedure and discuss related innovative guidance and monitoring features, and potential benefits of MRI compared with CT-guided techniques. In conclusion, MR-guided laser ablation was proved to be safe and effective.

Office-based core needle biopsy of bone and soft tissue malignancies: an accurate alternative to open biopsy with infrequent complications

BACKGROUND

Biopsy is a critical step in the diagnosis of musculoskeletal malignancy. As an alternative to open biopsy, percutaneous core needle biopsy techniques have been developed. As many studies combine office-based, image-guided, and operative biopsies, the accuracy of office-based core needle biopsy is not well documented.

QUESTION/PURPOSES

We asked whether (1) office-based core needle biopsy for the diagnosis of malignant musculoskeletal neoplasms would have few complications and diagnostic and accuracy rates comparable to those cited in the literature for core needle biopsy, (2) diagnostic errors related to office-based core needle biopsy would result in surgical treatment errors, and (3) tissue core quantity and tumor type would affect accuracy.

PATIENTS AND METHODS

We retrospectively reviewed 234 patients with 252 core needle biopsies of malignant bone and soft tissue neoplasms at one institution between 1999 and 2007. Biopsy accuracy and errors were determined on the basis of histologic evaluation of prior or subsequent biopsies and/or resected specimens, when available. We eliminated 19 patients who had needle biopsies: three had the core needle biopsy completed in the operating room and 16 had insufficient documentation or followup, leaving 233 for study.

RESULTS

Of the 233 core needle biopsies, 212 (91%) were diagnostic and accurate for malignancy. Fourteen (6%) biopsies were nondiagnostic. Major errors, defined as a benign diagnosis in a malignant tumor, occurred in seven cases (3%). Minor errors, defined as errors in histopathologic diagnosis or grade, occurred in 24 biopsies (10%). All nondiagnostic and major core needle biopsy errors were identified and addressed with either a diagnostic open biopsy or definitive wide local excision, resulting in no surgical treatment errors. Accuracy was not influenced by core number; however, myxoid lesions showed a correlation with biopsy error. There were no biopsy-related complications.

CONCLUSIONS

Office-based core needle biopsy for diagnosis of malignant musculoskeletal neoplasms has high diagnostic and accuracy rates without associated complications.

LEVEL OF EVIDENCE

Level II, diagnostic study. See the Guidelines for Authors for a complete description of the level of evidence.

Biopsy of soft tissue masses: evidence-based medicine for the musculoskeletal tumor society

The literature contains a number of controversies regarding key questions: (1) When is a biopsy indicated? (2) How should the biopsy be placed? (3) How should the biopsy be performed and which has the greatest diagnostic accuracy? (4) Who should perform the biopsy? (5) What clinical parameters present the greatest diagnostic difficulty? Using PubMed and Google Scholar we performed English-language literature searches of clinical studies reporting biopsy of soft tissue masses. Thirty-two studies met the inclusion criteria but were only able to address three of the five questions the authors had hoped to evaluate. Available evidence suggests open biopsy has the highest diagnostic accuracy over core needle biopsy, which was higher than fine needle aspiration. There was no evidence to address who is best suited to perform the biopsy (general surgeon, orthopaedic surgeon, radiologist, pathologist) in terms of accuracy of diagnosis. Frozen section at the time of biopsy may improve diagnostic accuracy. Diagnostic difficulty was associated with myxoid and round cell neoplasms, infections, and tumors located in the paraspinal region. The limited number of references addressing these issues demonstrated the need for more Level I research in the area of biopsy of soft tissue masses.

LEVEL OF EVIDENCE

Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Imaging-guided percutaneous biopsy of pathologic fractures: a retrospective analysis of 129 cases

OBJECTIVE

The purpose of our study was to determine the diagnostic performance of imaging-guided percutaneous needle core biopsy and the factors associated with a nondiagnostic biopsy in patients with a pathologic fracture of the appendicular skeleton.

MATERIALS AND METHODS

A retrospective audit was performed of 129 consecutive patients presenting with a pathologic fracture. All patients underwent percutaneous needle core biopsy using CT (n = 98), fluoroscopy (n = 15), or ultrasound (n = 16) guidance. In all cases, either MRI or CT was available before biopsy to assess the presence and degree of the extraosseous tumor mass. The resulting sample was classified as diagnostic (group 1) or nondiagnostic (group 2) on histopathologic study. Diagnostic performance was evaluated on the basis of the diagnostic yield and the diagnostic accuracy, and these were related to the site of the lesion and presence or absence of an extraosseous mass.

RESULTS

Ninety-nine masses (77%) were classified as group 1 and 30 (23%) as group 2. The average cross-sectional diameter of lesions in group 1 was 5.7 x 5.9 cm. Of the 30 lesions composing group 2, no soft-tissue component was identified on prebiopsy cross-sectional imaging in 27 lesions (90%), but the remaining three (10%) showed a smaller extraosseous soft-tissue component compared with the lesions in group 1.

CONCLUSION

Imaging-guided core biopsy is a reliable method for obtaining a tissue diagnosis in pathologic fracture of the appendicular skeleton with a high rate of accuracy. However, those lesions that are purely intraosseous or have only very small extraosseous components are more likely to be associated with a nondiagnostic biopsy and should be considered for a primary open procedure.

Diagnosis and staging of spine tumors

Persistent axial pain with or without neurologic changes should prompt workup for a possible tumor of the spine. Metastatic disease is more predominant than primary tumors, but still needs adequate evaluation before any management. The various steps of evaluation, diagnosis, and staging are reviewed.

Surgical management of primary osteosarcoma

Surgical strategies for the primary tumor for patients with extremity and pelvis osteosarcoma have evolved from the ablative to limb-sparing approaches over the past three decades. Favorable oncologic and functional outcomes with contemporary tissue-conserving techniques consistently observed in skeletally mature patients have prompted the application of similar approaches to a growing number of eligible skeletally immature patients. In response to emerging long-term outcome data, current strategies have focused principally on refining the nature and scope of surgical resection to preserve uninvolved tissues, and on the adoption of novel biological and nonbiological skeletal and soft-tissue reconstruction methods to optimize function. We focus on these clinical issues and discuss current efforts to advance the surgical management of the primary tumor and address the limitations of the definitive treatment of the primary tumor, including locally recurrent disease and complications of skeletal reconstructions.

Biopsy of tumors of the musculoskeletal system

INTRODUCTION

Malignant tumors of the musculoskeletal system are rare, and their symptoms are non-specific. The diagnosis of primary malignant tumors of bone or soft tissue by tissue biopsy is necessary before multimodal treatment with chemo- and/or radiotherapy and resection can be provided. These biopsies are straightforward surgical procedures; they must, however, be performed according to the guidelines if high rates of error and complications are to be avoided.

METHODS

Selective literature review.

RESULTS

Biopsies are either incisional or excisional. There are guidelines for the performance of both kinds. The biopsy channel is inevitably contaminated with tumor cells and thus must be completely removed together with the tumor. Excisional biopsies are indicated only for the histopathological diagnosis of small (< 5 cm), epifascial soft-tissue tumors and small, slowly growing bony tumors that are considered most likely to be benign. If in doubt, an incision biopsy should be performed.

DISCUSSION

The complication rate of tumor biopsies is known to be higher when they are performed in an institution without extensive experience in the treatment of sarcoma. Thus, patients with musculoskeletal tumors that are suspected of being malignant should be referred to a suitable tumor center for biopsy.

[Radiological diagnostics of malignant tumors of the musculoskeletal system in childhood and adolescence]

Rhabdomyosarcoma, osteosarcoma and Ewing's sarcoma are the most common malignant tumors of the musculoskeletal system in childhood and adolescence representing about 10% of newly diagnosed cancers in children and adolescents.In the last two decades the prognosis of patients with such malignancies improved significantly. On the one hand because of the advances in chemotherapy and orthopedic surgery, on the other hand also because of the innovations in radiological diagnostics. The precise pre-therapeutical staging of tumors of the musculoskeletal system provides important prognostic information and has impact on the entire therapy management. During respectively after therapy, imaging is extremely important in the follow-up and in diagnosing a possible recurrent disease.Modern imaging diagnostics of musculoskeletal tumors basically consist of conventional X-ray, of computed tomography (CT) and magnetic resonance imaging (MRI), and of modalities of nuclear medicine such as szintigraphy, positron emission tomography (PET) and PET CT.