Transcript GUIDED PERCUTANEOUS BIOPSY OF RETROPERITONEAL …

INTV11
GUIDED PERCUTANEOUS BIOPSY
OF RETROPERITONEAL LESIONS
Medical Imaging Departement; La Rabta Hospital

INTRODUCTION
 Percutaneous fine-needle aspiration biopsy (PFNAB) under
computed tomographic (CT) guidance has proved to be a widely
accepted method of documenting malignancy.

Refinements in technique, experience with the procedure, and
improvements in CT scanners have permitted a high degree of
accuracy.

We present our experience over a 8-year period with this
technique.
OBJECTIVES
 The aim of this work is to present an overview of Indication of
percutanous needle biopsy which include
 diagnosis of primary or metastatic malignacy in a newly
discovered mass,
 diagnosis of tumor recurrence in patients known with malignancy
 diagnosis of infection and benign disease.
PATIENTS AND METHODS
 we retrospectivly reviewed percutaneous
retroperitoneal biopsies performed in 49 patients
between 2008 and 2011.
 All biopsies were performed by the radiology staff
in the imaging department La Rabta.
 Biopsies were performed under CT guidance: helical
CT (Tomoscan CX / S).
PATIENTS AND METHODS
 The decision of the percutaneous biopsy was multidisciplinary,
taking into account :

the report risk / benefit
 technical feasibility of the procedure.
 Patients were informed of the nature of the act and its possible
risks and especially the importance of their cooperation.
 procedures were done under local anesthesia
 Hemostasis tests were performed before the procedure.
RESULTS
biopsy concerned renal masses in 12 cases revealing:
Histological type
Patients
Carcinoma
5
liposarcoma
1
lymphoma.
3
xanthogranulomatous
pyelonephritis
1
RESULTS

In 8 of the 49 patients with retropenitoneal abnormalities, metastatic
neoplasm was diagnosed, the primitive tumour was :
organ
cases
pancreas
3
kidney
2
lung
1
Urinary tract
1
Undetermined
1
RESULTS
 Biopsy of a retro-peritoneal mass in 32 patients was
nature
cases
Lymphoma
17
metastasis
8
Retroperitoneal
fibrosis
4
•In two of five adrenal biopsy pulmonary metastasis was
shown.
:
RESULTS
•
In 9 cases tissue obtained was inadequate for diagnosis:
•
insufficient sample in 4.
•
hemorrhagic or necrotic in 2.
•
normal parenchyma in 3.
•
In two of five adrenal biopsy pulmonary metastasis was shown.
By side biopsy of an unresectable
medial renal mass.
Biopsy of a left lower pole renal mass
avoiding the necrotic component.
Biopsy of the hypodense right renal
mass. Confirmation of the diagnosis of
lymphoma.
Trans-hepatic adrenal mass biopsy
confirming its metastatic origin
in a patient with a primitive lung.
Discussion
 In our institution, most abdominal aspiration procedures during
the past 9 years were performed under CT control.

CT permits accurate placement of a needle tip into small lesions,
and its proximity to major vessels is readily ascertained.
 The cross-sectional format of CT permits choice of the most
appropriate needle approach to a suspected abnormality (i.e. ,
anterior, posterior, lateral, or oblique)
 The skin puncture site, needle path, and depth can be readily
determined from hard copy images and the measured depth for
sampling directly transposed to the needle with a sterile rule.
DISCUSSION
 Problems related to patient size, bowel gas, dressings and patient
positioning, can all be accommodated by the CT guidance
procedure.
 As the contraindications to CT-guided biopsy
 the lack of patient cooperation,
 coagulation problems
 technical impossibility due to interruption by major vessels and bowel
are noted.
DISCUSSION
 CT-guided biopsy was not indicated in a case that the envisaged path
direction was not considered to be safe due to interruption
 by major vessels,
 bowel and
 vertebral bodies
 enough specimens from the small lesions located at a deep site
should be obtained with satisfactory sample for histological
examination
DISCUSSION
 There is a wide variety of needles from which to choose, with
various needle gauges, tip configurations, and sampling
mechanisms.
 For this discussion, they will be divided into three general
groups:
 small-gauge aspiration needles such as the Chiba: cytology study
 small-guage cutting-core-biopsy needles : difficult path or high
hemorrhagic risk
 larger cutting needles such as the 18-gauge Menghini, 18-gauge
Biopty, and 14-gauge TruCut.
DISCUSSION

Factors to consider when choosing a needle include
 location of the lesion,
 proximity to other structures,
 amount of tissue needed (pathologist’s needs),
 operator preference.
 Aspiration needles are designed to obtain cytologic samples
only. Occasionally, they obtain small pieces of tissue, which can
be processed for histologic examination.
Guillotine needle type tru-cut; chisel tip mandrel bent and made
Guillotine needle with deployed stylet. (b): the tissue core in biopsy needle.
After skin marking the puncture site, disinfection and local anesthesia, the first needle
carrier is introduced to the periphery of the mass.
(b) Performing the biopsy needle through the mandrel.
Discussion
 Before performing any biopsy, the previous
diagnostic studies should be reviewed, and the
clinical findings and information sought should be
discussed with the referring physician in order to
plan the most appropriate procedure.
 Review of the previous diagnostic studies is helpful
in selecting the imaging technique, approach, and
positioning of the patient for the biopsy.
Discussion
 With CT guidance, most lesions are best approached by
choosing a needle path that minimizes the skin-to-lesion
distance.

When this involves traversing bowel or other organs,
and when an alternative route is available, the
alternative route is often chosen to avoid these other
structures.
 However, with thin-needle aspirations in the
immunocompetent patient, it is possible to cross bowel,
stomach, liver, or other structures without unacceptable
risks
Schematic representation of different possible approaches and organs that can be
climbed during percutaneous gestures.
Discussion
 For ease of performance, it is best if the needle
path lies in the axial plane.

This allows the entire needle to be visualized on a
single image.

However, other structures often surround the
lesion and preclude such an approach.

Several authors have described methods used to
approach lesions that were not accessible via a
direct approach.
DISCUSSION
 otherwise inaccessible lesions cqn be approached
 either from above or below and using a geometric approach to
calculate the needle angle (the so-called “triangulation
method”), many ons can be sampled safely.

This is especially valuable in

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renal,
superior retroperitoneal
adrenal lesions
 when avoiding the caudal extent of the pleura is important to
diminish the risk of
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

pneumothorax,
pleural contamination,
malignant seeding of the pleural space.
DISCUSSION
RENAL BIOPSY:
 We can divide the indications for biopsy of renal
masses in two groups:
 Established indications for which there is a sufficient
experience
 Emerging indications that the biopsy remains a topic
of discussion and controversy
DISCUSSION
Established indications :
1.
Atypical renal cell carcinoma: it may be cystic lesion, with fatty component or a low vascular
mass.
2.
An unresectable mass which malignancy is not established.
3.
Suspicion of lymphoma.
4.
The patient with high surgical risk.
5.
A mass, in which the infectious origin is suspected.
Emerging indication:
1.
Homogeneous, not cystic renal mass seen on ultrasound.
2.
A complex cystic mass
3.
Treatment by radiofrequency or cryo-ablation is discussed
DISCUSSION
ADRENAL BIOPSY
 This biopsy is associated with a high rate of complication and the
negative predictive value (80%).
 On the other hand negative biopsy does not allow to formally eliminate
the possibility of a metastasis, or to differentiate between adenoma and
adenocarcinoma.
 The current indications for adrenal biopsy are:
1.
The indeterminate lesions discovered incidentally.
2.
A mass with a relative percentage of wash out upper or equal to 50%.
3.
A benign-looking lesion but increased in size.
DISCUSSION
LYMH NODE BIOPSY
1. Suspicion of lymphoma.
2. Lymphoma and residual masses after treatment.
3. The metastasis, Infectious or during a
granulomatous lymph node.
DISCUSSION
BIOPSY OF RETROPERITONEAL LESIONS:
 Depending on the size of the lesion and its location within the
retroperitoneum,
 either an anterior or posterior approach can be used,
 although the posterior approach is usually preferred and is most
often necessary to ensure a clear path for the use of cutting
needles.
CONCLUSION
 Guided percutaneous biopsy of abdominal lesions
especially
retroperitoneal
lesions
clearly
has
become an important diagnostic tool.
 The success of this technique lies in the accuracy
that can be achieved as well as in its relative safety
and ease of performance.