U.S. patent application number 11/363227 was filed with the patent office on 2006-08-17 for radio guided seed localization of imaged lesions.
Invention is credited to Charles E. Cox, Emilia L. Dauway.
Application Number | 20060184018 11/363227 |
Document ID | / |
Family ID | 26800152 |
Filed Date | 2006-08-17 |
United States Patent
Application |
20060184018 |
Kind Code |
A1 |
Cox; Charles E. ; et
al. |
August 17, 2006 |
Radio guided seed localization of imaged lesions
Abstract
A method of removing lesions by implanting a radioactive seed at
the location of the lesion, locating the lesion with the
radioactive seed, and removing the lesion with the radioactive
seed.
Inventors: |
Cox; Charles E.; (Tampa,
FL) ; Dauway; Emilia L.; (Newcastle, WA) |
Correspondence
Address: |
SALIWANCHIK LLOYD & SALIWANCHIK;A PROFESSIONAL ASSOCIATION
PO BOX 142950
GAINESVILLE
FL
32614-2950
US
|
Family ID: |
26800152 |
Appl. No.: |
11/363227 |
Filed: |
February 27, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10292377 |
Nov 12, 2002 |
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11363227 |
Feb 27, 2006 |
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09413293 |
Oct 6, 1999 |
6496717 |
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10292377 |
Nov 12, 2002 |
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60103169 |
Oct 6, 1998 |
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Current U.S.
Class: |
600/436 |
Current CPC
Class: |
A61B 6/4258 20130101;
A61B 2090/392 20160201; A61N 5/1027 20130101; A61B 6/502 20130101;
A61B 2090/3908 20160201 |
Class at
Publication: |
600/436 |
International
Class: |
A61B 6/00 20060101
A61B006/00 |
Claims
1. A method of removing lesions by: implanting a radioactive seed
at the location of a lesion; locating the lesion by detecting the
radioactivity of the implanted radioactive seed with a device
external to a patient's body in which the radioactive seed has been
implanted; and removing the lesion with the radioactive seed.
2. The method according to claim 1, wherein said implanting step
further includes the steps of placing the radioactive seed at the
location of the lesion using radioactive imaging and verifying
proper placement of the radioactive seed.
3. The method according to claim 2, wherein said placing step
further includes locating the lesion using a radioactive image and
injecting the radioactive seed at the location found by the
radioactive image.
4. The method according to claim 2, wherein said verifying step
further includes confirming with an additional radioactive image
that the radioactive seed is located at the location of the
lesion.
5. The method according to claim 1, wherein said locating step
further includes the step of running a radiation detector across
the skin surface to determine the highest radiation count.
6. The method according to claim 1, wherein said removing step
further includes anesthetizing the area containing the radioactive
seed and lesion, surgically removing the lesion, the radioactive
seed and a small amount of surrounding tissue; and then verifying
that the radioactive seed has been removed.
7. The method according to claim 6, wherein said verifying step
further includes placing the radiation detector on the lesion,
radioactive seed and the surrounding tissue to take an ex vivo
radiation count.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser.
No. 10/292,377, filed Nov. 12, 2002; which is continuation of U.S.
application Ser. No. 09/413,293, filed Oct. 6, 1999, now U.S. Pat.
No. 6,496,717; which claims priority to U.S. Provisional
Application Ser. No. 60/103,169, filed Oct. 6, 1998, all of which
are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field
[0003] The present invention relates to methods of localizing
lesions. More specifically, the present invention relates to
methods of localizing lesions using radioactive seeds.
BACKGROUND ART
[0004] Localization of non-palpable lesions for biopsy or excision
during surgery is a necessary procedure. Several techniques are
currently available. As described herein, these techniques have
several disadvantages and improved methods are needed.
[0005] Mammography is credited with the detection of clinically
occult cancer of the breast at greater than 80% sensitivity. Since
breast biopsies increase the overall cost of screening for breast
cancer and 70% of the detected lesions are benign, there is
controversy regarding the cost effectiveness of such biopsies.
Therefore, the development of more effective biopsy techniques are
a significant goal.
[0006] There are three different ways to biopsy occult breast
lesions. These include "core-needle" biopsy, "ABBI" (Advanced
Breast Biopsy Instrumentation), and open surgical excision biopsy.
Open surgical excision biopsy, using needle localization, has been
the standard for diagnosis of non-palpable lesions in the breast
for the past 20 years.
[0007] Although needle localized breast biopsy (NLBB) has some
advantages, it has several disadvantages. It requires highest-level
skill in placement by radiologists. The method requires flexible
wires which are difficult for surgeons to palpate. Currently used
wires may be dislodged during transfer of the patient, or displaced
from the site of the radiographically located suspicious lesion.
When cut inadvertently with scissors, the wires may leave metal
fragments in the patient's breast, which has resulted in
litigation. A potential for thermal injury to the breast exists
when electrocautery is used near the wire. If the insertion site of
the wire is too far from the lesion, there is a dilemma in planning
the incision to include both the wire and the lesion. This
situation can lead to removing more breast tissue than necessary.
There are increased costs related to additional x-rays which are
used to confirm that the lesion has been excised, longer operating
room time fees, specimens require transfer to radiology by
operating room personnel, taking a film of the specimen by a
radiology technician and finally interpretation and notification by
a radiologist.
[0008] Recently, several patents have issued pertaining to devices
and methods for the removal of lesions from soft tissue. However,
these patients do little to overcome the problems detailed above.
Specifically, U.S. Pat. No. 5,807,276 to Russin, issued September
1998, discloses a device and method for using a K-wire which is
positioned through the lesion to be removed. This device requires
that selectable wires be used which can be difficult to maneuver
and may cause infection if not properly sterilized.
[0009] U.S. Pat. No. 5,833,627 to Shmulewitz et al., issued
November 1998, also discloses a needle or cannula of a biopsy
device for insertion into the tissue. This is accomplished by
correlating, in real-time, the actual needle or cannula position
with its probable trajectory once inserted. There is a large amount
of speculation involved in the insertion of the needle into the
breast or other soft tissue, thus increasing the possibility of
removing more soft tissue than is necessary.
[0010] Finally, U.S. Pat. No. 5,855,554 to Schneider et al., issued
January 1999, discloses support plates which contain the breast.
The plates include grids with reference markers for localization
and windows for allowing the physician access to the breast. A
thick biopsy plate containing a plurality of holes fits into the
grid opening through which the biopsy needle is inserted. Again,
the same problems pertaining to the insertion of wires or needles
can occur which can lead to the removal of excess breast
tissue.
[0011] Although the above discussed biopsies are done for the
diagnosis of cancer, it is imperative that physicians treat the
lesions as if they are malignant until it is histologically proven
otherwise. Lesions should be removed by the most direct approach,
as opposed to tracking the lesion and needle through breast tissue.
The surgeon also needs to be aware of the placement of the incision
so that if a mastectomy is necessary in the future, the biopsy scar
can be cleanly excised.
[0012] It is therefore desirable to develop a method whereby
mammographically detected lesions can be localized and excised in a
safe, expeditious, and cost effective manner with the application
of current technologies.
SUMMARY OF THE INVENTION
[0013] According to the present invention, there is provided a
method of removing lesions by-implanting a radioactive seed at the
location of the lesion, locating the lesion for surgery by
detecting the radioactivity of the implanted radioactive seed, and
removing the lesion with the radioactive seed.
DETAILED DESCRIPTION OF THE INVENTION
[0014] The present invention provides a method of removing lesions
from soft tissues or bone by implanting a radioactive seed at the
location of the lesion, locating the lesion by detecting
radioactivity from the radioactive seed and then removing the
lesion along with the radioactive seed.
[0015] The present method utilizes radiographic imaging or x-ray
techniques such as CT scan, PET scan, MRI, or mammography to ensure
that the radioactive seed is implanted in the exact location of the
lesion, thus eliminating unnecessary removal of soft tissue, such
as breast tissue, during the biopsy.
[0016] As further defined and explained below, the term "implanted"
means placing by needle placement, needle localization, surgery,
injection or otherwise, the radioactive seed proximate to or within
the lesion. This provides a precise target for the surgeon based
upon a reliable identification of the lesion by radiographic
imaging. By radioactive seed, it is meant that a radioactive, inert
pellet is utilized. Such pellets can be made from an implantable
metal, such as titanium, and the pellet also contains a
radioisotope. The radioimmission can be gamma radiation or other
emissions which are benign to the lesion and tissue and can just be
detected by known detecting devices and methods. An example of such
a radioactive seed is disclosed in U.S. Pat. No. 5,460,592 to
Langton et al., assigned to Amersham.
[0017] In the past, radioactive seeds have been used for temporary
as well as permanent implantation. The recaptured seeds can be
sterilized for reuse. The most popular use for therapeutic seeds
have been in the treatment of meningiomas and prostate cancer. At
the Moffitt Cancer Center, improved seed placement technique has
been developed for prostate brachytherapy, which has significantly
contributed to the decreased morbidity and increased efficacy of
the procedure.
[0018] The use of low dose seeds, which are temporarily placed, are
useful for diagnostic purposes by guiding the biopsy of the
suspicious lesion with the assistance of a hand-held gamma
detecting probe (Navigator, USSC, Neoprobe, Dublin) or other
radiation detecting device, such as a beta radiation detecting
device. The present invention utilizes a single 125-I seed of the
lowest possible activity (<0.30 mci). This amount of
radioactivity is significantly less than a standard mammogram or
chest x-ray, however can be detected by the hand-held gamma probe
to guide the surgeon in the biopsy process.
[0019] These probes have been especially designed to assist in
detecting radioactive materials used for diagnostic purposes during
surgery. Examples of these procedures include radioimmunoguided
surgery (RIGS) for the detection of colorectal tumors and sentinel
lymph node mapping for melanoma and breast cancer. Sentinel lymph
node mapping, a procedure well known to the Moffit Cancer Center,
involves injecting filtered technetium-99 labeled sulfur colloid
(450 uci/5cc) at the primary tumor site and allowing time for this
substance to infuse the lymphatic channels. The seed guided breast
biopsy utilize radioactive material which would be contained in
titanium and have no direct contact with the tissue.
[0020] More specifically, the present invention provides a method
of localization using the radioactive seeds and hand-held gamma
detectors for surgery. The radioactive seed is localized to a
lesion by use of imaging technology. The surgeon can then determine
the location of the seed during surgery using a hand-held gamma
detector. This allows localization without guide wires, a potential
source of infection. Further it reduces the number and location of
incisions that must be made and which must be considered in future
surgeries.
[0021] The radioactive seed can be placed and localized to at least
the bone, brain, lung, GI tract, intestines, stomach, liver,
kidneys, GU tract including prostate, soft tissues, fatty lesions
or muscle, pancreas, adrenal or any other site that can be
radiographically images or otherwise localized.
[0022] Localization can be done with standard radiographs such as
mammograms, ultrasound, MRI, CT scan or any other scanning
technology that can localize an otherwise non-visible or
non-palpable lesion.
[0023] In one example of the method, radioactive-guided breast
biopsy is utilized. It is a safe, expeditious and cost-effective
technique to biopsy non-palpable breast lesions. Low dose
radioactive seeds are disposed proximate to a lesion under
radiographic guidelines. The seeds are localize the non-palpable
breast lesion which allows them to be more effectively excised with
reduced operative time.
[0024] In a further example of the use of the present invention,
interstitial brachytherapy is used. Interstitial brachytherapy has
had many applications in the treatment of various malignant
neoplasms. The development of accurate placement of radioactive
seeds has eliminated many of the problems related to interstitial
brachytherapy from past years. A variety of seeds have been
developed to take advantage of their individual characteristics.
The most widely used radioactive seed for prostate brachytherapy
incorporates I-125, however any seed can be used which is
detectable by a radiation sensing device. The iodine source is
encapsulated in a titanium shell. The titanium combines low
radiation absorption with good strength and tissue tolerance. I-125
has a half-life of 60 days and a gamma radiation of only 27 kev.
The seeds are available at a length of 4.5 mm and diameter of 0.8
mm, which passes easily through a standard 18-gauge needle.
[0025] The above discussion provides a factual basis for the use of
radio guided seed localization of imaged lesions. The utility of
the present invention is shown by the following non-limiting
examples.
EXAMPLE 1
[0026] Mammographic placement of a single 125-I seed by the
radiologist is performed. Once the patient is placed in the
mammographic device and the location of the lesion is determined,
the skin is cleansed. Local anesthetic is injected at the site of
the placement. An 18-gauge needle with sterile bone wax occluding
the tip is loaded with a single 125-I seed. The needle is placed
into the breast tissue under mammographic guidance to the
suspicious lesion. A stilette is placed into the bore of the needle
displacing the seed through the tip. The needle and stilette
apparatus are removed from the breast tissue. The seed location is
confirmed to be at the lesion with mammography and films are taken.
The patient is then taken to the operating room.
[0027] The patient is prepared and draped in the normal sterile
fashion. A sterile sleeve is placed over a Neoprobe.TM. gamma
counter. The hand-held probe is then run across the skin surface of
the breast, marking the exact point of highest count. This clearly
identifies the location of the seed and lesion. This area is then
anesthetized with local anesthetic. A number 15 blade scalpel is
used to make the skin incision. The lesion is removed with the seed
in place together with a small margin of surrounding breast tissue.
The probe is placed on the specimen and an ex vivo count is taken
of the specimen, confirming that the seed has been removed. The
specimen is taken to the specimen processing room. The lesion in
the specimen is localized using the gamma detection probe. The
specimen is linked using a red color at the hot spot and black for
the remaining margins. The specimen is sectioned across the red
spot and the seed is removed, placed in a lead container and sent
to Radiation Oncology Department for storage. Cytology is made from
the lesion for diagnosis. The specimen is fixed in formalin and
processed in a routine manner.
[0028] By utilizing the present invention, the radiologist need not
consider the angle of the placement of the wire and therefore the
surgeon has the choice of making the incision directly over the
lesion. Therefore, there is less tunneling through the breast and
less breast tissue need be removed during the biopsy. Additionally,
there is a higher likelihood of immediate localization of the
lesion by the surgeon since the use of mammography on site is being
provided. There is also a lower possibility of missing a lesion
since a hand-held probe can be used to confirm removal of the
lesion and the radioactive seed.
[0029] Further, the seeds are reusable. This eliminates expense and
time required for x-ray imaging of the specimen. Less operating
room time is required based on not having to waiting for x-ray
confirmation of removal of the lesion. Finally, there is no chance
of wire dislodgment, cutting of wire, or retained fragments of wire
in the breast tissue which therefore lowers the infection rate
since wires are not at all utilized in the present invention.
EXAMPLE 2
[0030] Needle localized breast biopsy (NLBBx) has been the standard
for diagnosis of nonpalpable lesions for the past 20 years. Low
dose radioactive seed localization (RSL) can be used in conjunction
with a hand held gamma detector (HHGD) to localize nonpalpable
breast lesions and accurately remove the radiographic lesion with
reduced operative time (OT) and-tissue volume (TV).
Methods
[0031] A titanium seed containing 0.05-0.1 mCi of I125 is placed
with mammographic or ultrasound guidance localizing the suspicious
breast lesion. The HHGD is used to externally locate the seed. The
incision is placed directly over the seed/lesion. The HHGD directs
the excision and verifies seed/lesion removal. A specimen
radiograph (S-Xray) was performed to confirm the seed/lesion
removal. Variables included OT, TV, surgeon retrieval success
(SRS), and pathologist retrieval success (PRS). Success of
identification of the seed/lesion by the surgeon and pathologist
were assessed prior to S-Xray utilizing the HHGD.
Results
[0032] Fifteen patients underwent successful RSL of nonpalpable
breast lesions. OT, TV of RSL and TV of 15 randomly reviewed
NLBBx's, SRS and PRS were calculated. The RSL-TV was statistically
smaller than the NLBBx-TV (P<0.001). TABLE-US-00001 1 RSL-OT
RSL-TV NLBBx-TV SRS PRS (Avg. min) (Avg. cm3) (Avg. cm3) (%) (%)
4.60 + 0.49 19.3 + 3.9 40.3 + 12.2 100 100
Conclusions
[0033] RSL is a safe, time efficient, tissue-sparing method of
breast biopsy for image detected lesions. It provides rapid
reliable localization by radiologist, surgeon and pathologist
possibly eliminating S-Xrays, same day localization, poor wire
placement and infection potential of external wires.
EXAMPLE 3
Materials and Methods
[0034] Patients were recruited from the Comprehensive Breast Center
who had been referred for suspicious mammographically detected
lesions requiring NLBB. Variables analyzed included the size and
weight of the specimen, total time in the operating room, surgeon
retrieval success, and cumulative radiation exposure to the
surgeon, radiologist and pathologist.
[0035] The technique involves placing a titanium seed containing
0.05-0.1 mCi of I-125 into an 18-gauge needle with sterile bone wax
occluding the tip. The apparatus is placed into the breast
parenchyma under radiographic guidance (mammography or ultrasound).
A stilette is placed into the needle displacing the seed through
the tip localizing the lesion. The seed localization is confirmed
to be at the lesion with mammography.
[0036] After surgical preparation, the sterile sheathed HHGD is
utilized to identify location of the seed/lesion by counts of
radioactivity. After administration of a local anesthetic, the
specimen is removed using the HHGD to guide the depth of
dissection. The HHGD is placed on the specimen and an ex-vivo count
is taken of the specimen confirming that the seed has been removed.
(Initially for the purpose of this study, an x-ray of the specimen
was taken to prove that the ex-vivo count was an acceptable
replacement for the specimen x-ray.) The pathologist also uses the
HHGD to identify and remove the seed from the specimen. The
specimen is processed in a routine manner.
Results
[0037] Fifteen patients underwent successful removal of RSL of
nonpalpable breast lesions. The operative time from incision to
specimen removal was 4.60+0.49 min which ranged from 1 to 8
minutes. Tissue volume of the RSL biopsy specimens were compared to
15 randomly selected NLBB specimens. The RSL specimens average
tissue volume was 19.3 cm3+3.9 compared to 40.3cm3+12.2 for NLBB
specimens (p<0.001).
[0038] The surgeon was able to retrieve the seed and the lesion and
the pathologist able to find the seed in the specimen 100% of the
time. The specimen x-ray confirmed retrieval of the lesion in all
cases. Definitive on table verification of seed removal by the HHGD
occurred likewise 100% of the time. The radiation exposure to the
patient, radiologist, surgeon, pathologist and ancillary staff is
documented to be minimal by the use of radiation badges and rings
worn throughout the procedure.
Conclusion
[0039] In summary, the goal was to devise a method whereby
mammographically detected lesions can be localized and excised in a
safe, expeditious and cost effective manner with application of
current technologies. RSL biopsy is a technically feasible
procedure requiring minimal radiation exposure and can be performed
in an outpatient setting using local anesthetics. RSL and the use
of HHGD allow for accurate placement of the incision and precise
depth of dissection resulting in less tissue loss. Finally, with
enhanced mammographic placement, reduction in operative time and
potential replacement of the specimen mammogram, should result in
significant cost reduction. The use of low dose diagnostic seeds
can be applied to lesions in other organs such as bone, brain,
liver, lung, colon, adrenal, kidney, and prostate.
[0040] Throughout this application, various publications and
patents, are referenced with patents by number and other
publications by author and year. Full citations for the
publications are listed below. The disclosures of these
publications and patents in their entireties are hereby
incorporated by reference into this application in order to more
fully describe the state of the art to which this invention
pertains.
[0041] The invention has been described in an illustrative manner,
and it is to be understood that the terminology which has been used
is intended to be in the nature of words of description rather than
of limitation.
[0042] Obviously, many modifications and variations of the present
invention are possible in light of the above teachings. It is,
therefore, to be understood that within the scope of the appended
claims, the invention may be practiced otherwise than as
specifically described.
* * * * *