ML20027B962
| ML20027B962 | |
| Person / Time | |
|---|---|
| Issue date: | 08/20/1982 |
| From: | Higginbotham L NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| To: | Nussbaumber D NRC OFFICE OF STATE PROGRAMS (OSP) |
| Shared Package | |
| ML20027A639 | List: |
| References | |
| FOIA-82-335 NUDOCS 8210120030 | |
| Download: ML20027B962 (11) | |
Text
UNITED STATES
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WASHINGTON, D. C. 20555 g
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Donald A. Nussbaumer, Assistant Director for State Agreements MEMORANDUM FOR:
Program, SP Leo B. Higginbotham, Chief, Radiological Safety Branch, IE FROM:
HOSPITAL REPORT ON MISADMINISTRATION OF I-1
SUBJECT:
THERAPY A general comment from our review of the report is that the informationSpecif raises more questions than it answers,in our view at least.
are marked on the enclosed copy.
Questions.regarding these comments should be addressed to Ralph Meyer or Tang Remsen (492-8188).
19 Chief Radiological Safety Branch, IE
Enclosure:
As stated l
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UNITED STATES
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NUCLEAR REGULATORY COMMISSION s.-
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E WASHINGTON, D C. 20S55 i
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FEB 2 31981 Ref: SA/J0L MEMORANDUM FOR: Leo B. Higginbotham, Chief Radiological Safety Branch, IE R. E. Cunningham, Director Division of Fuel Cycle & Material Safety, NMSS FROM:
Donald A. Nussbaumer, Assistant Director for State Agreements Program Office of State Programs
SUBJECT:
HOSPITAL REPORT ON MISADMINISTRATION OF I-125 SEED IMPLANT THERAPY Enclosed is a copy of the report to St. Joseph's Hospital, Albuquerque, New Mexico, on the misadministration of I-125 seed implant therapy.
This was the subject of OSP Notice of Non-Routine Event No. 80-39 (Dec. 2, 1980).
New Mexico has requested NRC assistance in reviewing the report.
In partial response, we have arranged through IE, Region IV to make available to
':aw Mexico the services of William Hendee.
We request your review and comments on the report by c.o.b. February 27, 1981.
Both radiotherapists involved in the incident were certified in Radiology by the American Board of Radiology and it is our understanding that as such, under present NRC licensing practice, would be deemed qualified to use any of the sealed sources for therapy listed in 10 CFR 35.100, Schedule A, Group VI.
The hospital's report however, concluded that a contributing cause was a lack of experience in I-125 implants on the part of the radiotherapists.
The report also attributes the incidents to a lack of conaunication between the developers of the treatment planning computer programs and its users.
Although the report provides no details, we understand that this conclusion was reached after a determination that not all of the instructions for use of the programs had been documented.
If.you have any specific questions please contact Joel Lubenau or me, 27767.
\\
Donald A. Nussbaumer Assistant Director for State Agreements Program Office of State Programs As stated
\\
,f 7 :.. 0ll bl.,osep2 Hospita.
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b u. sters o f C it a r s t y I
400 W4cct.. N.E.
- ALncertacec. Scw Mcxico 87102
- Tcu:PHo.Nc S48-S000 SINCE Ho2 February 2,1981 038%Wi]clT Mr. Alphonso A. Topp, Jr.
cre Lic sin an egistration Section U S O U UbI State of fie.< Mexico R
'O Environmental Improvement Division RADIATiGH PROTECIl0N SECTION Post Office Box 968 Santa Fe, ::" S7503
Dear Mr. Topp:
This letter constitutes the report on 1-125 radiation implant therapy at St. Joseph Hospital that you requested in your letter of December 31, 1980.
On behalf of the hospital, may I express our appreciation to you and your agency for allowing us sufficient time to conduct a
thorough investigation.
Before responding to the specific concerns raised by your letter, it would be appropriate to describe the action taken by the hospital to investigata this situation.
A thorough review of the medical records and related documents was conducted.
Then a
five-person fact finding committee, consisting of four physicians and a member of the hospital administrative staff, was jointly appointed by the Medical Staff and Administration.
The committee was asked to review all the facts concerning I-125 therapy, other forms of brachytherapy and external beam therapy at the hospital.
The committee met on ten occasions, and this report is based on the work of that ccmmittee and our censultants.
The hospital retained Charles A. Kelsey, Ph.D., Professor of Radiology at the University of New Mexico and a certified radiological physicist, to investigate the situation and compute actual dosage delivered to each
'pcticnt.
In addition, the hospital retained two radiotherapists, Don R.
- Goffinet, M.D., Associate Professor of Radiology at Stanford University, and Frank Batley, M.D., Director and Professor of P.adiation Oncology at Ohio State University, to independently review the clinical aspects of the radiation therapy service.
An independent dosimetrist, Denna M. Pooler of Stanford University, was also retained by the hospital to review the dosimetry calculations.
The hospital rade available to the committee and the independent consultants all documents, records anc other i n formation requested by them.
Although you have only requested information abcut certain cases, we are providing you with information on dosage administired to all prostatic cancer patients implanted with I-125 curing the period 'in question (Dec.
1977-July 1979).
=
ese e
a ya en***
e, Tir. Alphonso A. Topp, Jr.
February 2, 1981 Page 2 Respona'ing to the question contained in subparagraph (a), I would like to quote from Dr. Kelsey's report, which is appended to this letter.
,p j,4 i,g "t
is not a nonnal procecare to prescribe a tumor go O
E i
dose in I-125 prostate therapy.
The usual procedure brM y g:d is for the r'ysician to palpate the prostate to 5
gf 54,p 9,s dQ $(*,t estimate its volume.
On the basis of this volume' a preliminary estimate of the number and strength of 4
I-125 seeds required for the impl ant is made using joS'9 either a ncmogram or an empirical formula.
The final determination of the number of seeds to be implanted is made at the time of surgery on the basis of actual measurements of the prostate.
In almost all cases the volu ne to be irradiated corresponds to the entire prostate.
It was not the practice of the physicians to prescribe limiting doses to the bladder, rectum or other nonnal tissues."
,d
.p In response to subparagraph (b), Dr. Kelsey's calculations as to total dose delivered to each patient are found in Table II of his report.
Oh r
Rather than responding to subpcragraph (c) on a case-by-case basis as requested, we shall ' respond in a general manner with respect to all of the
- cases, since the i nformation available to us led us to conclude that essentially the same considerations applied to all of them.
g.
As explained above, it is not possible to compare " prescribed" dosed ' '
with actual dose since a dose to the prostate is not normally prescrihed in,'
- licwever, one of our consultar,ts has suggested that aUg desired dose in I-125 implant therapy is 16,000-20,000 rads to the bulk of M the prostate.
Therefore, we will concentrate on di fferences between desired dose and total dose, rather than between prescribed dose and total dose.
Two areas of concern have been identified by the investigation with respect to those cases in which total dose to the prostate exceeded the
,p" desired dose.
The first of these is the clinical judgment of theS;Wl A
radiotherapists in determining the number and strength of seeds to be "
The responsibility for making that determination, together wit i;npl a nted.
g the judgment about the need for external ceam theracy, rests with radiotherapists involved (Dcyle Simmons, M.O. and ti.J. Murrell, ". 3.).
the 3 a"'l6 g.
Secondly, it has been established that an incorrect conversion factor was utilized to convert rads-per-hour (d.ich was the manner in which tne.
L s
-i Mr. Alphonso A. Topp, Jr.
February 2, 1981 Page 3 treatment planning system expressed radiation received by the patient) to
.;/
total dose.
Those calculations were performed by the dosimetrist (Marvin f,
4 ge ennisp#
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+
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d}
able to Leavitt.
Ph.D.,
of the University of Utah.
He have not been determine how the dosimetrist initially obtained the incorrect conversion Ig factor.
Moreover, there appears to be no evidence in the patients' charts S J*
to indicate that the conversion factor was changed prior to the date of the [
last treatment.
In response to -subparagraph (d) of your letter, the external beam therapy devices have been calibrated every six months since installation.
The instruments used to calibrate the devices were calibrated in 1976, 1978, 1980 and 1981.
The records indicate that all calibrations were well within acceptable standards.
These records are available to your agency upon request.
With respect to subparagraph (d)(3), there was no " misadministration" of external beam therapy.
All external beam therapy received was within acceptable limits with respect to the dose prescribed.
Dr. Kelsey stated that he "found no problems or errors associated with the external therapy units."
The relationship of external beam therapy to total dose is outlined in Table II of Dr. Kelsey's report.
With respect to subparagraph (e) of. your letter, measures proposed to avoid the possibility of any future problems in this area include:
(1)
We are in the process of negotiating a centract with the University of flew Mexico for total radiological physics support.
(2)
A new Director of Radiotherapy, Kutub Khan, M.D., has been hired and will assume responsibilities for the department on March 1, 1931.
Brachytherapy will not be resuned' until he arrives and adequate radiological physics support is available.
The hospital has ordered a new therap in (3) manufactured by Atomic Energy of Canada, Ltd. and carheted by 4 '
General Electric Medical Systems.
It is anticipated that this'
.s
- we plan for the physics supccrt f,'
Between Maren 1 and5 new system will be installed in May 1931.
j; group from the University of New Mexico to perform an the time of the installation,
,.4 brachytherapy dosage calculations on University instrumentation. 4 'j.
3 J;;
4,.
~~
(4)
The hosoital 'is reexanining i ts 4redentialing procesDin the areas of radiology and radiotherapy and has re-emphasize'd 4 3 p cd '
pj tcC i.
j '.
J
lir. Alphonso A. Topp, Jr.
February 2,1981 Page 4 standing hospital policy of complete documentation of all items affecting patient care.
(5)
A clear line of administrative authority has been established between the Radiation Safety Officer, Radiation Safety and' Isotope Committee and Hospital Administration.
In reference to subpa'ragraph (f) revi ert of representative cases does not indicate evidence of similar systematic error in other therapeutic medalities performed at the hospital.
The referring physician of each patient has been notified by the hospital as to the actual dosage administered.
In light of the foregoing, the hospital does not request any modification 'to the Radioactive Materials License, at this time.
- However, you will be receiving in the ordinary course of business an application to add Dr. Yshan to our Radioactive Materials License.
As soon as negotiations with the University of New Mexico are completed, we will notify you of further requests for modifications to our license with respect to the physics coverage.
In the event that further pertinent information comes to our at,tention it will be made available to you.
Thank you for your cooperation.
Sincerely yours,
& \\.
isG kY Sister Celestia Koebel President SCK: 1 fv s
E Clu n.r.S A. IMI.5r.r. PnD.
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ALDCQUE.leQUE. ELV Mr.I1CO 61111 40$.29 3 2203 SUW4ARY REPORT OF C. A. KELSEY, PH.D.
Certified Radiological Physicist January 27, 1981 P'.'P. POSE OF INVESTIGATION:
a)
To determine the doses prescribed for the patients treated with I-125 seed for carcir.oma of the prostate at 5..'oseph Hospi al in the ;aried i
from 1977 to 1979.
b)
To determine the accuracy of the computer programs used ir. calculating the radiation doses to the patients.
c)
To determine the source of the factor a45 used to convert " rads per hour" to " rads at total decay".
d)
- To determine when this conversion factor was changed from 445 to 2074.
e)
To determine deses delivered to the prostate, the anterior rectal wall and the inferior bladder wall for each of the patients treated with I-125..
I f)
To determir.e the procedures actually used in the I-125 treet ents and the responsibilities of the persons involved in these procedures.
g)
To document the calibration of the external therapy devices and the
/.
instruments used in these calibrations.
h) 'To investigate other radiation therapeutic modalities at St. Joseph Hospital for similar systematic errors.
i)
To review the entire Radiation Safety program at St. Joseph Hospital for defects or deficiencies.
j)
To determine probable causes of the dosimetry errors.
j k)
To recommend measures and actions to preclude similar incidents in the i
future.
SUW4ARY OF ACTIVITIES:
Visit to University of Utah in Salt Lake City December 4 and December 11, 1980.
Review of Patient Charts.
Review and Intercomparison of I-125 computer programs to de: ermine their' accuracy.
Conference with Drs. Murrell and Simmons.
u
--q
.s.
Cre rmes rt.not e,er.s pn e nunt 313 0 CA.'t!NO RIM 07. N t.
o AL.DCQCE.ftQCT NDe* MEAICO t*111 505.293 2:e3 Kelsey 2 Calculation of doses to tumor and normal tissue volumes.
Review of External Beam procedures and calibrations. '.
Review of Radiaticn Safety Program.
FACTS:
A t eat.ent planni.ng rys em devele;ed at the '.'niversity of Utah.;as installed at St. Joseph Hospital by Dr. Dennis D. Leavitt of the University of Utah on July 21, 22, 1977.
. :. ]
Or. Leavitt visited St. Joseph Hospital December 9-11, 1978 to update the #
treatment planning system.
Three verisons of the treatment planning program were used at St. Joseph Hospital and are summarized in Table I:
j TABLE I
.J.-
Treatment Planning Programs Used at St. Joseph Hospital f/
I Version Input Output Display Format j
I mgRa eq rads /hr stars t.
II mgRa eq rads /hr diamonds
[\\h Q..'qo i 1
III mci rads diamonds Sj
..c 1 6 o'W c
No errors were made with version III because the output is given in " rads' and hvfE #.j
?
no conversion factor is required to convert from rads /hr to rads.
r.J
....e The accuracy of the program available for complete verification (III) is within
..n -
'i t e '.i acceptable limits.
Intercom; arisen of Version I and II cut;ut pi: s..ith cur.:at pecgrams in use at University of I'ew ltexico Cancer Research Treatment Center and University of Utah indicates agreement to better than 10*;.
The accuracy of the USM CRTC and University of Utah programs has been verified by independent dosimetry measurements, d
d-It is not a normal procedure to prescribe a tumor dose in I-125 prostate therapy.M y' The usual procedure is for the physician to palcate tne crostate to estimate its v g, volume. On the basis of this volume a preliminary estimate of.the number and 4l,4 strength of I-125 seeds required for the ir.slan'. is made using either a nemogram Mi or an empirical formula.
The final determination of the number of seecs to be implanted is made at the time of surgery on tr.e basis of actual measurements of the prostate.
In almost all cases the volume to be irradiated corresponds to Ine
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entire prostate.
It was not the practice of the physicians to prescribe limiting doses to the bladder, rectum or other normal tissues.
SOURCE OF ERROR IN CONVERSION FACTOR:
Versions I and II of the treatment plannin; program used s 'ridium camma fiictbr of 8.25 R-cm'/mgm-br in the calculation of dose rates. Bothversionscallforrg s
the individual seed activity t's be entered in mgm Ra eq (milligrams radium 2 a.'
e':uival ent). This is ccmon '.erminology a*d refers to hca much rsdium the seed
[,; J r.
activity is equivalent to.
The seed activity is specified by the supplier in millicuries (mci).
To convert from mci to mgm Ra eq the activity in mci must
- 3). s.
be multiplied by the ratio _ of_the. gar.ma_factots&' rag.e radiu Th
/T also be multiplied by 0.96 to convert from R to The University of Utah /
'"..n.i program used an,.Iridiu6 caba facioT of 1.7 rad-cm / mci hr.
~
The ratio of the M ***fgainmi' ractors is 0.215.
Thus a 0.fQCi I-125 seed has an activity of _.043_ [?
,W N mgm Ra eq.
When the input to the program used seed activ.ity in m;m Ra eq the,)
i output was correctly specified in rad $ per hour. To obtai% the total dose Inis
.c) dose rate (R) is multiplied by the tot i number of hours the. isotope is present.
,. 3..
Ng;a This is given in terms of the half life "by:
E h., e#
sk
<d
.m.
R exp(. 93t/T)dt y<d *c : n,' i r.i t.c..f w
Me c.u T rs.
t is
~
"U ' " ".'. Total Dosem : M * - n =. L,.. Y l.c h y
=
is
- b
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tes M is r d: sr.
- A
,A 3 ggx3xg \\
wer r
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- ..,w m! w :
sa
.m c.% rabc.g4 M
'f', c ce =c. 2 e r w;.f rca s id..e
- s
- .., *.
rke is E rThe half life of I-125 is 60 days so the correct total dose is "given by:
}ad
- v.. ws:s., h e,.,
r 's
~
u..iqCerc.) %
Total Dose 1.44x60x24xR
=
ye.t,4c.:.W.".
r[n g g.,' ;3 S:5 H' D
,g 2074xR(rads)
=
n
-n s !
a where R is the correct dose rate in rads / hours.
There is another way to cbtain the correct total dosa celivered.
If the seed activity is enterti into the program in mci the calculated dose rate R will be too high by a fact-equal to the ratio of the gamma factors.
However the correct total dose can be obtained by " Adjusting" the time to total decay by the ratio of the gam:na factors as follows:
4 Q tf g 41(,(DSv&T* 5:N * ' '..
5 C= 2074 x.
5 x R*
=445:x R* /
,e,g 4.( j
,.7 e
&s M "'O *
,;.w
/
. H, 3 t.a
- w... m..- ! : !h
$m.d This would be an unustal approach becauseltne crocran reouestsd the seed activity'
-.w' '( bin mcm_Ra eo.
Note that the correct conve'rsion factor frcm cose rate to total
~*
dose depenas on whether the seed activity is entered into the program as mci or J ',,
0.,s. cgm Ra-eq.
, s%,;;-)
' '... ',f! The treatment planning technician at St. Jcse;n Hospital changed the seed y f Jactivity from mci to acm Ra eq as requestec by tne prcgram.
The precram calculated
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A i
a
<m.
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i*
Cn.sn!.ns A. T, c:.enY. PnD.
Cteerstie s Itas,suc,.asc.s Pus estsst 3110 CANbO laCA!. CT. N.E.
305 293 2293 ALBCQCLDQUE. NEW Y.111CO sitt1 Kelsey 4 e
E's
/ f the correct dose rate. Unfortunately the technician used the factor 445 to convert dose rate in rads per hour to dose at total decay.
This resulted in K./.g factor of 2074/445 doses reported to the radiotherapists which were too low by a(4.7). -In som gn V j' a dose to the prostate up to the " desired" range or increased the strength andThe desired
.u.O.ar of I-125 seed in future implants.
'in the range 16,0 o_20.000 r (s_ to the entire prostate. Maximum doses to the f?
prostate are
)fficult to calculate accurg'lduetohighdosesintheimmediate
.N d bR thir."y of de in:i /Eal seeds? -
' f w e Mk 4 <.p c n.<:y
. sr.s.
I was not able to determine whether or when the conversion factor was changed
..,J ', t r' There is no evidence in the patient charts to indicate that#,..ce
from 445 to 2074 A'*'
the conversion factor was changed before the last patient was treated.
My best estimate of the doses to the prostate, anterior rectal wall and inferior bladder wall'from the I-125 implant and external beam are contained in Table II.
The procedures employed in the I-125 therapy have been described above. The radiotherapists were responsible for determining the number and activity of the seeds to be implanted.
The treatment planning technician was responsible for obtaining adecuate localization radiographs and accurately inputing seed locations into the computer.
The radiotherapists were responsible for deciding whether and how much external radiation was required.
The instruments used to calibrate the external beam therapy devices were calibrated in 1976, -78, 80 and 1981.
These calibrations agreed to within 0.2"..
The therapy units have been calibrated at six month intervals since their installation.
I found no problems or errors associated with the external therapy units.
I have reviewed representative samples of the other radiation therapeutic modalities
, b,, oin 'use at St. Joseph Hospital for similar systematic errors and do not find cny
.T evidence of such errors.
I have reviewed the Radiation Safety program at St., Joseph Hospital and finc that M [.
- M it is acceptable and ccmpares favorably with other programs in similar hospitals,
- g., '.
I found no shortcomings or deficiencies.
V'.
.,!I believe the fundamental cause of these incidents was a lack of communicatien
' ".' D e
~
'. 'g]* i' :between the developers of the treatment planning computer program and its users iccupied with' a lack of experience in 1-125 implants on the part of tne radio-
\\v.?
itherapists and technician.
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.y 7," y I' recommend:
t e.. e <. (...o. d c. :4.v W.
A.
. /.. g'-
- 1).Tha' a certified radiological physicist be added to tne staff and be given J
l responsibility for dosimetry and trea. en planning for all racia.;cn therapy patients.
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+1 CHAnLT.S A. E CLSEY. PH D.
Ce vmien na n..c.. 5 russiust 3110 CAltl. O RrJL CT. N.E.
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305 293 2208 AL13CQCrJiQUE. hCW Sua2CD 47133 Kelsey 5
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- 2) That any changes in computer programs, equipment or procedures used ind ','. 5. '";;,
the treatment of. patients be completely documented.
,rl' 3 '. "9 g,.
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- 3) That weekly checks of every radiation therapy patient be instituted.
J. s g. * *, /,0 +
- 4) Th:t a tro-ta::nt su=.ary be generated for every patient completing radiation therapy.
That a ci-.r Mne Of ad.-inistrative aut.crity between the t:'iation 5)
Safety Officer, the Hospital Radiation Safety Cc=mittee and the Hospital.
i Administration be established.
That clear procedures of reviewing the training and experience of physicians 6) authorized to use ionizing radiation on ht, mans be established and periodically reviewed.
If you have any questions about this report or other matters please contact me, h
r Charles A. Kelsey. P.D.
Certified Radiological Physicist I
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