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Bone scan findings (using OtmTc.stanuaus pyrophosphate) in five patients with. diffuse metastatic carcinoma of the axial skeleton are reviewed Although there were few visually recognizable asymmetries of tracer localization, the diffuse involvement was diagnosed through abnormally elevated counting rates in the axial skeleton, decreased visualization of the kidneys, and faint or absent visualization of the appen dicular skeleton.
Since the introduction of technetium-labeled phos
phate compounds, detection of bony abnormalities
by bone scanning has improved (1—5).Because of
the greater sensitivity of bone scans, Pistenma et al
(6) suggested that these scans should replace the
conventional radiographic skeletal survey as a means
of detecting early metastatic bone disease. However, Thrupkaew et al (7) and Frankel et al (8) recently described normal-appearing bone scans in patients
with diffuse metastatic disease of the axial skeleton
which was demonstrable by x-ray. Recognition of
these false-negative results is obviously important.
We have evaluated five patients who had diffuse
metastases to the axial skeleton which were not oh
vious on initial examination of their bone scans.
Here we discuss the factors that provided clues to
the correct interpretation of these studies.
MATERIALS AND METHODS
Five male patients were studied: four with adeno
carcinoma of the prostate and the fifth with a transi
tional cell carcinoma arising in the renal pelvis. All
were studied with a 5-in. dual-probe rectilinear scan
ner (Ohio-Nuclear Model 84, Solon, Ohio) 3 hours
after the intravenous administration of 15 mCi of
øOmTc..stannous pyrophosphate (Mallinckrodt, St.
Louis, Mo.). Minified images (5 : 1) were obtained,
and a count density of 360 counts/cm2, with ½-in.
line spacing, was used to determine scan speed.
Counting rates over the sternum and thoracic spine
normally fell between 50,000 and 80,000 cpm. The
Received Sept. 9, 1975; revision accepted Nov. 4, 1975. For reprints contact: L. R. Witherspoon, 1514 Jefferson Highway, New Orleans, La. 70121.
@ A R B R
HG. 1. (A)Normalposteriorbone scan of 55-year-oldman
with carcinoma of prostate. Counting rate is 60,000 cpm over spine, 50,000 cpm over sternum.(B) Posterior scan on same patient employing contrast enhancement of 2. Note false accentuation of axial skeletonand loss of appendicular skeletal image.
Volume 17, Number 4 253
BONE SCAN PATTERNS OF PATIENTS
WITH DIFFUSE METASTATIC CARCINOMA
OF THE AXIAL SKELETON
Lynn R. Witherspoon, Lawrence Blonde, Stanton E. Shuler, and Donald B. McBurney
Ochsner Medical Center, New Orleans, Louisiana
No.PhysicalLaboratoryAge/SexPat. Initial complaint examinationfindings (^) Diagnosis Treatment Metastases No abnormality Radiation
AsymmetricThoracic.spineSternumactivity inAppendicularcountingratecountingrateaxial skeletonskeletal activity Renalactivity (cpm)(cpm)
WITHERSPOON, BLONDE, SHULER, AND MCBURNEY
TABLE1. CLINICALDATA FOR FIVE PATIENTSWITH FALSE-NEGATIVEBONE SCANS
1 771MBackache
(Lt ne- Elevated acid Adenocarci phrectomy 5 yrs phosphatase, noma pros earlier for ca anemia, ESR tate by kidney) 125 biopsyBlastic,
ii hip, and lumbar spine
68/MUrinary
obstruction Enlarged rock- Elevatedacid Adenocarci (Rt nephrectomy hard prostate phosphatase noma pros 12 yrs earlier and LDH, tate (poorly for calculi) anemia differenti ated)TURP,
estro gen, orchi ectomyPelvic
and spine3 thoracic
58/MBloody
ejaculate, Induration in Elevated acid Adenocarci backache prostate phosphatase noma pros and LDH, ane- tate (poorly mia, ESR33 differenti ated)TURP,
orchi ectomyPerineural
lym phatic, blastic pelvic
52/MAsymptomatic
Hypertension,ten- Elevatedacid Ca It renal dernessin phosphatase, pelvis sacroiliac areas anemia, ESR 113Nephrectomy,
radiation, chemother apyRibs,
pelvis, thoracic, spine5 lumbar
69/MLow
bock pain, Mass rt prostate, Elevated acid Ca prostate weight loss hepatomegaly, phosphatase, (Prostatectomy decreased LDH,SGOT, 7 yrs earlier breath sounds and uric acid; for ca) at lung base, anemia; ESR pleural effusionOrchiectomy,
estrogensPerineural,blastic in ribs, pelvisAbbreviations: spine,
ca—cancer;ESR—erythrocytesedimentation rate (Westergren method); transurethral resection of prostrate; SOOT—serumglutamic oxaloacetic transaminase.LDH—Iacticdehydrogenase;
TURP
TABLE2. SUMMARYOF FIVE FALSE-NEGATIVEBONE SCANS
Normal (Fig.1)NoNormalNormal60,00050,000Case 2)NoDecreasedDecreased110,000120,000Case1 (Fig. 2RibsDecreasedDecreased100,000100,000Case 3RibsDecreasedAbsent160,00080,000Case 4Ribs,spineAbsentAbsent170,000150,000Case 5 (Fig. 3)NoDecreasedDecreased150,000100,
24L low-energy collimators were used. Spectrometer
baseline was set at 120 keY, with a 40-keV window.
A background erase setting of 3 was used. The pic
ture intensity control was depressed with both the
anterior and posterior probes recording similar
counting rates (i.e., 70,000 cpm) over the sternum and thoracic spine. Whenever these areas were in volved by disease, the picture intensity control was
depressed with the probes positioned wherever equal
counting rates of about 70,000 cprn could be oh
tamed.
RESULTS
Clinical data for the five patients studied are pre
sented in Table 1. The bone scan findings are sum
marized in Table 2. Figure 1A shows a normal pos
terior bone scan for comparison with the abnormal
studies, and Fig. lB is a scan of the same patient
taken with a contrast enhancement setting of 2 (Ohio
Nuclear Model 84). Figures 2 and 3 show the bone
scans and radiographs of two representative cases
(Nos. 1 and 5 ). Abnormal findings in these patients were (A) elevated counting rates from the spine and
254 JOURNAL^ OF NUCLEAR MEDICINE
WITHERSPOON, BLONDE, SHULER, AND MCBURNEY
.. -@
FIG.3. (A)Bonescansof 69-year-oldmanwith
carcinoma of prostrate showing left humeral lesion. Diffuse involvement of axial skeleton was suggested by counting rate of 150,000 cpm over sternum (usually 50,000—70,000and decreased visualization of appendicu lar skeleton and kidneys (B) Radiograph showing diffuse skeletal involvement.
A
Ant Post
obvious when numerous lesions produce marked
asymmetry in tracer localization, as reported by Sy
et al (9), or it may only provide a clue to the dif fuse disease, as in our five patients. Although this was a consistent finding in our cases, the renal im
ages appear normal in the case reported by Frankel
et al (8).
Either contrast enhancement or background sub
traction will result in loss of the appendicular images
(Fig. 1B ). Neither (unless employed at high levels)
will result in the loss of normal renal images. Back
ground subtraction or enhancement of bone should
be employed sparingly, if at all, because of the re
sultant suppression of potentially useful information.
To avoid errors in interpreting bone scans in pa
tients with diffuse disease of the axial skeleton, count ing rates over survey areas in the skeleton must be recorded at the time the scans are obtained. Know
ing the usual counting rates in patients without bone
disease scanned on rectilinear scanners and the nor
mal exposure times for images obtained on station
ary imaging devices is essential. Markedly elevated counting rates over the spine and anterior chest wall
should suggest diffuse disease of the axial skeleton.
CONCLUSION
In summary, abnormally elevated counting rates
in the axial skeleton, decreased kidney visualization, and faint or absent visualization of the appendicular
skeleton should suggest the possibility of diffuse
axial-skeletal disease even when asymmetries in
tracer distribution are minor. These findings should be sought in patients with those malignancies which commonly metastasize to bone (breast, prostate,
lung), particularly if bone scanning has replaced
routine radiographic skeletal surveys as the primary, means of detection of bony abnormalities in such patients.
REFERENCES
1. SUBRAMANIAN 0, MCAFEE JG, BELL EG, et al: 9mTcLabeled polyphosphate as a skeletal imaging agent. Radiology102:701—704, 1972
256 JOURNAL OF NUCLEAR MEDICINE
DIAGNOSTIC NUCLEAR MEDICINE
2. CAsmoNovo FP, CALLAHAN RJ : New bone scanning agent: “mTc-labeled l-hydroxy-ethylidene-1,I-disodium phos phonate. I Nuci Med 13: 823—827, 1972 3. SILBERSTEIN EB, SAENGEREL, TOFE AJ, Ct al: Imaging of bone metastases with °‘mTc-Sn-EHDP(diphosphonate), “F,and skeletal radiography. Radiology 107: 55 1—555,
- KRISHNAMURThYGT, WALSHCF, SHOOPLE, Ct al: Comparison of “mTc-polyphosphateand ‘IF.II. Imaging. _JNuclMed 15:837—843, 1974
- ECKELMANWC, REBARC, KUBOTAH, et al: ‘°mTc_ pyrophosphate for bone imaging. J Nuci Med 15: 279—283, 1974
- PISTENMADA, MCDOUGALLIR, KRISSJP: Screening
for bone metastases.Are only scans necessary?IAMA 231:
46—50, 1975
7. THRUPKAEWAK, HENKINRE, AUNGCHOYEK, Ct al: False negative bone scans in disseminated metastatic disease. **_Radiology113:383—386, 1974
- FRANKEL RS, JOHNSON KW, MABRY JJ, et al : “Normal―_** bone radionuclide image with diffuse skeletal lymphoma. A case report. Radiology 1 1 1 : 365—366, 1974
- SY WM, PATEL D, FAUNCE H: Significance of absent
or faint kidney sign on bone scan. I Nuci Med 16: 454—
Volume 17, Number 4 257
THE SOCIETY OF NUCLEARMEDICINE
23rd ANNUAL MEETING
June 8—i1, 1976 Dallas Convention Center Dallas, Texas
FIFTH CALL FOR ABSTRACTSFOR SCIENTIFICEXHIBITS
The ScientificExhibitsCommitteewelcomesthe submissionof abstractsfor the display of scientific exhibits for the 23rd Annual Meeting of the Society of Nuclear Medicine. This year there will be three categoriesof exhibits:1) regular and small viewbox; 2) residentsand fellows; and 3) jiffy exhibitscon taming materials presented in scientific papers. Regularexhibitsmay be large or small, free standingor illuminatedby viewbox, and offer a means whereby attendeescan take their time to view the material, assimilatingand digesting the information at their own pace. The special residentsand fellows category is designed to encourage physicianswho are training in the field of nuclear medicine to participate in the national meeting. The jiffy exhibits, whose introductionlast year was so successful,offer an opportunityfor thosepresentingscientificpapers to presentthe salient features of their paper in exhibit format so that participants in the meeting can review the data at their leisure. Scientific exhibits award: The Society is pleased to announce the presentationof awards in the following categories: 1) clinical nuclear medicine; 2) instruction; 3) biophysics and instrumentation; 4) residents and fellows exhibits. In each category there are gold, silver, and bronze medal awards for out standing exhibits. Judging is based on scientific merit, originality, display format, and appearance. Judg ing will occur on the first full meeting day.
Abstract format: Abstractsmustbe submittedon a specialabstractform for scientificexhibitswhich
is available from the Societyof Nuclear Medicine, 475 Park AvenueSouth,New York, New York 10016.
Abstract deadline—April 1, 1976.
Abstract deadline for Jiffy Zibits—May 1, 1976. Send all abstract forms to: H. William Strauss,M.D. Division of Nuclear Medicine and Radiation Health The Johns Hopkini Medical Institutions 615 North Wolfe Street Baltimore, Maryland 21205
