- Email: [email protected]
CT of calcified bladder masses
0730-4862/X5 $3.00+ 0.00
Compufrrizvd Radio/. Vol. 9, No. 3, pp. 181&184, 1985 Printed III the U.S.A.Allrights reserved
Copyright
CT OF CALCIFIED
BLADDER
\(‘s 1985 Pergamon
Press Ltd
MASSES
GERALD A. L. IRWIN, RONALDCRAIG and PAUL NOVOTNY Department
of Radiology,
Nassau
County
(Received 26 September
Medical Center, 2201 Hempstead NY 11554. U.S.A.
Turnpike,
1984; received for publication 7 December
East Meadow.
1984)
Abstract-Calcifications observed in bladder lesions are seen on plain films with an incidence of 0.5P7.0”,,,. Four cases of calcification were noted on CT in 38 consecutive bladder scans (10.5%). Calcifications were noted both on the surface, and within the lesions. One of the cases with malakoplakia had calcification. This has not been reported to date. With CT, it is expected that calcification in bladder lesions will be found with increasing incidence, and should be looked for. Bladder
lesions
Bladder
calcifications
CT of bladder
lesions
INTRODUCTION The presence of calcification in epithileal tumors of the bladder during excretory urography is a well known phenomenon. We have recently encountered 4 cases of calcification in bladder lesions, visualized on computed tomography (CT). No previous reports of this finding on CT was available, and we thus wish to document our experience. METHODS
AND
MATERIALS
Thirty-eight consecutive patients who had CT for evaluation of bladder lesions from April 1981 through June 1983, were reviewed. Most of these examinations were done for staging bladder neoplasm. CT scans were done with no contrast in the bladder. When possible, the patient is asked to drink fluids to fill his bladder and not to void. When IV contrast was used, the scans were started at the base of the bladder and proceeded cephalad, before the bladder was filled with contrast. All patients received oral contrast (2% powdered Hypaque in orange juice). Usual studies consisted of 1 cm sections through the pelvis and 2 cm through the region of the abdomen, stopping at the diaphragm The scans were reviewed and additional scans taken as deemed necessary, RESULTS Four of the patients had easily visible calcification of the bladder masses seen on CT (10.5%). One patient had calcification of a tumor which disappeared after cystoscopic resection, but reappeared when the tumor recurred 14 months later. Only 2 patients had visualization of the tumor calcifications present on routine scout films prior to intravenous urography. In three patients, the main calcifications seemed to be on the surface of the lesion, but two also had fine calcifications within the bulk of the mass. In the two remaining cases, the calcifications were scattered within the lesion. The clinical information for these cases is seen in Table 1.
Table Patients C.C. 66M SW.
81 M
1.1. 61 M P.Y. 69 M
Diagnosis Transitional cell carcinoma grade I I - 1I I class 2B Transitional cell carcinoma Malakoplakia Papillary transitional
I
Status of therapy when calcification noted
cell
Calcification seen on plain film CT
Chemo +
Rad _
_
+
_
_
_
+
_ _
_ +
_ _
+ +
181
Type/location
of calcifications
Curvilinear calcifications on surface Curvilinear on surface of tumor mass and within the mass Surface and within mass Within tumor mass
182
GERALD A. L. IRWIN (11ul.
CASE
REPORT
Patient C.C. is a typical example of our findings. He was a 66-yr-old male who presented with hematuria. Excretory urography showed a polypoid mass in the bladder which was then biopsied with a diagnosis of “transitional cell CA of the bladder.” He was treated with local cystoscopic resection. The tumor recurred 14 months later. A CT scan at the time of the initial presentation [Fig. l(a)] demonstrated extensive calcification on the surface of the tumor with no involvement beyond the bladder wall. The patient was treated with chemotherapy and local resection of the tumor. An interval scan showed bladder lesions without calcification [Fig. l(b)], but a repeat scan at the time of recurrence again demonstrated calcification on the tumor surface [Fig. I(c)].
Cc)
(b)
Fig. 1. (a) Transitional cell carcinoma with surface calcifications. (b) Interval scan two months later after fulguration shows thickened wall and no calcification. Biopsies showed no tumor. (c) Tumor recurred four months after (b), and again surface calcification is noted.
DISCUSSION The incidence of calcification within bladder neoplasms noted on routine films at the time of excretory urography is noted to be between 0.5 and 7% ‘[l, 2,4]. In our very limited series of 38 consecutive cases the incidence of calcification in bladder lesions was lO.S’k. This higher percent is not surprising when the superior ability of CT to discriminate calcifications not noted on plain film is considered. CT can detect density differences of 0.5%, while at least 5% difference is needed for plain film detection. A higher incidental finding of calcification in bladder tumors with CT should be expected, but cannot approach the 15% demonstrated on pathologic specimens [4]. The patient with calcification in malakoplakia (Fig. 2), is unusual and the first report of this finding that we know of [3]. While malakoplakia is not considered a tumor, but a response to chronic infection, we have included it in our series because it may present on IVP and CT as a possible bladder tumor.
CT of calcified
bladder
masses
183
Fig. 2. A 61-yr-old male with biopsy proven malakoplakia. CT shows Foley catheter and generalized thickening of the bladder wall. Calcifications noted on the surface and the depths of the lesion.
We feel our method of imaging the bladder utilizing retained urine as a contrast agent is an excellent method of visualizing the bladder wall. The urine is usually diluted and of a lower density than the bladder wall, which allows for differentiation of both the inner and outer wall. Thickness of the wall can be measured and changes in contour easily seen. When the bladder is imaged full of contrast excreted during intravenous infusion, “overblooming” is evident, which makes evaluation of the outer wall poor, and the inner wall is often not seen at all. If intravenous contrast is to be used, imaging should begin at the bladder and move cephalad to resolve this problem, as the bladder will be imaged before it fills with contrast. Other methods of evaluating the bladder wall using air, or liquid fatty material have been used, however, we feel no need to use other contrast agents than the patient’s own urine. The differential diagnosis for calcifications seen on CT in a bladder lesion should include schistosomiasis, where this calcification will be linear, lying within the wall of the bladder, and not localized to one section of the bladder as in tumor calcification. Calcification may also occur in necrotic tissue, post-radiation therapy, in severe infectious cystitis, and in tuberculosis. Because of the variety of forms and shapes of the calcification in our four patients, CT will be probably not able to use the shape or distribution of the calcification to distinguish benign from malignant lesions. Our patients had calcification both on the surface as well as within the masses. This is of no help in making a differential diagnosis when used alone as a criteria. Spread of a lesion into the perivesical fat and adenopathy are the only reliable findings suggestive of a malignant lesion.
CONCLUSION (1) Calcifications associated with bladder lesions can be seen on CT with a higher frequency than on plain film (10.5’79 in our series. (2) CT may not be able to distinguish benign from malignant lesions by utilizing the presence or absence nor the distribution of calcification alone. (3) CT findings in a case of malakoplakia of the bladder, with calcification, is reported. SUMMARY The presence of calcification in bladder lesions seen on plain films and excretory urograms is well known. We recently encountered four interesting cases of calcification seen on CT studies and a review of 38 consecutive cases showed an incidence of 10.5% in our CT lesions. A description of these cases and the calcification is part of this report. One of the interesting cases was a patient with malakoplakia who had calcification within the tumor. To the best of our knowledge, the findings of calcifications in malakoplakia has not been reported to date. With the increased ability of CT to ascertain density discrimination, it is expected that calcification bladder lesions will be found with increasing frequency and should be looked for by the radiologist.
84
GERALDA. L. IRWIN rf crl
I. S. Miller and R. Pfister, Calcification in uroepithelial tumors of the bladder, Am. J. Roentg. 121, 827-831 (1974). 2. H. Braband, Incidence of urographic findings in tumors of urinary bladder, Br. J. Radiol. 34, 625-629 (1961). 3. B. M. Epstein, V. Pate1 and P. Porters, CT appearance of bladder malokoplakia, J. Comput. assist. Tomogr. 7, 541-543 (1983). 4. H. Podak et al., Diagnostic considerations of urinary bladder wall calcification, Am. J. Roenfg. 136, 791-797 (1981). About the Aufhor-GERALD A. L. IRWIN received his M.D. and C.M. degree from Queens University, Kingston, Ontario in 1955. Internship and residency in Diagnostic Radiology was done at Nassau County Medical Center. Dr Irwin is Chairman of the Department of Radiology at Nassau County Medical Center and Professor of Radiology at State University of New York at Stony Brook. He is a Fellow of the American College of Radiology. About the Author-RONALD C. CRAIGattended Syracuse University where he received his Bachelor of Science
degree in 1973. He continued post graduate studies at Syracuse University and C. W. Post Center Graduate Schools in the field of Medical Biology. His medical studies continued at the Universidad Autonoma de Guadalajara, Mexico where he obtained a diploma in Medicine and Surgery. Post graduate medical training consisted of a one year supervised clinical internship under the auspices of the SUNY School of Medicine at Stony Brook; a residency in Diagnostic Radiology at Nassau Hospital, Mineola; and a fellowship in Computed Tomography and Ultrasound at Nassau County Medical Center. Presently, he is employed in private practice. L. NOVOTNY received his M.D. degree from New York Medical College in 1976. He did his residency training in Diagnostic Radiology at the Nassau County Medical Center since 1980 and is currently the Director of Ultrasound/Body CT. He has an appointment as Assistant Professor of Clinical Radiology at the State University of New York at Stony Brook and is a member of the Radiological Society of North America, as well as the American Roentgen Ray Society.
About the Author-PAUL
Compufrrizvd Radio/. Vol. 9, No. 3, pp. 181&184, 1985 Printed III the U.S.A.Allrights reserved
Copyright
CT OF CALCIFIED
BLADDER
\(‘s 1985 Pergamon
Press Ltd
MASSES
GERALD A. L. IRWIN, RONALDCRAIG and PAUL NOVOTNY Department
of Radiology,
Nassau
County
(Received 26 September
Medical Center, 2201 Hempstead NY 11554. U.S.A.
Turnpike,
1984; received for publication 7 December
East Meadow.
1984)
Abstract-Calcifications observed in bladder lesions are seen on plain films with an incidence of 0.5P7.0”,,,. Four cases of calcification were noted on CT in 38 consecutive bladder scans (10.5%). Calcifications were noted both on the surface, and within the lesions. One of the cases with malakoplakia had calcification. This has not been reported to date. With CT, it is expected that calcification in bladder lesions will be found with increasing incidence, and should be looked for. Bladder
lesions
Bladder
calcifications
CT of bladder
lesions
INTRODUCTION The presence of calcification in epithileal tumors of the bladder during excretory urography is a well known phenomenon. We have recently encountered 4 cases of calcification in bladder lesions, visualized on computed tomography (CT). No previous reports of this finding on CT was available, and we thus wish to document our experience. METHODS
AND
MATERIALS
Thirty-eight consecutive patients who had CT for evaluation of bladder lesions from April 1981 through June 1983, were reviewed. Most of these examinations were done for staging bladder neoplasm. CT scans were done with no contrast in the bladder. When possible, the patient is asked to drink fluids to fill his bladder and not to void. When IV contrast was used, the scans were started at the base of the bladder and proceeded cephalad, before the bladder was filled with contrast. All patients received oral contrast (2% powdered Hypaque in orange juice). Usual studies consisted of 1 cm sections through the pelvis and 2 cm through the region of the abdomen, stopping at the diaphragm The scans were reviewed and additional scans taken as deemed necessary, RESULTS Four of the patients had easily visible calcification of the bladder masses seen on CT (10.5%). One patient had calcification of a tumor which disappeared after cystoscopic resection, but reappeared when the tumor recurred 14 months later. Only 2 patients had visualization of the tumor calcifications present on routine scout films prior to intravenous urography. In three patients, the main calcifications seemed to be on the surface of the lesion, but two also had fine calcifications within the bulk of the mass. In the two remaining cases, the calcifications were scattered within the lesion. The clinical information for these cases is seen in Table 1.
Table Patients C.C. 66M SW.
81 M
1.1. 61 M P.Y. 69 M
Diagnosis Transitional cell carcinoma grade I I - 1I I class 2B Transitional cell carcinoma Malakoplakia Papillary transitional
I
Status of therapy when calcification noted
cell
Calcification seen on plain film CT
Chemo +
Rad _
_
+
_
_
_
+
_ _
_ +
_ _
+ +
181
Type/location
of calcifications
Curvilinear calcifications on surface Curvilinear on surface of tumor mass and within the mass Surface and within mass Within tumor mass
182
GERALD A. L. IRWIN (11ul.
CASE
REPORT
Patient C.C. is a typical example of our findings. He was a 66-yr-old male who presented with hematuria. Excretory urography showed a polypoid mass in the bladder which was then biopsied with a diagnosis of “transitional cell CA of the bladder.” He was treated with local cystoscopic resection. The tumor recurred 14 months later. A CT scan at the time of the initial presentation [Fig. l(a)] demonstrated extensive calcification on the surface of the tumor with no involvement beyond the bladder wall. The patient was treated with chemotherapy and local resection of the tumor. An interval scan showed bladder lesions without calcification [Fig. l(b)], but a repeat scan at the time of recurrence again demonstrated calcification on the tumor surface [Fig. I(c)].
Cc)
(b)
Fig. 1. (a) Transitional cell carcinoma with surface calcifications. (b) Interval scan two months later after fulguration shows thickened wall and no calcification. Biopsies showed no tumor. (c) Tumor recurred four months after (b), and again surface calcification is noted.
DISCUSSION The incidence of calcification within bladder neoplasms noted on routine films at the time of excretory urography is noted to be between 0.5 and 7% ‘[l, 2,4]. In our very limited series of 38 consecutive cases the incidence of calcification in bladder lesions was lO.S’k. This higher percent is not surprising when the superior ability of CT to discriminate calcifications not noted on plain film is considered. CT can detect density differences of 0.5%, while at least 5% difference is needed for plain film detection. A higher incidental finding of calcification in bladder tumors with CT should be expected, but cannot approach the 15% demonstrated on pathologic specimens [4]. The patient with calcification in malakoplakia (Fig. 2), is unusual and the first report of this finding that we know of [3]. While malakoplakia is not considered a tumor, but a response to chronic infection, we have included it in our series because it may present on IVP and CT as a possible bladder tumor.
CT of calcified
bladder
masses
183
Fig. 2. A 61-yr-old male with biopsy proven malakoplakia. CT shows Foley catheter and generalized thickening of the bladder wall. Calcifications noted on the surface and the depths of the lesion.
We feel our method of imaging the bladder utilizing retained urine as a contrast agent is an excellent method of visualizing the bladder wall. The urine is usually diluted and of a lower density than the bladder wall, which allows for differentiation of both the inner and outer wall. Thickness of the wall can be measured and changes in contour easily seen. When the bladder is imaged full of contrast excreted during intravenous infusion, “overblooming” is evident, which makes evaluation of the outer wall poor, and the inner wall is often not seen at all. If intravenous contrast is to be used, imaging should begin at the bladder and move cephalad to resolve this problem, as the bladder will be imaged before it fills with contrast. Other methods of evaluating the bladder wall using air, or liquid fatty material have been used, however, we feel no need to use other contrast agents than the patient’s own urine. The differential diagnosis for calcifications seen on CT in a bladder lesion should include schistosomiasis, where this calcification will be linear, lying within the wall of the bladder, and not localized to one section of the bladder as in tumor calcification. Calcification may also occur in necrotic tissue, post-radiation therapy, in severe infectious cystitis, and in tuberculosis. Because of the variety of forms and shapes of the calcification in our four patients, CT will be probably not able to use the shape or distribution of the calcification to distinguish benign from malignant lesions. Our patients had calcification both on the surface as well as within the masses. This is of no help in making a differential diagnosis when used alone as a criteria. Spread of a lesion into the perivesical fat and adenopathy are the only reliable findings suggestive of a malignant lesion.
CONCLUSION (1) Calcifications associated with bladder lesions can be seen on CT with a higher frequency than on plain film (10.5’79 in our series. (2) CT may not be able to distinguish benign from malignant lesions by utilizing the presence or absence nor the distribution of calcification alone. (3) CT findings in a case of malakoplakia of the bladder, with calcification, is reported. SUMMARY The presence of calcification in bladder lesions seen on plain films and excretory urograms is well known. We recently encountered four interesting cases of calcification seen on CT studies and a review of 38 consecutive cases showed an incidence of 10.5% in our CT lesions. A description of these cases and the calcification is part of this report. One of the interesting cases was a patient with malakoplakia who had calcification within the tumor. To the best of our knowledge, the findings of calcifications in malakoplakia has not been reported to date. With the increased ability of CT to ascertain density discrimination, it is expected that calcification bladder lesions will be found with increasing frequency and should be looked for by the radiologist.
84
GERALDA. L. IRWIN rf crl
I. S. Miller and R. Pfister, Calcification in uroepithelial tumors of the bladder, Am. J. Roentg. 121, 827-831 (1974). 2. H. Braband, Incidence of urographic findings in tumors of urinary bladder, Br. J. Radiol. 34, 625-629 (1961). 3. B. M. Epstein, V. Pate1 and P. Porters, CT appearance of bladder malokoplakia, J. Comput. assist. Tomogr. 7, 541-543 (1983). 4. H. Podak et al., Diagnostic considerations of urinary bladder wall calcification, Am. J. Roenfg. 136, 791-797 (1981). About the Aufhor-GERALD A. L. IRWIN received his M.D. and C.M. degree from Queens University, Kingston, Ontario in 1955. Internship and residency in Diagnostic Radiology was done at Nassau County Medical Center. Dr Irwin is Chairman of the Department of Radiology at Nassau County Medical Center and Professor of Radiology at State University of New York at Stony Brook. He is a Fellow of the American College of Radiology. About the Author-RONALD C. CRAIGattended Syracuse University where he received his Bachelor of Science
degree in 1973. He continued post graduate studies at Syracuse University and C. W. Post Center Graduate Schools in the field of Medical Biology. His medical studies continued at the Universidad Autonoma de Guadalajara, Mexico where he obtained a diploma in Medicine and Surgery. Post graduate medical training consisted of a one year supervised clinical internship under the auspices of the SUNY School of Medicine at Stony Brook; a residency in Diagnostic Radiology at Nassau Hospital, Mineola; and a fellowship in Computed Tomography and Ultrasound at Nassau County Medical Center. Presently, he is employed in private practice. L. NOVOTNY received his M.D. degree from New York Medical College in 1976. He did his residency training in Diagnostic Radiology at the Nassau County Medical Center since 1980 and is currently the Director of Ultrasound/Body CT. He has an appointment as Assistant Professor of Clinical Radiology at the State University of New York at Stony Brook and is a member of the Radiological Society of North America, as well as the American Roentgen Ray Society.
About the Author-PAUL