Sonographic Diagnosis of Ureteral Tumors

Transcription

1 Sonographic Diagnosis of Ureteral Tumors Irith Hadas-Halpern, MD, micur Farkas, MD, Michael Patlas, MD, Ibrahim Zaghal, MD, Shoshana Sabag-Gottschalk, MD, Drora Fisher, MD We present our experience with transabdominal ultrasonographic diagnosis of ureteral tumors. During the years 1989 to 1998, 16 patients were diagnosed as having ureteral tumors. These patients were referred for sonographic examination for evaluation of hematuria (seven patients) or flank pain (four patients) or for follow-up screening in patients who were asymptomatic but at high risk for transitional cell carcinoma because of known past bladder tumor (five patients). Ten of these patients underwent intravenous urography examination, three patients had retrograde pyelography, and 11 patients underwent CT scanning. Ultrasonography revealed the ureteral tumors in all 16 patients, which appeared as hypoechoic intraluminal soft tissue. Three tumors were localized in the upper ureter, four in the middle ureter, and nine in the distal ureter. The degree of ureterohydronephrosis was minimal (two cases), mild (five cases), moderate (eight cases), or severe (one case). Eleven tumors caused local widening of the ureteral diameter. On intravenous urography, four patients had a nonfunctioning kidney, three patients had unexplained ureterohydronephrosis, and three patients showed ureteral filling defects, of which only two had irregular contours. On retrograde pyelography, two patients had filling defects (one of which with smooth margins), and one had a truncated ureter. On CT the tumor was clearly demonstrated in only seven patients. We found that ultrasonography can be a useful diagnostic tool in the workup of ureteral tumors. KEY WORDs: Ureter, tumors; Tumors, ureteral; Transabdominal sonography. Transabdominal ultrasonography is commonly used for evaluation of the urinary ultrasonography has heretofore been considered to wide range of pathologic conditions. 1 However, tract and can be employed to diagnose a be of limited value for diagnosing pathologic ureteral conditions. 1,2 The diagnostic imaging modalities considered most effective for the ureter are IVU and antegrade and retrograde pyelography. 2 4 IVU depends on kidney function, and although it is able REVITIONS to demonstrate a filling defect, it is not always possible to accurately characterize the nature of the defect. IVU, Intravenous urography; TCC, Transitional cell carcinoma; CT, Computed tomography Inability to define the exact nature of a filling defect also restricts the usefulness of antegrade and retrograde pyelography. 5 Transabdominal ultrasonography is almost universally available, is noninvasive, requires no injection of contrast agent, and is independent of kidney Received September 6, 1998, from the Departments of Radiology (I.H.-H., M.P., I.Z., D.F.), Urology (.F.), and Pathology (S.S.-G.), Shaare Zedek Medical Center, Jerusalem, Israel. Revised manuscript function; hence we prefer this modality for initiating accepted for publication June 10, investigation of urinary symptoms. ddress correspondence and reprint requests to Irith Hadas- Halpern, MD, Department of Radiology, Shaare Zedek Medical We present our experience with transabdominal Center, PO ox 3235, Jerusalem 91031, Israel. ultrasonography in diagnosing ureteral tumor at all 1999 by the merican Institute of Ultrasound in Medicine J Ultrasound Med 18: , /99/$3.50

2 640 URETERL TUMORS J Ultrasound Med 18: , 1999 levels of the ureter; this modality was capable of demonstrating both the length and the extent of the tumor. SUJECTS ND METHODS During the years 1989 to 1998, 16 patients (five women, 11 men; 56 to 92 years old) were diagnosed in our hospital as having ureteral tumors. ll of them underwent ultrasonographic examination. Eleven patients with no history of TCC had been referred, seven for hematuria evaluation, and four for flank pain investigation. Five patients were asymptomatic and were referred for routine follow-up ultrasonography for known past bladder TCC. During this period we performed follow-up examinations on 507 patients after bladder tumor resection. ll patients with bladder tumor are being followed by urine cytology and cystoscopy examinations every 3 months for the first 2 years, and by sonographic examination every 6 months. fterward they are examined annually. IVU is performed in cases of positive cytologic and negative ultrasonographic results. Of the 507 patients, 12 were lost to follow-up study. Of note is the fact that during this period an additional nine patients were diagnosed as suffering from renal TCC (calyceal or pelvic). ll of these patients were diagnosed by ultrasonography as well as by IVU and CT. The sonographic examination was performed transabdominally, after ingestion of water, using an TL Ultramark 9 (dvanced Technology Laboratories, othell, W) or an Elscint ESI 1000 (Hackensack, NJ) unit with 3.5 MHz, 5 MHz, and 7.5 MHz probes. ll sonographic examinations were conducted by an experienced senior radiologist (I.H.H.) and included meticulous monitoring of the ureter. Compression or position changes by the patient were used when the middle third of the ureter was obscured by bowel gas. In all cases the ureter could be demonstrated as far as the tumor level. s a result of the added manipulations the ultrasonographic examinations were longer than usual, lasting as much as 30 to 40 min. Ten patients underwent IVU; in four of them the examination was performed prior to ultrasonography and in six patients after ultrasonography. Three patients underwent retrograde pyelography, and 11 patients underwent CT scanning. ll CT examinations were performed after ultrasonography. In the 12 patients who subsequently had surgical removal of the affected kidney and ureter, the results of abdominal ultrasonography were compared to the pathologic findings. The other four patients did not have surgery because of advanced disease. Two of these patients had undergone needle biopsy of enlarged retroperitoneal lymph nodes. RESULTS The sonographic, IVU, CT, and retrograde pyelographic findings are summarized in Table 1. In all 16 cases transabdominal ultrasonography was diagnostic for ureteral tumor, demonstrating an intraluminal hypoechoic solid mass ranging in length from 4 mm to 7 cm (Fig. 1). In 11 patients, the tumor caused local expansion of the ureteral diameter, up to 4 cm in one case (Fig. 2). The degree of severity of hydronephrosis as shown by the sonographic examination included minimal (two patients), mild (five patients), moderate (eight patients), and severe (one patient). Three tumors were located in the upper third of the ureter, four were in the middle third, and nine were in the distal third. In two patients adjacent lymphadenopathy was noted. mong the four patients who underwent IVU prior to ultrasonography, one had a nonfunctioning kidney, two had unexplained hydronephrosis, and one had a filling defect in the ureter. In the six patients who had IVU after the sonographic diagnosis, three had a nonfunctioning kidney, two had a filling defect, and one had unexplained ureterohydronephrosis. Of the three patients with filling defects on the IVU, two ureters had irregular contours, whereas one showed smooth contours and hence could have represented either a tumor or a stone. On retrograde pyelography, two patients exhibited a filling defect, and one patient demonstrated truncation of the ureter. mong the 11 patients who were studied by CT, tumors were clearly identified in seven; in two patients, the tumor was not optimally demonstrated and was identified only retrospectively, and in two additional patients, the CT results proved to be false negative. Excellent correlation was found between ultrasonographic diagnosis and pathologic findings, with no false-positive results. DISCUSSION TCC of the ureter accounts for 2.5 to 5% of TCC involving the urinary tract. 6 Patients usually have hematuria or flank pain as the presenting feature.

3 J Ultrasound Med 18: , 1999 HDS-HLPERN ET L 641 Discovering TCC of the ureter incidentally on routine follow-up examination of patients with known bladder TCC is considered to be rare. 2 IVU generally is considered the primary diagnostic tool, and it may be used in identification of the following conditions: nonfunctioning kidney (in 46% of Table 1: Summary of Characteristics in Patients with Ureteral Tumors Patient No./ Year of Initial US IVU CT RP ge (yr)/sex Diagnosis Symptoms Findings Findings Findings Findings 1/76/M 1989 Hematuria Mass in midureter, Nonfunctioning Filling defect 7 cm long; mild kidney; solid mass in midureter in ureter 2/81/M 1989 Follow-up T Mass in proximal ureter, Papillary filling Solid mass in 2.5 cm long; moderate defect in proximal ureter proximal ureter 3/78/F 1990 Hematuria Mass in proximal ureter, Nonfunctioning Solid mass in Cutoff of 1.0 cm long; moderate kidney proximal ureter upper ureter 4/86/M 1990 Follow-up T Mass in distal ureter, Mild ; tumor 1 cm long; mild not demonstrated 5/79/M 1992 Flank pain Mass in distal ureter, Nondiagnostic 3 cm long; mild 6/77/M 1992 Flank pain Mass in proximal ureter, Filling defect in Solid mass in 1.5 cm long; mild upper ureter upper ureter 7/64/M* 1993 Flank pain Mass in midureter, Minimal ; Filling defect 1.3 cm long; minimal undetermined in midureter filling defect 8/66/M 1993 Hematuria Mass in distal ureter, Nonfunctioning Moderate; 4 cm long; moderate kidney mass seen retrospectively 9/91/F 1993 Hematuria Mass in distal ureter, Mass in distal 0.4 cm long; moderate ureter 10/82/F 1993 Hematuria Mass in distal ureter, Moderate ; 4 cm long; moderate mass in distal ; RLN ureter; RLN 11/58/M* 1994 Hematuria Mass in midureter, Moderate ; Moderate ; 2.5 cm long; moderate undetermined mass seen filling defect retrospectively 12/56/M 1995 Hematuria Mass in distal ureter, Nonfunctioning Mass in distal 3.5 cm long; mild kidney ureter 13/68/F 1996 Follow-up T Mass in distal ureter,, tumor not 1.5 cm long; moderate demonstrated 14/80/F 1996 Follow-up T Mass in distal ureter, 0.4 cm long; moderate ; RLN 15/92/M* 1996 Follow-up T Mass in midureter, Filling defect 1.4 cm long; minimal in midureter 16/57/M* 1998 Flank pain Mass in distal ureter, Nonfunctioning 3.5 cm long; severe kidney *IVU performed prior to ultrasonography. US, Ultrasonography; RP, Retrograde pyelography; T, ladder tumor; RLN, retroperitoneal lymphadenopathy;, Ureterohydronephrosis.

4 642 URETERL TUMORS J Ultrasound Med 18: , 1999 Figure 1 Transabdominal ultrasonogram in an 80 year old woman undergoing follow-up ultrasonography for past bladder tumor reveals a small 4 mm long soft tissue mass in the left distal ureter (arrow). The patient did not undergo surgery owing to presence of metastatic retroperitoneal lymph nodes. Figure 2 Transabdominal ultrasonogram in an 82 year old woman who had had macrohematuria for 2 years shows a soft tissue mass projecting into and expanding the lumen in the distal third of the ureter (arrow). cases), hydronephrosis with or without hydroureter (in 34% of cases), ureteral filling defect (in 19% of cases), and fixation of the ureter with irregular narrowing (circumferential or eccentric) of the lumen. 2 Thus, IVU is an imperfect tool for diagnosis in cases of nonfunctioning kidney (Fig. 3). In cases in which a filling defect is demonstrated, it is not always possible to differentiate tumor from stone, especially when the defect has smooth margins. In addition, IVU necessitates use of injected contrast medium and exposure to radiation. Retrograde pyelography is an invasive technique and cannot always be accomplished. 7 ntegrade pyelography is invasive as well, and it carries the risk of tumor seeding. 2 We did not use this technique as it was unnecessary in our patients. s it is noninvasive, does not require injection of contrast agent, and is not restricted by kidney function, some radiologists initiate evaluation of the urinary tract with ultrasonographic examination of the kidneys and bladder; however, sonography is considered to be of limited value in demonstrating pathologic conditions of the ureter. 2 ll patients described herein had some degree of ureterohydronephrosis and hence we were able to follow the ureter ultrasonographically to the level of the tumor and to demonstrate the exact nature of the obstructing lesion. The intraluminal soft tissue mass was clearly depicted, as it failed to produce acoustic shadowing, as opposed to the shadowing caused by calculi. The soft tissue mass in cases of tumor usually causes local expansion of the ureteral diameter, which may reach a considerable extent before penetrating the wall (Fig. 4). Technical problems might occur on assessing the ureter when the tumor is in the middle third, an area often obscured by bowel gas; we were able to overcome this problem by compressing the area to be examined and changing the patient s position. Of note is the fact that, although the incidental finding of TCC of the ureter during routine follow-up examination of known cases of bladder TCC is considered rare, we diagnosed it in five such patients who were still asymptomatic. lthough our patient group was small, we find that ultrasonography appears to be preferable over IVU as a diagnostic tool for TCC of the ureter. When retrograde pyelography was performed, no additional information was obtained (Fig. 5). The filling defect in the latter examination, as in the IVU, is not necessarily diagnostic and hence, the diagnostician might still need to differentiate between tumor and calculus. lso of importance is that these latter techniques (retrograde pyelography and IVU) are not always accurate in demonstrating the length of the filling defect, as the operator may obtain the proximal end on IVU or the distal end on retrograde pyelography. It has been reported that CT provides accurate information in approximately 90% of cases of ureteral TCC and is helpful in confirming the existence of subtle lesions when conventional studies are not definitive (e.g., differentiating nonradiopaque stones from tumor). 8,9 In our patients, the sonography results were accurate in

5 J Ultrasound Med 18: , 1999 HDS-HLPERN ET L 643 Figure 4 In a 56 year old man with macrohematuria, IVU revealed a nonfunctioning right kidney. Ultrasonography was requested., Longitudinal scan along the distal third of the ureter. soft tissue mass fills the ureteral lumen and expands it (asterisk)., ladder., The corresponding gross specimen demonstrates the tumor in a longitudinal section (arrow). C Figure 3 Patient was a 57 year old man with recurrent renal stones referred for left flank pain., IVU reveals nonfunctioning left kidney with a stone in the lower calyx., Ultrasonography shows ureterohydronephrosis. C, soft tissue mass is evident in the distal ureter (arrow).

6 644 URETERL TUMORS J Ultrasound Med 18: , 1999 all cases in depicting the lesions and describing their nature (Fig. 6), whereas the CT was inconclusive or gave false-negative results in four cases (Fig. 7). In conclusion, in our small patient group ultrasonography was superior to all other imaging modalities, with no false-positive findings and, to the best of our knowledge, no false-negative cases. In our institution, ultrasonography is an important complementary examination in patients with suspected TCC of the ureter. REFERENCES 1. Holm HH, Torp-Pedersen S, Larsen T, et al: Transabdominal and endoluminal ultrasonic scanning of the lower ureter. Scand J Urol Nephrol 157(Suppl):19, Wong-You-Cheong JJ, Wagner J, Davis CJ: Transitional cell carcinoma of the urinary tract: Radiologic-pathologic correlation. RadioGraphics 18:123, Lowe PP, Roylance J: Transitional cell carcinoma of the kidney. Clin Radiol 27:503, rennan RE, Pollack HM: Nonvisualized ( phantom ) renal calyx: Causes and radiological approach to diagnosis. Urol Radiol 1:17, atata M, Whitmore WF, Hilaris S, et al: Primary carcinoma of the ureter: prognostic study. Cancer 35:1626, Rachandani P, Pollack H: Tumors of the urothelium. Semin Roentgenol 30:149, 1995 Figure 5 Patient was a 64 year old man with right flank pain., IVU shows a filling defect of the middle third of the ureter suggestive of tumor (arrow)., Ultrasonogram shows clearly the small tumor filling the lumen (arrow). C, Retrograde pyelogram demonstrates the filling defect caused by the tumor. C

7 J Ultrasound Med 18: , 1999 HDS-HLPERN ET L 645 Figure 6 Patient was a 66 year old man with macrohematuria., IVU shows no excretion from the right kidney., Ultrasonogram shows soft tissue mass in the distal third of the right ureter (arrow). C, CT scan shows the distal right ureter to be dilated with dense material inside, which was seen retrospectively (arrow). 7. Kenney PJ, Stanley R: Computed tomography of ureteral tumors. J Comput ssist Tomogr 11:102, adalament R, ennett W, ova JG, et al: Computed tomography of primary transitional cell carcinoma of upper urinary tracts. Uroradiology 40:71, aron RL, McClennan L, Lee JKT, et al: Computed tomography of transitional cell carcinoma of the renal pelvis and ureter. Radiology 144:125, 1982 Figure 7 Patient was a 79 year old man with right flank pain., Ultrasonogram shows a tumor mass in the distal right ureter (arrows)., CT shows dilated right ureter with no obvious mass (arrow). C