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Preoperative Endoscopic Diagnosis of Fibroepithelial Polyp of the Renal Pelvis: A Case Report and Review of the Literature
0022-5347 /91/1453-0549$0:l.OO/G Vol. 145j 54S-551, IViarch 1991
THE JOURNAL OF UROLOGY
Printed in U.S.A.
Copyright© 1991 by AMERICAN UROLOGICAL ASSOCIATiON,
PREOPERATIVE ENDOSCOPIC DIAGNOSIS OF FIBROEPITHELIAL POLYP OF THE RENAL PELVIS: A CASE REPORT AND REVIEW OF THE LITERATURE MICHAEL T. MACFARLANE, AVI STEIN, LESTER LAYFIELD
AND
JEAN B. DEKERNION
From the Division of Urology and Department of Pathology, UCLA School of Medicine, Los Angeles, California
ABSTRACT
Benign fibroepithelial polyps of the renal pelvis are rare, with only 9 cases described previously in the literature. We report an additional case and suggest how nephrectomy may be avoided. KEY WORDS: polyps, epithelium, kidney pelvis
Tumors of the renal pelvis are most commonly malignant transitional cell carcinomas and the standard treatment is nephroureterectomy. Although rare, benign tumors of the renal pelvis do occur and they usually are of mesenchymal cell origin. Mistaking these masses for a malignant tumor would result in an unnecessary nephrectomy. We report a case in which modern preoperative diagnostic methods were used to avoid such an outcome. CASE REPORT
A 47-year-old man from Iran initially presented complaining of left testicular discomfort. Medical history was negative and physical examination was unremarkable. Routine urinalysis revealed microscopic hematuria. An excretory urogram (IVP) demonstrated a large filling defect of the right renal pelvis with normal fupctioning kidneys bilaterally (fig. 1). Abdominal com-
pelvis. Attempts to pass a flexible ureteroscope were unsuccessful. Rigid ureteroscopy up to the renal pelvis using a lOF ureteroscope revealed a normal ureter and a smooth surfaced mass occupying most of the renal pelvis. A point of attachment could not be appreciated. Using the 3F cold cup forceps 20 biopsies demonstrated normal transitional cell epithelium. A Double-J* ureteral stent was left in place because of the prolonged and difficult ureteroscopy. Open exploration of the right renal pelvis 1 week later revealed a large polyp in the renal pelvis attached to the upper calix. The polyp was easily removed with no evidence of residual tumor left in situ. Pathological studies confirmed a benign fibroepithelial polyp. Convalescence was uneventful. Pathological Findings: Gross examination of the specimen demonstrated a pale tan to gray white, 2.2 X 1.8 x 2.3 cm., soft fleshy polyp. The surface was covered by a slightly granular epithelium except at the base, which showed an edematous focally hemorrhagic glistening pale tan surface. Cross sections revealed an edematous to myxoid surface with foci of hemorrhage. Microscopic examination demonstrated a centrally edematous to myxoid fibrovascular stroma covered by a focally ulcerated and folded transitional cell epithelium (fig. 3). No significant atypia or epithelial thickening was present and cytological maturation appeared normal. The central stroma was composed of fine wavy collagen fibrils separated by edema with scattered short spindle-shaped to stellate cells containing small dark bland nuclei (fig. 4). A small number of smooth *Medical Engineering Corp., New York, New York.
FIG. 1. IVP demonstrates filling defect in right renal pelvis
puterized tomography (CT) with and without contrast medium confirmed the presence of a soft tissue mass in the right renal pelvis (fig. 2). Nephroureterectomy was recommended by the local urologist and the patient sought a second opinion. Review of the previous films confirmed the presence of a tumor in the right renal pelvis. Cystoscopy was normal. Washings from the bladder and right renal pelvis were cytologically negative for malignancy. A right retrograde pyelogram again confirmed the presence of the filling defect within the renal FIG. 2. Abdominal CT scan with intravenous contrast medium demonstrates right renal pelvic filling defect.
Accepted for publication August 24, 1990. 549
550
MACFARLANE AND ASSOCIATES
Fm. 3. Cross section of polyp shows focally ulcerated transitional epithelium surrounding myxoid and fibrovascular stromal core. H & E, reduced from X2.
Fm. 4. Fibromyxoid core with thin collagen bundles and bland spindle-shaped stromal cells containing small dark nuclei. H & E, reduced from X320.
muscle bundles were scattered throughout this background. Small arteries and dilated veins were distributed randomly within the fibromyxoid stroma. Mitotic activity was not detected within the stromal or epithelial components of the polyp. Foci of red blood cells were in the stroma.
renal pelvis are exceedingly rare with only 9 cases reported previously in the literature (see table). 1- 9 Benign ureteral tumors have been reported more frequently. 10 Benign tumors of the renal pelvis are classified by Williams and Niederhaeusern as follows: tumors of epithelial origin-papillomas (low grade transitional cell carcinoma); tumors of mesodermal originfibrous polyps, angiomatous polyps, hemangiomas or lymph-
DISCUSSION
Tumors of the renal pelvis are uncommon and most are malignant transitional cell carcinomas. Benign tumors of the
Benign fibroepithelial tumors of the renal pelvis: review of published cases Reference* Immergut and Cottier
Sex-Age F-32
Presenting Symptoms
Imaging Findings
Preop. Diagnosis
IVP, retrograde pyelogram; hydronephrosis with pelvic filling defect IVP, retrograde pyelogram; calicectasis, filling defect IVP, retrograde pyelogram; nonfunctioning kidney with filling defect IVP, retrograde pyelogram; filling defect
Papillary tumor ofrenal pelvis
Nephrectomy
No smooth muscle
Renal pelvic and ureteral lesions
Nephroureterectomy
Edema
Renal tumor
Partial resection of renal pelvis
Edema and smooth muscle
Tumor of renal pelvis
Polypectomy
Tumor of renal pelvis
Nephroureterectomy Nephroureterectomy Nephroureterectomy Polypectomy
Edema with myxomatous elements Lymphocytic infiltration
Medical History
Rt. flank pain, hematuria, frequency, urgency
Hematuria
Evans and Stevens•
M-4
Albuminuria, flank tenderness
Mother; toxemia of pregnancy
Shucksmith4
M-60
Hematuria, loin discomfort
Colon Ca, suprapubic hemicolectomy
Bernier et al6
F-42
Painless hematuria
Neg.
Toppercer6
F-40
Cystitis, microhematuria Flank pain
Neg.
Edelman et aF
M-17
Blank et al8
F-37
Flank pain, fever, chills
Neg.
Thomsen and Egebo9
M-77
Flank pain, fever, chills
Prostate Ca, diethylstilbestrol
Present case
M-47
Lt. testicular pain, micro~ hematuria
Neg.
Neg.
IVP, retrograde pyelogram; filling defect IVP, retrograde pyelogram; filling defect IVP, retrograde pyelogram; filling defect IVP, retrograde pyelogram; filling defect, nonfunctioning kidney IVP, retrograde pyelogram, CT, ureteroscopy, biopsy; filling defect, soft tissue mass
* Boross reported a case but none of the characteristics identified was available!
Stone Stone Tumor of renal pelvis
Tumor of renal pelvis (biopsy and cytology-normal epithelium)
Treatment
Polypectomy
Histological Characteristics
Cysts, dilatation of lymphatics
Edema and smooth muscle
551
Fi:BROEPITHELIAL POLYP OF RENAL PELVIS
angiomas, leiomyomas and neurofibromas, and miscellaneous types-endometriosis, amyloidosis and granulomas. 11 The origin of these lesions is unknown. Suggested etiologies include congenital, irritation, infection or hormonal imbalances. The most frequent site of occurrence for benign polyps of the upper tracts is the proximal ureter (more than 100 patients reported between 5 and 40 years old) but they may be more frequent because even small tumors can present with obstruction. Renal pelvic tumors tend to occur in an older age group. The most common presenting signs and symptoms are hematuria, flank pain, cystitis, fever and chills. Our patient complained of vague discomfort in the contralateral testis, which prompted routine urinalysis demonstrating hematuria. IVPs will usually demonstrate a filling defect within the pelvis. Urine cytology will show normal cells in these cases because of the normal overlying epithelium. Ultrasonography and CT should be able to differentiate a stone. Ureteroscopy will allow direct visualization of the lesion and biopsy for histological identification. The smooth appearance of the lesion and multiple biopsies demonstrating only normal transitional cell epithelium convinced us to explore the renal pelvis in our case. The concept of not opening the ureter or the renal pelvis, causing cancer cell spillage, is considered the standard of care for upper tract tumors. A renal sparing approach in the presence of a normal contralateral system has not been our practice. However, in the setting of normal cytological washings and multiple negative histological biopsies with a benign-appearing lesion, this approach may prevent an unnecessary nephrectomy as occurred in at least 5 of the 9 previously reported cases. Preoperative confirmation of malignancy should be made when
possible before embarking on radical surgery. Endoscopic ma,: agement of renal pelvic tumors in selected cases has been suggested12 and may have a role in treating such tumors.
REFERENCES 1. Boross, E.: Fibroma of renal pelvis. Orvosi hetil., 73: 1055, 1929.
2. Immergut, S. and Cottier, Z. R.: Intrapelvic fibroma. J. Urol., 66: 673, 1951. 3. Evans, A. T. and Stevens, R. K.: Fibroepithelial polyps of ureter and renal pelvis: a case report. J. Urol., 86: 313, 1961. 4. Shucksmith, H. S.: Fibroma of the renal pelvis. Brit. J. Urol., 35: 261, 1963. 5. Bernier, L., Bedard, A. and Narcisse, R.: Fibrome du bassinet. Canad. J. Surg., 13: 315, 1970. 6. Toppercer, A.: Fibroepithelial tumour of the renal pelvis. Canad. J. Surg., 23: 269, 1980. 7. Edelman, R., Kim, E. S. and Bard, R. H.: Benign fibroepithelial polyp of the renal pelvis. Brit. J. Urol., 54: 321, 1982. 8. Blank, C., Lissmer, L., Kaneti, J., Glikman, L., Moroko, I. and Krugliak, L.: Fibroepithelial polyp of the renal pelvis. J. Urol., 137: 962, 1987. 9. Thomsen, H. and Egebo, K.: Solitary fibroepithelial polyp of the renal pelvis. Urol. Int., 42: 456, 1987. 10. Debruyne, F. M. J., Moonen, W. A., Daenekindt, A. A. and Delaere, K. P. J.: Fibroepithelial polyp of ureter. Urology, 16: 355, 1980. 11. Williams, D. I. and Niederhaeusern, W. von: Polyps of the ureter. J. Ural. Nephrol., 69: 145, 1963. 12. Blute, M. L., Segura, J. W., Patterson, D. E., Benson, R. C., Jr. and Zincke, H.: Impact of endourology on diagnosis and management of upper urinary tract urothelial cancer. J. Urol., 141: 1298, 1989.
THE JOURNAL OF UROLOGY
Printed in U.S.A.
Copyright© 1991 by AMERICAN UROLOGICAL ASSOCIATiON,
PREOPERATIVE ENDOSCOPIC DIAGNOSIS OF FIBROEPITHELIAL POLYP OF THE RENAL PELVIS: A CASE REPORT AND REVIEW OF THE LITERATURE MICHAEL T. MACFARLANE, AVI STEIN, LESTER LAYFIELD
AND
JEAN B. DEKERNION
From the Division of Urology and Department of Pathology, UCLA School of Medicine, Los Angeles, California
ABSTRACT
Benign fibroepithelial polyps of the renal pelvis are rare, with only 9 cases described previously in the literature. We report an additional case and suggest how nephrectomy may be avoided. KEY WORDS: polyps, epithelium, kidney pelvis
Tumors of the renal pelvis are most commonly malignant transitional cell carcinomas and the standard treatment is nephroureterectomy. Although rare, benign tumors of the renal pelvis do occur and they usually are of mesenchymal cell origin. Mistaking these masses for a malignant tumor would result in an unnecessary nephrectomy. We report a case in which modern preoperative diagnostic methods were used to avoid such an outcome. CASE REPORT
A 47-year-old man from Iran initially presented complaining of left testicular discomfort. Medical history was negative and physical examination was unremarkable. Routine urinalysis revealed microscopic hematuria. An excretory urogram (IVP) demonstrated a large filling defect of the right renal pelvis with normal fupctioning kidneys bilaterally (fig. 1). Abdominal com-
pelvis. Attempts to pass a flexible ureteroscope were unsuccessful. Rigid ureteroscopy up to the renal pelvis using a lOF ureteroscope revealed a normal ureter and a smooth surfaced mass occupying most of the renal pelvis. A point of attachment could not be appreciated. Using the 3F cold cup forceps 20 biopsies demonstrated normal transitional cell epithelium. A Double-J* ureteral stent was left in place because of the prolonged and difficult ureteroscopy. Open exploration of the right renal pelvis 1 week later revealed a large polyp in the renal pelvis attached to the upper calix. The polyp was easily removed with no evidence of residual tumor left in situ. Pathological studies confirmed a benign fibroepithelial polyp. Convalescence was uneventful. Pathological Findings: Gross examination of the specimen demonstrated a pale tan to gray white, 2.2 X 1.8 x 2.3 cm., soft fleshy polyp. The surface was covered by a slightly granular epithelium except at the base, which showed an edematous focally hemorrhagic glistening pale tan surface. Cross sections revealed an edematous to myxoid surface with foci of hemorrhage. Microscopic examination demonstrated a centrally edematous to myxoid fibrovascular stroma covered by a focally ulcerated and folded transitional cell epithelium (fig. 3). No significant atypia or epithelial thickening was present and cytological maturation appeared normal. The central stroma was composed of fine wavy collagen fibrils separated by edema with scattered short spindle-shaped to stellate cells containing small dark bland nuclei (fig. 4). A small number of smooth *Medical Engineering Corp., New York, New York.
FIG. 1. IVP demonstrates filling defect in right renal pelvis
puterized tomography (CT) with and without contrast medium confirmed the presence of a soft tissue mass in the right renal pelvis (fig. 2). Nephroureterectomy was recommended by the local urologist and the patient sought a second opinion. Review of the previous films confirmed the presence of a tumor in the right renal pelvis. Cystoscopy was normal. Washings from the bladder and right renal pelvis were cytologically negative for malignancy. A right retrograde pyelogram again confirmed the presence of the filling defect within the renal FIG. 2. Abdominal CT scan with intravenous contrast medium demonstrates right renal pelvic filling defect.
Accepted for publication August 24, 1990. 549
550
MACFARLANE AND ASSOCIATES
Fm. 3. Cross section of polyp shows focally ulcerated transitional epithelium surrounding myxoid and fibrovascular stromal core. H & E, reduced from X2.
Fm. 4. Fibromyxoid core with thin collagen bundles and bland spindle-shaped stromal cells containing small dark nuclei. H & E, reduced from X320.
muscle bundles were scattered throughout this background. Small arteries and dilated veins were distributed randomly within the fibromyxoid stroma. Mitotic activity was not detected within the stromal or epithelial components of the polyp. Foci of red blood cells were in the stroma.
renal pelvis are exceedingly rare with only 9 cases reported previously in the literature (see table). 1- 9 Benign ureteral tumors have been reported more frequently. 10 Benign tumors of the renal pelvis are classified by Williams and Niederhaeusern as follows: tumors of epithelial origin-papillomas (low grade transitional cell carcinoma); tumors of mesodermal originfibrous polyps, angiomatous polyps, hemangiomas or lymph-
DISCUSSION
Tumors of the renal pelvis are uncommon and most are malignant transitional cell carcinomas. Benign tumors of the
Benign fibroepithelial tumors of the renal pelvis: review of published cases Reference* Immergut and Cottier
Sex-Age F-32
Presenting Symptoms
Imaging Findings
Preop. Diagnosis
IVP, retrograde pyelogram; hydronephrosis with pelvic filling defect IVP, retrograde pyelogram; calicectasis, filling defect IVP, retrograde pyelogram; nonfunctioning kidney with filling defect IVP, retrograde pyelogram; filling defect
Papillary tumor ofrenal pelvis
Nephrectomy
No smooth muscle
Renal pelvic and ureteral lesions
Nephroureterectomy
Edema
Renal tumor
Partial resection of renal pelvis
Edema and smooth muscle
Tumor of renal pelvis
Polypectomy
Tumor of renal pelvis
Nephroureterectomy Nephroureterectomy Nephroureterectomy Polypectomy
Edema with myxomatous elements Lymphocytic infiltration
Medical History
Rt. flank pain, hematuria, frequency, urgency
Hematuria
Evans and Stevens•
M-4
Albuminuria, flank tenderness
Mother; toxemia of pregnancy
Shucksmith4
M-60
Hematuria, loin discomfort
Colon Ca, suprapubic hemicolectomy
Bernier et al6
F-42
Painless hematuria
Neg.
Toppercer6
F-40
Cystitis, microhematuria Flank pain
Neg.
Edelman et aF
M-17
Blank et al8
F-37
Flank pain, fever, chills
Neg.
Thomsen and Egebo9
M-77
Flank pain, fever, chills
Prostate Ca, diethylstilbestrol
Present case
M-47
Lt. testicular pain, micro~ hematuria
Neg.
Neg.
IVP, retrograde pyelogram; filling defect IVP, retrograde pyelogram; filling defect IVP, retrograde pyelogram; filling defect IVP, retrograde pyelogram; filling defect, nonfunctioning kidney IVP, retrograde pyelogram, CT, ureteroscopy, biopsy; filling defect, soft tissue mass
* Boross reported a case but none of the characteristics identified was available!
Stone Stone Tumor of renal pelvis
Tumor of renal pelvis (biopsy and cytology-normal epithelium)
Treatment
Polypectomy
Histological Characteristics
Cysts, dilatation of lymphatics
Edema and smooth muscle
551
Fi:BROEPITHELIAL POLYP OF RENAL PELVIS
angiomas, leiomyomas and neurofibromas, and miscellaneous types-endometriosis, amyloidosis and granulomas. 11 The origin of these lesions is unknown. Suggested etiologies include congenital, irritation, infection or hormonal imbalances. The most frequent site of occurrence for benign polyps of the upper tracts is the proximal ureter (more than 100 patients reported between 5 and 40 years old) but they may be more frequent because even small tumors can present with obstruction. Renal pelvic tumors tend to occur in an older age group. The most common presenting signs and symptoms are hematuria, flank pain, cystitis, fever and chills. Our patient complained of vague discomfort in the contralateral testis, which prompted routine urinalysis demonstrating hematuria. IVPs will usually demonstrate a filling defect within the pelvis. Urine cytology will show normal cells in these cases because of the normal overlying epithelium. Ultrasonography and CT should be able to differentiate a stone. Ureteroscopy will allow direct visualization of the lesion and biopsy for histological identification. The smooth appearance of the lesion and multiple biopsies demonstrating only normal transitional cell epithelium convinced us to explore the renal pelvis in our case. The concept of not opening the ureter or the renal pelvis, causing cancer cell spillage, is considered the standard of care for upper tract tumors. A renal sparing approach in the presence of a normal contralateral system has not been our practice. However, in the setting of normal cytological washings and multiple negative histological biopsies with a benign-appearing lesion, this approach may prevent an unnecessary nephrectomy as occurred in at least 5 of the 9 previously reported cases. Preoperative confirmation of malignancy should be made when
possible before embarking on radical surgery. Endoscopic ma,: agement of renal pelvic tumors in selected cases has been suggested12 and may have a role in treating such tumors.
REFERENCES 1. Boross, E.: Fibroma of renal pelvis. Orvosi hetil., 73: 1055, 1929.
2. Immergut, S. and Cottier, Z. R.: Intrapelvic fibroma. J. Urol., 66: 673, 1951. 3. Evans, A. T. and Stevens, R. K.: Fibroepithelial polyps of ureter and renal pelvis: a case report. J. Urol., 86: 313, 1961. 4. Shucksmith, H. S.: Fibroma of the renal pelvis. Brit. J. Urol., 35: 261, 1963. 5. Bernier, L., Bedard, A. and Narcisse, R.: Fibrome du bassinet. Canad. J. Surg., 13: 315, 1970. 6. Toppercer, A.: Fibroepithelial tumour of the renal pelvis. Canad. J. Surg., 23: 269, 1980. 7. Edelman, R., Kim, E. S. and Bard, R. H.: Benign fibroepithelial polyp of the renal pelvis. Brit. J. Urol., 54: 321, 1982. 8. Blank, C., Lissmer, L., Kaneti, J., Glikman, L., Moroko, I. and Krugliak, L.: Fibroepithelial polyp of the renal pelvis. J. Urol., 137: 962, 1987. 9. Thomsen, H. and Egebo, K.: Solitary fibroepithelial polyp of the renal pelvis. Urol. Int., 42: 456, 1987. 10. Debruyne, F. M. J., Moonen, W. A., Daenekindt, A. A. and Delaere, K. P. J.: Fibroepithelial polyp of ureter. Urology, 16: 355, 1980. 11. Williams, D. I. and Niederhaeusern, W. von: Polyps of the ureter. J. Ural. Nephrol., 69: 145, 1963. 12. Blute, M. L., Segura, J. W., Patterson, D. E., Benson, R. C., Jr. and Zincke, H.: Impact of endourology on diagnosis and management of upper urinary tract urothelial cancer. J. Urol., 141: 1298, 1989.