TY - JOUR
T1 - Neurofibroma of the urinary bladder
AU - Cheng, Liang
AU - Scheithauer, Bernd W.
AU - Leibovich, Bradley C.
AU - Ramnani, Dharamdas M.
AU - Cheville, John C.
AU - Bostwick, David G.
PY - 1999/8/1
Y1 - 1999/8/1
N2 - BACKGROUND. Neurofibroma of the urinary bladder is rare. Only isolated case reports have appeared. Information regarding the long term follow-up of patients with neurofibroma is limited. METHODS. The authors studied 4 cases of neurofibroma of the bladder diagnosed at Mayo Clinic from 1965 through 1990. Immunostains for S-100 protein, neurofilament protein, epithelial membrane antigen (EMA), cytokeratin (CAM 5.2; AE 1/3), Type IV collagen, MIB- 1, and p53 protein were performed in all cases, as was Alcian blue at pH 2.5. The mean follow-up was 9.6 years (range, 2-18 years). RESULTS. The mean age at diagnosis was 17 years (range, 7-28 years); the male-to-female ratio was 1:1. All four patients exhibited physical stigmata of neurofibromatosis type 1. Clinical presentations included hematuria (one patient), irritative symptoms (two patients), and pelvic mass (one patient). Long term urinary complications included bladder atony (two patients), neurogenic bladder (one patient), and recurrent urinary tract infection with hematuria (one patient). Subsequently, two patients underwent partial cystectomy and one a complete cystectomy. Involvement of the bladder was generalized in all four cases. Three tumors were transmural, showing a diffuse and plexiform pattern of growth; in the fourth case, a superficial biopsy showed only diffuse submucosal growth with conspicuous pseudo-Meissnerian corpuscle formation. An Alcian blue positive, variably collagenized matrix was present in all cases. Tumor cells displayed immunoreactivity for S-100 protein and Type IV collagen in all cases. Neurofilament protein positive axons were evident in three cases; all other immunostains were negative. The mean MIB-1 labeling index was 3.2% (range, 0.9-7.3%). No malignant transformation was observed during a mean follow-up of 9.6 years. CONCLUSIONS. Neurofibroma of the bladder presents early in life, is of the plexiform type with a diffuse component, and usually occurs in the setting of generalized neurofibromatosis type 1 rather than as isolated visceral neurofibromatosis. Malignant transformation did not occur in any of these 4 patients during a mean follow-up time of 9.6 years.
AB - BACKGROUND. Neurofibroma of the urinary bladder is rare. Only isolated case reports have appeared. Information regarding the long term follow-up of patients with neurofibroma is limited. METHODS. The authors studied 4 cases of neurofibroma of the bladder diagnosed at Mayo Clinic from 1965 through 1990. Immunostains for S-100 protein, neurofilament protein, epithelial membrane antigen (EMA), cytokeratin (CAM 5.2; AE 1/3), Type IV collagen, MIB- 1, and p53 protein were performed in all cases, as was Alcian blue at pH 2.5. The mean follow-up was 9.6 years (range, 2-18 years). RESULTS. The mean age at diagnosis was 17 years (range, 7-28 years); the male-to-female ratio was 1:1. All four patients exhibited physical stigmata of neurofibromatosis type 1. Clinical presentations included hematuria (one patient), irritative symptoms (two patients), and pelvic mass (one patient). Long term urinary complications included bladder atony (two patients), neurogenic bladder (one patient), and recurrent urinary tract infection with hematuria (one patient). Subsequently, two patients underwent partial cystectomy and one a complete cystectomy. Involvement of the bladder was generalized in all four cases. Three tumors were transmural, showing a diffuse and plexiform pattern of growth; in the fourth case, a superficial biopsy showed only diffuse submucosal growth with conspicuous pseudo-Meissnerian corpuscle formation. An Alcian blue positive, variably collagenized matrix was present in all cases. Tumor cells displayed immunoreactivity for S-100 protein and Type IV collagen in all cases. Neurofilament protein positive axons were evident in three cases; all other immunostains were negative. The mean MIB-1 labeling index was 3.2% (range, 0.9-7.3%). No malignant transformation was observed during a mean follow-up of 9.6 years. CONCLUSIONS. Neurofibroma of the bladder presents early in life, is of the plexiform type with a diffuse component, and usually occurs in the setting of generalized neurofibromatosis type 1 rather than as isolated visceral neurofibromatosis. Malignant transformation did not occur in any of these 4 patients during a mean follow-up time of 9.6 years.
KW - Bladder
KW - Immunohistochemistry
KW - Malignant malformation
KW - Neoplasms
KW - Neurofibroma
KW - Neurofibromatosis type 1
KW - Soft tissue
KW - Tumor
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U2 - 10.1002/(SICI)1097-0142(19990801)86:3<505::AID-CNCR20>3.0.CO;2-A
DO - 10.1002/(SICI)1097-0142(19990801)86:3<505::AID-CNCR20>3.0.CO;2-A
M3 - Article
C2 - 10430260
AN - SCOPUS:0033178797
SN - 0008-543X
VL - 86
SP - 505
EP - 513
JO - Cancer
JF - Cancer
IS - 3
ER -