PL 27. The clinical character of pelvic lipomatosis (PL)

Pelvic lipomatosis (PL) is proliferative disease characteristic with overgrowth of normal fat in the perivesical or perirectal space. Since it was initially described by Fogg and Smyth in 1968, not more than 150 cases in the English literatures and about 70 cases in native journals had been reported. Despite its low incidence and benign features, more than 50% of patients are symptomatic because of mass sensation, compressive neuropathy or associated chronic cystitis. Some patients will progressively develop obstructive hydronephrosis due to compression of excessive fat tissue, and 40% of the patients at a mean of 5 years after diagnosis of obstruction will progress into renal failure. It is reported that more than 75% of patients with PL as well suffered the diseases of cystitis glandularis, cystitis cystica, or cystitis follicularis. Moreover, it has been learned that proliferative diseases, especially adenomatous proliferation, are regarded as a potential precancerosis of adenocarcinoma.

We had some special urodynamic findings in the PL patients several years before. A total of 29 patients were diagnosed of pelvic lipomatosis by MRI and/or CT together with Barium radiography and IVU. Cystitis glandularis was found in 21 patients by biopsy. We divided all the patients into two groups, pelvic lipomatosis with cystitis glandularis and pure pelvic lipomatosis (without cystitis glandularis), 21 and 8, respectively. Twenty-six patients had BOO in the urodynamic study. We found distinct interesting pressure and flow curve in 13 patients. It showed that in the first half urination the detrusor pressure was not high with high urinary flow, but in the latter half urination the detrusor pressure became very high with very low urinary flow. We called "Latter Half Section Obstruction"(LHSO) to this kind of relationship between pressure and flow. There was 1 patient had LHSO in the group of pure pelvic lipomatosis, but 12 patients in the other group, (P=0.044).

In order to understand the relationship between the pelvic lipomatosis and glandular cystitis, we chose the cases who were ultimately diagnosed as cases of pelvic lipomatosis, then we retrospectively compared their clinical data with the other glandular cystitis patients, From 1990 to 2010, a total of 143 male patients were pathologically confirmed as " glandular cystitis " in the Department of Urology, Peking University First Hospital, among which 56 patients were finally diagnosed as pelvic lipomatosis. we compared their clinical data with the remaining 87 patients to improve the diagnosis and treatment level of pelvic lipomatosis in the male "glandular cystitis' patients. The incidence of "hypertension" and "high body mass index"(BMI>25) in both groups showed no significant difference; but patients with pelvic lipomatosis had an increased proportion of "dysuria" and "back pain" in symptoms (P = 0.022); Also the pelvic lipomatosis group had more cases with "hydronephrosis or hydroureter" and "bladder wall thickening" by ultrasound than the control group (P <0.001);in cystoscopy, the pelvic lipomatosis group were found to have a significantly higher proportion in "extension of the posterior urethra" and "bladder posterior lip elevation" (P <0.001); after the transurethral resection of bladder tumor treatment ,the pelvic lipomatosis group yields a higher alleviation rate on "the upper urinary tract water "and lower "glandular cystitis recurrence" rate. We also had some new findings in the analyzing radiological features of CT and MRI in the PL patients. Significant difference of bladder shape was found between PL (n=32) and normal control men (n=25) (P<0.05). The patients in PL showed a statistically significant increase in SI/AP, rLPU and RCI (P<0.05), as well as a remarkable decrease in AAP and bilateral BSA (P<0.05). All patients in PL presented with various degrees of cystipathy. 29 patients (58 ureters) showed various degrees of obtruction in unilateral or bilateral ureters (mild=22, moderate=23, severe=13). So we think that the shape of bladder is characteristics for diagnosis of pelvis lipomatosis. High incidence of ureter obstruction and glandular cystitis are demonstrated in patients of PL.