The Value of Isotope Nephrography in Carcinoma of Cervix: Follow up Studies of Pre and Post Irradiation

t is a great value to find an early detection of involvement of ureteric obstruction in the carcinoma of cervix. Little or or knowledge of the condition of the kidneys or the lower urinary tract are able to elucidate by the biochemical studies such as blood nitrogen or urine creatinine in carcinoma of cervix. Findings of urography delineates the condition of urinary tract stasis in the renal pelvis and ureters, however, slight stasis maybe difficult to demonstrate. On the other hand isotope nephrography is accepted as a sensitive method to observe renal function especially in regarding to the excretory function of kidney. It was attempted to analysis the findings of urography conjunction with isotope nephrography in 50 cases of unselected patients with invasive carcinoma of cervix through pre and post irradiation follow up studies. Urography was done as a routine procedure and analysed emphasising changes of collecting systems and ureter condition. Isotope nephrography was carried out by means of 15μci 131I Hippuran injected intravenously and the curves were analysed as follows. Parameter were; time of maximum amplitude (Tmax), half time of maximum amplitude (T1/2), Kac and Kex value calculated from these two parameters in Tobe's method. The excretion index by Aurell defines the ratio between the maximum activity and the activity measured on the slope of the third phase ten minutes after it has reached its maximum. Results:1) 28.8% had an abnormal IVP suggestive of ureteric involvement before irradiation therapy and the patient of stage III: and IV were the great part. 2) 21.7% had abnormal findings of per-irradiation renogram whom showed normal IVP. The other group showed normal IVP which group also showed normal renogram prior irradiation. 3) The more severe the ureteric involvement, the change of excretion index was greater. 4) Even in stage I and II patient, abnormal renogram was revealed in 12 cases (39.4%) among 31 cases. 5) All cases of TAH showed abnormal findings of IVP and renogram. 6) No definite change of renogram was obtained just after the irradiation therapy (point A:8000-9000 rads, B:5000-6000 rads, Co:11000-13000 rads). Each 3 month follow up study was performed and comparing with preirradiation study which showed significant changes of excretion index of renogram were 42.8% in 6-9 month follow-up and 75% in 9-12 month, respectively. 7) It seems to be important to observe the parameter Kex and excretion index of renogram to determine early abnormality of kidney excretory function by means of post-irradiation follow-up study.