Keywords: "Tcm-HSA, Lymphoscintigraphy, Lymphoedema, Uterine cancer, Radiation therapy. Abstract. To evaluate ... involving the regional lymphnodes and filarial infes- ..... radiocolloids in the parasternal lymphnodes of rabbits. Journal of ...
1991, The British Journal of Radiology, 64, 1119-1121
Quantitative lymphoscintigraphy using "Tc m human serum albumin in patients with previously treated uterine cancer By M. Kataoka, MD, PhD, M. Kawamura, MD, PhD, *K. Hamada, MD, PhD, H. Itoh, MD, PhD, Y. Nishiyama, MD and K. Hamamoto, MD, PhD Department of Radiology and 'Department of Obstetrics and Gynaecology, Ehime University, School of Medicine, Shitsukawa, Shigenobu-cho, Onsen-gun, Ehime 791-02, Japan {Received February 1991 and in revised form June 1991) Keywords: "Tc m -HSA, Lymphoscintigraphy, Lymphoedema, Uterine cancer, Radiation therapy
Abstract. To evaluate the clinical usefulness of lymphoscintigraphy using "Tc m human serum albumin ("Tc m -HSA) in assessing lymphoedema in the lower extremities, lymphoscintigraphy was performed by subcutaneous injection of 7.4 MBq of "Tc m -HSA in 26 patients with uterine cancer, previously treated by operation (OP) and/or radiation therapy (RT), and in five controls. Radioactivity at the injection site in the lower extremities was counted for 3 min at 10 min (A) and at 3 h (B) after injection, and clearance of "Tc m -HSA was defined as (1—(B)/(A))x 100(%). Clearance in controls was 46.8 + 3.9%, which was significantly more than those in the other treatment groups. Clearances in patients treated with both OP and RT were less than those in patients treated with either OP or RT alone (30.1 + 11.4 vs. 41.9 + 8.9, 43.7 ±9.6%, respectively; p < 0.01). The clearance in legs with lymphoedema was less than those without lymphoedema in patients treated with both OP and RT (16.6 + 7.7 vs. 34.9 + 9.3%; p < 0.01) and in patients treated with RT (33.1+7.4 vs. 48.0 + 5.6%; p < 0.01). There was a significant difference between clearance in controls and clearance in non-oedematous patients' legs treated with OP and RT (p < 0.01). In patients treated with RT alone, radiation dose was closely correlated with "Tc m -HSA clearance and with the development of lymphoedema. These data suggest that lymphoscintigraphy using "Tc m -HSA is useful in evaluating lymphoedema and that radiation dose is one of the factors in the development of lymphoedema.
Lymphoedema, though less common than venous oedema, is a well recognized cause of chronic swelling of the legs (Browse, 1982). Oedema of the extremities is called primary lymphoedema if no causes extrinsic to the lymphatic system can be found. It can present from birth or appear later in life. Secondary lymphoedema is associated with lymphatic obstruction as a result of post-inflammatory scarring, radical surgical procedures, radiation therapy, metastatic neoplastic disease involving the regional lymphnodes and filarial infestation (Kinmonth, 1972). Lymphoedema may be secondary to venous pathology such as varicosity and deep vein thrombosis (Kinmonth, 1972). Evaluation of the lymphatic system by traditional lymphangiography can be a difficult procedure and may involve complications. In addition, oedema may be exacerbated by lymphangiography. Moreover, venography may be required in some cases to differentiate it from swelling caused by chronic venous insufficiency. There is a need for a non-invasive method which may be easily repeated, which is complication free and which assesses lymphatic flow. Radionuclides allow a non-invasive and quantitative method with such techniques as interstitial 131 I albumin (Hollander et al, 1961) and intralymphatic "Tc m -HSA (Steckel et al, 1978). We have evaluated the clinical benefits of a quantitative radioisotope method Address correspondence to Masaaki Kataoka, MD, Department of Radiology, Ehime University School of Medicine, Shitsukawa, Shigenobu-cho, Onsen-gun, Ehime 79102, Japan. Vol. 64, No. 768
of external counting of interstitially injected "Tc m -HSA in patients with uterine cancer treated previously with operation and/or irradiation. Materials and methods Between May 1989 and September 1990, 26 patients who had undergone operation and/or irradiation to treat uterine cancer and five normal controls participated in the study. Of the 26 patients, 13 had undergone both surgery and post-operative irradiation. Six legs in four of these 13 patients developed lymphoedema. Six patients had been treated with irradiation alone. Four legs in two of the six patients developed lymphoedema. Seven patients had been treated with operation alone and none developed lymphoedema. The ages of the study participants ranged from 25 to 78 (mean, 56.5) years. External irradiation doses in the patients who had undergone both surgery and post-operative irradiation ranged from 40 to 60 Gy (mean, 48.7 Gy). All patients treated with radiation therapy alone had been given external and high dose-rate intracavitary irradiation except for one who, with Stage IVa (FIGO) disease, was treated with 60 Gy of external irradiation to the whole pelvis. The external irradiation dosage was 40-50 Gy with whole pelvis portals and 0-20 Gy with central shieldings. The dose of the intracavitary irradiation was 20-30 Gy at point A, which is 2 cm lateral to the uterine canal and 2 cm above the lateral fornix. A dose at point B, which is 3 cm lateral to point A, was calculated by simply adding the external irradiation dose to 30% of 1119
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the dose at point A by intracavitary irradiation. A dose at point A reflects the tumour dose and a dose at point B reflects the dose at the lateral pelvic wall (Tod & Meredith, 1953). A dose at point B, which is believed to be related directly to lymphatic damage by irradiation, was 56-69 Gy (mean, 61.5 Gy). Using a 25 gauge needle, 0.2 ml of tracer, corresponding to 7.4 MBq of 99Tcm-HSA having an ovalshaped particle size of 3.8 x 15 nm (molecular weight of 66,450), was injected into the interstitial tissues of the first and second interdigital plicae. The radioactivity at the injection site was subsequently counted with a gamma camera (gamma view-H, Hitachi Co., Ltd.), with a low energy parallel hole collimator for 3 min at 10 min (A) and at 3 h (B) after injection. The clearance of the "Tcm-HSA was defined as (1 -(B)/(A)) x 100 (%). The values of (A) and (B) were corrected for decay of the isotope. The radioactivity at 10 min was used as a baseline of the injected dose. The reason for the 10 min timing was that some patients showed bleeding from the injection sites and it took several minutes to stop this by compressing lightly with cotton. Furthermore, time activity curves at the injection sites have revealed that the difference in radioactivity at 10 min and immediately after the injection is minimal (Ohtake et al, 1983) and this difference is not clinically important. The timing of 3 h after injection was chosen for the second counting because a preliminary study on normal controls revealed that this was close to the disappearance half-time of the isotope. Until the first counting, patients remained at bed rest; after which they were invited to follow normal activity until the second counting. All patients were physically active. To compare mean figures, Welch's r-test or Student's r-test was used. Results "Tcm-HSA clearances in patients and in normal controls are shown in Fig. 1. Clearance in normal controls was significantly more rapid than those in other
OP + RT 3O.l±11.4%
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