[Brachytherapy with pulsed dosage. General considerations. Radiobiological considerations. First clinical experience in Mestre (Venice)]. / Brachiterapia con rateo di dose pulsato. Considerazioni generali. Considerazioni radiobiologiche. Prime esperienze cliniche a Mestre-Venezia.

The pulsed dose rate (PDR) brachytherapy technique is analyzed and compared with the low and high dose rate (LDR and HDR, respectively) techniques relative to therapy and management, considering the advantages and pitfalls of each technique. From a radiobiological viewpoint, PDR optimization is aimed at obtaining the same therapeutic results as with LDR and HDR relative to both tumor cell killing and possible late damage. PDR permits to administer the same nominal dose rates as with LDR and HDR, but with very different pulse intervals and length. March, 1995, through March, 1996, forty-two patients were treated with microSelectron PDR at the radiotherapy Department of Umberto I Hospital in Mestre (Venice). Twenty-two patients were irradiated on the vaginal vault, 14 on the anal canal, 4 on the breast, one on the endometrium and one on the urethra (the latter patient was a man). Dose rates were 250-300 cGy/h in the vaginal vault and 90 cGy/h in the other sites. Source-dwell interval in the applicators was 2.5 mm, dwelling time for each position ranged 6.8-122 s, 3-73 pulses were applied lasting 167-1958 s. The unit was reliable and the only problem was the need to recalibrate it every 5-6 applications because of computer memory saturation. Because of the short minimum follow-up (3 months), only the early reactions to treatment have been assessed: no toxicity was found in the vaginal vault, endometrium and breast. Low-grade proctitis was observed in 11 of 14 treated anal canals and another patient complained of more severe symptoms for two weeks; the disease progressed in two anal canal patients, as in the urethra patient. In conclusion, PDR brachytherapy appears a reliable technique whose early clinical results are encouraging.

[Epistaxis in Rendu-Weber-Osler disease. The role of brachytherapy]. / L'epistassi nel morbo di Rendu-Weber-Osler. Ruolo della brachiterapia.

Rendu-Weber-Osler disease is a rare autosomic disorder. Its most common symptom is epistaxis with transitory periods of remission and of ingravescent exacerbation compromising normal daily activities and forcing the patient to give up his normal life-style for prolonged periods of time. Often it proves difficult to control the recurrent epistaxis and the treatments available today are not always totally satisfactory. The authors present the results obtained using endonasal brachytherapy in 8 patients (13 treatments) epistaxis stemming from previously diagnosed Rendu-Weber-Osler disease. Brachytherapy employs thin plastic tubes, positioned in the nostril with the heaviest epistaxis. These tubes are then filled with Iridum192. The total dose, prescribed against the reference isodose, strictly adjacent to the nasal fossae mucosa, was 30 Gy over a period ranging from two to four days (average 2.5 days). Four patients required a second treatment to the controlateral nostril as the symptoms returned after a period ranging from 36 to 60 months (average 47.1 months). Only one patient required a second treatment in the same nostril 9 years later. The episodes of epistaxis were scored by symptom severity on a scale from 0 to 5. Of the 13 treatments administered (mono and bilateral treatments), 12 can be considered satisfactory as the epistaxis was reduced from the initial pre-treatment score of 4-5 to 2 or less (5 were reduced to 0, 3 to 1 and 4 to 2). In only 1 case was the score 3. Remission of symptoms lasted for a period ranging from 11 to 108 months with an average of 51.6 months. No complications arose from the use of brachytherapy. Only one patient required embolization 3 years after the endonasal brachytherapy treatment.

[Radiation treatment in the carcinoma of paranasal sinuses and nasal cavity]. / Il trattamento radiante nelle neoplasie dei seni paranasali e cavità nasali.

The authors evaluate 32 patients affected by paranasal sinuses and nasal cavity carcinoma observed at Orl-Rt Department of Oncologic Center at Umberto l(zero) Hospital in Mestre (VE), Italy from 1985 to 1994. Among these: 16 maxillary sinus, 10 ethmoid and 6 nasal cavity carcinomas. Histologic diagnosis showed squamous cell carcinoma in 15 cases, adenocarcinoma in 8 cases, lymphoma in 2 cases, transitional cell carcinoma in 2 cases, undifferentiated carcinoma in 2 cases and adenoidocistic carcinoma in 3 cases. The mean age was 64.5 years (range 46-88 years), and mean performance status was 80 (range 60-90). Four patients had lymphonodal involvement. Eleven patients were operated, eight of them radically. All patients were treated with radiation therapy. Treatment planning was performed using Theraplan V05-B program, on extensive number of CT scans. The minimal tumor dose was 50 Gy for patients operated radically and was 60 Gy with maximum of 73-80 Gy for the others. The follow-up is 39.7 months (range 10-108). Three patients treated with radical surgery developed local relapses, two of them died. Fourteen patients treated with non radical or diagnostic surgery and radiotherapy obtained local complete remission, five of them developed local relapses inside treatment volume. Ten patients died (eight for neoplastic disease). The 3 years, 5-years and 7-years overall survival are respectively 72% and 51%. The 5-years and 7-years disease free survival rate are respectively 48% and 19% with median at 3.7 years. Complication have been minimal. Only one patient affected by glaucoma had a severe and permanent reduction of the virus. The authors conclude that 2D and 3D treatment planning can assure a better accuracy for target definition and a better precision of the treatment with a reduction of complications.

[Brachytherapy in choroid tumors]. / Brachiterapia dei tumori coroidei.

Even though brachytherapy has been used for many years to treat choroidal tumors, it is not a widespread technique because it requires much organization and operators skills. The most common methods use 60Cobalt and 106Rutenium plaques, or custom-made plaques with 125Iodine loaded seeds. Another, less common, technique uses 192Iridium wires loaded on custom-made plaques. The technique we used to treat 4 retinoblastomas and 2 choroidal melanomas uses 192Iridium wires loaded on custom-made plaques. The applicator is made of a quick drying paste poured over a sphere the same size as the eye-ball: plastic tubes are inserted, according to preliminary dosimetric measurements, to house the Iridium wires. The applicator is positioned on the eye-ball corresponding to tumor site by surgery. The Iridium sources are inserted into the plastic tubes at the end of surgical placement: this afterloading technique guarantees maximal staff protection. 192Iridium (320 keV gamma emitter) allows the dose to be transmitted deeper than with 125Iodine (30 keV gamma-emitter) and 106Rutenium (3540 keV beta-emitter). Therefore, with Iridium, the dose delivered is lower on the eye-ball surface for the same tumor dose. On the other hand, the use of 60Cobalt (1250 keV gamma-emitter) gives the healthy surrounding tissues higher doses. To conclude, this method allows us to customize the application to every single case, to reach posterior sites, to ensure radioactive protection to staff thanks to afterloading and to obtain a good depth to surface dose ratio.

A new technique for endocavitary irradiation of the esophagus.

Recently, high-dose rate intracavitary irradiation has been used as a boost therapy or a palliative therapy in the treatment of the esophageal carcinoma. The new intraesophageal device is based on a modified Sengstaken-Blackemore tube. On the surface of the esophageal balloon of the S-B tube Cyponil tubes are fixed as iridium containers. The device is placed at the level of the neoplastic lesion. Treatment tolerance is good.

Ovarian function after pelvic lymph node irradiation in patients with Hodgkin's disease submitted to oophoropexy during laparotomy.

Staging laparotomy for Hodgkin's disease was carried out on 110 women in fertile age at the General Surgery Department of Padua Medical School from 1972 to 1977. An oophoropexy was done during the operation. According to the stage the patients underwent radiation therapy that was associated in some cases to chemotherapy. Complete evaluation was possible only in 66 patients. Eighteen out of the 66 had mantle field and para-aortic lymph node chain radiotherapy. One case of amenorrhoea (5.5%) and five pregnancies (27.8%), were found among them. Nineteen had the same type of radiotherapy with MOPP. 3 cases of amenorrhoea (15.8%) and 3 pregnancies (15.8%) were found. Five had total nodal irradiation (TNI) according to Kaplan and all of them had amenorrhoea (100%). Twenty four had TNI associated to MOPP with 24 cases of amenorrhoea (100%). Our results slightly differ from those of other Authors. They showed: 1) that the oophoropexy is not effective using standard surgical technique (probably because of the size of the central shielding) as it causes amenorrhoea in 100% of the cases; 2) the incidence of permanent amenorrhoea from chemotherapy with MOPP is the same as reported by other Authors; 3) the absence of teratogenic effects by chemotherapy in newborns of these patients.

[Endocurietherapy in cancer of the bladder. A new technique by implant of 192iridium with Cyponil tubes (author's transl)]. / Endocuriethérapie du cancer de la vessie. Proposition d'une nouvelle technique pars fils d'192iridium en tubes de Cyponil.

The Authors propose a new technique of interstitial implant in cancer of the bladder based on the direct implant of 192 Iridium with Cyponil tubes. The tubes are roughly 2 metres in length with a radioactive wire in one third of the tube length. These wires are kept in a lead container during the complete implantation of the tube. After opening the bladder the uncharged part of the tube is passed through the inner walls by means of surgical needles. The number of the tubes depends on the size of the tumour and they are placed parallel to each other. They are then drawn until the radioactive part covers the tumour site. One end of the Cyponil tube is then pulled through the urethra and stitched to the skin, the other end is drawn through the surgical incision and attached to the abdominal skin. A Folley catheter is put on the bladder is such a way as to keep it blown up. It is then sutured. A radiography is carried out so as to determine the dosage. At the end of the therapy the stitches of the Cyponil tubes are cut and are removed by extraction.