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G Pizzi

Publications and source records attributed to G Pizzi.

34 records · Page 2Linked to original sources
PubMed1989

[Templates for curietherapy of the oral cavity and their dosimetric use].

Flexible 192Ir wire implants are commonly used for the treatment of some types of cancer in the oral cavity. A modified technique of plastic tubes is here presented which aims at correctly positioning the active wires with thin plastic templates. Possible sources of error are examined and their consequences on the dose distribution around the implant are analyzed. In most cases control dosimetry matches the provisions satisfactorily. It may be thus concluded that the use of templates allows good and reproducible results to be obtained in the brachytherapy of the oral cavity.

Brachytherapy↗
PubMed1988

Is prophylactic para-aortic irradiation worthwhile in the treatment of advanced cervical carcinoma? Results of a controlled clinical trial of the EORTC radiotherapy group.

From November 1977 to July 1981, 441 patients with cervical carcinoma were randomized between pelvic irradiation and pelvic and para-aortic irradiation. Included were patients with stage I and IIB with proximal vaginal and/or parametrial involvement with positive pelvic lymph nodes either on lymphangiogram or at surgery, and stage IIB with distal vaginal and/or parametrial involvement and III regardless of pelvic node status on lymphangiogram. Patients with clinically or surgically involved para-aortic nodes were not included. The external beam dose to the para-aortic area was fixed at 45 Gy. There was no statistically significant difference between the two treatment arms in terms of local control, overall distant metastases and survival with no evidence of disease (NED), although the incidence of para-aortic metastases and distant metastases without tumor at pelvic sites was significantly higher in patients receiving pelvic irradiation alone (pelvic group). The 4-year NED survival rate was 51%. The incidence of severe digestive complications was significantly higher in patients receiving para-aortic irradiation (para-aortic group). Routine para-aortic irradiation for all high risk patients with cervical carcinoma is of limited value, but patients with a high probability of local control can benefit from extended field irradiation, despite an increase in severe digestive complications.

Aorta↗
PubMed1981

[Dosimetry of the bladder and the rectum: comparison between the measured and calculated dose (author's transl)].

The authors examine 62 cases of curietherapy in the deep vagina on 21 cases of utero-vaginal applications and make a comparison between two dosimetric methods used to measure the dose to the rectum and to the bladder: the direct measure by the Siemens Gammameter dosimeter and the Chassagne-Horiot method. Very large differences were found between the doses evaluated by the two methods. The values with the direct measure were often found to be higher than the calculated ones. When the measurements were done by different doctors, the result was almost the same.

Brachytherapy↗
PubMed1980

Exophthalmos from aneurysmal bone cyst of the orbital roof.

An aneurysmal bone cyst of the orbital roof, causing a monolateral exophthalmos in a 15-month-old child with no previous history of head injury, was operated upon and histologically misdiagnosed as a giant cell tumor. Radiation treatment in a dosage (3,740 rad) appropriate for the latter diagnosis apparently caused a massive calcification of the residual mass with persisting exophthalmos. At a second operation the lesion was removed completely and a radical change in the histopathological features was found. 12 years after surgery, there is no evidence of residuals upon roentgenographic and CT scan examinations and the exophthalmos has practically disappeared, while there is a normal visual function in the affected eye. Some points of histopathological and gross pathological differential diagnosis between aneurysmal bone cysts and giant cell ("myeloplaxis") tumors are discussed.

Adolescent↗
PubMed1979

Time dependence of hematoporphyrin distribution in selected tissues of normal rats and in ascites hepatoma.

The distribution of hematoporphyrin was determined in normal rats and in rats bearing ascites hepatoma as a function of time after i.p. injection of 10-20 mg/kg of dye. In both cases, hematoporphyrin displayed a high affinity for the tumor cells. At 20 mg/kg, the maximum difference between the amount of hematoporphyrin accumulated in the tumor and in the liver was obtained at 12 h after injection (tumor/liver ratio = 28). Our results suggest that hematoporphyrin is almost exclusively metabolized in the liver and excreted via the biliary tract, whereas only minor amounts are metabolized in the tumor cells. Moreover, the binding between the porphyrin and tumor cells is competitive with serum protein binding.

Animals↗
PubMedDate not supplied

[Treatment with 32P of carcinoma of the prostate (author's transl)].

Twenty-eight patients affected with disseminated prostate cancer, which proved hormone resistant (after castration and oestrogen administration), have undergone combined treatment with Testosterone (for 13 days) and 32P (for the last 7 days of the Testosterone treatment). During the initial fase of the treatment (Testosterone only), 14 patients experienced pain exacerbation and/or fever and one experienced immediate improvement. The exacerbation quickly disappeared following 32P administration, and 26 of the patients had distinct improvement at some time during or after treatment, with a mean remission duration of 3 months and mean survival rate of 7 months. No lytic or soft part deposit showed improvement; improvement was noticeable only in the mixed type or osteo-sclerotic metastases. This observation suggests that the androgen stimulates uptake of the isotope not inside the tumor cells but in the bone matrix around the tumoral deposit. The patient who showed very early improvement had a subsequent relapse on oestrogens, but later responded to the androgen alone.

Humans↗
PubMedDate not supplied

Hyperbaric oxygen in diabetic gangrene treatment.

We treated a group of 18 hospitalized adult diabetic patients (all with retinopathy, 17 with symptomatic neuropathy, and 6 with macroangiopathy) presenting with gangrenous lesions of the foot by a combined regime consisting of strict metabolic control, daily debridement of necrotic tissues, and daily hyperbaric oxygen (HBO) treatments given in a multiplace oxygen chamber. Another group of 10 adult subjects with comparable foot lesions (all with retinopathy, 9 with symptomatic neuropathy, and 4 with macroangiopathy) was treated in exactly the same way except for HBO. In the test treatment group, 16 patients were healed, and the remaining 2 showed no improvement and later underwent amputation. The number of HBO treatments required for healing was significantly related to the size of gangrenous lesions. In the non-HBO-treated group, only 1 patient improved, 5 of 10 showed no change, and 4 of 10 worsened until leg amputation was unavoidable. Comparison of the two groups by chi 2-test revealed a highly significant difference (P = .001). In practical terms, HBO treatment drastically reduced leg amputations in patients so treated in the last 3 yr compared with earlier and current figures for patients not receiving HBO treatment.

Adult↗
PubMedDate not supplied

[The use of a single anterior oblique field in the treatment of T1aN0 vocal cord neoplasms. Results and comparison with other technics].

From 1985 through 1993, 113 patients affected with T1N0 glottic cancer were treated with irradiation alone at the Radiotherapy Department of Umberto I Hospital in Mestre, Italy. An anterior oblique beam of 12 MV X-rays (LINAC) or gamma-rays of a Cobalt unit were used. Dose distribution was always studied on CT scans and with a Theraplan V05-B, Theratronics. Patients age ranged 40-92 years (mean: 64.7 years) and they were mostly males. The dose was always 60 Gy/30 fractions referred to the 90% isodose. The dose to the target volume ranged 90-105%, with a mean of 99%. The follow-up ranged 26 to 98 months; the median and the mean are 38 and 40 months, respectively. Six patients had local relapses and were all operated on: cordectomy was performed in 3 of them and laryngectomy in the other 3. Radiation therapy yielded 94.7% disease control; the lesion was ultimately controlled in 100% of patients after surgical salvage. Fifteen patients died, all of them of non-neoplastic disease. The authors compared this technique with those most frequently used, i.e., wedged opposed lateral fields and wedged anterior oblique beams, and observed that it allows minimal volumes to be irradiated with maximal doses and yields results. Wedged beams are not necessary with this technique. The authors consider irradiation the treatment of choice for early glottic cancer and believe that surgery, with the conservative approach if feasible, should be limited to relapses.

Adult↗
PubMedDate not supplied

[The polycentric multiple arc complanar technic, or telebrachytherapy. A 4-year experience (an innovative way for the local control of solid neoplasms)].

The coplanar polycentric multiple 180 degrees single arc and narrow beams technique (PMA) allows high radiation doses to be delivered to the target, with similar dose distribution to that of brachytherapy. Since 1990, more than 100 patients have been treated: 80 had NSCLC, 12 had epidermoid head and neck (oral cavity and oropharynx) cancers, 8 brain tumors, 4 esophageal cancers and, sporadically, other patients had many other kinds of tumors, e.g., Hodgkin's and non-Hodgkin's lymphomas and sarcomas. X photons of a 12-MV Linac have always been used. NSCLC patients are assessable for local control, toxicity and survival, while the other patients only for local control and/or toxicity. As for 31 stage I-II lung cancer patients, CR has been observed in 82.8% of them and PR in 13.8%; the response was always assessed with chest radiography, CT, FBS, cytology and/or histology. The overall actuarial survival rate is 71% at 40 months, the disease-free survival rate is 75% and the local progression-free survival rate is 94%. As for 49 stage-III patients, CR has been observed in 40% of them and PR in 56%. The overall disease-free survival is 10% at 28 months (median survival: 14.37 +/- 0.6 months). The disease-free survival rate is 23%. The local progression-free survival rate is similar to the overall survival rate, which seems to prove the very high metastatic spread of this disease in advanced stages. Twelve head and neck cancer patients have been treated, 5 of them in stage II and 7 in stage IV. CR has been observed in all the patients in lower stages (100%), in 4/7 patients in stage IV (57%) and in 4/5 patients (80%) in the T4N0 subgroup. The response of brain tumors treated with the PMA technique is difficult to assess because radiographic, CT and MR images are difficult to correlate with patients clinical status. The patients in our series are still alive, with a medium follow-up of 7 months (range: 2-16 months). A longer follow-up is necessary before any other considerations on the effectiveness of this method can be made. This technique was used on the patients who were not eligible for the other techniques with high doses delivered to the tumor, because of its volume and/or shape. Four esophageal cancers were treated with palliative intent, because of absolute dysphagia, in alternative to HDR brachytherapy. All these patients have obtained symptom remission.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗