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At least 145 records · Page 8Linked to original sources
PubMed1984

Adjuvant therapy for carcinoma of the colon and rectum.

Because all types of cancer therapy are most effective when the tumor burden is small, adding adjuvant cancer treatment to surgical excision has great merit both in theory and experimentally. Even though large numbers of patients with large bowel cancer have been entered into various types of experimental trials over the past 25 years, the potential of multimodal cancer therapy has only been examined in a superficial manner at best. If this therapeutic approach had any substantial effectiveness, it would have long since become apparent. Surgical therapy is effective, with a five-year survival of 50%, and the various adjuvant therapies have shown only modest effectiveness when tested on patients with measurable disease. 5-Fluorouracil, with a response rate in measurable disease of approximately 20%, is the only consistently effective cancericidal drug, and its combination with other agents has thus far shown no increase in this response rate. Currently, available data would indicate a modest survival benefit from the use of postoperative 5-fluorouracil, particularly in patients with positive lymph nodes. There are a number of trials in progress studying the effectiveness of multiple drug combinations as well as combining chemotherapy with radiotherapy and/or immunotherapy in the adjuvant setting. Preliminary studies would suggest a benefit from infusing chemotherapy into the liver in the immediate postoperative period, although there has been no evidence substantiating improved survival from this approach. The multiple approaches for generating an effective immunologic response continue to be experimental and have little use in other than a highly controlled experimental environment. The use of radiotherapy as an adjuvant to surgery has been confined largely to patients with low-lying rectal cancer. There is substantial evidence that high-dosage radiotherapy for large bulky and fixed rectal cancer will result in shrinkage of the lesion, permitting more satisfactory surgical resection and decreasing the incidence of perineal recurrence. Evidence would also suggest that moderate-dosage preoperative radiotherapy may sufficiently alter cancer cells so that cells disseminated at the time of operation are no longer capable of growth. It has also been demonstrated that preoperative radiotherapy decreases the incidence of positive lymph nodes. Modest increase in survival following preoperative radiotherapy has also been demonstrated in numerous trials. Postoperative radiotherapy has not been tested for a sufficient period of time to either demonstrate its effectiveness or safety.(ABSTRACT TRUNCATED AT 400 WORDS)

Antineoplastic Agents↗
PubMed2006

[Improvement of postoperative radiotherapy in the complex treatment of stage II-III cervical cancer].

Clinical data on the management of squamous-cell cervical carcinoma stage II-III FIGO are presented. At stage I, treatment included neoadjuvant polychemotherapy (NACT)--cisplatin 100 mg/m2, carboplatin 450 mg/m2 in conjunction with 5-FU 250 mg/m2 or paclitaxel 135 mg/m2. According to protocol, two identical courses of NACT were given, at 21-28 day interval, followed by extended extirpation of the uterus (Wertheim). Immediate results and complications caused by preoperative radiotherapy, important for postoperative one, were evaluated, concepts and strategies for postoperative intracavitary and distant radiotherapy worked out. To optimize radiotherapy, dosage was reduced by 10% or daily single target dose of intracavitary and distant irradiation split per 24 hrs, indications for preoperative radiotherapy variants were extended, and local dosage escalation in areas of lymphocyst or hematoma renounced. Overall survival was 85%, recurrence-free--77.5%.

Adult↗
PubMed2000

[Postoperative radiotherapy in lung cancer: comments on several randomized trials or the contribution of well-conducted radiotherapy].

Postoperative radiotherapy is classically proposed after surgical resection in case of a high risk of local recurrence (incomplete resection and nodal invasion especially mediastinal). Its interest was shown by non-randomized trials. Nevertheless, several randomized trials and one meta-analysis of them have recently questioned the contribution of radiotherapy. We analyze here these trials then the meta-analysis, emphasizing certain methodology problems such as the noninclusion of certain therapeutic trials and differences in radiotherapy dosages and techniques. In our opinion, excessive toxicity observed in certain trials can be attributed to technical errors; if well conducted, postoperative radiotherapy improves survival in operated patients when there is a high risk of local reccurence. This affirmation is based on a comparison of long term results of 347 non randomized cases with Port Meta-Analysis randomized cases and GETCB trial randomized cases.

Clinical Trials as Topic↗
PubMed1996

Radiation doses of yttrium-90 citrate and yttrium-90 EDTMP as determined via analogous yttrium-86 complexes and positron emission tomography.

Yttrium-90 is used for palliative therapy for the treatment of skeletal metastases, but because it is a pure beta- emitter, data on the pharmacokinetics and radiation doses to metastases and unaffected organs are lacking. To obtain such data, the present study employed yttrium-86 as a substitute for 90Y, with detection by positron emission tomography (PET). The study compared the properties of two different 86Y complexes - 86Y-citrate and 86Y-ethylene diamine tetramethylene phosphonate (EDTMP) - in ten patients with prostatic cancer who had developed multiple bone metastases (the ten patients being divided into two groups of five). Early dynamics were measured up to 1 h post injection (p.i.) over the liver region, followed by subsequent whole-body PET scans up to 3 days p.i. Absolute uptake data were determined for normal bone, bone metastases, liver and kidney. Radiation doses were calculated according to the MIRD recommendations. Based on the pharmacokinetic measurements of the distribution of the 86Y complexes, it was possible to calculate radiation doses for the bone metastases and the red bone marrow delivered by complexes containing 90Y. In 1 cm3 of bone metastasis, doses of 26+/-11 mGy/MBq and 18+/-2 mGy/MBq were determined per MBq of injected 90Y-citrate and 90Y-EDTMP, respectively. The doses to the bone marrow were 2.5+/-0.4 mGy/MBq for 90Y-citrate and 1.8+/-0.6 mGy/MBq for 90Y-EDTMP. 86Y and PET provide quantitative information applicable to the clinical use of 90Y. This method may also be useful for the design of other 90Y radiopharmaceuticals and for planning radiotherapy dosages.

Aged↗
PubMedDate not supplied

[Ewing's sarcoma. Results of treatment in 16 consecutive cases].

In the period January 1974-August 1981, 16 previously untreated cases of Ewing's Sarcoma have been diagnosed at the Giannina Gaslini Children's Hospital Genova. Eight were male, eight female. Median age at diagnosis was 11 years. Two patients presented with a unique metastatic lesion, in the right lung and in an illiac lymph node, respectively. Fourteen patients have been initially treated with local radiotherapy (dosages ranging form 4,800 to 6,600 rads) in association with antiblastic polichemotherapy utilizing 4 drugs (Adriamycin, Actinomycin D, Vincristine, Cyclophosphamide). The Rosen et al.'s T-2 protocol was adopted, modifying the initial phase in order to give more weight to Adriamycin and reduce the toxic effects related to radio-chemotherapy combination. Two patients bearing a costal primary were immediately treated with a more complex and aggressive chemotherapy (T-6 Protocol), followed by local irradiation (in one case preceded by surgical ablation) and then chemotherapy again (T-2 protocol, second phase) for 10 months. Treatment determined a fast subjective relief in the 13 symptomatic patients. All 16 cases achieved a status of complete remission. Four of them subsequently relapsed: locally in two, in distant sites in the remaining 2. All 4 died 12-27 months form diagnosis. Twelve patients are presently alive without evidence of disease at 3-92 months (median 37 months) following diagnosis. Treatment has caused early and delayed toxicity in all cases. However, the entity of these complications varied considerably from one patient to an other. Age at diagnosis and site of primary tumor were the factors most relevant in this respect.

Adolescent↗