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V Vongtama

Publications and source records attributed to V Vongtama.

At least 19 recordsLinked to original sources
PubMed1999

Spinal cord dose is higher than expected in head and neck radiation.

Myelopathy is a feared consequence of radiation therapy. Risk factors are multifocal; therefore, total dose calculation is crucial. We evaluated the contribution of scatter radiation to obtain an accurate cumulative spinal cord dose. Twenty patients undergoing three field head and neck radiation by Cobalt or 6 MV Linac had a total cord dose calculated from direct and scatter radiation. The cord was removed from the radiation field at tumor doses no higher than 4,400 cGy. Total tumor dose ranged from 5,400-7,400 cGy (mean 6060). All patients achieved the prescribed dose and none were lost to follow up (mean 36 months). It was found that scatter radiation can contribute as much as 20% extra dose to the spinal cord. Mean extra dose was 9% (range 1%-20%). This additional dose ranged from 52-810 cGy (mean 339 cGy). No apparent difference was seen with Cobalt or Linac source. Our conclusion was that significant additional dose is delivered to the spinal cord by scatter radiation and that scatter may contribute more to the development of myelopathy than previously believed.

Cobalt Radioisotopes↗
PubMed1997

If you 'watch and wait,' prostate cancer may progress dramatically.

PURPOSE: Observation has been proposed as an option for localized prostate cancer. However, most series reporting on 'watch and wait' include patients treated by TUR or hormones that may affect results. We retrospectively reviewed the natural history of truly untreated prostate cancer and report the outcome for these patients. METHODS AND MATERIALS: From 1976 to 1992, 34 patients of median age 70 years (range 56-88) with biopsy proven localized adenocarcinoma of the prostate refused therapy. All had negative bone scan and none underwent TUR or hormone treatment. No patient was lost to follow-up (median 76 months). Failure patterns and survival were analyzed. RESULTS: At diagnosis 27 patients had palpable nodules (T2), of which 13 were well differentiated and 14 moderately differentiated. Seven had moderately differentiated T3 lesions. Mild prostatitis including nocturia, hesistancy, and urgency were reported in 16 T2 and 6 T3 patients. Within 36 months, local progression requiring therapy occurred in all T3, all T2 moderate and 5 of 13 T2 well-differentiated patients. Systemic progression occurred in 6 of 7 T3, 9 of 14 T2 (mod), and 2 of 13 T2 (well) patients. Overall 59% are alive, 26% succumbed to prostate carcinoma and 15% to other causes. CONCLUSION: Observation results in a high rate of local progression requiring intervention (77%) and excessive systemic disease development (50%) for patients with clinically palpable disease. Perhaps this strategy is viable for earlier stage lesions detected by PSA but it must be tested in a rigorous fashion before accepted.

Adenocarcinoma↗
PubMed1997

Radiation and chemotherapy improve outcome in oligodendroglioma.

PURPOSE: Oligodendroglioma is a rare central nervous system tumor which may occur in pure or mixed histology. This scarcity results in difficulty in defining optimal management, mainly due to a lack of outcome analysis. Results are further complicated because the reported series include patients treated before megavoltage radiation or computed tomographic (CT) scan development. This makes extrapolation of outcome difficult to apply to modern-era patients. We report results obtained by current treatment and evaluation. METHODS AND MATERIALS: Outcome of all 38 patients (age 5-70 years) pathologically diagnosed between 1975 and 1993 were reviewed. Pure lesions were seen in 14 cases, of which three were anaplastic. The remainder had mixed tumors, of which six contained anaplastic astrocytic elements. Each patient had undergone maximal debulking surgery, but all remained with residual disease on postoperative CT. RESULTS: For nonanaplastic lesions, no local failure was seen in any patient receiving postoperative radiation (60 Gy) and chemotherapy (vincristine, procarbazine, and carmustine). Follow-up ranged from 28 to 240 months (median 125; N = 6). No postoperative therapy or chemotherapy alone resulted in local failure in all nine patients at risk [time to failure (TTF): 2-40 months; median 25]. Radiation alone in doses of 50 Gy at 2 Gy per day resulted in all six patients failing (TTF: 12-52 months; median 36). Achieving 60 Gy at 2 Gy a day allowed five of eight patients to remain disease free (disease-free survival: 24-160 months; median 66), with three failing at 26, 40, and 60 months. All lesions containing anaplastic elements underwent postoperative radiation therapy (60 Gy) and chemotherapy, with five of nine patients alive and well (median disease-free survival: 48 months; range 28-120). CONCLUSION: The combination of radiation and chemotherapy increases local control of oligodendroglioma whether they contain pure, mixed, or anaplastic histology. Radiation alone may offer good local control as long as 60 Gy is delivered. Chemotherapy alone appears to delay TTF and may be useful for pediatric patients.

Adolescent↗
PubMed1995

Symptomatic acute mucositis can be minimized or prophylaxed by the combination of sucralfate and fluconazole.

Mucositis is a common and often serious acute morbidity when radiation is delivered to portals encompassing the oral cavity, pharynx, or esophagus. In an effort to minimize this side effect, the combination of sucralfate and fluconazole was prescribed to 40 patients. Half were given sucralfate, 1 g in suspension q.i.d. from the first week to the completion of radiation with fluconazole 100 mg., q.d. for 14 days initiated during the fourth week. The remaining individuals were placed on the same dosages of the two drugs dispensed simultaneously after symptoms appeared. For both cohorts the combination of sucralfate and fluconazole was effective in diminishing oral discomfort and pain associated with radiation and chemotherapy. When medication was delivered from the first week of therapy, all patients could achieve the prescribed radiation dose without treatment interruption and be maintained on a regular diet. The combination of drugs was also effective in minimizing symptoms once they appeared.

Drug Therapy, Combination↗
PubMed1987

Hydroxyurea plus pelvic radiation versus placebo plus pelvic radiation in surgically staged stage IIIB cervical cancer.

Forty-five evaluable patients with stage IIIB carcinoma of the uterine cervix were entered into a prospective, double-blind, randomized study to evaluate the possible radiation-potentiating properties of hydroxyurea. All patients were documented to be without para-aortic lymph node metastasis by pretherapy staging para-aortic lymphadenectomy. The original plan of therapy was for continuous therapy (200 rads/day) of 6,000 rads of pelvic radiation for 6 weeks plus intrauterine radium. However, 16 patients received 6,000 rads in 8 weeks by split-course therapy (2-week rest after 3,000 rads) plus radium. Twenty-nine patients received the planned continuous therapy. The median dose of pelvic radiation for patients who received continuous therapy or split-course radiation was 6,000 rads. Leukopenia (WBC less than 2,500/mm3) was significantly increased in the patients given hydroxyurea as compared to those given placebo (P less than .001). There was no statistically significant difference relative to anemia, thrombocytopenia, radiation skin reaction, diarrhea, or radiation-induced complications requiring surgical correction. The estimated 5-year progression-free survival rate for the combined, continuous, and split-course radiation therapy hydroxyurea patients was 60%, and its was 52% for the corresponding placebo patients (P = .49). However, the estimated 5-year progression free survival rate for the correctly treated patients (continuous therapy) was 91% for the hydroxyurea group and 60% for the placebo group (P less than .06).

Adult↗
PubMed1983

Hydroxyurea: a radiation potentiator in carcinoma of the uterine cervix. A randomized double-blind study.

From June, 1972, to December, 1976, 40 patients with FIGO (International Federation of Gynaecology and Obstetrics) Stage IIB carcinoma of the uterine cervix were entered into a prospective, double-blind, randomized study to evaluate the possible radiation-potentiating properties (i.e., improved survival) of the S-phase cell cycle-specific inhibitor of DNA synthesis, hydroxyurea. All patients were documented to be without aortic lymph node metastasis by pretherapy staging para-aortic lymphadenectomy. All 40 patients were followed up for longer than 5 years (5.2 to 9.2 years) or until death. The double-blind code was not broken until all patients had been followed up for a minimum of 2 to 5 years. Leukopenia (white blood cell count less than 2,500 mm3) was significantly increased in the patients given hydroxyurea as compared to those given placebo (P less than 0.0001). There was no statistically significant difference relative to anemia, thrombocytopenia, radiation-induced skin reaction, and radiation-induced intestinal reaction between the patients given placebo or those given hydroxyurea. Life-table survival for the patients given hydroxyurea was 94% as compared to 53% for the patients given placebo (P = 0.006). Only one (5%) patient given hydroxyurea died of cervical cancer. Of the other patients who died in the group given hydroxyurea, all were confirmed by postmortem examination to have been without recurrent cervical cancer. In contrast, 45% (nine) of the patients given placebo died of cervical cancer.

Adenocarcinoma↗
PubMed1977

Hydroxyurea as a radiation sensitizer in women with carcinoma of the uterine cervix.

Hydroxyurea was evaluated as a possible radiation sensitizer in 130 evaluable women with Stages IIB and IIIB (International Federation of Gynecology and Obstetrics) carcinoma of the uterine cervix. This was a prospective double-blind randomized study in which hydroxyurea or placebo was compared in conjunction with continuous or split-course radiation therapy. Of all patients with Stage IIB cancer without biopsy proof of aortic node metastasis, a significant improvement in survival (P less than 0.01) was achieved in the hydroxyura group (74.0%) as compared to the patients receiving placebo (43.5%). In women with Stage IIIB cervical cancer there was a trend toward longer survival in those receiving hydroxyurea (52.1%) as compared to those receiving placebo (33.3%). However, there was a statistically significant improvement in survival in those women with Stage IIIB cervical cancer who had staging done at operation, were found to have negative para-aortic nodes, and subsequently received continuous radiation therapy (90.9%) as compared to those receiving split-course therapy (29.4%) (P = 0.005).

Clinical Trials as Topic↗
PubMed1976

Dysgerminoma of the ovary: radiation therapy for recurrence and metastases.

Nine cases of dysgerminoma are reported. Five patients developed recurrence of disease in either the pelvis or metastatic sites including the lung and brain. The metastatic disease was controlled by a radiation dose of 2,000 to 3,000 rads during three to four weeks in four of the patients. The excellent response of dysgerminoma to radiation warrants an optimistic prognosis and vigilant follow-up since metastatic disease can be controlled by moderate radiation doses.

Adolescent↗
PubMed1976

Treatment, results and prognostic factors in stage I and II sarcomas of the corpus uteri.

One-hundred and four cases of Stage I and II uterine sarcomas treated at Rosewell Park Memorial Institute over a 27 year period are reviewed. Included are 30 cases of mixed mesodermal tumor, 27 cases of carcinosarcoma, 25 cases of endometrial stromal sarcoma, and 22 cases of leiomyosarcoma. Prognostic factors were found to include histologic classification, stage, uterine size, depth of myometrial invasion, and type of treatment. Endometrial stromal sarcomas had the best over-all prognosis. Radiation therapy alone was inadequate treatment, but was of adjunctive value to surgery in terms of increasing survival and decreasing pelvic recurrences in patients with endometrial stromal sarcoma, mixed mesodermal tumor, and carcinosarcoma. Patients with leiomyosarcoma did not benefit from adjunctive radiation therapy.

Adult↗
PubMed1975

Sequential therapy for advanced ovarian adenocarcinoma: operation, chemotherapy, second-look laparotomy, and radiation therapy.

In an attempt to improve the survival rates in women with advanced ovarian adenocarcinoma (abdominal spread), they were treated with sequential therapy. This consisted of operation followed by chemotherapy, second-look exploratory laparotomy, and finally whole-abdomen irradiation. Only those patients who had a complete clinical response to chemotherapy and subsequently underwent a second operation and irradiation were evaluated. Seventy-five per cent of the patients had recurrent cancer within the treated area after sequential therapy was completed. Morever, of four patients with no gross residual cancer after the second operation, three had cancer recurrences within the treated area. It is concluded that methods of treating advanced ovarian adenocarcinoma other than sequential therapy must be found.

Adenocarcinoma↗
PubMed1975

End results of radiation therapy, alone and combination with 5-fluorouracil in colorectal cancers.

The authors retrospectively analyzed the results of irradiation in 148 cases of primary inoperable and recurrent adenocarcinoma of the colon and rectum treated at the Department of Radiation Therapy, Roswell Park Memorial Institute between 1962 and 1970. This group includes 95 recurrences and 53 inoperable primaries. Uninterrupted radiotherapy was used in 118 cases and split-course technique in 30 cases. Eleven patients received combined radiotherapy and surgery. Seventy-eight patients received a combination of 5-fluorouracil (5-FU) and irradiation. The response rate and survival of individual groups is discussed in detail. This study indicated that perineal recurrences should receive whole pelvic irradiation in addition to perineum field. Split-course technique appeared to yield a better survival than the uninterrupted course. The best 5-year survival rate (64%) is found in the group treated with a combination of radiation and surgery. For locally advanced, inoperable cancers, split-course technique, combined 5-FU and irradiation gave the best results, achieving longer palliation with improved quality of life and sometimes yielding cure (5-year survival).

Colonic Neoplasms↗
PubMed1975

Primary treatment of advanced ovarian adenocarcinoma, stages III and IV.

In an attempt to improve the response rate and hopefully the survival rate in women with advanced ovarian adenocarcinoma, three new modalities of therapy for ovarian adenocarcinoma were undertaken in 97 women. Sequential therapy consisted of surgery followed by chemotherapy, second-look laparotomy, and subsequent whole abdominal radiation. Eight women exhibiting a complete clinical response to chemotherapy were subjected to this treatment. However, only one woman (12%) is surviving without evidence of tumor recurrence. Concomitant therapy consisted of external radiation and single alkylating agent chemotherapy in 23 women. Again, the survival was poor: a 5-year survival of 8% without tumor recurrence. The third treatment modality consisted of a randomized study of 66 patients in whom single agent therapy with melphalan was compared with multiple agent therapy consisting of cyclophosphamide, dactinomycin, and 5-fluorouracil. In those women with stage III and IV serous adenocarcinoma of the ovary, a 63% response rate was obtained in patients receiving triple chemotherapy as compared to a 45% response rate in those receiving melphalan. Moreover, 40% of the group given triple chemotherapy exhibited a complete response as compared to only 18% in the group given melphalan.

Adenocarcinoma↗