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T Pajak

Publications and source records attributed to T Pajak.

At least 19 recordsLinked to original sources
PubMed1999

Final report of Intergroup Trial 0122 (ECOG PE-289, RTOG 90-12): Phase II trial of neoadjuvant chemotherapy plus concurrent chemotherapy and high-dose radiation for squamous cell carcinoma of the esophagus.

PURPOSE: To determine the outcome of neoadjuvant chemotherapy followed by concurrent chemotherapy plus high-dose radiation therapy in patients with local/regional squamous cell carcinoma of the esophagus. METHODS AND MATERIALS: Forty-five patients with clinical Stage T1-4N0-1M0 squamous cell carcinoma were entered on a prospective single-arm study, of which 38 were eligible. Patients received 3 monthly cycles of 5-FU (1000 mg/m2/24 h x 5 days) and cisplatin (100 mg/m2 day 1; neoadjuvant segment) followed by 2 additional monthly cycles of 5-FU (1000 mg/m2/24 h x 5 days) and cisplatin (75 mg/m2 day 1) plus concurrent 6480 cGy (combined modality segment). The median follow-up in surviving patients was 59 months. RESULTS: For the 38 eligible patients, the primary tumor response rate was 47% complete, 8% partial, and 3% stable disease. The first site of clinical failure was 39% local/regional and 24% distant. For the total patient group, there were 6 deaths during treatment, of which 9% (4/45) were treatment related. The median survival was 20 months. Actuarial survival at 3 years was 30%, and at 5 years, 20%. CONCLUSION: This intensive neoadjuvant approach does not appear to offer a benefit compared with conventional doses and techniques of combined modality therapy. However, high dose radiation (6480 cGy) appears to be tolerable, and is being tested further in Intergroup Trial INT 0123.

Adult↗
PubMed1996

[Dioxins in the municipal waste incineration process--threats, norms, actual situation, counter-actions].

Within the group of organochlorine, posing a positive danger the natural environment, the most interesting, controversial and objectionable for ecology++ are dioxins. In professional journals the name "dioxins" is a simplification which commonly refers to a certain group of organic chemical compounds, or, to be more precise, their derivatives called polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). The latest research has confirmed the existence of yet another group of similar character polybrominated and polyfluorinated. Though other sources of industrial dioxins emission exist their first and foremost sources are incineration processes, in particular the processes of municipal, hospital and other toxic and chemical waste incineration. The compounds mentioned above, but all their isomers--tetrachlorodibenzodioxin (TCDD), tetrachlorodibenzofuran (TCDF)--are highly toxic and lack of emission control may prove highly hazardous for health and natural environment. The paper discusses a number of issues connected with dioxin emission during incineration of solid and gaseous municipal waste. A balance of the transport of dioxins between their source (i.e. the waste), through the process of their incineration and recombination, to the final stage--their presence in solid and gaseous incineration products. Following that European legislature on dioxin emission is discussed together with the presentation of state-of-the-art installations for reducing the amount of dioxins in exhausted gasses. Most of the research has been based on author's own observations and research done while taking active part in operation of selected waste incineration plants. The remaining data have been gathered from reference papers on current experiments carried out in European waste incineration plants. Summing up, the paper maintains that the incineration of municipal waste in state-of-the-art installations conforming to emission norms does not endanger the natural environment with dioxins emitted in exhaust gasses. This danger is, however, present in the solid incineration products due to high concentration of dioxins there. Operators are fully aware of this fact and attempt to counteract it. The awareness of presence of dioxins emitted in the process of waste incineration should be decisive factor while choosing technology and installation, which fitted appropriate cleanup equipment will guarantee level of dioxin emission safe for the environment and conforming to the norms of dioxin emission.

Air Pollution↗
PubMed1993

Effects of bolus volume, viscosity, and repeated swallows in nonstroke subjects and stroke patients.

This study examined the effects of bolus volume and viscosity and the variability of repeated swallows in ten stroke patients and ten age-matched nonstroke subjects. The ten stroke patients demonstrated single unilateral cortical (three subjects), subcortical (six subjects), or brainstem (one subject) infarcts on computed tomography or magnetic resonance imaging scans at three weeks post-ictus. All subjects underwent videofluoroscopic swallow studies in which seven temporal pharyngeal swallow measures were examined. Despite the dissimilarity in lesion locations, the swallow physiology in the stroke patients was relatively homogeneous, ie, no swallowing disorders severe enough to prevent oral intake. As bolus volume increased, pharyngeal delay time diminished in stroke patients, but not in nonstroke subjects. Increasing bolus volume affected three other pharyngeal swallow measures similarly in nonstroke and stroke subjects: laryngeal closure durations and cricopharyngeal (CP) opening durations increased and duration of tongue base contact to posterior pharyngeal wall decreased. On viscosity comparisons (liquid vs paste), both subject groups displayed longer duration of base of tongue contact to posterior pharyngeal wall. On paste swallows, nonstroke subjects had longer CP opening and lower swallow efficiency, whereas stroke patients did not. This study found no statistically significant learning/repetition effect for repeated swallows in either subject group, or both groups combined.

Adolescent↗
PubMed1991

A randomized prospective trial comparing full dose chemotherapy to 131I antiferritin: an RTOG study.

A previously reported Phase I/II multimodality program for non-resectable hepatocellular cancer began with external beam-radiation and chemotherapy, followed by administration of 131I antiferritin-specific radioimmunoglobulin and led to a 48% remission (7% complete remission and 41% partial remission). Survival and response depended on alpha fetoprotein status. AFP+ patients had a median survival of 5 months; AFP- patients had a median survival of 10.5 months. No acute effects occurred relative to treatment with radiolabeled antibody. A randomized prospective study was designed to compare full dose chemotherapy consisting of 60 mg/m2, doxorubicin and 500 mg/m2 of 5-fluorouracil administered every 3 weeks, to 131I antiferritin administration every 8 weeks and allowed for crossover treatment if tumor progression occurred. Overall, radiolabeled antibody administration and full dose chemotherapy led to equivalent partial remission rates (22-30% vs 23-25%) and survival rates compared to chemotherapy (6 month median; AFP+ 5 months; AFP- 10 months). The most important new observations were the response in AFP- patients who, following chemotherapy failure, achieved remission using 131I radiolabeled antibody (7/11) and a subset of patients (7%) who were treated with radiolabeled antibody and converted from non-resectable to resectable status followed by surgical excision.

Adult↗
PubMed1991

Randomized phase III study comparing irradiation and hyperthermia with irradiation alone in superficial measurable tumors. Final report by the Radiation Therapy Oncology Group.

A total of 307 patients with superficial measurable tumors were registered on a Radiation Therapy Oncology Group (RTOG) protocol involving fractionated radiation therapy, either alone or followed immediately by hyperthermia (42.5 degrees C, 45-60 min). Overall complete response (CR) was observed in 30% of the lesions treated with radiotherapy (RT) and 32% of those receiving RT and heat. Response was found to be significantly related to both maximum tumor diameter (less than 3 or greater than or equal to 3 cm) and site/histology (breast/adenocarcinoma, head and neck/squamous, or other site/histologies). In tumors less than 3 cm in diameter in the breast, trunk, and extremities, a better CR rate was noted with irradiation and heat (62 and 67%) than with irradiation alone (40 and 0%). However, in the head and neck there was only minimal difference in CR with irradiation alone or combined with hyperthermia (50 vs 38%). In lesions less than 3 cm treated with irradiation and heat, there was improved local control. In lesions greater than 3 cm, there was no difference in local control between the two treatment arms. The higher response rate in patients with smaller lesions (less than 3 cm) may be explained by the fact that these tumors are easier to heat. Problems in correlating tumor response with quality of heating include less than optimal heating in larger lesions and the limited ability of current thermometry to map the temperature distribution in a tumor. Acute and late toxicities in both treatment arms were comparable, except for an overall 30% incidence of thermal blisters in the heated tumors.

Adenocarcinoma↗
PubMed1991

Prospective comparison of vaginal and abdominal sonography in normal early pregnancy.

Vaginal and abdominal sonography were prospectively compared in 309 consecutive pregnancies of which 175 were normal. Two sonographic criteria of normal were analyzed: (1) the presence of an embryo compared with average gestational sac size and (2) the presence of embryonic cardiac activity compared with crown-rump length. Vaginally, 100% (160/160) of embryos were visualized when the average sac diameter was greater than or equal to 12 mm. Abdominally, an embryo was noted in 99.2% (123/124) of gestational sacs greater than or equal to 27 mm. Vaginal sonography revealed cardiac motion in all embryos of greater than or equal to 5 mm (149/149 cases); abdominal sonography revealed cardiac activity in 100% (132/132) of embryos with a crown-rump length of greater than or equal to 9 mm. One-third of normal embryos less than 5 mm crown-rump length did not demonstrate cardiac activity. The study demonstrates through objective comparison that vaginal sonography is superior to abdominal sonography for detection of an intrauterine embryo and its cardiac activity before 8 menstrual weeks. The diagnosis of embryonic demise should not be made by vaginal sonography in embryos measuring less than 5 mm crown-rump length without a heartbeat, and an empty gestational sac of less than 12 mm average diameter should not be diagnosed as blighted ovum by vaginal scans. In these cases follow-up vaginal sonography is suggested.

Abdomen↗
PubMed1989

Quality assurance problems in clinical hyperthermia and their impact on therapeutic outcome: a Report by the Radiation Therapy Oncology Group.

Since February 1981, 300 patients with superficial measurable tumors were randomized on an RTOG protocol (81-04) involving fractionated radiation therapy (4.00 Gy twice weekly for a total of 32.00 Gy), either alone or followed immediately by hyperthermia (42.5 degrees C, 60 min). This is a report of 218 eligible patients with single lesions: 107 treated with radiotherapy alone (RT), 111 with radiotherapy plus hyperthermia (RT + HT). Only 56% of the 24 tumors less than 3 cm and 36% of the 53 lesions larger than 3 cm received what was felt to be "adequate" therapy (greater than or equal to 29 Gy and 8 heating sessions). Overall complete response (CR) was observed in 28% of the patients treated with RT, and 32% of the patients receiving RT and heat. Response has been found in previous analyses of this and other RTOG studies to be significantly related to both maximum tumor diameter (less than 3 or greater than or equal to 3 cm) and site/histology (breast/adenocarcinoma, head and neck/squamous, or other site/histologies). In the head and neck tumors less than 3 cm in diameter there was no difference in CR with irradiation alone or combined with hyperthermia (46% vs 43%). However, in the breast, and trunk and extremities a better CR rate was noted with irradiation and heat (55% and 67%) than with irradiation alone (33% and 0). In lesions less than 3 cm treated with irradiation and heat the probability of remaining in response was 80% compared with 15% with irradiation alone. In lesions larger than 3 cm no difference in CR was observed in either treatment group. It has been hypothesized that the response rate is higher in patients with smaller lesions (less than 3 cm) and in breast/chest wall, trunk/extremity lesions because these tumors and anatomical sites are easier to heat adequately. Problems encountered in correlating tumor response with quality of heating include less than optimal heating in larger lesions and the limited ability of current thermometry to accurately represent the temperature distribution in a tumor. Furthermore, differences in equipment and treatment practices among institutions add to the variability in heat administration data collected. In addition, tumor response may be difficult to judge because of short survival of some patients and occasionally rapid tumor regression that may cause necrosis which may be misinterpreted as persistent tumor.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1989

Hyperthermia quality assurance guidelines.

These Hyperthermia Quality Assurance guidelines are a result of a joint workshop of the Hyperthermia Committee of the American College of Radiology and the Hyperthermia Physics Center, which is the national quality assurance program under Contract No. N01-CM-37512 with the National Cancer Institute. Hyperthermia technology presently lacks the kind of standardization in equipment, treatment procedures, patient monitoring, and treatment documentation available in radiotherapy. Therefore, preventing unacceptable variability in treatment data demands a strong commitment to in-house quality control procedures and to centralized quality assurance reviews in cooperative multi-institutional trials. This paper presents a set of test procedures necessary to ensure proper operation of equipment, suggests a frequency for such tests, and also includes guidelines on quality control procedures to be used during treatment to improve the safety, effectiveness, and reproducibility of hyperthermia treatments. A set of forms are presented to indicate the minimum data, albeit incomplete, that must be collected for acceptable documentation of treatment. These guidelines should be valuable not only to the new entrants in the field but also to those participating in multi-institutional cooperative hyperthermia trials. They have been approved by the Hyperthermia Committees of American College of Radiology, American Society for Therapeutic Radiology and Oncology, Radiation Therapy Oncology Group and the American Association of Physicists in Medicine.

Forms and Records Control↗
PubMed1987

Relationship between the neurotoxicity of the hypoxic cell radiosensitizer SR 2508 and the pharmacokinetic profile.

Complete pharmacological data from 71 patients treated on the phase I trial of SR 2508 were analyzed to see if the dose-limiting toxicity of peripheral neuropathy is related to the individual patient's pharmacokinetic profile. In a retrospective analysis, the risk of toxicity was best predicted by using the bivariate model of total drug exposure and the time over which the treatment course was given. Drug exposure [area under the curve (AUC)] for a single treatment was calculated by the integral over time of the serum concentration of SR 2508. Since the AUC was constant during the course of a patient's treatment, the total drug exposure (total-AUC) was estimated by the product of the AUC times the number of drug administrations. While the clinical efficacy of hypoxic cell sensitizers remains to be proven, SR 2508 is better tolerated than its predecessors, misonidazole and desmethylmisonidazole, as three times the amount of SR 2508 can be given. If this model is confirmed in the current phase II and III trials, the probability of developing neuropathy would be predictable for an individual patient from measurements made at the time of the first drug dose, allowing for the adjustment of drug schedule to avoid all but minor toxicity.

Dose-Response Relationship, Drug↗
PubMed1986

Analysis of neutron radiotherapy treatment complications.

A total of 6,345 patients have been entered in the RTOG particle registry since it was opened in 1980. Three hundred thirty of those patients were treated with neutrons alone for head and neck cancers, and 128 were treated with neutrons alone for pelvic cancers. The late normal Tissue Severe Toxicity (life-threatening and fatal) rates in the head and neck were 9% for high energy accelerators and 20% for low energy accelerators. The late normal Tissue Severe Toxicity rates in the pelvis were 4% for high energy accelerators and 39% with low energy accelerators.

Fast Neutrons↗
PubMed1985

Combined modality therapy with radiotherapy, chemotherapy, and immunotherapy in limited small-cell carcinoma of the lung: a Phase III cancer and Leukemia Group B Study.

Patients with limited-stage small-cell carcinoma of the lung (SCCL) were randomly assigned to a four-drug chemotherapy program consisting of methotrexate, doxorubicin, cyclophosphamide, and CCNU (MACC) or to a regimen consisting of cyclophosphamide, CCNU, and vincristine alternated with Adriamycin (Adria Laboratories, Columbus, Ohio) and vincristine (CCV/AV). All patients received 4,500 cGy, in a split course, to the primary tumor, mediastinum, and supraclavicular lymph node drainage areas and 3,000 cGy to the whole brain. After four cycles of chemotherapy, patients were randomly assigned to chemotherapy plus methanol extractable residue of BCG (MER-BCG) or no MER-BCG. The complete response frequencies were similar for the two regimens (54% and 48%) as were the median survivals (12.0 and 11.5 months) and the two-year survival rates (15% and 17%). Immunotherapy with MER-BCG did not prolong the time to disease progression or improve survival. Women had a greater chance of achieving a complete remission independent of performance status. There was a complex interaction between sex and the chemotherapy regimens that may have important implications for the design and stratification of future trials in SCCL.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1984

Surgical staging in carcinoma of the prostate: the RTOG experience. Radiation Therapy Oncology Group.

One hundred thirty-six patients with carcinoma of the prostate entered on phase III RTOG studies (RTOG 75-06 and RTOG 77-06) between 1976 and the end of 1980 underwent staging lymphadenectomy prior to irradiation. The operative reports and histological findings have been reviewed in order to determine the patterns of intrapelvic tumor spread and to correlate the type of surgical procedure and the extent of lymphatic dissection with the incidence and type of postirradiation complications (primarily genital and lower extremity lymphedema). The surgical procedures were classified into three categories according to extent: 1) biopsy only, 2) limited (diagnostic) dissection, and 3) complete (therapeutic) dissection. The incidence of postirradiation lymphedema was found to be strongly dependent upon the extent of dissection. Patients undergoing limited (diagnostic) dissection followed by pelvic irradiation have a 25-30% risk of developing this debilitating complication. In patients undergoing complete (therapeutic) dissection followed by pelvic irradiation lymphedema has been observed in 66% of cases.

Biopsy↗
PubMed1984

Adjuvant radiation therapy for rectal cancer.

Since 1976, 104 patients with rectal cancer have been treated with a new approach of combined pre- and postoperative radiation. All patients were given 500 rad preoperative irradiation on the day of or the day before surgery. Surgery in the majority of patients was an abdominal perineal resection. The disease was then staged pathologically according to Astler-Coller's modification of Duke's staging. Patients with early stage cancer (Stages A and B1) were followed with no further therapy. Patients with poor prognostic characteristics (Stages B2, C1, C2) were given postoperative pelvic irradiation (4500 rad in 5 weeks). Twenty-nine patients were found to have Stage A or B1 cancer and were followed with no further therapy. Of these 29 patients, 1 patient developed recurrence and one has died of metastatic disease. The excellent survival of patients with early tumors indicates that minimizing the role of adjuvant therapy in this group has not been detrimental to their survival. Fifteen were found to have liver metastases at laparotomy and had just a colostomy and palliative therapy. Sixty patients had Stage B2 and C disease. Thirty-one received postoperative irradiation as per protocol. Twenty-nine patients did not receive postoperative irradiation for a variety of reasons. Follow-up ranges from 1 to 7 years in these patients. Of the 29 patients with Stage B2 and C disease who should have but did not receive postoperative radiation, 10 patients (34%) have developed a recurrence in the pelvis, and 5 other patients (17%) have developed metastatic disease. Of 31 patients who received postoperative irradiation, only 2 patients (6%) developed a local recurrence and 4 patients (13%) have developed distant metastases. Survival at 3 years was 80% for patients receiving the combined treatment, as compared to 42% for those not receiving the postoperative part of the treatment protocol.

Adenocarcinoma↗
PubMed1983

Preliminary report on phase III RTOG studies of extended-field irradiation in carcinoma of the prostate.

The radiation therapy oncology group (RTOG) has conducted two studies testing the value of extended-versus limited-fields in carcinoma of the prostate. RTOG protocol 75-06 tests the value of paraaortic irradiation in patients with locally advanced tumors limited to the pelvis. RTOG protocol 77-06 tests the value of pelvic irradiation in patients with tumors limited to the prostate. Two hundred sixty-eight evaluable patients have been entered on RTOG 75-06, and 219 on RTOG 77-06 prior to 1981. This is a preliminary report on treatment-related morbidity in patients followed for a minimum of 1 year. Treatment-related morbidity has been classified according to a five-grade severity classification schema and correlated with the protocol option assignment in order to determine whether the use of extended fields had an effect on the incidence of side effects. Thirty-one percent of 268 patients on RTOG 75-06 and 34% of 219 patients on RTOG 77-06 had some form of treatment side effects. The majority (over 80%) of these were mild (grade 1 and 2) and by definition did not interfere with the patients' performance (life style). Only three patients on RTOG 75-06 and one on RTOG 77-06 had grade 4 complications (by definition requiring a surgical intervention). No fatal (grade 5) complications have been recorded so far. The use of paraaortic fields in RTOG 75-06 and pelvic fields in RTOG 77-06 have not resulted in a significant increase of GI or GU morbidity at this time. The only statistically significant trend was the incidence of postirradiation genital and lower extremity edema which strongly correlated with the extent of staging lymphadenectomy.

Aged↗
PubMed1980

Treatment of advanced colon cancer with 5-fluorouracil (NSC19893) versus cyclophosphamide (NSC26271) plus 5-fluorouracil: prognostic aspects of the differential white blood cell count.

One hundred twenty-one patients with advanced measurable adenocarcinoma of the colon were randomized for treatment with intravenous 5-fluorouracil (IV 5-FU) alone, 15 mg/kg/week vs. cytoxan, 15 mg/kg/week IV, on day 1 and 5-FU, 15 mg/kg/week IV during weeks 2--5, repeated in a six-week cycle. Age, sex, performance status, and disease free intervals, were comparable in both arms. Response frequency was 11% for treatment with 5-FU alone and 10% for treatment with combination therapy. The median survival time was significantly greater in the 5-FU-alone arm (8.4 months vs. 5.6 months, P less than 0.05). In both arms, survival was correlated with the nadir white blood count (WBC) achieved during therapy (P less than 0.02). Fourteen patients had pretreatment WBC of greater than 12,000/mm3. None of them had fever, bone marrow involvement with tumor, or recognizable infection at study entry. The 14 patients had a median survival time of 2.3 months, significantly shorter than that of patients with normal pretreatment WBC (P less than 0.05). A pretreatment lymphocyte count was available for all patients. No association between this value and either response to chemotherapy or survival time was noted. These results support the superiority of 5-FU to the combination of 5-FU and cytoxan in the treatment of colon carcinoma, and point to the prognostic significance of the pretreatment WBC in this disease.

Adenocarcinoma↗
PubMed1977

Overview of four clinical studies of chemotherapy for stage III and IV non-Hodgkin's lymphomas by the Cancer and Leukemia Group B.

This paper presents an overview of four Cancer and Leukemia Group B studies in 1266 patients with stage III-IV non-Hodgkin's lymphoma. The cases were analyzed across protocols; the major prognostic determinants were prior chemotherapy, age, and histology. The four studies proved that cyclophosphamide maintenance was superior to no maintenance even after prolonged intensive induction chemotherapy. Furthermore, the reinforcement program of monthly pulse doses of vincristine and prednisone, whose value was established in the treatment of acute leukemia, led to highly significant improvement in remission duration and survival. Other facets of the chemotherapy programs are still being subjected to analysis, but this report sets out some preliminary conclusions.

Adult↗
PubMed1976

Bleomycin (NSC-125066) therapy of responsive solid tumors.

110 patients with far advanced head and neck squamous or testicular carcinoma were treated with bleomycin given by intravenous (i.v.) or intramuscular (i.m.) injection according to a randomized assignment. While responses were observed more frequently in patients treated by the intramuscular route, no superiority can be attributed clearly to intramuscular therapy. Responses were seen in 6.2% of head and neck squamous carcinoma patients (5/81; i.m. 3/38, 8%; i.v. 2/41, 5%) while 14% of testicular tumors responded (4/29; i.m. 4/13, 29%; i.v. 0/16, 0%). Toxicity was, in general, manageable.

Age Factors↗