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Biomedical subjects

G M Thomas

Publications and source records attributed to G M Thomas.

At least 73 records · Page 4Linked to original sources

Outcome of patients with unfavorable optimally cytoreduced ovarian cancer treated with chemotherapy and whole abdominal radiation.

There is a subgroup of patients with Stage II or III ovarian cancer whose survival is poor despite optimal cytoreduction of tumor and abdominopelvic radiation. This study examined whether the survival of these patients, who have tumor with unfavorable histopathological characteristics and/or small residual disease, could be improved by giving chemotherapy before radiation. Forty-four out of fifty-one eligible patients, seen between 1981 and 1985, with Stage II or III disease were entered into the study. Following six courses of cisplatin-based chemotherapy, 33 (75%) received abdominopelvic radiotherapy. Survival was compared to that of 48 eligible matched control patients, treated with radiation between 1978 and 1981. The median follow-up is 6.6 years. The median survival was extended from 2.4 to 5.7 years (P = 0.13), and 42.6% of patients receiving combined therapy were free of relapse at 5 years, compared to 21.6% (P = 0.03) in the historical control group, treated with abdominopelvic irradiation alone. Only 2 of 44 patients in the combined group required surgery for bowel obstruction, as did 1 of 48 in the control group. Tolerance and toxicity of the combined approach were acceptable. Although we cannot be certain that the entire benefit we observed was not attributable to the chemotherapy alone, there is evidence that the radiotherapy may have been additive. Chemotherapy followed by abdominopelvic radiotherapy seems a reasonable management policy in these patients.

Antineoplastic Combined Chemotherapy Protocols↗

An assessment of combined tumour markers in patients with seminoma: placental alkaline phosphatase (PLAP), lactate dehydrogenase (LD) and beta human chorionic gonadotrophin (beta HCG).

We have assessed the tumour markers placental alkaline phosphatase (PLAP), lactate dehydrogenase (LD), and human chorionic gonadotrophin (beta HCG) using 2,000 serum samples from 286 patients with seminoma. The ROC curves show that no one marker performs adequately for the detection of disease either at initial staging or during follow-up. We used a Markov model heuristically to devise strategies, in which marker results were assessed in combination, which might be useful in clinical practice. We found that the best strategy was to consider a test result abnormal only if either the beta HCG was greater than 6 Ul-1 or the LD was greater than 400 U l-1 and the PLAP level was greater than 60 U l-1. This will detect about 50% of patients with disease and the false-positive rate is 2%. In practical terms this means that PLAP need only be estimated in patients whose beta HCG is less than 6 IU l-1 and whose LD is greater than 400 U l-1.

Alkaline Phosphatase↗

Radiation-induced cerebral aneurysms.

The association between vasculopathy and radiation is well recognized. Generalized arterial disruption and subsequent stenosis and occlusion is most often described. Additional vascular phenomenon, such as pseudoaneurysm formation, aneurysmal dilatation and aneurysmal rupture, are less common. We document a case of a cerebral aneurysm formation and rupture in the field radiated for cerebral neoplasm.

Astrocytoma↗

Is placental alkaline phosphatase (PLAP) a useful marker for seminoma?

The usefulness of placental alkaline phosphatase (PLAP) as a tumour marker was assessed in 1578 serum samples from 236 patients with seminoma. Smoking habits were known for all but 7 patients (22 samples). Smoking was associated with significantly higher mean levels of PLAP in disease-free patients (28.8 [S.E. 2.1] U/l vs. 15.9 [1.3] U/l in non-smokers). Mean PLAP levels were higher in patients with active disease (78.6 [23.5] U/l in non-smokers and 47.2 [18.5] U/l in smokers). The median values showed a similar trend. However, there was considerable overlap between the various groups and differences between mean and median values indicated that PLAP values were distributed asymmetrically. The predictive value of PLAP as a tumour marker was consequently much less than superficial inspection of these values might suggest. In 97 patients on surveillance, only 2 out of 11 patients who relapsed had elevated PLAP at the time of clinically detectable relapse. With the upper limit of normal PLAP quoted by our laboratory (35 U/l), specificity and sensitivity were, respectively, 88% and 45% (all patients) and 96% and 47% (non-smokers). The sensitivity and specificity of PLAP were assessed in more detail for a series of threshold values (normal vs. abnormal) with a graphical method. Only in non-smokers did PLAP seem useful and even in this group the positive predictive value of an "abnormal" test may be low; less than 50% in clinically relevant circumstances. Serum PLAP assay cannot usefully stand alone as a marker for seminoma and its routine estimation contributes little to follow-up.

Adult↗

Public health nurse salaries: associations with nurse, agency, and community characteristics.

This study applied an economic framework to the analysis of public health nurse (PHN) salaries, assessing their relationships to nurse qualifications, agency resources, community economic base, and area competition for the nurse supply. Data were obtained through interviews with 125 Ohio health departments and from various state and local reports. Associations between salaries and explanatory variables were analyzed through correlations and stepwise regression models. The PHN salaries were significantly lower and more compressed than salaries for nurses in area hospitals. Agency and community characteristics were more important than nurse education and experience in explaining salary variations. Maximum PHN salary attainable was significantly related to level of health department funding and community unemployment rate. Health departments in rural locations paid lower salaries at both minimum and maximum levels. Evidence suggested the presence of entry-level wage competition by health departments with both area hospitals and other community nursing agencies. Each 1% increase in minimum hospital nurse salaries was linked to a 0.66% increase in PHN salaries. Findings support the need to improve competitive positions of health departments as nurse shortages intensify.

Community Health Services↗

A study of post-orchiectomy surveillance in stage I testicular seminoma.

A study of post-orchiectomy surveillance without radiation therapy was done in patients with histologically pure seminoma apparently confined to the testicle. Criteria for study entry included a negative physical examination, chest x-ray, bipedal lymphogram, excretory urogram, abdomino-pelvic computerized tomography scan and serum alpha-fetoprotein. Followup consisted of frequent clinical examination, repeat lymphograms, abdominal computerized tomography scans, chest x-rays and serum markers. The purpose of this study was to determine the percentage of patients cured by orchiectomy alone, percentage who ultimately required therapy for occult metastases beyond the testicle, sites of relapse, factors predictive of relapse, and over-all cure rate and treatment morbidity. Of 81 patients followed for 3 to 43 months (median 19 months) only 3 had relapse at 3, 5 and 18 months after orchiectomy with nonbulky retroperitoneal disease: 1 patient had disease 17 months after salvage infradiaphragmatic radiation therapy, 1 had an increase in beta-human chorionic gonadotropin 11 months after radiation therapy, presumably due to occult nonseminoma, and he is receiving chemotherapy, and 1 has not yet completed treatment. Further followup is necessary to determine ultimate survival, since a risk for later relapse exists. However, to date it does not appear as if the outcome has been compromised when surveillance was applied in place of routine adjuvant radiotherapy.

Combined Modality Therapy↗

Radical radiotherapy for muscle invasive transitional cell carcinoma of the bladder: failure analysis.

Patients with muscle invasive carcinoma of the bladder treated with radical radiation were prospectively documented and followed in an attempt to identify prognostic factors predictive of the response to treatment. Data on 121 consecutive patients treated with radical radiation between 1981 and 1985 are presented. Over-all actuarial survival of the patient population (median age 70 years) was 31.6% at 5 years and cause-specific survival was 44.8%. At analysis 33 of 121 patients (27.3%) were alive with preserved bladder function. Independent prognostic factors for cause-specific survival and for complete response with radical radiation were tumor configuration, hemoglobin level and clinical stage. The rate free of local relapse was significantly influenced by stage and presence of coexistent carcinoma in situ. The study suggests that factors other than stage and grade influence prognosis in invasive bladder cancer and should be considered in interpreting treatment results.

Adult↗

Retroperitoneal lymphadenectomy for testis tumor with nerve sparing for ejaculation.

The principal morbidity of retroperitoneal lymphadenectomy is the potential loss of ejaculation and, therefore, fertility owing to damage of the retroperitoneal sympathetic nerves that form the superior hypogastric plexus. We describe the results of our retroperitoneal lymphadenectomy when individual nerves from the sympathetic ganglia are identified and preserved while still performing a thorough bilateral retroperitoneal lymphadenectomy. The nerve-sparing procedure was technically feasible in 20 of 30 consecutive patients and it was only impractical with extensive gross disease. Of the 20 patients 18 (90 per cent) ejaculate, including 8 with bulky (5 cm. or more) residual retroperitoneal disease who underwent a successful nerve-sparing operation. All 12 patients (100 per cent) with nonbulky disease ejaculate. With short followup, no retroperitoneal recurrences have been detected. This technique is an alternative to limited dissection designed to spare nerves using boundaries based on the patterns of metastatic involvement.

Ejaculation↗

Concurrent radiation and chemotherapy for carcinoma of the cervix recurrent after radical surgery.

Results of salvage therapy in patients with carcinoma of the cervix, recurrent after primary surgery, have been dismal even when disease was apparently confined to the pelvis. Further surgery or radiation therapy cured only some with central pelvic disease alone who had recurred at intervals longer than 6 months after primary therapy. To try to improve the results of salvage therapy, we used a combination of concurrent chemotherapy, 5-Fluorouracil with or without Mitomycin-C, and radiation therapy. Seventeen patients were treated. Recurrent disease was present in the pelvis or pelvis and paraaortic nodes after radical surgery for Stage IB carcinoma of the cervix. Eight of seventeen (47%) are alive, disease-free, 21 to 58 months after therapy. Seven of the eight had biopsy proven recurrence. Five of eight had recurred within 9 months of primary surgery and 7/8 had a component of pelvic side wall disease. Thus the survivors had unfavorable prognostic features. Nevertheless, the use of concurrent radiation and chemotherapy produced an exceptionally high proportion of sustained complete remissions and possible cures.

Combined Modality Therapy↗

Current therapy for dysgerminoma of the ovary.

It is important that therapy of ovarian dysgerminoma be optimized because of the young age of women affected and the threat that therapy may pose to fertility. Our understanding of dysgerminoma has improved, so that treatment schemes with better therapeutic ratio may now be used. Approximately 65% of patients present with stage IA disease. For those wishing to preserve fertility, conservative surgery with close clinical, radiologic, and serologic follow-up is the treatment of choice, with chemotherapy for relapse. Cure rates should approach 100%, and fertility is usually preserved. Intra-abdominal relapse in those not wishing to preserve fertility should be treated with modest-dose pelvic and abdominal irradiation. For those patients with disease presenting in stages IB, II, and III who wish to maintain fertility, unilateral oophorectomy followed by combination chemotherapy may be curative and spare ovarian function. Otherwise, complete surgery, followed by abdominopelvic radiation therapy, is recommended. This treatment produces less morbidity than chemotherapy and will cure approximately two-thirds of patients. Chemotherapy should be used for salvage of subsequent relapse. Both radiation and chemotherapy are highly effective treatment modalities for dysgerminoma. This information, coupled with better understanding of the patterns of disease spread and improved ability to identify nondysgerminomatous elements using serum tumor markers, means that a more conservative approach can be taken to management without compromising the chance of cure. Cure rates for dysgerminoma should now approach the role of 97% achieved in the comparable tumor, testicular seminoma.

Combined Modality Therapy↗

Controversies in the management of testicular seminoma.

The 5-year cause specific actuarial survival rate for 178 patients treated for testicular seminoma at The Princess Margaret Hospital 1977 to 1981 is 97%. Controversies exist over how to optimally use and integrate chemotherapy (CT) and radiation therapy (RT) to minimize morbidity and achieve these high cure rates. These are as follows: "surveillance only" for Stage I, the necessity of prophylactic mediastinal RT (PMI) for Stage IIA, initial RT versus CT for Stage IIB, optimal therapy for Stages III and IV, and the significance of elevated serum tumour markers. In Stage I, relapse after abdominopelvic RT (2500 cGy in 20 fractions) occurred in 2 of 150 patients (1.3%). Without routine RT relapse rates are unknown. Only 1/370 Stage IIA patients in the literature treated with infradiaphragmatic RT without PMI developed uncontrolled mediastinal disease. Prophylactic mediastinal RT confers a possible survival benefit of only 0.2% and cannot be recommended. Stage IIB is rare (only 4% of 178 patients). Initial CT produces complete responses in approximately 80% of patients, but its curative potential is unknown therefore consolidation RT or surgery is often given. Initial subdiaphragmatic RT followed by CT for relapse cures at least 85% of patients (5/5 marker negative) and spares 50% of unnecessary CT. Sequential therapy minimizes potential treatment morbidity without compromising cure. Initial CT is recommended for Stages III and IV. The literature survival after RT is only 36% (136/375). The role of consolidation RT is unknown. Optimal management of seminoma implies integration of RT and CT to decrease morbidity and still maintain high cure rates.

Antineoplastic Combined Chemotherapy Protocols↗

Systemic pseudallescheriasis in a patient with acute myelocytic leukemia.

Presented is a case of widely disseminated systemic pseudallescheriasis in a 41 year old male with acute myelocytic leukemia. The immediate cause of death appeared to be due to an extensive invasion of the lungs which showed massive intra-alveolar hemorrhages, congestion, mycotic thrombi, and multiple fungal lesions in all lobes. Pseudallescheria boydii was diagnosed histopathologically by virtue of its characteristic conidia present in miliary lesions throughout a wide range of host's tissues, including the brain and the thyroid. Three antemortem blood specimens cultured during the patient's final hospital stay were positive for the fungus. It was concluded the fungemia was responsible for the rapid and widespread dispersion of P. boydii in this debilitated patient who was granulocytopenic and immunosuppressed.

Adult↗

Postoperative local abdominal irradiation for cancer of the colon above the peritoneal reflection.

A retrospective analysis of 82 patients with cancer of the colon above the peritoneal reflection who received postoperative local abdominal irradiation was undertaken to assess the survival, patterns of failure, and toxicity of treatment. Forty-eight patients (adjuvant group) had a complete resection, but were felt to be at high risk for local relapse and received postoperative local abdominal irradiation. Thirty-four patients had gross residual disease following surgery. The 5-year actuarial survival and local relapse free survival were 67 and 67%, respectively, in the adjuvant group. In this group, local relapse was observed in 9 of 28 patients with Stage C disease in contrast to 3 of 20 patients with Stage B2 disease; 1 of 14 patients with lesions in the right colon failed locally compared to 11 of 35 patients with lesions in the left. Only 2 of the 34 patients with gross residual disease remained relapse free from 93% of patients having a component of local failure. The majority of the treatment morbidity was seen in patients with gross residual disease. Prospective randomized studies should be done to determine the efficacy of postoperative irradiation in patients with colon carcinoma who are at high risk for local recurrence following surgical resection.

Abdomen↗

Total abdominal irradiation for cancer of the colon.

A retrospective analysis of 55 patients treated with whole abdominal irradiation following surgical excision for cancer of the colon is presented. Three groups of patients were given whole abdominal irradiation, eight with gross residual tumor following surgery, 17 with peritoneal seeding, and 30 who had complete surgical excision of the tumor but were felt to be at high risk for relapse. Only one of the eight patients with gross residual tumor, and one of the 17 with peritoneal metastases, are currently alive and well, with the majority dying from local or peritoneal metastases. The 5 year actuarial survival for the 30 patients irradiated following complete surgical excision is 55%. The treatment was well tolerated and few complications were observed. It is concluded that whole abdominal irradiation is ineffective for the treatment of colon cancer if peritoneal metastases are present, or if gross residual tumor is left behind following surgery. A randomized controlled clinical trial is being organized to test whether total abdominal irradiation is of benefit in terms of survival in high risk colon cancer patients following complete surgical removal.

Adenocarcinoma↗

Bovine anaplasmosis: elimination of the carrier state with injectable long-acting oxytetracycline.

Long-acting oxytetracycline was administered intramuscularly (20 mg/kg) at 3-day intervals to each of 16 naturally infected Anaplasma marginale carrier beef cows; 8 of the 16 cows were given 3 injections and the other 8 cows were given 4 injections. Four cows seropositive for A marginale served as untreated controls. Rapid card agglutination and complement fixation tests were performed 5 times during the 130-day posttreatment period. All treated cows became negative to both serologic procedures, whereas control cows remained seropositive. Three splenectomized calves that received pooled blood from the treated cows, 120 days following treatment, remained free of anaplasmosis for 60 days following inoculation. One splenectomized calf that received blood from the control cows developed anaplasmosis. It was concluded that long-acting oxytetracycline can be used to eliminate the naturally acquired carrier state of anaplasmosis in cattle.

Anaplasmosis↗