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D S Lamb

Publications and source records attributed to D S Lamb.

29 records · Page 2Linked to original sources
PubMed1992

Treatment and planning decisions in non-small cell carcinoma of the lung: an Australasian patterns of practice study.

Fourteen practising radiation oncologists were surveyed to assess their treatment and planning habits utilizing six sample cases of non-small cell carcinoma of the lung. Respondents were first given a general questionnaire, designed to evaluate their theoretical treatment and planning recommendations based on various tumour and patient related variables. Respondents then undertook a practical planning exercise utilizing planning CT and simulator radiographs for each of the six sample cases. Each case was accompanied by a brief history and report outlining specific tumour stage and non-stage related variables. The practical planning exercise was repeated on the second day of the survey utilizing different non-stage related variables but identical radiology and stage-related information. This design enabled firstly, a comparison of clinicians' intended policy and planning methods with actual policy and planning decisions, and secondly, an assessment of intra-clinician variability in decision making and planning practice. Good agreement was evident among clinicians with respect to general, non-case specific treatment policies; however, very significant variation occurred at an inter- and intra-clinician level and involved the entire treatment and planning process for individual cases. Despite identical treatment intent across identical radiological case pairings, clinicians chose widely differing margins and target volumes in their planning exercise. Treatment intent appeared to be influenced more by non-stage related variables rather than stage related information and radiological appearances per se. We have shown that experienced radiation oncologists do not adhere to stated case selection criteria and show inconsistencies in their treatment planning for non-small cell carcinoma of the lung.

Australia↗
PubMed1991

Prostate irradiation does not affect the serum prostatic acid phosphatase level.

Twenty-nine consecutive patients with localized prostatic carcinoma were studied prospectively to assess the effect of radical pelvic irradiation on the serum prostatic acid phosphatase level (SPAPL). The doses of radiation given ranged from 64.00 to 66.00 Gy. SPAPLs were taken before, during and shortly after their treatment. No significant individual variations in SPAPLs were found. When patients with prostatic carcinoma show rises in serum prostatic acid phosphatase during or after pelvic irradiation, these are unlikely to be due to their treatment and occult pelvic nodal or bony disease should be considered.

Acid Phosphatase↗
PubMed1991

Blindness in patients after external beam irradiation for pituitary adenomas: two cases occurring after small daily fractional doses.

We report two cases of blindness occurring within 10 months of completion of radiation with 45 Gy in 1.80 Gy fractions given five times weekly. The literature on blindness as a complication of pituitary irradiation is reviewed. There have been no reported cases of total visual loss occurring as a consequence of treatment with fractional doses of less than 2 Gy. Visual loss due to radiation damage usually occurs within two years of completion of treatment in contrast to visual loss due to recurrence or empty sella syndrome, which usually occur more than two years after the completion of therapy. Other causes of blindness not related to the radiation, and potentially reversible, must be considered. However, these causes usually have a distinctively different clinical picture. Fraction size, total dose, and treatment time are all important factors when considering the biological effects of radiation to the pituitary region.

Adenoma↗
PubMed1990

Results of treatment of cancer of the cervix in Wellington 1980-4.

A review was undertaken of all 115 women with invasive carcinoma of the cervix referred for treatment to the Wellington regional centre during the period 1980-4. In comparison with the previous five year period, there were 31 (37%) more patients, and a higher proportion of patients had stage I and II disease. The incidence of disease was significantly greater in Maori compared with nonMaori. Treatment was by various combinations of surgery and radiation according to agreed protocols. The actuarial survival at five years was 73% for the whole group, 89% for 64 stage I patients, 65% for 28 stage II patients and 45% for 19 stage III patients. The actuarial risk of a major treatment complication within the first five years was 8.8%. These results confirm that regional centres in New Zealand employing a multidisciplinary approach to patient assessment and treatment can achieve high cure rates with an acceptable incidence of treatment complications. However, prevention of the disease by effective cervical screening programmes should remain an objective of health services in New Zealand.

Adult↗
PubMed1990

Accelerated fractionation radiotherapy for advanced head and neck cancer.

Between 1981 and 1986, 89 patients with advanced head and neck squamous cancer were treated with a continuous accelerated fractionation radiotherapy (AFRT) regimen. Three fractions of 1.80 Gy, 4 h apart, were given on three treatment days per week (Monday, Wednesday, Friday), and the tumour dose was taken to 59.40 Gy in 33 fractions in 24-25 days. Acute mucosal reactions were generally quite severe, but a split was avoided by providing the patient with intensive support, often as an in-patient, until the reactions settled. Late radiation effects have been comparable to those obtained with conventional fractionation. The probability of local-regional control was 47% at 3 years for 69 previously untreated patients, whereas it was only 12% at one year for 20 patients treated for recurrence after radical surgery. Fifty-eight previously untreated patients with tumours arising in the upper aero-digestive tract were analysed in greater detail. The probability of local-regional control at 3 years was 78% for 17 Stage III patients and 15% for 31 Stage IV patients. This schedule of continuous AFRT is feasible and merits further investigation.

Carcinoma, Squamous Cell↗
PubMed1990

Arteriovenous malformations of the brain: outcome of conventional radiotherapy in the management of 33 cases.

Thirty three patients with inoperable arteriovenous malformations of the brain received conventionally fractionated megavoltage photon radiotherapy. The dose varied between 30.00 wand 50.00 Gy with a median of 40.00 Gy. Treatment was not associated with any significant morbidity. Follow-up ranged from 16 months to 148 months, with a median of 79 months. The projected 5-year survival is 92% and rebleed-free survival 78%. There was a trend of increased bleed-free survival for doses greater than 46.00 Gy.

Adolescent↗
PubMed1989

Localized grade I non-Hodgkin's lymphoma: results of treatment with radiotherapy alone in 88 patients.

Eighty-eight patients entered into the British National Lymphoma Investigation with clinical stage I and II, grade I non-Hodgkin's lymphoma were treated initially with involved field radiotherapy alone. Eighty-one per cent presented with nodal disease. The duration of follow-up was 25-116 months, with a median of 54 months. Fifteen patients died of disease and the 5-year survival of the whole group was 83%. The complete response rate was dependent on the radiotherapy dose and was greater than 90% for doses of 3500 cGy and over. Most failures occurred at distant rather than adjacent sites, suggesting that extended field radiotherapy would not have affected the outcome. Second-line treatment induced complete remission in 66% of patients who relapsed. The prognosis was significantly worse in patients with intra-abdominal disease.

Adult↗
PubMed1984

Localised grade 2 non-Hodgkin's lymphoma: results of treatment with radiotherapy (BNLI Report No. 24).

This report reviews 85 patients entered into the British National Lymphoma Investigation with localised (clinical Stage 1 and 2) Grade 2 non-Hodgkin's lymphoma, who were treated initially with radiotherapy alone. Almost half of all patients presented with extranodal disease. The duration of follow-up was 20-106 months. There were 33 deaths due to non-Hodgkin's lymphoma. The complete local response rate was dependent on the radiotherapy dose and reached 100% for doses of 4500 cGy or more. Most first failures occurred at a distant nodal site or were due to the development of generalised disease. There was a significant difference in actuarial survival between Stage 1 and Stage 2 patients (P less than 0.005). The 5-year survivals were 78% and 40%, respectively. The site of presenting disease was also important. Stage 1 patients with nodal or ear, nose and throat (ENT) disease had an excellent 5-year survival of 84%, but Stage 2 patients with nodal or ENT disease had a 5-year survival of only 46%. As many of these Stage 2 patients rapidly developed disseminated disease, their survival might have been improved by treatment with chemotherapy before radiotherapy.

Adult↗