Limited Field Irradiation Research Articles

Treatment of traumatic radioulnar synostosis by excision and postoperative low-dose irradiation

Post-traumatic radioulnar synostosis can have a profound effect on upper extremity function. Prior reports of excision, with and without interposition material, have demonstrated frequent recurrence and disappointing results. Based on a favorable experience with radiation prophylaxis of heterotopic ossification following total hip arthroplasty, this modality has been used in the management of post-traumatic forearm synostosis. Four cases using excision of bony synostosis followed by single-fraction, low-dose (800 cGy), limited-field irradiation are presented. With a follow-up period of 1–4 years after excision and irradiation, all four patients had total arcs of forearm rotation between 115° and 120°. Each patient noted sustained functional improvement, and there was no x-ray film evidence of recurrent synostosis formation. Single fraction irradiation did not require ongoing patient compliance nor did it complicate rehabilitative efforts. Furthermore, soft tissue and bony healing were not impaired.

Third-body irradiation as an effective palliative treatment for painful multiple bone metastases resistant to chemo- or hormonal treatment

Fifty-three patients had 54 third-body areas irradiated for breast and prostate bone metastases using the third-body irradiation technique during a period of 6 years. These patients were previously treated with chemotherapy, hormonal therapy and limited field irradiation. Seventy percent responded completely and 24% partially. This modality is safe and effective for pain relief.

The christie hospital breast conservation trial: An update at 8 years from inception

In 1990, we published the results of a clinical trial involving 708 patients with breast carcinoma of 4 cm or less in diameter, who, following lumpectomy, were randomized to have radiotherapy to the tumour bed only (limited field, LF group) or to the whole breast and regional nodes (wide field, WF group). No adjuvant systemic therapy was prescribed. At the time the median follow-up was 37 months. We present the updated results after an extended median follow-up of 65 months. The overall survival is 72.7% and 71.2% for the LF and WF groups respectively. The actuarial breast recurrence rate (first event) is 15% (LF) versus 11% (WF) for infiltrating ductal carcinoma, whereas, for infiltrating lobular carcinoma, the recurrence rate was 34% (LF) versus 8% (WF). A high actual recurrence rate of 21% (LF) and 14% (WF) was also found for extensive ductal carcinoma in situ. It was extremely rare for medullary, mucoid or tubular carcinomas to recur. Salvage surgery was possible in 86% (LF) and 90% (WF) respectively. The recurrence rate in the breast following lumpectomy and wide field irradiation is comparable with others reported in the literature. This trial also shows the lumpectomy with limited field irradiation is feasible, albeit with a higher breast recurrence rate; the latter could be reduced by improved selection and refinement of the technique.

Radiation treatment planning for malignant astrocytomas

Treatment planning for malignant astrocytomas has been an area of controversy for the past 30 years. Several key studies have supported widely divergent treatment philosophies. Before the availability of computerized tomography (CT) scanning, whole brain irradiation (WBRT) was necessary to ensure adequate tumor coverage, due to limitations of less-sophisticated imaging studies. Following the introduction of high-quality CT scanning and magnetic resonance imaging (MRI), there was a shift to the use of more-limited radiation fields to treat only the contrast-enhancing tumor plus a margin. Additional impetus for use of smaller treatment fields came from studies implicating WBRT in cerebral dysfunction in long-term survivors.‘~* Recently, the appeal of limited field irradiation has been tempered by biopsy and autopsy studies that suggest wider migration of malignant cells than previously believed?” There have thus emerged two schools of thought. One is that patients should receive limited field irradiation, with the hope of avoiding mental deterioration in the few long-term survivors. The opposite argument is that patients should receive WBRT in order to treat all potential sites of tumor infiltration in all patients. While both points of view have merit, they must be reconciled with the fact that many patients will die of their disease within 1 year of diagnosis, regardless of the radiation fields used. The bulk of retrospective data available do not show a survival advantage to large versus small field irradiation (for review, see reference 5). The first study to systematically analyze radiation planning for high-grade astrocytomas was published by Concannon et al” in 1960. Partial brain irradiation (PBRT) fields were compared with tumor volumes identified at autopsy in 2 1 patients who died shortly after starting treatment. The fields were designed

Poorly differentiated gliomas of the cerebellum. A study of 18 patients

Eighteen patients with poorly differentiated gliomas of the cerebellum were treated by the University of California San Francisco Neuro-Oncology Service between January 1977 and January 1987. Within this group pathologic diagnosis included five glioblastoma multiforme (28%), nine anaplastic astrocytomas (50%), and four mixed malignant gliomas (22%). The group included 13 male and five female patients with a median age at diagnosis of 23 years (range, 4-46 years). All patients underwent surgical resection, 16 of 18 received radiation therapy (12 limited-field irradiation and four whole-brain with or without a posterior fossa boost), and 16 of 18 received chemotherapy. Overall median survival was 31.5 months (range, 5-366 months). Ten patients (55%) died of recurrent disease with a median survival of 32 months (range, 5-128 months), two of whom manifested metastatic disease within the central nervous system (one parietal lobe and one cervical cord). Of the two extracerebellar metastatic recurrences, one patient failed at the junction of whole-brain irradiation and the cervical cord and one patient failed after inadequate posterior fossa irradiation. Eight patients (45%) are alive with a median follow-up of 27.5 months (range, 14-366 months). In this series recurrences of primary cerebellar anaplastic gliomas were locoregional failures. As a consequence, the authors suggest high-dose limited-field irradiation directed at the primary tumor as in their current strategy utilized for supratentorial gliomas.

Treatment results of brain germinoma: limited field irradiation vs. entire cns irradiation

Treatment results of brain germinoma: limited field irradiation vs. entire cns irradiation

Prostatic carcinoma: limited field irradiation.

This is a retrospective study of 251 patients with histologically proven adenocarcinoma treated primarily with limited field radiotherapy techniques, under the principle direction of authors JMV and JPG, between 1968 and 1981 in San Francisco, California. All patients are followed for a minimum of 3 years; mean follow-up is 7.3 years. Routine clinical staging procedures included: H&P, digital prostate exam, cystoscopy, biopsy, blood studies including serum acid phosphatase, and imaging studies including chest X ray, IVP, bone survey or radionucleotide bone scan, and in recent years, pelvic CT scans. Twelve patients are Stage A1, 37-Stage A2, 50-Stage B, 140-Stage C1 and 12-Stage C2. Ninety percent of all cases and 85% of Stage C patients were treated with limited fields to the prostate and periprostatic volume only. Total doses were prescribed at midplane or isocenter and were generally 6500-7000 cGy, daily doses of 180-200 cGy, 5 days per week. Actuarial 5- and 10-year survival rates are: entire population-69% and 47%; Stage A1-74% and 50%; Stage A2-81% and 67%; Stage B-84% and 53%; Stage C1-63% and 42%; Stage C2-32% and 11%. The 5- and 10-year disease-free actuarial survivals are: entire population-71% and 50%; Stage A1-89% and 74%; Stage A2-82% and 69%; Stage B-71% and 52%; Stage C1-67% and 44%; Stage C2-0%. Sites of recurrence, alone or as a component of the failure pattern are: 37 (15%) local, 11 (4%) symptomatic regional recurrence (lower extremity edema, pelvic pain/sciatica, hydroureteronephrosis), and 87 (35%) distant metastasis. Seven (3%) had unknown sites of failure. Local-regional failure occurred in 42% of Stage C2 patients. Concomitant hormonal therapy has no survival impact on Stage C1 patients and poorly differentiated histology is associated with decreased determinate and disease-free survival rate of 5 years. Complications correlate with treatment technique, being more frequent with single field per day treatment plans. In patients treated with multiple fields per day or rotational plans, complications occur in less than 8% of patients and major complications have not occurred.

Lymphocyte predominant Hodgkin's disease: Clinical presentation and results of treatment

The records of 59 patients with lymphocyte predominant Hodgkin's disease (LPHD) evaluated and treated at Stanford University Medical Center between 1963 and 1983 were reviewed. Of these 59 patients, 92% are alive at 10 years following treatment, 78% are relapse-free, and none have died of Hodgkin's disease. Compared with the other histologic subtypes of Hodgkin's disease, LPHD presents more frequently as stage I or II disease (78% vs. 55%) and less frequently with constitutional symptoms (7% vs. 32%). Despite these factors, there is no statistically significant difference in either survival or freedom-from-relapse (FFR) between the histologic subtypes when comparisons are made on a stage-for-stage basis. Analysis of sites of presentation and relapse reveals that LPHD rarely involves intrathoracic structures. Patients with C.S. I disease presenting in inguinofemoral or high cervical lymph nodes do not require staging laparotomy as none of these patients were upstaged by surgery. Patients with stage I disease involving high cervical lymph nodes may be treated with limited field irradiation employing fields no more extensive than a mantle and Waldeyer's ring field, as no relapses have been seen in such patients treated in this fashion. Although limited field irradiation was used successfully for LPHD presenting in other localized sites, inadequate patient numbers preclude assessment of this treatment for those clinical presentations.

Management of Hodgkin's disease in children and adolescents.

Between 1970 and 1980, 66 children or adolescents with Hodgkin's disease were treated at the Children's Hospital of Philadelphia. Since 1977, prepubertal patients and postpubertal patients with Stage IIA massive mediastinal disease or Stage IIB-IVB disease were clinically staged and treated with six courses of chemotherapy and 2000 rad involved-field irradiation. Postpubertal patients with Stage IA or IIA disease were staged pathologically and treated with 3600-4400 rad extended-field irradiation. At four years, actuarial survival in 27 patients with Stage IA or IIA disease is 100%; relapse-free survival is 86% in 16 patients treated with combined modality and 70% in 11 patients treated with irradiation. Among 39 patients with Stage IIB-IVB disease, 34 received combined modality; at five years, survival is 86% and relapse-free survival is 60%. In the majority of cases relapses in patients treated with combined modality could be better explained by chemotherapy failure rather than by insufficient radiation. Clinical staging and combined modality therapy may offer advantages for prepubertal patients and those postpubertal patients at high risk of relapse when treated with irradiation alone. The complications of laparotomy and splenectomy are avoided; however, with 2000 rad and limited-field irradiation, hypothyroidism does occur and growth disturbances may appear.

Patterns of relapse in stages I, II and IIIA Hodgkin's disease: Influence of initial therapy and implications for the future

An analysis was undertaken of the patterns of relapse observed among 111 patients with Stages I–IIIA Hodgkin's disease. All had undergone staging laparotomy and then received either extended field irradiation alone (60%) or limited field irradiation followed by MOPP (nitrogen mustard, vincristine, procarbazine and prednisone) chemotherapy. A total of 26 relapses occurred; relapse rates after irradiation alone were 34% but only 7% following irradiation plus adjuvant chemotherapy. The duration of both remission and survival was significantly longer for the patients receiving irradiation plus chemotherapy than for those treated with irradiation alone ( p = < 0.001, <0.05, respectively). Survival differences in this study should be considered preliminary, however, until several more years of patient follow-up accrues. For patients with “E” stage disease, remission duration and survival were significantly impaired after irradiation alone; this poor prognosis was not observed after therapy with irradiation plus MOPP. The most common sites of relapse for all patients were marginal recurrences (54%) within mediastinal nodes or adjacent lung parenchyma. Extranodal extension to the lung and large mediastinal masses were significant predisposing factors; 86% of these relapses followed therapy with irradiation alone. Among Stage IIIA patients treated with irradiation alone, abdominal lymph node involvement was associated with more relapses (50%) than if disease was confined to spleen and splenic hilar lymph nodes (17%). No relapses occurred in Stage IIIA disease after adjuvant chemotherapy. Certain patterns of clinical presentation appear most likely to benefit from combined modality therapy. These include “E” stage disease of the lung, large mediastinal masses and Stage IIIA patients with involvement of abdominal lymph nodes.

Limited extranodal Hodgkin's disease: Unfavorable prognosis and therapeutic implications

The Ann Arbor Conference on the staging of Hodgkin's disease suggested that the prognosis in patients with “E” stage Hodgkin's disease is similar to that in comparable patients with only nodal disease. A comparative analysis was undertaken of 84 patients with pathologically staged IIA to IIIA disease and 18 patients with stage II EA to III EA disease. The lung was the principal site of extranodal extension (15 patients). Both groups were treated concurrently with either extended field irradiation alone or limited field irradiation followed by MOPP chemotherapy (nitrogen mustard, vincristine, procarbazine and prednisone). Relapse rates after irradiation alone were 29 per cent for the patients with stage HA to IIIA disease and 82 per cent for the patients with “E” stage disease. Patients who received adjuvant chemotherapy had relapse rates of 6 per cent and 14 per cent, respectively. Most “E” stage relapses were regional recurrences within the lung parenchyma. Wilcoxon analysis revealed a significantly shorter remission duration and survival for the patients with “E” stage disease after irradiation alone, but there were no differences between the two patient populations treated with irradiation followed by chemotherapy. These data indicate that the prognosis in patients with “E” stage Hodgkin's disease of the lung is poor when they are treated with irradiation alone, and that adjuvant chemotherapy should be considered for such patients.

The therapeutic implications of splenic involvement in stage IIIA Hodgkin's disease

In an effort to determine the most appropriate initial therapy for patients with stage IIIA Hodgkin's disease, a comparative analysis was undertaken of 13 pathologically staged IIIA Hodgkin's disease patients whose abdominal disease was localized to the spleen (IIIsA); 17 IIIA patients with spleen and abdominal lymph node involvement (IIIs+n+A) and 44 stage IIA patients. The three groups were treated concurrently with either extended field irradiation alone or limited field irradiation followed by MOPP chemotherapy. Relapse rates after irradiation alone were 17% for the IIIsA patients; 63% for the IIIs+n+A patients and 25% for the stage IIA patients. Following therapy with irradiation and chemotherapy no relapses occurred among the IIIsA and IIIs+n+A patients while 2/16 (13%) stage IIA patients relapsed. After irradiation alone stage IIIs+n+A patients had a significantly shorter remission duration and survival than the stage IIA patients (p = 0.03 and 0.002, respectively) but remission duration and survival were similar for the IIIsA and IIA patients. When therapy was irradiation and chemotherapy no significant differences in remission duration or survival were noted for the three groups. The most common sites of relapse for the IIIs+n+A patients were extralymphatic (60%) while no extralymphatic relapse have occurred among the IIIA patients (p less than 0.02). The only relapse among the IIIsA patients was at an extralymphatic site. These data have shown that patients with IIIsA Hodgkin's disease have a similar prognosis to stage IIIA disease but after therapy with irradiation along stage IIIs+n+A patients have a poorer prognosis. Combined irradiation and chemotherapy should, therefore, be considered for stage IIIs+n+A Hodgkin's disease when abdominal nodal disease cannot be included in the initial radiation port.

Radiotherapy of glioblastoma multiforme.

✓ A comparison is made between limited field and whole brain irradiation in the treatment of 60 patients with intracranial glioblastomas, 34 of whom were picked at random for either treatment and 26 who were selected for specific treatment. A significant increase in overall survival time and tumor-free period was found in the limited field treatment groups and this was especially significant in those patients selected for limited field treatment. The improved results are felt to be due to the higher dose permissible because of avoidance of more sensitive brain-stem structures. Tumor location in the frontal lobe also appears significant in the longer survival of those patients selected for limited field treatment. More exact localization of the lesion by brain scan, surgery, and angiography also contribute to more efficient treatment and consequently better survival.

Radiation exposure in diagnostic X-ray departments

There is general mutual congratulation over the low levels of occupational exposure usually recorded now for diagnostic radiographers. Certainly, fairly simple improvements in shielding, and in radiographic technique to reduce scatter, have produced a marked improvement over the years, so that dose records are, in most cases, well below the limit of 1·5 rads per year set for non-radiation workers. However, it seems that in diagnostic X-ray departments there is still a very real hazard of accidental exposure of staff, and sometimes of patients, to the main beam. As this will involve limited field irradiation it may not be recorded as an excessive exposure on the film badge, so that accidents may be undetected and unreported.