Biomedical subjects

C Catton

Publications and source records attributed to C Catton.

31 records · Page 2Linked to original sources

PubMed1994

An assessment of prognostic factors in soft-tissue sarcoma of the head and neck.

OBJECTIVE: This study evaluates the outcome, patterns of failure, and prognostic factors in head and neck soft-tissue sarcoma in the adult. DESIGN: A retrospective evaluation of 73 patients treated recently for this rare disease. The minimum follow-up for all patients was 3 years with the living patients having a mean follow-up of 4.6 years. SETTING: All patients were treated between January 1980 and December 1988, at the Princess Margaret Hospital-Ontario Cancer Institute, Toronto, the major sarcoma referral center for a population in excess of 3 million. PATIENTS OR PARTICIPANTS AND INTERVENTIONS: Fifty-two patients were treated with curative intent: 10 by surgery without radiotherapy and 42 with surgery and radiotherapy. Twelve patients received adjuvant chemotherapy. OUTCOME MEASURES: Five-year cause-specific survival, local relapse, and distant failure rates were calculated by the product limit method. Comparisons between survival curves were carried out by the log-rank statistic and Cox regression analysis was performed to assess the influence of prognostic factors. RESULTS: The 5-year cause-specific survival was 62%, with a local relapse rate of 41% and distant relapse rate of 31%. Extension to adjacent structures, high grade, and large lesion size were associated with poorer survival. Gross residual tumor also was associated with high local failure (75% failure) despite the addition of radiation therapy. Those with clear surgical margins or only microscopic involvement fared much more favorably and had similar local control rates (26% and 30% failure, respectively) provided adjuvant radiotherapy was given. However, 68% of patients dying as a result of their sarcoma had uncontrolled local disease because of the high incidence (27%) of gross residuum following surgery in this series. CONCLUSIONS: This series highlights the absolute necessity for resection of all overt disease with planned adjunctive radiotherapy and appropriate reconstruction in most cases. This is achieved more easily in the setting of a specialized sarcoma treatment unit.

Adolescent↗

PubMed1994

Histological necrosis in soft tissue sarcoma following preoperative irradiation.

Forty-eight patients with soft tissue sarcomas that presented adverse features for treatment by limb salvage surgery and postoperative irradiation were treated by preoperative irradiation and surgery using a consistent protocol. Following resection, the extent of histological necrosis in the specimen was scored according to the criteria of Willet et al. Of the 48 cases, 16 (34%) demonstrated Grade 1 response (< 50% necrosis), 15 (31%) Grade 2 (50-80% necrosis), and 17 (35%) Grade 3 (> 80% necrosis). There was a trend toward more extensive necrosis in liposarcoma tumors (53% showing Grade 3 response compared to 26% of other sarcomas). Logistic regression analysis demonstrated a significant relationship between necrosis and tumor size (P < 0.001) with larger tumors having higher grades of necrosis. Tumor grade did not seem to affect the extent of necrosis. In comparison to the previous report of necrosis in soft tissue sarcoma following irradiation, the current analysis revealed a smaller proportion of tumors with Grade 3 necrosis.

Adult↗

PubMed1994

Local control of soft tissue sarcoma of the extremity: the experience of a multidisciplinary sarcoma group with definitive surgery and radiotherapy.

Data gathered on 62 patients with soft tissue sarcoma of an extremity, treated in entirety by an experienced multidisciplinary sarcoma group, were analysed. With a philosophy of emphasising attainment of histologically negative margins at carefully planned limb sparing surgery, combined with either pre-operative or postoperative radiation therapy, a crude local control rate of 95% (59 of 62 patients) at a minimum of 24 months follow-up was obtained. Of 9 patients with microscopically positive margins after definitive surgery, 8 had undergone maximal resection compatible with preservation of function. One of these 9 failed locally, indicating that radiation therapy is effective in eradicating microscopic disease in this tumour. The excellent local control obtained with limb-sparing surgery in this series justifies early referral of patients with these uncommon cancers to an experienced multidisciplinary unit. 26 patients (42%) failed systemically at a minimum of 24 months follow-up, and 19 (30.6%) died of their disease, confirming the need for effective systemic therapy in soft tissue sarcoma. Tumours greater than 10 cm in diameter had a greater risk of systemic relapse.

Adolescent↗

PubMed1994

Wound-healing complications after soft-tissue sarcoma surgery.

One-hundred and eighty patients undergoing limb-salvage surgery for soft-tissue sarcoma from 1986 to 1991 were assessed retrospectively for risk factors associated with major wound-healing complications. Twenty-three of 137 patients (16 percent) treated with primary direct wound closure sustained complications. In univariate analysis, the cross-sectional area of tumor resection, the use of preoperative irradiation, the width of the skin excision, a history of smoking, and a history of diabetes and/or vascular disease were associated with wound failure. Multivariate analysis revealed that preoperative irradiation (p = 0.04) and resection diameter (p = 0.017) accounted for the risk of complications. Eighteen additional patients were treated empirically with distant vascularized tissue transfer following preoperative irradiation because of concerns regarding potential wound complications. The lower complication rate in this group suggested that vascularized tissue transfer may be beneficial in lowering wound complication rates.

Adolescent↗

PubMed1993

Outcome and prognostic factors in soft tissue sarcoma in the adult.

PURPOSE: To evaluate the outcome, patterns of failure and prognostic factors in this rare disease in adult patients treated at a single institution in the modern era. METHODS AND MATERIALS: The records of all patients (389 cases) with soft tissue sarcoma in the extremities, torso (excluding retroperitoneum), and head and neck managed between 1980 and 1988 were reviewed. A curative (radical) approach was used in 321 patients of whom 10% were recurrent lesions. The local management consisted of surgery alone in 54 cases, surgery and radiotherapy in 250 and radiotherapy alone in 17. Adjuvant chemotherapy was used as a policy for high grade lesions in the initial five years of the study (98 cases), but was omitted subsequently. RESULTS: Extremity lesions fared more favourably compared to head and neck and torso lesions (p = 0.02) with respect to survival. Extremity and torso lesions had significantly better local control (p < 0.0001) than in the head and neck where local failure was a common cause of death. A multiple Cox regression analysis revealed that resection margins, local extension of tumor, age at diagnosis, and grade correlated with local relapse and distant relapse was also associated with local extension, high grade and in addition, large lesions. Size appeared especially predictive for distant failure, the most common cause of death. Distant failure was not influenced by the use of adjuvant chemotherapy. Patients treated for recurrence in this series had significantly worse survival due to increased distant failure despite similar local control to primary cases. CONCLUSION: This series highlights the overall problem of distant failure in this disease. It also reaffirms the importance of obtaining local control both in the head and neck, where uncontrolled local disease is the major cause of death, and in general since local relapse appears to increase the risk of distant failure. It appears that the current staging systems should be reviewed in the light of the apparent effect of different prognostic factors.

Actuarial Analysis↗

PubMed1993

Phase I study of hyperfractionated whole brain irradiation (HWBI) in the treatment of primary cerebral lymphoma.

The poor prognosis for primary cerebral lymphoma following conventional radiation therapy has generally been attributed to high local relapse rates despite initial local control. Hyperfractionated radiation therapy may improve the therapeutic ratio by allowing higher total radiation doses to be prescribed without exceeding the radiation tolerance of the central nervous system (CNS). Eight patients entered a study of hyperfractionated whole brain irradiation (HWBI) between October 1988 and May 1991. The prescribed dose was 64.8 Gy in 54 fractions over 5.5 weeks. All patients were followed clinically and with computed tomographic scanning. Additional investigations to discriminate between lymphoma recurrence and radionecrosis included magnetic resonance imaging (MRI), thallium-201 single photon emission computed tomography (SPECT), and immunocytological examination of the cerebrospinal fluid (CSF). A complete remission as seen on CT scan was achieved in all cases. The overall median survival was 102 weeks. Six patients initially deteriorated neurologically without evidence of tumour recurrence. Three patients have died without evidence of recurrence at 18, 62 and 128 weeks. As of 31 May 1992, three patients remain alive, two with radiation brain injury at 147 and 184 weeks. Treatment toxicity prompted study closure in September 1991. The hyperfractionation regimen used is reported by others to be free from significant morbidity. The pathogenesis of cerebral lymphomas (diffuse disease, angiotropism, subependymal involvement) may adversely affect CNS radiation tolerance.

Adult↗

PubMed1991

Wound healing complications in soft tissue sarcoma management: comparison of three treatment protocols.

A prospective, nonrandomized comparison of three treatment protocols was undertaken in 45 patients with soft tissue sarcoma designated preoperatively as being at high risk of wound healing complications. All patients underwent complete resection of the gross tumour mass (5 with positive and 40 with negative microscopic margins). Fourteen patients received postoperative adjuvant irradiation (group I), 16 preoperative irradiation (group II), and 15 preoperative irradiation and vascularized tissue transfer to the surgical bed after resection (group III). Major wound healing complications (defined as complications requiring at least 1 further surgical procedure) were lower in group III patients (chi-square = 5.57, P less than 0.03), as was the mean postoperative hospital stay (P less than 0.02, analysis of variance), and the mean number of secondary surgical procedures. Multivariate analysis showed that the only variable influencing length of stay was the use of tissue transfer. Careful intraoperative assessment of the adequacy of resection is essential prior to performing vascularized tissue transfer to ensure that tumour contamination of the donor site is avoided. Since this study is a nonrandomized clinical trial using sequential distribution of patients to the treatment groups, the data should be considered as preliminary, rather than definitive, evidence of the efficacy of vascularized tissue transfer.

Combined Modality Therapy↗

PubMed1991

Preoperative and postoperative irradiation of soft tissue sarcomas: effect of radiation field size.

For the treatment of soft tissue sarcomas it has frequently been staged but not quantitatively demonstrated, that the volume irradiated is smaller when irradiation is given preoperatively as compared to postoperatively. In this study the field size used for preoperative irradiation was compared with that necessary in the same patient had the radiation been given postoperatively. Twenty-six patients with soft tissue sarcomas of the extremity, groin, and shoulder girdle who had received preoperative irradiation were resimulated following surgery to determine the size of the postoperative field. The simulation was performed by a physician not involved in the preoperative treatment planning. Preoperatively a radial margin of 5 cm around the tumor was used for low and intermediate grade and 7 cm for high grade sarcomas. Postoperatively the same margins were used but around the surgical field. Twelve patients underwent a wide resection and 14 patients a resection followed by vascularized tissue transfer to the surgical bed. The median follow-up was 22 months (range 13-46). No local recurrences and two cases of distant metastasis were observed. Independently of surgical procedure and tumor grade, the size of the preoperative radiation field and number of joints included in the field were significantly smaller than that of postoperative radiation (p less than 0.001). In two patients preoperatively and four patients postoperatively, the radiation field involved the whole circumference of the limb. Provided that equivalent radiation time-dose-fraction parameters are used and that the complication rate is proportional to the radiation field size, late complications may be less after preoperative irradiation than after post-operative irradiation.

Adolescent↗

PubMed1991

Current status of radiosurgery for arteriovenous malformations.

Cerebral arteriovenous malformations (AVM), regardless of the mode of discovery, have an annual risk of hemorrhage of approximately 4 percent. A progressive obliterative vasculitis culminating in the occlusion of an AVM may be induced by the administration of radiation doses of approximately 20 Gy given in a single fraction. The process takes about two years and occlusion occurs in approximately 80% of patients so treated. Such a dose may be accurately administered to AVMs up to 3 cm in diameter with very little radiation imparted to the adjacent brain by means of multiple highly collimated radially arranged cobalt sources (the Gamma Knife) or by means of a modified linear accelerator turned through an arc or arcs with the target AVM as the centre of rotation. The Gamma Knife and the modified linear accelerator have nearly equal accuracy. Recent experience with modified linear accelerators indicates efficacy equal to the Gamma Knife. Both devices are effective treatment for small AVMs but the cost of modifying a pre-existing linear accelerator is only a few percent of the acquisition and installation costs of the Gamma Knife.

Evaluation Studies as Topic↗

PubMed1991

Fractures following limb-salvage surgery and adjuvant irradiation for soft-tissue sarcoma.

In a prospective study, consecutive patients were treated for soft-tissue sarcoma (STS) by wide resection and adjuvant irradiation. Twelve patients had resection of bone to achieve a tumor free margin; five of these patients were left with lower extremity open segmental cortical defects in the high-dose radiation field. Four of the five patients with cortical defects suffered a fracture through the defect more than six months after surgery. Only one of 71 patients not treated with bony resection suffered a late fracture. Patients requiring bony cortex resection for STS of the lower extremity should be considered at risk for late fracture if adjuvant irradiation is prescribed.

Adult↗

PubMed1990

Gated magnetic resonance imaging of metastatic intracardiac malignant fibrous histiocytoma.

We report a patient with right intraventricular metastatic sarcoma who underwent gated magnetic resonance (MR) imaging. The study provided good images of the tumor, though definition was degraded by signal from slow flowing blood. The demonstration of cardiac anatomy was excellent, and this was helpful in planning subsequent radiotherapy. We conclude that gated MR imaging is a valuable supplement to two-dimensional echocardiography in the diagnosis and management of cardiac metastases. This case also illustrates that extensive intracardiac disease can be present in the absence of marked clinical symptoms.

Aged↗

PubMed1990

The inguinal sarcoma: a review of five cases.

A review of five patients who presented during a 3-year period with sarcoma arising in the inguinal canal demonstrated that the lesion is frequently mistaken for a hernia. In three of the patients incomplete excision of the inguinal mass resulted in spread of the lesion beyond the inguinal canal. The authors suggest that neoplastic lesions discovered in the inguinal canal should be evaluated by a small incisional biopsy followed by wide resection if sarcoma is confirmed on pathological examination. Preoperative irradiation and re-excision should be considered if widespread microscopic disease remains after excisional biopsy.

Adult↗

PubMedDate not supplied

Contemporary radiotherapy for soft tissue sarcoma.

This review will detail the role of radiotherapy in the management of soft tissue sarcoma. Particular emphasis will be given to its role as an adjuvant to surgical excision for local curative management. The addition of radiotherapy permits a tissue-conserving operation to be performed, which has functional and cosmetic advantages yet produces local control equivalent to more radical surgery alone. The review will consider the historical evolution of treatment up through recent and contemporary practice. The principles of use will be outlined using available evidence and, where this is lacking, it will be acknowledged with suggestions for improvement. Finally, a brief overview of some technical issues about radiotherapy will be provided.

Combined Modality Therapy↗