Recurrence and Mortality after Surgical Treatment of Soft Tissue Sarcomas

Motanya JB1, Saidi H2

1 − Molo District Hospital, Nakuru, Kenya

2 − School of Medicine, University of Nairobi.

Correspondence to: Dr. J.B. Motanya, P.O. Box 156, Molo 20106. Kenya. Email: jms.motanya@gmail.com

Abstract

Background: The recurrence rate after soft tissue sarcoma (STS) treatment ranges between 20-25 % ,and usually occurs within 2-3 years after primary surgery. In Africa, many of the patients present late, access to adjuvant therapy is not guaranteed either. The basis of this study was to establish patterns and factors affecting recurrence and mortality after surgical treatment at a national referral medical facility.

 

Methods: A five and a half years retrospective study between January 2003 and June 2007 and a six months prospective follow-up arm between July 2008 and March 2009.

 

Data reviewed from all eligible surgically treated patients were demographic variables, duration of symptoms, anatomical distribution, investigations, adjuvant therapy, tumour type, size, grade and stage and surgical margins status. The outcome variables were tumour recurrence and death.

 

Results: Mean age was 32.52+18.17 years. The male/ female sex ratio was 0.97:1. The mean duration of symptoms was 10.87+18.75 months. The extremities had the most number of cases (62%). Fibrosarcoma was the most common histological type (36.0%) and the mean tumour size was 13.0 +7.36 cm. Most (44.7%) patients presented with high grade tumours and 78.0 of the patients presented with a recurrence. Most of the recurrences (71.7%) occurred within the first year of treatment.

 

Failure to get adjuvant therapy (p<0.001), tumour size >5cm (p=0.02), advanced stage (III and IV) (p<0.001), and positive microscopic margins (p<0.001) were adverse prognostic factors for recurrence. Presentation with a recurrent tumour (p<0.027), failure to receive adjuvant therapy (p<0.001), advanced stages (III and IV) (p<0.001), positive microscopic margins (p<0.001), and high grade tumours (p<0.001), were predictors for

death.

 

Conclusions

Advanced stages of STS, higher histological grades, positive microscopic surgical margins, and failure to receive adjuvant treatment influenced both recurrence and mortality after surgical treatment. Better outcome results from surgical treatment of soft tissue sarcomas may be achieved if efforts to treat them earlier were to be a reality.

Introduction

Soft tissues sarcomas (STS) are an uncommon biologically and histologically heterogeneous group of malignant tumours of mesenchymal origin(1,2). They comprise about 1-3 % and 12-15 % of all malignant tumours in adults and children respectively (3,4). More than 50 different histological subtypes of soft tissue sarcoma have been identified (1). The commonest areas of distribution in the body are the extremities (upper and lower limbs) and the intra-abdominal and retroperitoneal regions. The head and neck is the least involved region (5,6).

 

Most soft tissue sarcomas that are adequately treated will result in a cure (7-9). However, treated patients may end up with recurrences, necessitating re-treatment. Most large series report recurrence rates of between 20 and 25 %. This usually occurs 2-3 years after the primary treatment with two thirds of recurrences developing within 2 years of primary treatment (10). In Africa, patients with soft tissue sarcomas generally present late and have to travel long distances to treatment centers. Many do not benefit from radiotherapy and chemotherapy after the surgical procedure due to inadequate resources. As such recurrence rates may be much higher than those reported elsewhere (11). In the few African series of soft tissue sarcomas , no outcome measures were evaluated (6,11). We studied the pattern and determinants of tumour recurrence at the Kenyatta National Hospital in Nairobi (KNH).

 

Methods

This study was conducted at the Kenyatta National Hospital (KNH), a referral and teaching hospital in Kenya. Between 2002 and 2007, 436 cases of STS were recorded in the KNH pathology department. Of these, all patients who underwent resection with curative intent at various units were included. All age groups were included in this study. Patients excluded were those, (i) with tumours of bone origin (ii) whose records were not available or those whose records were incomplete (iii) with gross involvement of the resection margins (iv) who had other primary treatment modalities other than surgery.

 

This was a five and a half years retrospective descriptive study between January 2003 and June 2008. A six month prospective arm was added to the study and sixteen consecutive patients were recruited between July 2008 and September 2008 and followed up for 6 months.

 

The patient files were obtained from the records department and details transferred into a study questionnaire. Demographic data included age and gender of the patient. Clinical data included the duration of disease symptoms, the body region involved, radiological diagnostic tests done, the nature of surgical treatment offered, and the use of adjuvant therapies. Pathological data included the histological type, tumour size, grade, stage, and the microscopic margin status. Follow-up information included the site of recurrence, follow-up period and status (alive, dead, and lost to follow-up) at last follow-up.

 

Data were analyzed using the SPSS version 11.1, and results presented in tables and graphs. Univariate analyses were used to obtain relationships between various patient and tumour variables and recurrence. The Chi square test was used to compare the proportions of different variables for outcomes. The independent t-test was used to determine the relationship between means of various continuous variables and outcomes. The level of statistical significance was set at p < 0.05. Approval for the study was granted by the KNH Ethics and Research Committee.

 

Results

The mean age was 32.52 +18.17 years and the median age was 32.0 years. The age range was from 0.5 to 75 years. All age groups were affected (Fig. 1).There were 74 males (49.3%), and 76 females (50.7%).