LYMPHATIC SPREAD AND ITS SIGNIFICANCE IN SOFT TISSUE SARCOMAS OF THE EXTREMITIES

Abstract

Background: To look into the incidence of lymphatic spread in Soft Tissue Sarcomas (STS) of the extremities and its relevance to the patient’s prognosis.

Patients & Methods: Retrospective review of 96 patients over a period of 5 years from 1999 to 2004 with a minimum follow up of 8 months. Complete data of every patient was reviewed with particular emphasis on lymph node and distant metastasis. All the patients were seen by one consultant and the histology reports were given by one Pathologist. 2 consultant radiologists were also involved in giving reports.

Results: There were 39 males and 57 females with an average age of 51 years. The average duration of swelling at presentation was 6 months. There was a strong family history of cancer in first degree relatives in 23 patients (24%). Liposarcoma was the commonest tumour (22) followed by Leiomyosarcoma (19), Fibro sarcoma (14), Synovial Sarcoma (12), Rhabdomyosarcoma (10), Histiocytoma (9) and other rare sarcomas. The Trojani grade of the tumours was Grade 1 = 36, Grade 2 = 39 & Grade 3 = 21. No metastasis (mets) were found during pre op. screening in 71 patients (74%) while 11 (12%) had lung mets, 9 (10 %) had lymph node involvement and 5 had liver involvement (4 %). 4 had multiple organ involvement on presentation. All except 6 patients had either wide local or radical excision of the tumour. The average interval between presentation and definitive treatment was 28 days. 9 of the patients with lymph node mets underwent nodal clearance during primary surgery. 2 turned out to be reactive hyperplasia while 7 proved to be malignant. 22 of the 71 patients (31 %) with no mets pre op. developed mets during follow up at an average duration of 11 months (11 to lungs, 8 to regional lymph nodes, 2 to liver and one to bone. 4 patients had multiple mets) In addition to this, there was local recurrence in 12 patients of whom 9 had incomplete excision during primary surgery. Of the total 15 patients who had proven lymph node mets, 5 came from Rhabdomyosarcoma, 4 from Leiomyosarcoma, 3 each from Lipo & Synovial sarcoma. The average life span in patients with lymph node involvement was 13 months in total when compared to 31 months for others. As on 31-3-2005, 39 were dead and the rest were alive. The average life span of the patients who died from the time of confirmed diagnosis was 23 months. The average life span for Rhabdomyosarcoma was 8 months, Histiocytoma was 12 months, Liposarcoma was 19 months, Leiomyosarcoma was 28 months and Synovial sarcoma was 36 months. Patients with Trojani grade 3 STS died at an average of 9 months when compared to 38 months for grade 1.

Discussion: There is a 16% spread to regional lymph nodes. It appears that lymph node involvement is indicative of micrometastatic disease elsewhere. Excision of the lymph nodes during primary surgery did not improve the life expectancy.

Conclusion:

1. Lymph node involvement is a poor prognostic sign

2. While removal of clinically suspicious lymph nodes is reasonable, there appears to be little justification for treating clinically uninvolved draining regional lymph nodes

3. Therapeutic lymph node dissection might be indicated as part of the palliative management

4. The presence of regional lymph node metastasis at any time should be interpreted as an expression of systemic tumour spread and treated palliatively only.