Liposarcoma a clinicopathologic, radiographic and prognostic study.

The present investigation is a clinicopathologic, radiologic and prognostic study of 122 liposarcomas registered in the Swedish Cancer Registry between 1958 and 1966. The incidence of liposarcoma in Sweden was estimated to be 2.5 cases per million inhabitants per year. The liposarcomas were divided into 4 main subtypes according to WHO's recommended classification (1969): well-differentiated (33 cases), myxoid (22 cases), rundcell (14 cases) and pleomorphic types (21 cases). When predominantly well-differentiated or myxoid liposarcomas contained areas of round-cell or pleomorphic types (24 and 8 cases, respectively), they were classified separately, thus adding 2 further subtypes to our classification. The validity of this histologic classification was emphasized by the prognostic study, based on a 10 year follow-up. The differential diagnosis for each of the 4 main subtypes is discussed. Three well-differentiated, lipoma-like liposarcomas which contained highly vascular hibernoma-like areas are described. Two well-differentiated liposarcomas situated in the neck and upper part of the back, respectively, of elderly patients included area similar to "spindle-cell lipoma" (Enzinger). An intracytoplasmic network of birefringent fibers with the staining reaction of collagen was found in 2 well-differentiated fibrosing liposarcomas...