Pathologic and MR imaging features of benign fibrous soft-tissue tumors in adults.

Benign fibrous (fibroblastic or myofibroblastic) soft-tissue tumors are a heterogeneous group of fibrous lesions with widely varied anatomic locations, biologic behavior, and pathologic features. The four broad categories of fibrous proliferation are benign fibrous proliferations, fibromatoses, fibrosarcomas, and fibrous proliferations of infancy and childhood. The first two categories include nonaggressive fibroblastic lesions such as nodular fasciitis, as well as fibromatoses that demonstrate more aggressive biologic behavior (eg, desmoid tumors). In adults, fibrous tumors are among the most common soft-tissue lesions encountered in clinical practice. MR imaging can be useful for defining the intrinsic signal characteristics, size, and compartmental extension of these lesions. Histologic features of the tumor also may be depicted on T2-weighted MR images. Hypocellular fibrous tumors with dense collagenous components tend to have lower signal intensity on T2-weighted images than do lesions that are more cellular or that contain greater amounts of extracellular myxoid matrix. When interpreting MR images of soft-tissue masses in adults, radiologists should be aware of the clinical behavior, common sites of occurrence, and histopathologic and imaging features of the common benign fibrous soft-tissue tumors.

Impact of intensity-modulated radiotherapy on acute hematologic toxicity in women with gynecologic malignancies.

PURPOSE: To evaluate the impact of intensity-modulated whole pelvic radiotherapy (IM-WPRT) on acute hematologic toxicity (HT) in gynecology patients. METHODS AND MATERIALS: Between February 2000 and June 2001, 36 patients (24 cervix, 12 uterus) received IM-WPRT. The target consisted of the upper vagina, parametria, uterus, and presacral and pelvic lymph nodes. Using commercially available software, seven or nine coplanar IM-WPRT plans were generated. The planning goals were to irradiate the target while minimizing the dose to the small bowel, bladder, and rectum. Pelvic bone marrow (BM) was not a constraint in the planning process. The variables analyzed included white blood count (WBC), absolute neutrophil count (ANC), platelets, and hemoglobin (Hgb) obtained before and weekly during RT. As a comparison, the HT in 88 patients (44 cervix, 44 uterus) treated to the same target volume and total dose (45 Gy) with conventional four-field WPRT was analyzed. In addition, the medullary spaces within the pelvic bones in 10 women were contoured and the average dose-volume histograms representing the pelvic BM were compared between the two groups. RESULTS: IM-WPRT patients had a lower median age (p = 0.008), higher percentage of squamous histologic features (p = 0.04), and were more likely to receive chemotherapy (CTX) (p = 0.02) than were the WPRT patients. No differences were seen in the baseline WBC, ANC, platelet, or Hgb levels between the two groups. Grade 2 or greater WBC, ANC, and Hgb toxicity was seen in 19.4%, 9.1%, and 8.6% of the IM-WPRT patients, respectively. Comparable rates were seen in the WPRT patients (WBC 21.6%, p = 0.79; ANC 8.3%, p = 0.91; Hgb 9.2%, p = 0.94). No Grade 2 or greater platelet toxicity was seen in either group. Significant HT was infrequent in women treated with RT alone and was comparable in the two groups. In contrast, WPRT + CTX patients experienced more Grade 2 or greater WBC toxicity (60% vs. 31.2%, p = 0.08) and developed lower median WBC (2.8 vs. 3.6 microg/dL, p = 0.05) and ANC (1874 vs. 2669, p = 0.04) nadirs than did IM-WPRT + CTX patients. Moreover, CTX was held more often in the WPRT group secondary to HT (40% vs. 12.5%, p = 0.06). Although Grade 2 or greater ANC (23.5% vs. 15.3%) and Hgb (35.2% vs. 15.2%) toxicity were lower in the IM-WPRT + CTX group, these differences did not reach statistical significance (p = 0.58 and p = 0.22, respectively). The comparison of pelvic BM dose-volume histograms revealed that IM-WPRT planning resulted in significantly less BM volume being irradiated compared with WPRT planning, particularly within the iliac crests. CONCLUSION: IM-WPRT has a favorable impact on the risk of acute HT in gynecology patients, particularly in those receiving CTX. Future work is needed to optimize BM sparing in these patients to reduce the risk of significant HT further.