The Effect of chemo- and radiotherapy on tumor necrosis in soft tissue sarcoma- does it influence prognosis?

BACKGROUND

Soft tissue sarcomas (STSs) are a heterogeneous group of tumors. Wide surgical resection is standard, often combined with neoadjuvant chemotherapy, radiotherapy, or both. Studies have shown the predictive value of tumor necrosis in bone sarcoma (BS); however, the role of necrosis in STS after neoadjuvant therapies is still unclear. This study aimed to investigate the role of chemo- and radiotherapy in the formation of tumor necrosis and to evaluate the influence of tumor necrosis on overall survival and local recurrence-free survival. Data from BS patients and patients who did not receive neoadjuvant therapy were compared.

METHODS

A total of 779 patients with STS or BS were treated surgically. In all patients, tumor-specific factors such as type, size, or grading and the type of adjuvant therapy were documented. Local recurrence (LR), the diagnosis of metastatic disease, and survival during follow-up were evaluated.

RESULTS

A total of 565 patients with STS and 214 with BS were investigated. In STS, 24.1% G1 lesions, 34.1% G2 lesions, and 41.8% G3 lesions were observed. Two hundred twenty-four of the patients with STS and neoadjuvant therapy had either radiotherapy (RTx) (n = 80), chemotherapy (CTx) (n = 93), or both (n = 51). Three hundred forty-one had no neoadjuvant therapy at all. In STS, tumor necrosis after neoadjuvant treatment was significantly higher (53.5%) than in patients without neoadjuvant therapy (15.7%) (p < 0.001). Patients with combined neoadjuvant chemo-/radiotherapy had substantially higher tumor necrosis than those with radiotherapy alone (p = 0.032). There was no difference in tumor necrosis in patients with combined chemo-/radiotherapy and chemotherapy alone (p = 0.4). The mean overall survival for patients with STS was 34.7 months. Tumor necrosis did not influence survival in a subgroup of G2/3 patients. In STS with no neoadjuvant therapy and grading of G2/3, the correlation between necrosis and overall survival was significant (p = 0.0248). There was no significant correlation between local recurrence (LR) and necrosis.

CONCLUSION

STS shows a broad spectrum of necrosis even without neoadjuvant chemo- or radiotherapy. After CTx or/and RTx necrosis is enhanced and is significantly pronounced with a combination of both. There is a trend toward higher necrosis with CTx than with RTx. Grading substantially influences the necrosis rate, but necrosis in soft-tissue sarcoma following neoadjuvant therapy does not correlate with better survival or a lower local recurrence rate, as in bone sarcomas.

Ultrasound and contrast enhanced CT imaging of a colon mesentery leiomyosarcoma

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Primary mesenteric leiomyosarcoma is a very rare, aggressive neoplasm.

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Tumour recurrence and metastatic spread is a significant risk following surgical treatment.

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Follow-up is warranted and likely improves patient survival rates.

Primary leiomyosarcoma of the colon mesentery is an extremely rare neoplasm, and only a small number of cases have been reported. We describe a case of leiomyosarcoma originating in the colonic mesentery, in a 68-year-old woman. Ultrasound showed a heterogeneous mass with varying vascularization in the left fossa. Central areas of the mass were hypoechoic, without detectable vascularization. Contrast enhanced computed tomography (CECT) of chest and abdomen showed a contrast enhanced tumour, with central non-enhanced areas. The tumour was radically resected and histopathology showed primary leiomyosarcoma. Two years after primary surgery, follow-up CECT revealed a local recurrence, which was re-resected. Subsequent follow-up CECT since have shown no sign of recurrence.

Prognostic information in soft tissue sarcoma using tumour size, vascular invasion and microscopic tumour necrosis-the SIN-system

We have earlier devised a system for soft tissue sarcoma (STS), based on three negative prognostic features: large tumour size, vascular invasion, and microscopic tumour necrosis, the SIN-system. Tumours which exhibit 2 or 3 of these features are categorised as high-risk, the others as low-risk. We have now tested this system for reproducibility both as regards recognition of its components, and as regards prognostic strength in patients from another institution. We have also compared it with the American Joint Committee on Cancer (AJCC) system. 200 patients with STS were analysed, all had been treated by surgery, in 97 patients combined with radiotherapy. The median follow-up for the 117 survivors was 10 (1.5-27) years. Without knowledge of the clinical data, three groups of pathologists independently reviewed original slides from all of the tumours. Based on the factors, the tumours were classified as high-risk or low-risk. The prognostic strength was compared using the results obtained by the different observers. Concordance in recognition of vascular invasion, tumour necrosis, and overall grading was seen in 156 (78%), 154 (77%), and 167 (84%) of the 200 tumours, respectively. Based on the different observers' grading, the cumulative 5-year metastasis-free survival rate (MFSR) varied for patients with low-risk tumours between 0.85 and 0.80, and for patients with high-risk tumours between 0.48 and 0.43. The Kappa-value for grading between all three groups of observers was 0.77. The SIN-system gave more clinically useful prognostic information than the AJCC system. Useful prognostic information in STS can be obtained by using tumour size, vascular invasion and microscopic tumour necrosis. This system provides two distinct prognostic groups, and has a high reproducibility.

Dermatofibrosarcoma protuberans. CT findings with pathologic correlation in 6 cases

PURPOSE

To characterize the CT findings of dermatofibrosarcoma protuberans.

MATERIAL AND METHODS

CT and pathologic specimens of 6 patients with dermatofibrosarcoma protuberans (5 in the trunk and 1 in the leg) were retrospectively reviewed.

RESULTS

CT clearly defined the tumors in the dermis and subcutaneous tissue with a characteristic, if not pathognomonic, protrusion. On postcontrast CT, 3 tumors showed marginal enhancement and central low density, while the others showed homogeneous enhancement. Pathologically, the marginal enhancement on CT corresponded to fibrosarcomatous changes, and the central low density to necrosis. The tumors with homogeneous enhancement had no sarcomatous changes.

CONCLUSION

CT allows detection and precise anatomic localization of dermatofibrosarcoma protuberans. Marginal enhancement with central low density on CT may suggest a relatively poor prognosis.

Liposarcoma: a population-based epidemiologic and prognostic study of features of 43 patients, including tumor DNA content

Different conceptions exist regarding the epidemiology and prognosis of liposarcoma, and several classification systems are in use. We analyzed a population-based, 25-year series of 43 patients with liposarcoma of the extremity or trunk wall. Follow-up was complete. The annual incidence was 0.12/10(5). The thigh was the most common location. One of 6 tumors was subcutaneous. Deep-seated tumors were larger than s.c. tumors. Among the 42 surgically treated patients, grade II (4-grade scale) was the most common malignancy grade. Four tumors were well-differentiated, 24 were predominantly myxoid, 4 predominantly round-cell, and 10 were predominantly of pleomorphic type. The 5-year metastasis-free survival rate was 69%. By univariate analysis increasing malignancy grade, tumor necrosis, vascular invasion, mitotic count, subtype other than well-differentiated, and high cellularity were prognostic for metastatic disease. However, in the multivariate analysis only tumor necrosis was an independent risk factor. Tumor necrosis should be considered when prognosis of liposarcoma of the extremity and trunk wall is evaluated.