Recommandations pour la pratique clinique : mise à jour 2006 des Standards, Options et Recommandations pour l'irradiation des patients adultes atteints de sarcome des tissus mous (sarcome des membres, sarcomes rétropéritonéaux et sarcomes utérins)

[Radiotherapy for soft tissue sarcomas: Technical evolution and impact on clinical benefit]

The standard treatment for extremity soft tissue sarcomas is based on the association of surgery and radiotherapy. This strategy allows local control improvement with the risk of increased toxicity. There is therefore a growing interest to identify those patients who will benefit from radiotherapy and those who will have the same local control with surgery alone. Furthermore, the development of toxicity has been correlated with the extension of the irradiated volume and the volume receiving high doses. Technological development as intensity modulated radiotherapy and image-guided radiotherapy allows limited irradiated volume improving the protection of the organs at risk leading to clinical benefit improvement. Moreover, efforts are being done to improve local control for the patients at high risk of local relapse. In this paper, we discuss all these mentioned aspects.

Utility of 18F-FDG PET with a semi-quantitative index in the detection of sarcomatous transformation in patients with neurofibromatosis type 1

Background

Malignant peripheral nerve sheath tumors (MPNSTs) are a serious complications of neurofibromatosis type 1 associated with poor prognosis and deeper lesions can be difficult to diagnose. 18-FDG PET improves the detection of malignancies. However, the criteria for malignancy, notably the SUVmax threshold, are not standardized. Therefore, the aim of the study was to evaluate a semi-quantitative index for the reproducible detection of MPNST with FDG PET.

Methods

It is a multicenter retrospective study conducted between 2000 to 2012. All patients with NF1 referred for suspected MPNST underwent PET. Since SUVmax was not available until 2004 in our centers, we had to settle for the semi-quantitative method used at that time, the uptake ratio between the tumor and the normal liver (T/L ratio) with 1.5 as the cut-off for malignancy. When dedicated PET with SUVmax became available, the semi-quantitative analysis of PET images remained, along with SUVmax.

Results

113 patients with 145 tumors were included. PET assessment revealed 65 suspected lesions with T/L >1.5 and among these, 40 were MPNSTs. 80 tumors were classified as non-suspicious, and 79 were benign. The 1.5 T/L cut-off had a negative predictive value (NPV) of 98,8% and a positive predictive value of 61,5%. The positive likelihood ratio (LR) was 4,059, the negative LR was 0,032 with 97% sensitivity and 76% specificity.

Conclusions

This study, which is among the largest published, confirms the utility of PET for detecting NF1-associated MPNSTs. A semi-quantitative index, the T/L ratio with a cut-off of 1.5, allowed sensitive and specific differentiation of malignant from benign tumors better than SUVmax. When T/L was <1.5, MPNSTs were ruled out with 98,8% NPV. When T/L was >1.5, there was a strong suspicion of malignancy. This semi-quantitative analytical method is as simple as SUVmax, but is more sensitive, more reproducible and non-user-dependent.

[Uterine leiomyosarcoma: epidemiology, pathology, biology, diagnosis, prognosis and treatment]

Uterine leiomyosarcoma is a rare disease with a poor prognosis. The rarity of this tumor needs a specialized management in tertiary reference centers in order to provide patients with optimal diagnostic, prognostic and therapeutic care. The pathological diagnosis relies on the presence of three characteristics in proliferating smooth muscle cells: necrosis, cytologic atypia and mitosis. Despite progress in the knowledge of the biology of these tumors, no oncogenic driver has been found. Prognosis depends mainly on the age of the patient, race, FIGO stage, mitotic index and hormonal receptor expression in the tumor. Surgery is one of the cornerstones of management and cytotoxic chemotherapy is the mainstay of treatment in metastatic disease with a potential role in the adjuvant setting. In locally advanced or metastatic disease, prognosis is poor with a median overall survival of about 12 to 14 months despite a 30% response rate to polychemotherapy regimens. Anti-angiogenics and hormonal therapy have a role to play in the setting of metastatic disease. It is mandatory to include such patients in clinical trials aiming to improve the therapeutic management of these patients. Multimodal therapy can improve the prognosis of selected patients too.

[Surgery and postoperative radiation therapy in primary retroperitoneal sarcomas: experience of the cancer centre Alexis-Vautrin]

PURPOSE

Surgical resection remains the standard treatment for patients with resectable retroperitoneal sarcomas. The aim of this study was to retrospectively analyse the outcomes of patients with primary retroperitoneal sarcoma.

PATIENTS AND METHODS

We analysed data of 50 patients with primary retroperitoneal sarcoma who underwent curative-intent resection from 1975 to 2008. External beam radiotherapy and chemotherapy were delivered postoperatively. Demographics, surgical, pathological variables and chemo/radiation therapy were analysed as prognosis factors.

RESULTS

There were 22 males and 28 females (mean age 54 ± 13 years). Surgery required visceral resections in 30 patients. There were 16 leiomyosarcomas, 25 liposarcomas and eight other sub-types. Twenty-one patients had clear surgical margins. Twenty-eight patients received postoperative external beam radiotherapy (median 45 Gy) and 15 received chemotherapy. At the end of the follow-up (median 55 months), local recurrence occurred in 39% (n=14) among R0/R1 resection group (n=36). Postoperative external beam radiotherapy tends to increase the time of local recurrence from surgery (27 vs. 13 months, P=0.05). The overall survival rates were 81%, 55% and 46% at 1, 3 and 5 years, respectively. Although R0 resection (P=0.01), well tumour differentiation (P=0.004) and postoperative external beam radiotherapy (P=0.02) significantly influenced overall survival in univariate analysis, only R0 resection was an independent prognostic factor in a multivariate analysis.

CONCLUSION

We confirm the pre-eminence of radical surgery with negative margins as major prognostic factor and the benefit of postoperative radiotherapy.

[Intensity modulated radiotherapy as adjuvant post-operative treatment for retroperitoneal sarcoma: acute toxicity]

PURPOSE

To assess the acute toxicity of intensity modulated radiotherapy as post-operative adjuvant treatment for retroperitoneal sarcoma.

PATIENTS AND METHODS

Patients who received adjuvant intensity modulated radiotherapy from January 2009 to September 2010 were retrospectively reviewed.

RESULTS

Fourteen patients entered the study (seven primary tumours and seven relapses). All tumours were liposarcoma and had macroscopically complete resection, epiploplasty was systematically realized. Median tumour size was 21 cm (range: 15-45), median planning target volume was 580 cm(3) (range: 329-1172) and median prescribed dose was 50.4 Gy (range: 45-54). Median follow-up was 11.5 months (range: 2-21.4). Acute toxicity was mild: acute digestive toxicity grade 1-2 occurred in 12/14 patients (86%). However, there was no weight loss of more than 5% during radiotherapy and no treatment interruption was required. Two months after completion of radiotherapy, digestive toxicity grade 1 remained present in 1/14 patients (7%). One case of grade 3 toxicity occurred during follow-up (transient abdominal pain). Three relapses occurred: two were outside treaded volume and one was both in and outside treated volume.

CONCLUSIONS

Intensity modulated radiotherapy in the postoperative setting of retroperitoneal sarcoma provides low acute toxicity. Longer follow-up is needed to assess late toxicity, especially for bowel, kidney and radio-induced malignancies.

Phase I combination study of trabectedin and doxorubicin in patients with soft-tissue sarcoma

PURPOSE

To determine the dose of trabectedin plus doxorubicin with granulocyte colony-stimulating factor support associated with manageable neutropenia and acceptable dose-limiting toxicities (DLT) in patients with recurrent or persistent soft-tissue sarcoma.

METHODS

In this phase I, open-label, multicenter trial, patients previously treated with 0-1 prior chemotherapy regimens excluding doxorubicin, an Eastern Cooperative Oncology Group performance status 0-1, and adequate organ function received a 10- to 15-min i.v. infusion of doxorubicin 60 mg/m(2) immediately followed by a 3-h i.v. infusion of trabectedin 0.9 to 1.3 mg/m(2) on day 1 of a 3-week cycle. Because four of the first six patients experienced DLT-defining neutropenia during cycle 1, all subsequent patients received primary prophylactic granulocyte colony-stimulating factor. The maximum tolerated dose was the highest dose level with six or more patients in which less than one-third of the patients experienced severe neutropenia or DLT. Blood was collected during cycle 1 for pharmacokinetic analyses. Adverse events, tumor response, and survival were assessed.

RESULTS

Patients (N = 41) received a median of six cycles of treatment (range, 2-13). The maximum tolerated dose was trabectedin 1.1 mg/m(2) and doxorubicin 60 mg/m(2). Common grade 3/4 treatment-emergent adverse events were neutropenia (71%), alanine aminotransferase increase (46%), and thrombocytopenia (37%). Overall, 5 (12%) patients achieved a partial response and 34 (83%) maintained stable disease. Median progression-free survival was 9.2 months. Doxorubicin and trabectedin pharmacokinetics were not altered substantially with concomitant administration.

CONCLUSION

The combination of doxorubicin 60 mg/m(2) followed by trabectedin 1.1 mg/m(2) every 21 days is safe and active in patients with soft-tissue sarcoma.

Centralised treatment of soft tissue sarcomas in adults

The clinical research developed in specialised centres and oncologic cooperative groups has permitted various scientific societies to collect recommendations used in the treatment of soft tissue sarcomas (STS) and incorporate them into clinical practice guidelines (CPG). Some studies have been conducted in diverse healthcare ambits to assess the influence of CPG. This revision of the medical literature analyses the impact that healthcare management -centralised or otherwise- and clinical practice in conformity with CPG have on the clinical outcome variables of STS. Eight CPG have been identified, as well as 12 conformity studies or audits. These conformity studies and audits demonstrate that the grade of adaptation of medical interventions with CPG, medical healthcare in reference centres and procedures of referrals to these centres, as well as the process of organising healthcare teams into Sarcoma Committees, have a significant influence on clinical outcome. We can conclude that excellent healthcare of STS implies the adaptation of healthcare practice to CPG, the existence of Reference Centres guided by Sarcoma Committees, and the observance of strict referral procedures within the Healthcare Area.