In recent years, several nasal cavity and sinus entities have been described with fusion genes. Salivary gland tumors with fusion genes will not be discussed in this article, but it should be kept in mind that accessory salivary glands are present in the nasal cavity and sinuses and can therefore lead to tumoral lesions. Entities with specific or more frequently described rearrangements in the nasal cavities and sinuses are DEK::AFF2 squamous cell carcinomas,;non-intestinal and non-salivary nasosinusal adenocarcinomas, some of which displaying ETV6 gene rearrangements; biphenotypic nasosinusal sarcomas, most of which displaying PAX3 gene rearrangements; and Ewing\'s adamantinoma-like sarcomas, which display the same rearrangements as conventional Ewing\'s sarcomas, mainly the EWSR1::FLI1 rearrangement. Each entity will be described morphologically, immunohistochemically, and prognostically.

BACKGROUND: Dermatofibrosarcoma protuberans (DFSP) is a rare skin tumor. There is no standard recommendation for its surgical management. The currently used histological analysis are HES (hematoxylin eosin saffron) staining and immunohistochemistry for CD34 expression in particular cases. Fluorescent in situ hybridization (FISH) technique is only used to qualify the DFSP as translocated or non-translocated and is not used as a diagnostic method. The aim of our study was to determine by FISH (as a diagnostic method) whether cancerous cells that could not be identified through HES staining±immunohistochemistry were present at the two-centimeter margins that were found to be tumor-free.
METHODS: Samples from patients who underwent surgery between 2010 and 2018 were collected. Intralesional and peripheral (at 2cm margins) paraffin slides were included. An average of 7.4 slides per specimen was analyzed. Firstly, the preselected slides were reread by a senior pathologist to confirm the absence of microscopic findings of DFSP at 2cm margins. Secondly a FISH analysis was used as a quantitative diagnostic approach, in order to find the t(17;22) translocation.
RESULTS: Among the seven specimens that included 2cm margins, two samples presented one or more translocations, which were not visible in standard morphology assessments at two centimeters tumor-free margins.
CONCLUSIONS: FISH analysis can have a new role in defining tumor-free margins. This would reduce the incidence of disease recurrence after resection and improve the post-operative complementary care.

BACKGROUND: Myxoid liposarcoma is a soft tissue sarcoma associated with multifocal metastases at diagnosis. These metastases are asymptomatic and occult on CT and FDG-PET and can alter the therapeutic management and prognosis. In this context, we evaluated the contribution of whole-body MRI to the initial workup of patients with myxoid liposarcoma.
METHODS: This retrospective study was conducted between January 2015 and December 2020 at the Oscar Lambret Center. We enrolled 22 patients who were diagnosed with myxoid liposarcoma and underwent whole-body MRI at diagnosis. The number of metastases at diagnosis, their location, and the visibility of these lesions on CT were evaluated. Associations between clinical features, presence of metastasis, and their impact on management were assessed.
RESULTS: Sixteen patients (72.7%) had non-metastatic disease at the initial diagnosis, and 15 of these patients were managed using local treatment. Six patients (27.3%) had metastases at multiple locations and received chemotherapy. The main locations were the bones (n=5) and lungs (n=3). In five patients with metastases, whole-body MRI demonstrated additional lesions that were not visible on CT (bone and soft tissue lesions). Only the presence of a round cell contingent (P=0.009) was found as a criterion associated with the presence of metastases.
CONCLUSIONS: The patients\' young age, absence of reliable prognostic factors at diagnosis, asymptomatic nature of the lesions, and the benefits of early and targeted therapeutic management encourage the use of whole-body MRI as part of the initial work-up as it seems to provide a better initial staging compared with conventional imaging.

Among the 16,000 new cases of malignant tumors of the head and neck diagnosed in France each year, 10% are not conventional squamous cell carcinomas. These so-called rare cancers are distinguished by their presentation and patterns of failure, which is important to recognize in order to offer specific adapted management and maximize the chances of tumor control. These cancers can be rare by their histology as well as their anatomical location when arising from the paranasal sinuses, salivary glands and ear. The management of these heterogeneous rare diseases of complex treatment has considerably been structured over the last 15 years, in particular via the French ENT Cancer Expertise Network (REFCOR) and international networks and registries (EURACAN, etc.). Structuration also favors research with identification of new entities and setting up of specific therapeutic trials. A first article (part 1) discusses the diagnostic and therapeutic specificities of these rare cancers, and develops the recommendations of the REFCOR concerning rare epithelial tumors, i.e., salivary tumors, sinonasal tumors, variants of conventional squamous cell carcinomas, neuroendocrine carcinomas, malignant odontogenic tumors, and ear tumors. This second article (part 2) is focused on non-epithelial tumors (sarcomas, mucosal melanomas, lymphomas, tumors of uncertain or undetermined malignancy) and describes the organization and missions of the REFCOR.

Uterine leiomyosarcomas represent the most common uterine sarcomas. The prognosis is poor with metastatic recurrence in more than half of the cases. The purpose of this review is to make French recommendations for the management of uterine leiomyosarcomas within the framework of the French Sarcoma Group - Bone Tumor Study Group (GSF-GETO)/NETSARC+ and Malignant Rare Gynecological Tumors (TMRG) networks in order to optimize their therapeutic management. The initial assessment includes a MRI with diffusion perfusion sequence. The diagnosis is histological with a review in an expert center (Reference Network in Sarcoma Pathology (RRePS)). Total hysterectomy with bilateral salpingectomy, en bloc without morcellation, is performed when complete resection is possible, whatever the stage. There is no indication of systematic lymph node dissection. Bilateral oophorectomy is indicated in peri-menopausal or menopausal women. Adjuvant external radiotherapy is not a standard. Adjuvant chemotherapy is not a standard. It can be an option and consists in doxorobucin based protocols. In the event of local recurrence, the therapeutic options are based on revision surgery and/or radiotherapy. Systemic treatment with chemotherapy is most often indicated. In case of metastatic disease, surgical treatment remains indicated when resecable. In cases of oligo-metastatic disease, focal treatment of metastases should be considered. In the case of stage IV, chemotherapy is indicated, and is based on first-line doxorubicin-based protocols. In the event of excessive deterioration in general condition, management by exclusive supportive care is recommended. External palliative radiotherapy can be proposed for symptomatic purposes.

Lymphatic dissemination is thought to be a rare event in breast sarcomas. The decision to perform axillary clearance is challenging. In our prospective cohort, we aimed to evaluate the frequency and factors determining lymph node (LN) involvement in breast sarcomas, with the aim of proposing a decision tree/algorithm for the realization of LN clearance in breast sarcomas.
METHODS: Fourty-five women were surgically treated for breast sarcomas from 1982 to 2020. Angiosarcomas and other sarcomas were compared in terms of LN involvement, recurrence, and mortality.
RESULTS: Twenty-three patients underwent axillary lymphadenectomy. Initial LN involvement was diagnosed in one case of D2-40 positive, primary angiosarcoma for which preoperative imaging detected a suspicious LN confirmed by preoperative histology. Among the 22 patients who had no initial axillary lymphadenectomy, two patients with D2-40 positive angiosarcoma had recurrent cancer in LN (internal mammary group in 1 and homolateral axilla in 1). The average follow-up in the overall population was 6.2 years (±8.3). The cohort\'s overall recurrence rate was 33% (15/45) and the time of recurrence after initial surgery was on average 2.4 years (±3.1). For the three patients with LN metastases, time to recurrence after surgery was 3.7 years (±4.5). There was no significant difference in the overall recurrence rate depending on whether or not lymphadenectomy was initially performed (respectively 26% vs 41% OR=1.11, P=0.29).
CONCLUSIONS: Systematic axillary clearance leads to overtreatment in breast sarcomas. A decision tree, including radiological examination of the axilla, histological type of sarcoma, and D2-40 positivity, could be a decision aid in the choice of axillary clearance.

Patients with chronic inflammatory diseases (IBD) of the digestive tract are known to have an increased risk of colorectal cancer. These are usually adenocarcinomas, and the occurrence of malignant mesenchymal tumours, particularly leiomyosarcomas, is exceptional. We report one case in a 40-year-old woman, followed for 9 years for ulcerative colitis. The tumour measured 2cm in length and infiltrated the entire rectal wall as far as the subserosa. It was composed of fusiform cells, with 5 mitoses for 10 fields at ×400 magnification, and expressing actin, desmin and caldesmone under immunohistochemical study. We review the 2 cases of leiomyosarcomas associated with Crohn\'s disease and 3 cases developed during ulcerative colitis published in the literature.

Thigh loss cover after carcinologic resection of sarcomas can be complex and compromise the vascular tree of the lower limb. We report a case of a patient with recurrent sarcoma of the right thigh. After multiple resections, the femur and hip joint are exposed. The superficial and deep femoral vessels are taken in the excisional piece. The reconstruction is performed by a free musculocutaneous latissimus dorsi flap, anastomosed to the deep inferior controlateral epigastric vessels. The deep inferior epigastric vessels are of sufficient length to join the contralateral hemiabdomen after dissection with a gauge allowing microsurgical anastomoses. They can serve as recipient vessels for a flap covering the contralateral thigh.

Reirradiation and irradiation of sarcoma is often difficult due to the frequent need for a high dose of radiation in order to increase tumor control. This can result in a greater risk of toxicity which can be mitigated with the use of proton therapy. The present review aims to summarize the role of proton therapy in these 2 clinical contexts.

Radiation therapy is a standard treatment for limbs soft tissue sarcomas. Preoperative versus postoperative radiotherapy has been a controversial topic for years. With preoperative irradiation, the treatment volume is more limited, the delivered dose possibly lower and the tumor volume easier to delimit. Only one randomized trial compared these two irradiation sequences. The results in terms of local control and survival were equivalent but the risk of acute postoperative complications was higher if irradiation was administered before surgery. However, in the latest update of this trial, patients who received adjuvant irradiation exhibited more severe late toxicity than those treated preoperatively. In addition, with modern irradiation techniques such as conformal with image-guided intensity modulated radiotherapy and flap coverage techniques, the incidence of complications after preoperative irradiation were lower than historically published rates. Locally advanced proximal sarcomas and the failure of other neoadjuvant treatments are nowadays classical indications for preoperative irradiation. As with other neoadjuvant treatments, induction radiotherapy must be personalized according to the histological subtype, the tumor site and the benefit/risk ratio, which is best appreciated by a multidisciplinary surgical and oncological team in a specialized center in the management of soft-tissue sarcomas.