Desmoid tumors are benign monoclonal fibroblastic or myofibroblastic neoplasms, characterized by local invasiveness and high rates of recurrence. Desmoid tumors must be distinguished from benign fibroblastic and myofibroblastic lesions, as well as from low-grade sarcoma, which can appear histologically similar to desmoid tumors. This differential diagnosis can be very difficult, especially when diagnosis is based on a core needle biopsy. On the molecular level, most sporadic desmoid tumors are associated with mutations of the β-catenin gene (CTNNB1). A minority of desmoid tumors are associated with Gardner syndrome and mutations of the familial adenomatous polyposis gene. We identified the common CTNNB1 mutations associated with sporadic desmoid tumors by direct sequencing: in (i) 260 cases of typical desmoid tumors; and (ii) in 191 cases of spindle cell lesions, which can morphologically 'mimic' desmoid tumors. Formalin-fixed paraffin-embedded tissues were obtained via core needle biopsy (n=150) or open biopsy/surgical excision (n=301). Only 16 cases (4%) were not analyzable (Bouin's fixed tissue). CTNNB1 mutations were observed in 223 of 254 (88%) of sporadic desmoid tumors. No CTNNB1 mutations were detected in all other lesions (n=175) studied. CTNNB1 sequencing can be easily and reliably done using tissues obtained via core needle biopsy. Detection of CTNNB1 mutations in formalin-fixed paraffin-embedded tissues among spindle cell lesions is proposed as a specific diagnostic tool for the diagnosis of desmoid tumors. This result has significant implications for patient care and management.
Carcinomas of unknown primary site are metastatic malignant epithelial tumours whose primary site cannot be identified during pretreatment assessment. They are characterised by their slow local development and their high metastatic potential. The primary site remains unknown in 20–50% of the patients, but the results from autopsies show that the primary tumours are most often located in the pancreas, lung, gut or kidney.
In France, the incidence of carcinomas of unknown primary site is eight out of 100 000 per year, corresponding to between 5 and 7% of the solid tumours in adults. The average age at detection is 60 years old, with slightly more men being affected. The median survival time is only a few months.
The heterogeneity of carcinoma of unknown primary site is due to the different histopathological types and anatomical localisations, making this a difficult topic to cover. In this document, we present the diagnostic strategy based on these two parameters, with the first entry point being the histopathological type. The therapeutic strategies to be used depend on the prognostic factors: specific anatomoclinical entities (neuroendocrine tumours, cervical lymph node metastases from squamous cell carcinoma, axillary lymph node metastases from an adenocarcinoma in women, undifferentiated carcinoma of the mediastinum in young men) and other nonspecific situations. Although primary papillary serous carcinoma is no longer included in the classification of peritoneum carcinomas of unknown primary site, we covered the management in women here in an attempt to be exhaustive.
PURPOSE: To identify most significant and therapeutically relevant prognostic factors in adults with localized primary synovial sarcomas (SS) and to confirm the usefulness of the French Federation of Cancer Centers (FNCLCC) grading system, the prognostic impact of which has been already proven in soft tissue sarcomas. PATIENTS AND METHODS: Data on 128 patients with nonmetastatic SS collected from a cooperative database by the FNCLCC Sarcoma Group between 1980 and 1994 were studied retrospectively. Immunohistochemistry was performed at diagnosis in 77 cases (61%). The tumors were classified as biphasic (n = 45), monophasic fibrous (n = 72), and poorly differentiated (n = 10) subtypes. Histologic grade was determined according to the FNCLCC method, and vascular invasion was assessed in every case. RESULTS: The 5-year disease-specific survival (DSS) rate for this series of patients with localized SS was 62.9% (± 9.6% [SD]) with a median follow-up time of 37 months (range, 8 to 141 months). In multivariate analysis, the adverse risk factors associated with decreased DSS were International Union Against Cancer/American Joint Committee on Cancer stage III/IVA disease, male sex, and truncal tumor locations. For metastasis-free survival (MFS), disease stage III/IVA, tumor necrosis, and monophasic subtypes were the major factors associated with a less favorable prognosis. Separately, when not using disease stage, tumor necrosis, and mitotic activity, histologic grade became the most significant prognostic factor for both DSS and MFS. In addition, larger tumors and older patients become associated with a significantly worse prognosis. Independent adverse risk factors for local recurrence–free survival included histologic grade 3 and truncal tumor location. CONCLUSION: These data confirm that not all SS present the same severe outcome. High-risk patients identified on the basis of these parameters may qualify for an aggressive treatment approach.
Abstract An immunohistological study of 15 chordomas, six chondrosarcomas, four liposarcomas and seven carcinomas on paraffin embedded samples using anti‐cytokeratin, anti‐epithelial membrane antigen (EMA), anti‐S100 protein, anti‐vimentin and anti‐neurofilaments showed that chordomas has a characteristic immuno‐staining, i.e. positive for cytokeratin, EMA, S100 protein and vimentin; and negative for neurofilaments. This immuno‐staining allows a clear distinction of chordomas from other tumours.
Abstract Genomic instability (GI) influences treatment efficacy and resistance, and an accurate measure of it is lacking. Current measures of GI are based on counts of specific structural variation (SV) and mutational signatures. Here, we present a holistic approach to measuring GI based on the quantification of the steady-state equilibrium between DNA damage and repair as assessed by the residual breakpoints (BP) remaining after repair, irrespective of SV type. We use the notion of Hscore, a BP “hotspotness” magnitude scale, to measure the propensity of genomic structural or functional DNA elements to break more than expected by chance. We then derived new measures of transcription- and replication-associated GI that we call iTRAC (transcription-associated chromosomal instability index) and iRACIN (replication-associated chromosomal instability index). We show that iTRAC and iRACIN are predictive of metastatic relapse in Leiomyosarcoma (LMS) and that they may be combined to form a new classifier called MAGIC (mixed transcription- and replication-associated genomic instability classifier). MAGIC outperforms the gold standards FNCLCC and CINSARC in stratifying metastatic risk in LMS. Furthermore, iTRAC stratifies chemotherapeutic response in LMS. We finally show that this approach is applicable to other cancers.
Background Since 2010, nationwide networks of reference centers for sarcomas (RREPS/NETSARC/RESOS) collected and prospectively reviewed all cases of sarcomas and connective tumors of intermediate malignancy (TIM) in France. Methods The nationwide incidence of sarcoma or TIM (2013–2016) was measured using the 2013 WHO classification and confirmed by a second independent review by expert pathologists. Simple clinical characteristics, yearly variations and correlation of incidence with published clinical trials are presented and analyzed. Results Over 150 different histological subtypes are reported from the 25172 patients with sarcomas (n = 18712, 74,3%) or TIM (n = 6460, 25.7%), with n = 5838, n = 6153, n = 6654, and n = 6527 yearly cases from 2013 to 2016. Over these 4 years, the yearly incidence of sarcomas and TIM was therefore 70.7 and 24.4 respectively, with a combined incidence of 95.1/10 6 /year, higher than previously reported. GIST, liposarcoma, leiomyosarcomas, undifferentiated sarcomas represented 13%, 13%, 11% and 11% of tumors. Only GIST, as a single entity had a yearly incidence above 10/10 6 /year. There were respectively 30, 64 and 66 different histological subtypes of sarcomas or TIM with an incidence ranging from 10 to 1/10 6 , 1–0.1/10 6 , or < 0.1/10 6 /year respectively. The 2 latter incidence groups represented 21% of the patients with 130 histotypes. Published phase III and phase II clinical trials (p<10 −6 ) are significantly higher with sarcomas subtypes with an incidence above 1/10 6 per. Conclusions This nationwide registry of sarcoma patients, with exhaustive histology review by sarcoma experts, shows that the incidence of sarcoma and TIM is higher than reported, and that tumors with a very low incidence (1<10 6 /year) are less likely to be included in clinical trials.
To assess the prognostic value of SYT-SSX fusion type, in comparison with other factors, in a population of 165 patients with synovial sarcoma (SS).Data on 165 patients with SS (141 with localized disease at diagnosis) were studied retrospectively. The following parameters were examined for their potential prognostic value: age at diagnosis, sex, tumor site (extremities v proximal/truncal), size, histology, mitotic count, necrosis, histologic grade (Federation Nationale des Centres de Lutte Contre le Cancer system), stage (1997 tumor-node-metastasis system classification), surgical margin status (assessed histologically), and fusion type (SYT-SSX1 v SYT-SSX2). Median follow-up time was 37 months (range, 2 to 302 months).Among those patients with localized disease at diagnosis, median and 5-year disease-specific survivals (DSS) for the SYT-SSX1 and SYT-SSX2 subgroups were 126 months and 67.4% versus 82 months and 63.2%, respectively (P = .12). Median and 5-year metastasis-free survivals (MFS) were 84 months and 54.2% for SYT-SSX1 versus 50 months and 47.6% for SYT-SSX2 (P = .76). Univariate analyses showed that high histologic grade (grade 3), high mitotic count (>/= 10 mitoses/10 high-power fields), stage III disease, size greater than 7 cm, tumor necrosis, and presence of areas of poorly differentiated morphology were significant adverse prognostic factors for DSS and MFS, whereas SYT-SSX fusion type, tumor histology (biphasic v monophasic), and patient sex were not. Age greater than 35 years adversely affected DSS but not MFS. In multivariate analyses, histologic grade was the most significant prognostic factor for both DSS and MFS.For patients with localized SS, histologic grade but not SYT-SSX fusion type is a strong predictor of survival.
