Epidemiological profile of soft tissue sarcomas of the extremities: Incidence, histological subtypes, and primary sites.

BACKGROUND: Soft tissue sarcomas (STS) are a heterogeneous group of rare tumours that represent less than 1% of all malignant, solid tumours in adults. There is limited epidemiological information regarding STS in Latin America. Therefore, the objective of this study is to present an epidemiological profile of these tumours observed at a single reference centre. METHODS: A retrospective study was carried out based on hospital records obtained from a registry of 879 patients with STS of the extremities who were treated at the National Cancer Institute of Mexico from January 1, 1994 to December 31, 2017. Epidemiological variables and relevant clinical data were collected. Five-year survival rates were analysed using Kaplan-Meier estimates, and a multivariate Cox proportional-hazards model measured associations. RESULTS: A total of 879 records were collected. The median age was 45 years (15-95 years), and the ratio of men to women was 1:1, with 433 men (49.3%), and 446 women (50.7%). The median tumour size was 11.4 cm (2-49 cm). The most prevalent histological variants were liposarcomas and synovial sarcomas. The lower limb was the most frequently affected extremity, with the thigh being the most common site followed by the leg. A majority of the patients were diagnosed at clinical stages IIIA-IV. CONCLUSIONS: The data collected from the present cohort provides an overview of the epidemiological profile of STS at a single reference centre in Latin America, and allow comparison with global data.

Should metastatic lymph nodes be considered at the same clinical stage as distant metastasis in soft tissue sarcomas?

INTRODUCTION: Lymph node metastasis (LNM) in soft tissue sarcomas (STS) are uncommon, occurring in only 3% - 5% of all sarcomas, and are classified as Stage IV, along with distant metastasis (DM). This paper compares the prognosis of patients with lymphatic and DM, in extremity STS (eSTS). METHODS: A retrospective study was carried out in a high-volume sarcoma center; 853 patients with eSTS sarcomas were identified and classified from January 1, 1997 to December 31, 2017. Cases with pathological confirmation of LNM were included. Five-year survival rates were analyzed using the Kaplan-Meier method and the Cox proportional hazards model. RESULTS: LNM was present in 46 of the cases (5.4%), with an overall survival of 21 months (95% confidence interval [CI], 16.7 - 25.2), compared to 18 months (95% confidence interval [CI], 14.2 - 21.7) in those with only DM. Median recurrence-free survival was 21 months (95% confidence interval [CI], 19.7 - 22.4), vs. 20 months (95% confidence interval [CI], 16.2- 23.7), respectively. LNM only and DM only had also a similar OS of 21 months (95% CI 16.7-25.2) vs 18 months (95% CI 14.2-21.7. N1M1 cases had the worse median OS with 15 months (95% confidence interval [CI], 10.9-19.7) CONCLUSIONS: Overall survival and recurrence free survival in patients with lymph node disease and metastatic disease are similar. However prognosis is worse in N1M1. Use of systemic treatment in patients with LNM is not as common as in metastatic cases, this difference in treatment and the fact that prognosis is similar suggests that both biological behavior and effect of treatment have been underestimated. A subclassification of clinical stage IV might be the next step.

Desmoid-Type Fibromatosis.

Desmoid tumors represent a rare entity of monoclonal origin characterized by locally aggressive behavior and inability to metastasize. Most cases present in a sporadic pattern and are characterized by a mutation in the CTNNB1 gene; while 5-15% show a hereditary pattern associated with APC gene mutation, both resulting in abnormal ß-catenin accumulation within the cell. The most common sites of presentation are the extremities and the thoracic wall, whereas FAP associated cases present intra-abdominally or in the abdominal wall. Histopathological diagnosis is mandatory, and evaluation is guided with imaging studies ranging from ultrasound, computed tomography or magnetic resonance. Current approaches advocate for an initial active surveillance period due to the stabilization and even regression capacity of desmoid tumors. For progressive, symptomatic, or disabling cases, systemic treatment, radiotherapy or surgery may be used. This is a narrative review of this uncommon disease; we present current knowledge about molecular pathogenesis, diagnosis and treatment.

[An elderly female with abdominal pain]. / Mujer de 78 años de edad con dolor abdominal severo.

A case of a 78-year-old female who presented with clinical, ultrasonographic and laboratory findings typical of acute cholecystitis is presented. Diagnostic laparoscopy revealed a hemorrhagic infrahepatic mass and free blood within the peritoneal space; the procedure was then converted to an open one, which identified a 15 x 5 cm mass corresponding to a gallbladder volvulus. The final histopathologic study confirmed the diagnosis. A gallbladder volvulus should be suspected in elderly patients, particularly in those with a previous history of significant weight loss, who additionally present positive clinical and paraclinical data of acute cholecystitis. There are no still biochemical exams that may preoperatively identify patients at high risk for this infrequent abnormality.