Osteosarcoma de alto grado originado en un tumor filodes maligno / High grade osteosarcoma originated in a malignant phyllodes tumor

Resumen El tumor filodes maligno con componente estromal (sic) de osteosarcoma es un tumor de muy baja incidencia. La identificación de esta enfermedad se ha convertido en un desafío para la medicina actual debido a su difícil diagnóstico histopatológico, imagenológico y clínico. El tratamiento principal se basa en el manejo quirúrgico y las opciones de terapia adyuvante aún no presentan un sustento científico sólido para su utilización como tratamiento estándar. Su pronóstico no es bueno y la variante osteoblástica presenta un comportamiento muy agresivo, con un riesgo del 38% para compromiso metastásico y riesgo de muerte debido a la enfermedad del 33%. Se presenta el caso de una paciente y se describe cómo se diagnosticó y se trató la enfermedad.

Abstract Malignant phyllodes tumor with osteosarcomatous differentiation has a very low incidence. The assessment of this tumor has become a challenge for current medicine due to its difficult histopathological, imaging and clinical diagnosis. The main treatment is based on surgical management, and the options of adjuvant therapy have not yet presented a solid evidence for its use as standard of care. Its prognosis is not good. The osteoblastic subtype, especially, has a very aggressive behavior, with a risk of 38 % for metastatic compromise and risk of death due to pathology of 33 %. We present the case of a patient and describe how the disease was diagnosed and treated.

Pathological Response to Neoadjuvant Chemotherapy and the Molecular Classification of Locally Advanced Breast Cancer in a Latin American Cohort.

BACKGROUND: The majority of patients with breast cancer in Colombia are admitted into oncological centers at locally advanced stages of the disease (53.9%). The aim of this study was to describe the pathological response obtained with neoadjuvant chemotherapy (NACT) according to the molecular classification of breast cancer in patients with locally advanced tumors treated within the National Cancer Institute (NCI) Functional Breast Cancer Unit (FBCU) in Bogotá, Colombia. MATERIALS AND METHODS: This was an observational, descriptive, historical cohort study of patients with locally advanced breast cancer treated within the NCI FBCU. RESULTS: We included 414 patients who received NACT and surgical management. Most patients had luminal B HER2-negative tumors (n = 134, 32.4%). The overall rate of pathological complete response (pCR) ypT0/ypN0 was 15.2% (n = 63). Tumors that presented the highest rate of pCR were pure HER2, at 40.5% (n = 15; odds ratio [OR], 6.7); however, with a follow-up of 60 months, only the triple negative tumors presented a statistically significant difference for event-free survival (EFS; median recurrence time, 18 months; range, 1-46) and overall survival (OS; median follow-up, 31 months; range 10-57). The molecular subtype that most recurrences presented was luminal B HER2 negative, at 38.3% (n = 28). The majority of recurrences (93.2 %; n = 68; OR, 5.9) occurred in patients in whom no pathological response was obtained (Chevallier 3 and 4). CONCLUSION: Pathological response in locally advanced tumors is related to the molecular subtype of breast cancer, finding higher pCR rates in pure HER2 and triple-negative tumors. A direct relationship was found between disease recurrences and the pathological response, evidencing greater tumor recurrence in patients who did not respond to NACT (Chevallier 3 and 4). EFS and OS were greater in patients with pCR, with statistical significance only in triple-negative tumors. IMPLICATIONS FOR PRACTICE: This research article is of scientific interest, because it describes the clinical and pathological features and analyzes the correlation between pathological response to neoadjuvant chemotherapy and the molecular classification of locally advanced breast cancer in patients treated in the National Cancer Institute in Bogotá, Colombia. It was found that pathological response is related to the molecular subtype of breast cancer. In addition, there is a direct relationship between disease recurrences and pathological response. The survival results were greater in patients with pathological complete response.