Real world evidence of adjuvant trastuzumab in HER2 positive early breast cancer.

Adjuvant trastuzumab in HER2+ breast cancer reduces recurrence and mortality, and has been the standard treatment since 2006. The objective was to analyze health outcomes in the real world. Observational, retrospective study of patients with HER2+ breast cancer, stages I-III, treated with adjuvant trastuzumab in the past 15 years in only one center and for the first time in Spain. Survival was analyzed according to the number of cycles and cardiotoxicity. Two hundred and seventy-five HER2positive patients (18.60%) out of 1479 received adjuvant (73%) or neoadjuvant/adjuvant (26%) trastuzumab, concomitantly (90%) or sequentially (10%) with chemotherapy. The probability of overall and disease-free survival (OS and DFS) at 5 years was 0.93 (95% CI 0.89-0.96), and 0.88 (95% CI 0.83-0.92). The number of cases with a significant and asymptomatic decrease in ventricular ejection fraction and heart failure were 54 (19.64%) and 12 (4.36%), respectively. Sixty-eight patients (24.70%) received 16 or fewer cycles, especially those older than 65 (OR 0.371, 95% CI 0.152-0.903; p = 0.029) and with cardiotoxicity (OR 15.02, 95% CI 7.437-30.335; p < 0.001). The risk of cardiotoxicity was associated with having received radiotherapy (OR 0.0362, 95% CI 0.139-0.938; p = 0.037). Arterial hypertension (HR 0.361, 95% CI 0.151-0.863, p = 0.022), neoadjuvant treatment (HR 0.314, 95% CI 0.132-0.750, p = 0.009) and cardiotoxicity (HR 2.755, 95% CI 1.235-6.143, p = 0.013) maintained significant association with OS. Only neoadjuvant treatment maintained a significant association with DFS (HR 0.437, 95% CI 0.213-0.899, p = 0.024). The effectiveness of neoadjuvant and adjuvant trastuzumab can be considered comparable to those of clinical trials. In the real world, factors such as age, hypertension, radiotherapy, neoadjuvant treatment, and cardiotoxicity should be taken into consideration to optimize outcomes.

Real-world data of fulvestrant as first-line treatment of postmenopausal women with estrogen receptor-positive metastatic breast cancer.

Goals of endocrine therapy for advanced breast cancer (ABC) include prolonging survival rates, maintaining the quality of life, and delaying the initiation of chemotherapy. We evaluated the effectiveness of fulvestrant as first-line in patients with estrogen receptor (ER)-positive ABC with relapse during or after adjuvant anti-estrogenic therapy in real-world settings. Retrospective, observational study involving 171 postmenopausal women with ER-positive ABC who received fulvestrant as first-line between January 2011 and May 2018 in Spanish hospitals. With a median follow-up of 31.4 months, the progression-free survival (PFS) with fulvestrant was 14.6 months. No differences were seen in the visceral metastatic (14.3 months) versus non-visceral (14.6 months) metastatic subgroup for PFS. Overall response rate and clinical benefit rate were 35.2% and 82.8%. Overall survival was 43.1 months. The duration of the clinical benefit was 19.2 months. Patients with ECOG performance status 0 at the start of treatment showed a significant greater clinical benefit rate and overall survival than with ECOG 1-2. Results in real-world settings are in concordance with randomized clinical trials. Fulvestrant continues to demonstrate clinical benefits in real-world settings and appears be well tolerated as first-line for the treatment of postmenopausal women with ER-positive ABC.

Correction to: Efficacy of fulvestrant in the treatment of postmenopausal women with endocrine-resistant advanced breast cancer in routine clinical practice.

A sentence under 'Results' heading in the Abstract section was published incorrectly. The correct sentence should read as follows.

Evaluation of waiting times for breast cancer diagnosis and surgical treatment.

PURPOSE: To analyse any delays in breast cancer diagnosis and surgical treatment, influence of clinical and biological factors and influence of delays on survival. METHODS/PATIENTS: A descriptive, observational, and retrospective study was conducted between 2006 and 2016 on stages I-III breast cancer patients. This is a retrospective review of health records to collect data on delays, patients' clinical data, biological features of the tumour and information on treatment. Mortality data from the National Death Index. RESULTS: In 493 evaluable patients, the median of days from the first symptom to mammography, biopsy, and surgery was 41, 57, and 92, respectively. The median of days from screening mammography to biopsy and surgery was 10 and 51, respectively. From biopsy to surgery, the median was 34 days in every case. Over the last 5 years, an increase in biopsy-surgery delay has been observed (p = 0.0001). Tumour stages I and II vs. stage III (RR 1.74. 95% CI 1.08-2.80, p = 0.027), diagnosis in screening (RR 0.66. 95% CI 0.45-0.96, p = 0.030), and use of magnetic resonance imaging (RR 2.08. 95 CI 1.21-3.56, p = 0.008) condition a greater biopsy-surgery delay. No influence of delays on survival has been identified. CONCLUSIONS: Delays in diagnosis and surgery in the case of women diagnosed on the basis of symptoms may be improved. There is a temporary tendency to a greater delay in surgery. Some clinical and biological factors must be taken into account to optimise delays. Survival results are not adversely affected by delays.

Efficacy of fulvestrant in the treatment of postmenopausal women with endocrine-resistant advanced breast cancer in routine clinical practice.

INTRODUCTION: This study aimed to describe the efficacy of fulvestrant 500 mg in postmenopausal women with estrogen receptor (ER)-positive advanced/metastatic breast cancer who had disease progression after receiving anti-estrogen therapy in clinical practice, getting real-world data. MATERIALS AND METHODS: Multicenter, retrospective, observational study conducted in Spain. Postmenopausal women with locally advanced/metastatic ER-positive breast cancer who received treatment with fulvestrant 500 mg after progression with a previous anti-estrogen therapy were eligible. The primary endpoint was progression-free survival (PFS); secondary endpoints were overall survival (OS), clinical benefit rate (CBR), duration of clinical benefit (DoCB), and safety profile. RESULTS: A total of 263 women were evaluated (median age, 65.8 years). At a median follow-up of 21.5 months, median PFS and OS were 10.6 and 43.2 months, respectively. PFS according to 1st, 2nd, 3rd, and ≥ 4th lines were 11.5, 10.6, 9.9, and 8.5 months, respectively (p = 0.0245). PFS in patients with visceral involvement was 10 months vs 10.6 months in patients without visceral involvement (p = 0.6604), 9.6 months in patients with high Ki67 vs 10 months in patients with low Ki67 (p = 0.7224), and 10.2 months in HER2+ patients vs 10.3 months in HER2- patients (p = 0.6809). The CBR was 56.5% and the DoCB was 18.4 months. The most frequently adverse events were injection site pain (10.3%) and musculoskeletal disorders (7.6%). CONCLUSIONS: Fulvestrant 500 mg administered in clinical practice was shown to be effective (PFS, 10.6 months; CBR, 56.5%) and well tolerated, in accordance with previous trials.

Implementation of safeguards to improve patient safety in chemotherapy.

PURPOSE: To evaluate the effectiveness of safeguards introduced in the process of using cytostatic agents for increasing the safety of oncology patients. METHODS: Prospective hospital study conducted in two stages, before and after the implementation of safeguards: staff training, standardized procedures, computerized prescription, pharmaceutical validation, implementation of bar codes, and a new manual on drug interactions. Medication errors (MEs) were actively recorded during the process of administering chemotherapy in the Medical Oncology Department. The study classified MEs by the stage of the medication process in which they occurred and assessed their severity. RESULTS: 500 patients, 250 before implementing safeguards and 250 afterward, were included in this study . Out of all patients included before, 43.1% had at least 1 error, compared to 27% of those included later. The number of MEs detected before and after was 144 vs. 95: 125 vs. 55 prescription errors, 2 vs. 5 validation errors, 14 vs. 4 preparation errors, 3 vs. 1 dispensation errors and 0 vs. 30 administration errors. The number of MEs that reached the patient before and after safeguard implementation was 16.7% vs. 6.3%. After the safeguards were introduced, all MEs that could have caused harm or required monitoring of some kind were prevented. CONCLUSIONS: Implementing safeguards in the hospital's cytostatic treatment cycle is useful for preventing MEs. Computerized prescription, pharmaceutical validation, and the creation/dissemination of proper work procedures are effective barriers that keep MEs from reaching the patient. Administering chemotherapy with a bar-code system facilitates detection error detection at this stage of the cycle and prevents them from reaching the patient.

Spanish Mediterranean diet and other dietary patterns and breast cancer risk: case-control EpiGEICAM study.

BACKGROUND: Although there are solid findings regarding the detrimental effect of alcohol consumption, the existing evidence on the effect of other dietary factors on breast cancer (BC) risk is inconclusive. This study aimed to evaluate the association between dietary patterns and risk of BC in Spanish women, stratifying by menopausal status and tumour subtype, and to compare the results with those of Alternate Healthy Index (AHEI) and Alternate Mediterranean Diet Score (aMED). METHODS: We recruited 1017 incident BC cases and 1017 matched healthy controls of similar age (±5 years) without a history of BC. The association between 'a priori' and 'a posteriori' developed dietary patterns and BC in general and according to menopausal status and intrinsic tumour subtypes (ER+/PR+ and HER2-; HER2+; and ER-/PR- and HER2-) was evaluated using logistic and multinomial regression models. RESULTS: Adherence to the Western dietary pattern was related to higher risk of BC (OR for the top vs the bottom quartile 1.46 (95% CI 1.06-2.01)), especially in premenopausal women (OR=1.75; 95% CI 1.14-2.67). In contrast, the Mediterranean pattern was related to a lower risk (OR for the top quartile vs the bottom quartile 0.56 (95% CI 0.40-0.79)). Although the deleterious effect of the Western pattern was similarly observed in all tumour subtypes, the protective effect of our Mediterranean pattern was stronger for triple-negative tumours (OR=0.32; 95% CI 0.15-0.66 and Pheterogeneity=0.04). No association was found between adherence to the Prudent pattern and BC risk. The associations between 'a priori' indices and BC risk were less marked (OR for the top vs the bottom quartile of AHEI=0.69; 95% CI 0.51-0.94 and aMED=0.74; 95% CI 0.46-1.18)). CONCLUSIONS: Our results confirm the harmful effect of a Western diet on BC risk, and add new evidence on the benefits of a diet rich in fruits, vegetables, legumes, oily fish and vegetable oils for preventing all BC subtypes, and particularly triple-negative tumours.

Influencia de los factores clínicos y biográficos en la calidad de vida de las mujeres durante la quimioterapia adyuvante por cáncer de mama / Influence of clinic Hospital Universitario Puerta del Mar, Cádiz, Españaal and biographical factors on the quality of life of women with breast cancer receiving adjuvant chemotherapy

Objetivo. La quimioterapia adyuvante afecta a diferentes aspectos de la calidad de vida de la mujer con cáncer de mama. Se ha estudiado su efecto en la calidad de vida y el impacto de las variables clínicas y biográficas. Material y método. Una cohorte de mujeres con cáncer de mama, tratadas con quimioterapia adyuvante, participantes en un ensayo clínico aleatorizado de intervención no farmacológica (ClinicalTrials.gov Identifier: NCT00964522), completó los cuestionarios de calidad de vida EORTC QOL-C30 y QOL-BR23 antes, a mitad y al terminar el tratamiento. Resultados. Cincuenta mujeres completaron los cuestionarios. La salud global empeoró con el tiempo (p=0,01). El funcionamiento físico (p=0,0001) y la imagen corporal (p=0,002) fueron las escalas más deterioradas. La astenia (p=0,004), las náuseas y vómitos (p=0,05) y anorexia (p=0,025) fueron los síntomas con mayor efecto temporal de la quimioterapia. Las mujeres desempleadas sufrieron peor funcionamiento físico (p=0,046) y de rol (p=0,005). Las mayores presentaron más diarrea (p=0,013). Las más educadas mostraron peor puntuación en la escala de dificultades financieras (p=0,034). Los casos con estadios más avanzados sufrieron mayor deterioro en su imagen corporal (p=0,001) y estuvieron más preocupados por su futuro (p=0,006). Las tratadas con antraciclinas y taxanos sintieron también peor perspectiva de futuro (p=0,02). Conclusiones. La quimioterapia adyuvante deteriora la calidad de vida de mujeres con cáncer de mama, sobre todo en su funcionamiento físico e imagen corporal. La astenia y toxicidad digestiva son los efectos secundarios predominantes. Las mujeres necesitan soporte si son mayores, desempleadas, mejor formadas, con estadio III y tratadas con antraciclinas y taxanos(AU)

Objective. Adjuvant chemotherapy affects the life of women with breast cancer in different ways. The aim of this work is to study the effect of adjuvant chemotherapy on the quality of their lives and the impact of their clinical and biographical characteristics. Patients and method. Women with breast cancer, candidates for adjuvant chemotherapy, participating in a randomised trial with non-pharmacological intervention (ClinicalTrials.gov Identifier: NCT00964522), completed the EORTC QOL-C30 and QOL-BR23 quality of life questionnaires before, in the middle, and at the end of the treatment. Results. Fifty women completed the questionnaires. Overall health got worse over time (p=0.01). Physical functioning (p=0.0001) and body image (p=0.002) were the scales that deteriorated most, and asthenia (p=0.004), nausea/vomiting (p=0.05), and anorexia (p=0.025), were the symptoms with the largest temporary impact of the chemotherapy. Unemployed women had worse physical functioning (p=0.046) and role functioning (p=0.005). Older women had more diarrhoea (p=0.013). The most qualified women had a worse score in financial difficulties scale (p=0.034). Women with advanced stage (III) underwent more deterioration in the body image (p=0.001) and were more concerned about the future (p=0.006). Women treated with anthracycline and taxane also had a worse perspective of the future (p=0.02). Conclusions. Adjuvant chemotherapy deteriorates the quality of life of patients with breast cancer, basically in physical functioning and body image areas. Asthenia and gastrointestinal toxicity are the side effects that affect patients most. Women need support if they are older, unemployed, more educated, and have stage III breast cancer treated with anthracycline and taxane based chemotherapy(AU)

[Influence of clinical and biographical factors on the quality of life of women with breast cancer receiving adjuvant chemotherapy]. / Influencia de los factores clínicos y biográficos en la calidad de vida de las mujeres durante la quimioterapia adyuvante por cáncer de mama.

OBJECTIVE: Adjuvant chemotherapy affects the life of women with breast cancer in different ways. The aim of this work is to study the effect of adjuvant chemotherapy on the quality of their lives and the impact of their clinical and biographical characteristics. PATIENTS AND METHOD: Women with breast cancer, candidates for adjuvant chemotherapy, participating in a randomised trial with non-pharmacological intervention (ClinicalTrials.gov Identifier: NCT00964522), completed the EORTC QOL-C30 and QOL-BR23 quality of life questionnaires before, in the middle, and at the end of the treatment. RESULTS: Fifty women completed the questionnaires. Overall health got worse over time (p=0.01). Physical functioning (p=0.0001) and body image (p=0.002) were the scales that deteriorated most, and asthenia (p=0.004), nausea/vomiting (p=0.05), and anorexia (p=0.025), were the symptoms with the largest temporary impact of the chemotherapy. Unemployed women had worse physical functioning (p=0.046) and role functioning (p=0.005). Older women had more diarrhoea (p=0.013). The most qualified women had a worse score in financial difficulties scale (p=0.034). Women with advanced stage (III) underwent more deterioration in the body image (p=0.001) and were more concerned about the future (p=0.006). Women treated with anthracycline and taxane also had a worse perspective of the future (p=0.02). CONCLUSIONS: Adjuvant chemotherapy deteriorates the quality of life of patients with breast cancer, basically in physical functioning and body image areas. Asthenia and gastrointestinal toxicity are the side effects that affect patients most. Women need support if they are older, unemployed, more educated, and have stage III breast cancer treated with anthracycline and taxane based chemotherapy.

Pegylated liposomal doxorubicin in combination with cyclophosphamide and trastuzumab in HER2-positive metastatic breast cancer patients: efficacy and cardiac safety from the GEICAM/2004-05 study.

BACKGROUND: In order to determine the feasibility of substituting pegylated liposomal doxorubicin (PLD) for doxorubicin in combination with cyclophosphamide and trastuzumab as adjuvant therapy, we conducted a phase II study of the combination as first-line therapy in human epidermal growth factor receptor 2 (HER2) overexpressing metastatic breast cancer (MBC). METHODS: PLD 50 mg/m(2) and cyclophosphamide 600 mg/m(2) were administered every 4 weeks for six cycles; trastuzumab (4 mg/kg loading dose, then 2 mg/kg) was administered weekly for 24 weeks. The primary end point was objective response rate (ORR), and the secondary end points included time to progression (TTP), overall survival (OS), and safety. RESULTS: Among the 48 evaluable patients, ORR was 68.8% [95% confidence interval (CI) 55.69% to 81.91%], with 6 patients (12.5%) achieving a complete response and 27 (56.2%) a partial response. The median TTP was 12 months (95% CI 9-15.1 months), and the median OS was 34.2 months (95% CI 27.2-41.2 months). Febrile neutropenia was seen in three patients, grade 3 hand-foot syndrome in 29.2% of patients, and grade 3-4 mucositis in 22.9% of patients. Symptomatic congestive heart failure was not observed, and 16.7% of patients experienced grade 2 asymptomatic left ventricular systolic dysfunction. CONCLUSION: The combination of PLD-cyclophosphamide-concurrent trastuzumab is a feasible, safe, and effective first-line regimen for HER2-overexpressing MBC.

Experiencia con un formato simplificado de la herramienta de ayuda en la toma de decisiones Adjuvant Online en pacientes con cáncer de mama / Experience with a simplified format of decision making tool adjuvant Online in breast cancer patients

Fundamento. Adjuvant. Online calcula el riesgo de recidiva y muerte a 10 años y proporciona estimaciones del beneficio del tratamiento adyuvante en pacientes con cáncer de mama. Testamos su aplicabilidad y analizamos únicamente estimaciones de mortalidad. Método. Presentamos las estimaciones de 66 pacientes intervenidas de cáncer de mama unilateral y unicéntrico, sin enfermedad residual ni metástasis. Las variables analizadas fueron edad, comorbilidad, receptores de estrógenos, grado histológico, tamaño tumoral, ganglios metastásicos, tipo de tratamiento hormonal y de quimioterapia. Resultados. La estimación de la mediana de supervivencia fue del 77%, de mortalidad por cáncer fue del 18% y por otras causas fue del 5%. La media de reducción absoluta del riesgo (RAR) de mortalidad con tratamiento hormonal fue del 4%, con quimioterapia fue del 4,5% y con tratamiento combinado fue del 7%. Resultados. Todas las pacientes con algún beneficio decidieron recibir tratamiento hormonal. Cuarenta y tres pacientes (65%) decidieron recibir quimioterapia y 23 pacientes (35%) decidieron no recibirla. La media de reducción del riesgo con quimioterapia fue del 2% en quien decidió no recibir quimioterapia y fue del 8% en quien decidió recibirla. Existe asociación entre la decisión de quimioterapia y la estimación del riesgo de mortalidad por cáncer (p=0,0001), del riesgo de mortalidad por otras causas (p=0,038) y de la RAR (p=0,0001). El 6% de las pacientes con RAR del 1%, el 50% de las que tenían RAR entre el 2–5%, y el 61,8% con RAR entre el 6–10% eligieron la quimioterapia. Conclusiones. Todas las mujeres optan por el tratamiento hormonal independientemente del beneficio. Las razones para elegir la quimioterapia fueron el propio pronóstico vital y la magnitud del beneficio. Algunas pacientes deciden elegir quimioterapia con beneficios mínimos(AU)

Background. Adjuvant. Online estimates 10-year recurrence and mortality outcomes for breast cancer patients and predicts the effect of each type of treatment. Our purpose was to test the applicability by only analysing mortality estimations. Method. We present estimations of 66 women with definitive surgery and axillary staging for unilateral, unicentric, invasive adenocarcinoma, without metastatic or residual disease. Age, co-morbidity, estrogen receptor status, histological grade, tumor size, number of positive nodes, and hormone therapy or chemotherapy option, were the variables required. Results. Median of survival estimations was 77%, cancer mortality 18% and mortality for other reasons 5%. The average of absolute risk reduction (ARR) with hormone therapy was 4%, with chemotherapy 4.5% and with combined treatment 7%. Results. All the patients with some benefit decided to receive hormone therapy. Forty-three patients (65%) decided to receive chemotherapy and 23 (35%) did not. The average risk reduction with chemotherapy was 2% in those who decided not to receive chemotherapy and 8% in those who decided to receive it. There was an association between a chemotherapy decision and the estimation of the risk of breast cancer mortality (P=0.0001), risk of mortality for other reasons (P=0.038), and the ARR (P=0.0001). There were 6% of the patients with an ARR of 1%, 50% between 2–5% and 61.8% between 6–10%, who chose chemotherapy. Conclusions. All women opted for hormone therapy regardless of benefit. The reasons for choosing chemotherapy were the prognosis itself and the magnitude of benefit. Some patients decided to choose chemotherapy even when the benefit was minimal(AU)

[Analysis of the effectiveness of an antiemetic protocol used in an oncology division]. / Análisis de la efectividad de un protocolo de antiemesis implantado en la Unidad de Oncología.

OBJECTIVE: To analyse the effectiveness of an antiemetic protocol in patients receiving chemotherapy treatment. METHOD: Prospective study in patients with solid tumours receiving chemotherapy in an oncology day hospital between January 2006 and 2007. We conducted a literature review and an evaluation of the recommendations of different clinical practice guidelines. The emetogenic potential was calculated according to the Hesketh level (HL), and the antiemetic premedication was determined for each regimen. We evaluated the effectiveness of an antiemetic protocol by using a survey as a method for measuring emetic episodes and nausea in the acute and delayed phases. RESULTS: 172 patients completed the survey. 13.4% vomited in the acute phase and 16.9% in the delayed phase; the median number of times was 2 (1-8) and 1 (1-5) for each respective phase. With treatment regimens classed as HL 4-5, 18.5% experienced vomiting in the acute phase and 20.2% in the delayed phase, with 46% experiencing nausea in the acute phase and 38.4% in the delayed phase. Control of vomiting in patients with treatment regimens classed as HL 1-3 was 100% in acute phase and 91.7% in the delayed phase; nausea was reported by 27% in the acute phase and 31% in the delayed phase. The factors that contributed the most to the presence of vomiting and nausea were the emetogenic potential of the treatment regimen (p<0.05), vomiting in the previous cycle (p<0.05) and age younger than 50 years (p<0.002). DISCUSSION: The proposed antiemetic protocol is effective for controlling vomiting in chemotherapy regimens with an HL of 1-3. For highly emetogenic regimens, the antiemetic protocol is also effective, but protection is not complete. This protocol seems less effective for controlling nausea, although this is a subjective symptom which is difficult to assess and not routinely measured in clinical trials.

[Experience with a simplified format of decision making tool adjuvant! Online in breast cancer patients]. / Experiencia con un formato simplificado de la herramienta de ayuda en la toma de decisiones Adjuvant! Online en pacientes con cáncer de mama.

BACKGROUND: Adjuvant! Online estimates 10-year recurrence and mortality outcomes for breast cancer patients and predicts the effect of each type of treatment. Our purpose was to test the applicability by only analysing mortality estimations. METHOD: We present estimations of 66 women with definitive surgery and axillary staging for unilateral, unicentric, invasive adenocarcinoma, without metastatic or residual disease. Age, co-morbidity, estrogen receptor status, histological grade, tumor size, number of positive nodes, and hormone therapy or chemotherapy option, were the variables required. RESULTS: Median of survival estimations was 77%, cancer mortality 18% and mortality for other reasons 5%. The average of absolute risk reduction (ARR) with hormone therapy was 4%, with chemotherapy 4.5% and with combined treatment 7%. All the patients with some benefit decided to receive hormone therapy. Forty-three patients (65%) decided to receive chemotherapy and 23 (35%) did not. The average risk reduction with chemotherapy was 2% in those who decided not to receive chemotherapy and 8% in those who decided to receive it. There was an association between a chemotherapy decision and the estimation of the risk of breast cancer mortality (P=0.0001), risk of mortality for other reasons (P=0.038), and the ARR (P=0.0001). There were 6% of the patients with an ARR of 1%, 50% between 2-5% and 61.8% between 6-10%, who chose chemotherapy. CONCLUSIONS: All women opted for hormone therapy regardless of benefit. The reasons for choosing chemotherapy were the prognosis itself and the magnitude of benefit. Some patients decided to choose chemotherapy even when the benefit was minimal.

GIST: a propósito de un término confuso y presentación de un caso de tumor del estroma extragastrointestinal / GIST: about a confused term, and presentation of a case of extra-gastrointestinal stromal tumor

Propósito: El GIST es un tumor pertenecientea los sarcomas de partes blandas y aunque su localizaciónmás frecuente es el tracto gastrointestinal seha descrito fuera de ésta a pesar de lo cual persisteesa denominación, lo que es, en bastantes casos,motivo de confusión.Material y métodos: Se presenta el caso deun varón de 57 años diagnosticado, en principio, de“tumor de músculo liso de potencial maligno incierto”en base a su localización retroperitoneal. Tras larevisión y determinación de c-kit (CD-117), se hizoel diagnóstico definitivo de “tumor estromal de localizaciónretroperitoneal”.Conclusiones: Proponemos el término menosconfuso de “tumor estromal con fenotipo de célulasintersticiales de Cajal”

Purpose: GIST is a soft tissue sarcoma withpreferential location for the gastrointestinal tract.However, it has been described in extragastrointestinaltissues. The persistence of the denominationmay eventually lead to confusion, because theabbreviation refers to the gastrointestinal tractMaterial and methods: We present the caseof a 57 year old man with initial diagnosis ofsuffering from a “smooth muscle tumor with uncertainmalignant potential”, based on its retroperitoneallocation. After medical examination and c-kit(CD-117) determination, the definitive diagnosis of“stromal tumor of retroperitoneal location” was made.Conclusions: We propose the term “stromaltumor with Cajal’s interstitial cells phenotype”