F.J. Pena Pardo

Gammagrafía ósea en la enfermedad de Erdheim-Chester

Resumen.— La enfermedad de Erdheim-Chester (EEC) es una enfermedad rara, con menos de 80 casos publicados en el mundo. Consiste en una histiocitosis de celulas no Langerhans que se manifiesta habitualmente en forma de dolor, por compromiso oseo, aunque es la afectacion extraosea la que marca el pronostico. Aunque el diagnostico definitivo precisa un estudio anatomopatologico (habitualmente a traves de una biopsia osea), los hallazgos radiologicos, y tambien los gammagraficos, son quasi-patognomonicos.En este trabajo presentamos 2 casos de EEC y sus respectivas gammagrafias oseas. Ambos muestran los hallazgos tipicos descritos en la literatura. Observamos hipercaptaciones bilaterales simetricas en las diafisis y metafisis de los huesos largos, fundamentalmente en las extremidades inferiores, estando respetadas las epifisis (en el primer caso solo parcialmente) y el tercio medio de las diafisis, asi como el esqueleto axial. PALABRAS CLAVE: Enfermedad de Erdheim-Chester. Gammagrafia osea. Histiocitosis. BONE SCINTIGRAPHY IN ERDHEIM-CHESTER DISEASE Summary.— Erdheim-Chester disease (ECD) is a rare disorder with fewer than 80 cases reported in the world. It consists of a non-Langerhans’ cell histiocytosis that usually presents as pain due to bone involvement; however, the prognosis is marked by extraskeletal involvement. Although the final diagnosis needs an anatomophatologic study (normally through a bone biopsy), radiologic and scintigraphic findings are quasi pathognomonic. In this work, we report 2 ECD cases and their respective bone scans showing typical findings described in the literature. We found bilateral and symmetrical increased uptake of diaphyses and metaphyses of long bones, mainly in lower limbs. The mid-diaphyses and the epiphyses (partially in the first case) as well as the axial skeleton are spared.

Solitary focus in the liver in a thyroid cancer patient after a whole body scan with 131 iodine.

A 51-year-old woman diagnosed with follicular variant of papillary thyroid carcinoma underwent a total thyroidectomy followed four weeks later by an ablative dose of 3.7 GBq of 131I. A whole body scan 5 days after ablation showed an intense uptake within the thyroid bed and a focal uptake located in the right lung base or liver dome. Computed tomography examination revealed a hypodense hepatic node in segment VII resembling a liver metastasis. Histological examination after ultrasound-guided fine-needle aspiration characterized the lesion as a liver abscess. The abscess regressed after antibiotic therapy. Liver metastases from papillary thyroid carcinoma are uncommon. On the other hand, false positive findings of 131I whole body scans have been described. A focal hepatic uptake might represent a metastasis (rare in papillary carcinomas) or be related to other causes (cysts, inflammation or infection, non-thyroidal neoplasms, etc.).

Papel predictivo y pronóstico de las variables volumétricas metabólicas obtenidas en la 18F-FDG PET/TC en el cáncer de mama con indicación de quimioterapia neoadyuvante

espanolObjetivo Investigar la utilidad de las variables metabolicas obtenidas en la 18F-FDG PET/TC en la prediccion de la respuesta a quimioterapia neoadyuvante (QNA) y el pronostico en el cancer de mama locamente avanzado (CMLA). Material y metodos Estudio prospectivo que incluye a 67 pacientes con CMLA, indicacion de QNA y 18F-FDG PET/TC basal. Se obtuvieron las variables SUV (SUVmax, SUVmedio y SUVpico) y volumetricas, tales como el volumen tumoral metabolico (VTM) y la glucolisis total lesional (GTL). Los tumores se agruparon en fenotipos moleculares y fueron clasificadas como respondedores y no respondedores tras la finalizacion de la QNA. Se obtuvo el estado libre de enfermedad (eLE), supervivencia libre de enfermedad (SLE) y supervivencia global (SG). Se realizo analisis univariante y multivariante para estudiar el potencial de todas las variables en la prediccion de la eLE, SLE y SG. Resultados Catorce pacientes se clasificaron como respondedoras. La media ± DE de la SLE y de la SG fue de 43 ± 15 y 46 ± 13 meses, respectivamente. El SUV y la GTL mostraron una relacion significativa (p Conclusion Las variables metabolicas obtenidas con la 18F-FDG PET/TC, de forma distinta a las variables de SUV, fueron buenos predictores tanto de la respuesta al tratamiento quimioterapico neoadyuvante y el pronostico. EnglishAim To investigate the usefulness of metabolic variables using 18F-FDG PET/CT in the prediction of neoadjuvant chemotherapy (NC) response and the prognosis in locally advanced breast cancer (LABC). Material and methods Prospective study including 67 patients with LABC, NC indication and a baseline 18F-FDG PET/CT. After breast tumor segmentation, SUV variables (SUVmax, SUVmean and SUVpeak) and volume-based variables, such as metabolic tumor volume (MTV) and total lesion glycolysis (TLG), were obtained. Tumors were grouped into molecular phenotypes, and classified as responders or non-responders after completion of NC. Disease-free status (DFs), disease-free survival (DFS), and overall survival (OS) were assessed. A univariate and multivariate analysis was performed to study the potential of all variables to predict DFs, DFS, and OS. Results Fourteen patients were classified as responders. Median ± SD of DFS and OS was 43 ± 15 and 46 ± 13 months, respectively. SUV and TLG showed a significant correlation (p Conclusion Volume-based metabolic variables obtained with 18F-FDG PET/CT, unlike SUV based variables, were good predictors of both neoadjuvant chemotherapy response and prognosis.AIM To investigate the usefulness of metabolic variables using 18F-FDG PET/CT in the prediction of neoadjuvant chemotherapy (NC) response and the prognosis in locally advanced breast cancer (LABC). MATERIAL AND METHODS Prospective study including 67 patients with LABC, NC indication and a baseline 18F-FDG PET/CT. After breast tumor segmentation, SUV variables (SUVmax, SUVmean and SUVpeak) and volume-based variables, such as metabolic tumor volume (MTV) and total lesion glycolysis (TLG), were obtained. Tumors were grouped into molecular phenotypes, and classified as responders or non-responders after completion of NC. Disease-free status (DFs), disease-free survival (DFS), and overall survival (OS) were assessed. A univariate and multivariate analysis was performed to study the potential of all variables to predict DFs, DFS, and OS. RESULTS Fourteen patients were classified as responders. Median±SD of DFS and OS was 43±15 and 46±13 months, respectively. SUV and TLG showed a significant correlation (p<0.005) with the histological response, with higher values in responders compared to non-responders. MTV and TLG showed a significant association with DFs (p=0.015 and p=0.038 respectively). Median, mean and SD of MTV and TLG for patients with DFs were: 8.90, 13.73, 15.10 and 33.78, and 90.54 and 144.64, respectively. Median, mean and SD of MTV and TLG for patients with non-DFs were: 16.72, 29.70 and 31.09 and 90.89, 210.98 and 382.80, respectively. No significant relationships were observed with SUV variables and DFs. Volume-based variables were significantly associated with OS and DFS, although in multivariate analysis only MTV was related to OS. No SUV variables showed an association with the prognosis. CONCLUSION Volume-based metabolic variables obtained with 18F-FDG PET/CT, unlike SUV based variables, were good predictors of both neoadjuvant chemotherapy response and prognosis.

PET/TC con 18F-FDG como predictor de la biología tumoral y del pronóstico en el cáncer epitelial ovárico

OBJECTIVE To investigate the relationship between maximum standardised uptake value (SUVmax) of ovarian lesions and histopathology subtypes, and their involvement in the response and prognosis of patients with epithelial ovarian carcinoma (EOC). MATERIAL AND METHODS A retrospective analysis of 31 patients with EOC and 18F-FDG-PET/CT before treatment, including an assessment of the SUVmax of ovarian lesion. Histopathological diagnosis and follow-up was performed. A study was made on the relationship between the SUVmax and histological type (type I and II) and tumour stage, as well as the role of various parameters (SUVmax, histology, stage) on the patient outcomes (complete response [CR], overall survival [OS], disease-free survival [DFS], and disease-free [DF] status, at 12 and 24 months). RESULTS The medium SUVmax in type I lesions was lower than in type II (6.3 and 9.3, respectively; P=.03). A 7.1 cut-off was set for SUVmax in order to identify type II EOC (sensitivity: 77.8%, specificity: 69.2%; AUC=0.748; P=.02). No significant relationship was found between tumour stage and SUVmax. CR was more common in early stages; relative risk (RR) of 1.64; P=.003, as well as in type I tumours and a lower SUVmax. Tumour stage was decisive in DFS (P=.04), LE24m (0.07) and OS (P=.08). Longer DFS and a higher percentage of DF 24m were observed in type I tumours (RR: 1.32; P=.26). CONCLUSIONS SUVmax was related to EOC histology, so could predict the response and prognosis of these patients. No association was found between glycolytic activity of the primary tumor with the response and prognosis.

PET/TC con 18F-FDG en la valoración de pacientes con sospecha de síndrome paraneoplásico neurológico

OBJECTIVE This study aimed to determine the diagnostic impact of (18)F-FDG PET/CT based on the clinical features of paraneoplastic neurological syndrome (PNS). MATERIAL AND METHODS Multicenter retrospective and longitudinal study of patients with suspicion of PNS. The clinical picture was classified into classic (CS) and non-classic syndrome (NCS). After the follow-up, the definitive or possible diagnosis of PNS was established. The pictures that did not match any of the previous criteria were categorized as non-classifiable. The state of the onco-neural antibodies was studied. The PET/CT was classified as positive or negative for the detection of malignancy. The relationship between PET/CT findings and the final diagnosis was determined. The differences between variables (Pearson test X(2)) and the relationship between the results of the PET/CT and the final diagnosis were analyzed. RESULTS A total of 64 patients were analyzed, classifying 30% as CS and 42% as NCS. After the follow-up, 20% and 16% of subjects were diagnosed as possible and definitive PNS, respectively. Positive onco-neural antibodies were found in 13% of the patients. A definitive diagnosis of PNS was associated with a positive PET/CT (P=.08). A significant relation between antibodies expression and final diagnosis of neoplasia (P=.04) was demonstrated. The PET/CT correctly localized malignancy in 5/7 cases of invasive cancer. CONCLUSIONS The PET/CT showed a higher percentage of positive results in patients with definitive diagnosis of PNS. Despite the low prevalence of malignancy in our series, the PET/CT detected malignancy in a significant proportion of patients with invasive cancer.