Predicting locally advanced rectal cancer response to neoadjuvant therapy with 18F-FDG PET and MRI radiomics features.

PURPOSE: Pathological complete response (pCR) following neoadjuvant chemoradiotherapy or radiotherapy in locally advanced rectal cancer (LARC) is reached in approximately 15-30% of cases, therefore it would be useful to assess if pretreatment of 18F-FDG PET/CT and/or MRI texture features can reliably predict response to neoadjuvant therapy in LARC. METHODS: Fifty-two patients were dichotomized as responder (pR+) or non-responder (pR-) according to their pathological tumor regression grade (TRG) as follows: 22 as pR+ (nine with TRG = 1, 13 with TRG = 2) and 30 as pR- (16 with TRG = 3, 13 with TRG = 4 and 1 with TRG = 5). First-order parameters and 21 second-order texture parameters derived from the Gray-Level Co-Occurrence matrix were extracted from semi-automatically segmented tumors on T2w MRI, ADC maps, and PET/CT acquisitions. The role of each texture feature in predicting pR+ was assessed with monoparametric and multiparametric models. RESULTS: In the mono-parametric approach, PET homogeneity reached the maximum AUC (0.77; sensitivity = 72.7% and specificity = 76.7%), while PET glycolytic volume and ADC dissimilarity reached the highest sensitivity (both 90.9%). In the multiparametric analysis, a logistic regression model containing six second-order texture features (five from PET and one from T2w MRI) yields the highest predictivity in distinguish between pR+ and pR- patients (AUC = 0.86; sensitivity = 86%, and specificity = 83% at the Youden index). CONCLUSIONS: If preliminary results of this study are confirmed, pretreatment PET and MRI could be useful to personalize patient treatment, e.g., avoiding toxicity of neoadjuvant therapy in patients predicted pR-.

Platelet-derived growth factor-BB stimulates hypertrophy of peritubular smooth muscle cells from rat testis in primary cultures.

The tunica propria of seminiferous tubules contains a particular type of smooth muscle cell (myoid cells) arranged in a contractile epithelioid layer that is responsible for sperm and tubular fluid flow. Unlike other types of smooth muscle (SM) cells, highly purified populations of peritubular smooth muscle cells (PSMC) survive and maintain their contractile phenotype in primary cultures in controlled conditions. We used this culture model to investigate the response of the SM contractile phenotype to prolonged exposure to platelet-derived growth factor (PDGF), one of the main factors involved in vascular SM pathologies. We observed that 4-day continuous exposure of PSMC to PDGF-BB at nanomolar concentrations in plain medium enhances contractile phenotype traits and induces cell hypertrophy without inducing proliferation. In Northern and Western blotting experiments, SM-alpha-actin transcript and protein were found to be markedly increased in the PDGF-BB-treated samples, which is in line with the formation of conspicuous SM-alpha-actin-containing stress fibers. Moreover, binding sites for endothelin-1 were increased, and the calcium response to the contractile agonist, determined in single fura-2-loaded cells, was enhanced. In response to PDGF-BB, the cells underwent immediate, transient contraction, as seen in a scanning electron microscope, followed by a gradual increase in size, as evaluated by cytofluorometry, and enhancement of protein synthesis. The observed pattern of response to PDGF-BB was not accompanied by cell proliferation, as assessed by [3H]thymidine incorporation and direct cell counts. Unlike other SM cell types, in which proliferation and loss of contractile traits are induced by PDGF, chronic treatment of PSMC with this growth factor results in hypertrophy rather than hyperplasia.

[Early flat colorectal cancer]. / Cáncer recto colónico temprano plano.

We report three cases of flat early colorectal carcinoma which were detected during the examination of 51 surgical specimens of colorectal resection. Two of them were endoscopically diagnosed, but the smallest one was not seen in the luminal instrumental examination. From the bibliographic analysis and our own experience we deduce the importance of flat lesions in the development of early colorectal carcinoma, either originated from pre-existent adenoma or de novo. Flat variants of adenoma, and presumably flush or depressed ones, must be considered as important factors in the early sequence adenoma-cancer. An appropriate endoscopic equipment with employment of additional staining techniques (such as carmine indigo and methylene blue) and the correct investigation during inflation-deflation procedures facilitates the identification of small lesions, their eradication and prevention from advanced forms of colorectal carcinoma.

Is hyperdiploidy of immature ejaculated germ cells predictive of testis malignancy? A comparative study in healthy normozoospermic, infertile, and testis tumor suffering subjects.

The possibility of diagnosing neoplastic testis pathologies by studying immature germ cells released from the seminiferous epithelium and present in the semen has been reported. It has been suggested that carcinoma in situ (CIS) of the testis and testis tumor may be identified by studying specific surface antigenic determinants or ploidy of chromosome 1 of malignant germ cells recovered from the semen. A noninvasive diagnostic approach of this type would be of great interest if we consider that CIS is supposed to precede the development of testicular germ cell tumors and that the frequency of that preneoplastic condition is increased in specific andrologic pathologies. To evaluate the reliability of this diagnostic approach, we have quantified the presence of immature hyperdiploid germ cells in the seminal fluid of normal healthy subjects, of infertile oligozoospermic patients affected by maldescended testis or left vancocele, and of patients suffering from CIS or testis tumor. Cell ploidy was evaluated on seminal cell fractions highly enriched in immature germ cells, by means of in situ hybridization with a DNA-probe specific for chromosome 1. Our observations indicate that chromosome 1 hyperdiploidy is not necessarily a predictive parameter of testis tumoral pathologies. The percentage of hyperdiploid immature seminal germ cells is in fact increased in nontumoral pathologies associated with infertility, such as cryptorchidism and left varicocele.

Resección endoscópica de un leiomioma de esófago mediante la ligadura con banda elástica / Endoscopic resection of esophageal leiomyoma with elastic band ligation

Leiomyoma is the most frequent esophageal benign tumor. It represents 70% of these tumors and 1 to 8% of all esophageal tumors. The majority of cases are asymptomatic and are discovered by chance in endoscopic examinations, and a conservative management is adopted. An endoscopic or surgical treatment can be applied in symptomatic cases, basically depending on the size and the underlying layer. OBJECTIVE: To report the endoscopic resection of an esophageal leiomyoma by using an elastic band ligation. Case report: A 55 year-old man complained of prolonged upper dysphagia with solids during three months. An upper gastrointestinal endoscopy was performed and an elevated lesion of 1 cm in diameter was found in the esophagus, at 25 cm from the upper dental arcade, with smooth surface and adjacent areas of normal mucosa. It was interpreted as a submucosal lesion. A hypoechoic mucosal and submucosal formation with well delimited borders was observed in an endoscopic ultrasonography. The lesion was resected by using an endoscopic band ligation and a subsequent section with a polypectomy snare. The patient evolved uneventfully and was discharged in 24 hours. The endoscopic examinations during the follow-up showed the healing of the resulting scar. Pathologists diagnosis was esophageal leiomyoma. CONCLUSION: The elastic band ligation is a simple, safe, effective and cheap method to be taken into account for the treatment of mucosal and submucosal esophageal lesions.

El leiomioma es el tumor esofágico benigno más frecuente;representa el 70 % de los mismos y el 1 a 8% de todos los tumores del esófago. La mayoría de los casos son asintomáticos y su hallazgo es accidental en estudios endoscópicos, tomándose una conducta conservadora.En los casos sintomáticos se puede decidir un tratamiento quirúrgico o endoscópico, dependiendo fundamentalmente del tamaño y la capa de la pared en la que asienta. Objetivo: Comunicar una resección endoscópicade un leiomioma esofágico mediante el uso de la ligadura con banda elástica. Caso clínico: Se presenta un paciente de 55 años de edad que consultó pordisfagia alta para sólidos, continua y de tres meses de evolución. Se realizó una endoscopía en la que se observóuna lesión elevada de 1 cm de diámetro en esófago, a 25 cm de la arcada dentaria superior, con superficielisa y áreas adyacentes de mucosa sana. Se interpretó la lesión como submucosa. En la ecoendoscopia se apreció una formación hipoecoica de bordes bien delimitados, ubicada en mucosa y submucosa. Se decidió realizar una resección de la lesión utilizando la ligadura endoscópica con banda elástica y posterior sección con asa de polipectomía. El paciente evolucionó favorablemente y fue dado de alta a las 24 horas. Los controles endoscópicos posteriores mostraron una buena cicatrización de la escara resultante. El informe anatomopatológico fue leiomioma esofágico. Conclusión: Laaplicación de la banda elástica es un método simple, seguro, eficaz y de bajo costo para considerar en el manejode las lesiones mucosas y submucosas esofágicas.