68Ga-PSMA-11 PET/CT in patients with occult biochemical recurrence of prostate carcinoma and negative 18F-Choline PET/CT. Preliminary assessment of its clinical use.

OBJECTIVE: To assess the clinical usefulness of 68Ga-PSMA PET/CT studies in patients with occult biochemical recurrence of prostate carcinoma, with negative or inconclusive radiologic and 18 F-Choline PET/CT imaging studies. MATERIAL AND METHODS: Retrospective descriptive study. The first 14 patients with a history of prostate carcinoma, treated with curative intent and presenting suspicion of biochemical recurrence with low PSA values (<3 ng/mL) were selected. Imaging studies, prostate ultrasound, pelvic CT and/or MRI were negative, and all of them had a negative or inconclusive 18F-Choline PET/CT. All patients were referred to 68 Ga-PSMA-11 PET/CT. PROTOCOL: Dose 2.2 M Bq/kg. 20 mg furosemide at start. PET/CT images from skull base to proximal third of thighs at 60 min, and late images at 3 h if needed. RESULTS: The 68 Ga-PSMA-11 PET/CT was able to localize the occult biochemical recurrence in 9 of the 14 patients (64.2%), and it affected the therapeutic attitude in all of them. Four patients (28.5%) obtained a negative or inconclusive 68 Ga-PSMA-11 PET/CT and continued under vigilant approach with PSA controls and imaging studies according to the clinical guidelines. These patients had the lowest PSA values (less than 1 ng/mL). One of the 68 Ga-PSMA-11 PET/CT studies was inconclusive, reporting the presence of a doubtful right iliac adenopathy. CONCLUSION: 68 Ga-PSMA-11 PET/CT allows an early diagnosis, with low PSA values, of occult biochemical recurrence of prostate carcinoma, even in patients with negative 18 F-Choline PET/CT.

Defects and plasticity in ultrastrong supercrystalline nanocomposites.

Supercrystalline nanocomposites are nanoarchitected materials with a growing range of applications but unexplored in their structural behavior. They typically consist of organically functionalized inorganic nanoparticles arranged into periodic structures analogous to crystalline lattices, including superlattice imperfections induced by processing or mechanical loading. Although featuring a variety of promising functional properties, their lack of mechanical robustness and unknown deformation mechanisms hamper their implementation into devices. We show that supercrystalline materials react to indentation with the same deformation patterns encountered in single crystals. Supercrystals accommodate plastic deformation in the form of pile-ups, dislocations, and slip bands. These phenomena occur, at least partially, also after cross-linking of the organic ligands, which leads to a multifold strengthening of the nanocomposites. The classic shear theories of crystalline materials are found to describe well the behavior of supercrystalline nanocomposites, which result to feature an elastoplastic behavior, accompanied by compaction.

18F-FDG PET/CT and sentinel lymph node biopsy in the staging of patients with cervical and endometrial cancer. Role of dual-time-point imaging.

OBJECTIVE: Definitive staging for cervical (CC) and endometrial cancer (EC) takes place once surgery is performed. The aim of this study was to evaluate the role of PET/CT in detecting lymphatic metastasis in patients with CC and EC using dual-time-point imaging (DPI), taking the histopathological results of sentinel lymph node (SLN) and lymphadenectomy as the reference. MATERIAL AND METHODS: A prospective study was conducted on 17 patients with early CC, and 13 patients with high-risk EC. The patients had a pre-operative PET/CT, MRI, SLN detection, and lymphadenectomy, when indicated. PET/CT findings were compared with histopathological results. RESULTS: In the pathology study, 4 patients with CC and 4 patients with EC had lymphatic metastasis. PET/CT showed hypermetabolic nodes in 1 patient with CC, and 5 with EC. Four of these had metastasis, one detected in the SLN biopsy. Four patients who had negative PET/CT had micrometastasis in the SLN biopsy, 1 patient with additional lymph nodes involvement. The overall patient-based sensitivity, specificity, positive and negative predictive values, and accuracy of PET/CT to detect lymphatic metastasis was 20.0%, 100.0%, 100.0%, 87.9%, and 88.2%, respectively, in CC, and 57.1%, 88.9%, 66.7%, 84.2% and 80.0%, respectively, in EC. DPI showed higher retention index in malignant than in inflammatory nodes, although no statistically significant differences were found. CONCLUSIONS: PET/CT has low sensitivity in lymph node staging of CC and EC, owing to the lack of detection of micrometastasis. Thus, PET/CT cannot replace SLN biopsy. Although no statistically significant differences were found, DPI may help to differentiate between inflammatory and malignant nodes.

PET/CT with [18F] fluorodeoxyglucose in the assessment of metabolic response to neoadjuvant chemotherapy in locally advanced breast cancer.

AIM: The aim of this paper was to prospectively evaluate FDG PET/CT in the assessment of metabolic response to neoadjuvant chemotherapy and correlation with tumor cellularity in locally advanced breast cancer. METHODS: Images were acquired with a PET/CT scanner in 50 patients at baseline and after completion of treatment, just before surgery. All findings were confirmed by histopathological analysis. PET/CT quantification (SUVmax) at baseline and after finishing neoadjuvant chemotherapy (4 cycles of epirubicin + cyclophosphamide +/- taxanes) were compared using RECIST criteria and Miller & Payne (M&P) scale. RESULTS: Baseline mean tumor size was 4.4±1.6 cm. Thirty eight patients were considered responders and 12 nonresponders. According to M&P scale, 10 patients had good prognosis (grades 4-5) and 40 patients had bad prognosis (grades 1-3). All patients with grade 5 M&P had no significant postchemotherapy FDG uptake. Patients with bad prognosis had lower SUVmax variation (∆SUVmax) than patients with good prognosis (60.7% vs. 80.5%, P=0.0016). ∆SUVmax was lower in nonresponders than in partial responders according to RECIST criteria (38.9% vs. 67.6%, p<0.001), and was also lower in partial responders than complete responders (67.6% vs. 85.4%, P=0.005). A cut-off ∆SUVmax value of 52% differentiates responders from nonresponders with a sensitivity of 86% and a specificity of 90%. Probability densities of the ∆SUVmax (%) for stable disease (<45), partial (>45 to <82) and complete response (>82) showed an overall accuracy of 78% (Weighted Kappa=0.74). CONCLUSION: PET/CT is useful to monitor response to neoadjuvant chemotherapy in locally advanced breast cancer. ∆SUVmax on PET/CT correlates with tumor cellularity after completion of neoadjuvant chemotherapy.

[Sentinel node in gynaecological cancers. Our experience]. / Ganglio centinela en cánceres ginecológicos. Nuestra experiencia.

UNLABELLED: Although sentinel lymph node (SLN) identification is widespread used in melanoma and breast cancer some concerns exist in other malignancies, such gynaecologic cancers, and this staging method has not been adopted in many centers due to lack or large validation studies. AIM: To evaluate the applicability and results of SLN technique in gynaecological malignancies referred to our institution. METHOD: We studied 155 patients with different malignancies (70 vulvar, 50 cervical and 35 endometrial cancers). The day before surgery a lymphoscintigraphy was performed by injecting 111 MBq of (99m)Tc-nanocolloid in several ways depending on the type of cancer studied. Intraoperative detection of the SLN was always performed by using a hand-held gammaprobe and, in 100 cases with the aid of blue dye injection (70 vulvar and 30 in cervical cancer) few minutes before surgical intervention. Pathological study of SLN was performed in all cases. Lymphadenectomy was done in all cervix and endometrial cancer patients and in the first 35 vulvar cancer patients. RESULTS: Pre-surgical lymphoscintigraphy demonstrated one, at least, SLN in 97% of vulvar cancer patients, 92% in the cervical malignancy and 64% in the endometrial cancer patients. During surgery, SLN was harvested in 97%, 90% and 62% of patients, respectively. The pathological study showed metastases in 24.2%, 8.8 and 4.5% of patients with vulvar, cervical and endometrial cancer, respectively. The false negative percentage was 5.5% in vulvar cancer patients, with 2 cases in the endometrial cancer and without any case in the cervical cancer patients. CONCLUSION: Lymphoscintigraphy is a relatively simple and useful technique to identify the SLN in this kind of tumours. However, in endometrial cancer more effort has to be made to reach a suitable result. Sentinel lymph node biopsy seems to be a reliable technique in vulvar and cervical malignancies.

[In-transit sentinel lymph nodes in malignant melanoma. What is their importance?]. / Ganglios centinela ''en tránsito'' en el melanoma maligno. Cuál es su importancia?

UNLABELLED: The sentinel lymph node (SLN) is the first node in a lymph node basin to receive direct drainage from the primary tumour. However, in some cases, lymphoscintigraphy images demonstrate the presence of lymph nodes located in the area between the primary tumour and the first regional lymph node basin. These nodes are called in-transit nodes and have to be considered SLNs as well. AIM: It was to determine the incidence and location of in-transit SLNs in patients with malignant melanoma and to evaluate whether it is necessary to harvest them. METHOD. Nine hundred patients with malignant melanoma were included. Lymphoscintigraphy was performed on the day before surgery following intradermal injection of 74-111 MBq of 99mTc-Nanocolloid in four doses around the primary lesion or the biopsy scar. RESULTS: The presence of in-transit SLNs was revealed in 80 patients. During surgery, in-transit SLNs were identified and excised in all but 3 patients (96.2 %). Metastatic cell deposits were identified in these in-transit SLNs in 15 patients (19.4 %), with 4 patients with no tumour involvement of the regional lymph node basin. CONCLUSIONS: Lymphoscintigraphy is mandatory in the location of in-transit SLNs. Moreover, although the incidence of these nodes is relatively low in malignant melanoma, the presence of metastatic cells in these in-transit SLNs reaches a significant percentage. Therefore, excision of in-transit SLNs is necessary in all cases.

[Potential use of bone marrow scintigraphy in suspected prosthetic hip infection evaluated with 99mTc-HMPAO-leukocytes]. / Valor de la gammagrafía de médula macrofágica en el diagnóstico de infección de prótesis total de cadera estudiada con leucocitos Tc-HMPAO.

AIM: To evaluate the usefulness of (99m)Tc-Sulphur colloid when combined with leukocyte scintigraphy in suspected prosthetic hip infection, comparing the results with information from (99m)Tc-HMPAO-leukocyte scintigraphy alone. MATERIALS AND METHODS: Seventy patients (42 women, 28 men; mean age 68 +/- 13 years) with painful hip prostheses and suspicion of infection were evaluated prospectively. All patients had bone scintigraphy, (99m)Tc-HMPAO-labelled white blood cell scintigraphy and (99m)Tc-Sulphur colloid bone marrow scintigraphy. ESR and CRP levels were measured in all patients. The final diagnosis was made with microbiological findings or by clinical follow up of at least 12 months. RESULTS: Infections were diagnosed in 12 of the 70 patients (3 coagulase-negative Staphylococcus, 2 Staphylococcus aureus, 2 Staphylococcus epidermidis, 2 enterococcus and 3 polymicrobial agents). ESR and CRP values were higher in patients with infection than in patients without infection (51.8 +/- 29.4 vs. 25.4 +/- 16.4 and 2.8 +/- 2.2 vs. 1.1 +/- 1.3, respectively; p < 0.05). Bone scintigraphy did not show a characteristic pattern to differentiate infection from aseptic loosening. The pool phase of the bone scintigraphy was positive in only 3/12 patients with infection (25 %). Sensitivity and specificity of the leukocyte scintigraphy was 83 % and 57 %, respectively. When the results of the bone marrow scintigraphy were added, these values increased to 92 % and 98 %, respectively. CONCLUSION: Performing bone marrow scintigraphy significantly improves results when compared with leukocyte scintigraphy alone in the diagnosis of infected hip prostheses. Bone scintigraphy did not help to differentiate aseptic loosening from infection in this series.

Localising imaging in secondary hyperparathyroidism.

Preoperative imaging has proved its use successful in the localization of solitary parathyroid adenomas in patients with suspected primary hyperparathyroidism. However, due to multiglandular disease at presentation patients with renal hyperparathyroidism need to be analyzed separately, making the usefulness of imaging techniques controversial. Recently, improved methods of functional imaging like parathyroid scan with 99mTc-sestamibi or positron emission tomography, especially when combined with computed tomography, can provide additional quantitative and qualitative information that has yet to be assessed. Nuclear medicine procedures could prove useful not only in preoperative diagnosis, but also in the selection of medical or surgical therapeutic alternatives in secondary hyperparathyroidism patients. There is evidence that 99mTc-sestamibi uptake in parathyroid hyperplasia or adenoma is related to biochemical markers of parathyroid function. We are only beginning to identify the factors involved in radiotracer uptake by parathyroid cells and how it can be modulated to obtain more accurate results. This review analyzes the current use of non-invasive imaging modalities in patients with secondary hyperparathyroidism, taking into account the latest trends in the field combining anatomic and functional modalities and the relevant factors linked to radiotracer uptake in abnormal hyperfunctioning parathyroid glands.

[Localization of sentinel node in squamous cell carcinoma of the penis. Initial experience]. / Localización del ganglio centinela en el carcinoma escamoso de pene. Experiencia inicial.

OBJECTIVE: To assess the validity of radioguided sentinel node biopsy in squamous cell penile carcinoma. MATERIAL AND METHODS: Fifteen patients were studied. The first 5 patients were included in a group for validation of the technique, in which a standard inguinal lymphadenectomy was performed after the procedures described below. The remaining 10 patients were included in the technique application group. The day before surgery, lymphoscintigraphy was performed on all patients. During the operation, radioguided biopsy to locate the sentinel node was done. Methylene blue dye was injected shortly before surgery in 10 patients. All patients were followed for an average of 32 months. RESULTS: In the validation group, lymphoscintigraphy revealed inguinal drainage in 5/5 patients. Unilateral metastases were detected in 3/5 patients. No metastatic nodes were detected among the nodes removed during inguinal lymphadenectomy. In the application group, lymphoscintigraphy showed inguinal drainage in 9/10 patients. Nineteen nodes were removed, none of which showed tumour involvement. During the follow-up period, no disease progression or recurrence were observed in either patient group. CONCLUSIONS: Radioguided localization and biopsy of the sentinel nodes can avoid unnecessary lymphadenectomies in patients with squamous cell penile carcinoma and high or intermediate risk of lymph node involvement. This technique shows high reliability and negative predictive value in penile carcinoma.

[Value of MR imaging of the fetal kidney]. / Apport de l'IRM dans l'étude du rein foetal.

Sonography is the imaging modality of choice for initial evaluation of the fetus. However, the role of MR imaging for fetal evaluation is expanding. Based on a review of seven cases, the role of MRI to further characterize renal abnormalities detected at US, especially hyperechoic kidneys, is demonstrated.

[Intermittent ureteropelvic junction obstruction and aberrant vessel to the lower pole of the kidney in children]. / Obstruction intermittente de la jonction pyélo-urétérale et vaisseaux polaires inférieurs chez l'enfant.

Intermittent ureteropelvic junction obstruction in children is a distinct clinical syndrome, it is often associated with an anteriorly crossing aberrant vessel to the lower pole of the kidney. The presence of these vessels increases the risk of complication and requires surgical management. CT scan is already the best exam to find these vessels in adults before treatment. It seems to be also efficient in children. This case report illustrates this indication.

[Testicular feminization, germinal tumor, NK lymphoma: what is the relationship?]. / Testicule féminisant, tumeur germinale, lymphome NK, quel lien?

CASE REPORT: The authors report the case of a ten-year-old girl, who had been treated for a malignant germinal tumour five years before, presenting with a leukaemia-like syndrome associating bone pain, liver and spleen nodules and bone marrow involvement. The cyto-pathological analysis showed undifferentiated cells and CD56 and protein S100 were found as the only positive markers. The child received several subsequent lines of chemotherapy and ultimately died of the disease. COMMENTS: Particular cytogenetic abnormalities were observed (iso1q10, iso6p10) and were in favor of an unusual NK cell lymphoma. CONCLUSION: This analysis revealed a XY genotype (testicular feminization syndrome).

[Imaging of the hip in healthy children in MRI: evaluation of the acetabular coverage]. / Imagerie de la hanche de l'enfant sain en IRM: évaluation de la couverture cotyloïdienne.

PURPOSE: To define with MR imaging a reference value for acetabular coverage on coronal and sagittal images for a population of healthy children. MATERIALS AND METHODS: 36 children (72 hips) where prospectively studied over 1 year. T1-weighted spin-echo images in both coronal and sagittal planes were obtained. Slice thickness was 4 mm. Measurement of acetabular coverage (AHI: Acetabular-Head Index) was made in both planes with two different landmarks: bone and cartilage. Study of the evolution with age was made. RESULTS: The acetabular coverage is symmetrical and decreases with age. Its measurement is reproducible. CONCLUSION: This study shows that measurement of acetabular coverage (AHI) is easily obtained at MR imaging and is reproducible. We suggest 83 (mean 1SD) as the inferior limit for AHI based on cartilage measurements. We introduce sagittal values, never published. We believe that MR, by its ability to demonstrate the cartilaginous surfaces, will play a major role in the true understanding of the anatomical relationship between the femoral head and the acetabulum.

[MRI study of the arterial ligament and the left pulmonary artery in the preoperative staging of left upper lobe bronchial cancers]. / L'étude par IRM du ligament artériel et de l'artère pulmonaire gauche dans le bilan d'extension préopératoire des cancers bronchiques lobaires supérieurs gauches.

PURPOSE: To demonstrate that the ligamentum arteriosum is visible by precisely-oriented MRI. To demonstrate the predictive value of the ligament involvement for left upper lobe cancer surgery. MATERIAL AND METHODS: Fifteen controls, age-matched with bronchial cancer patients, were studied to establish how the ligamentum arteriosum could best be visualized on MRI. Visibility was optimal on RASE T1-weighted sequences on the frontal and sagittal oblique planes (aorto-pulmonary window). Acquisitions were performed with a body coil, 7 mm slices, 480 mm Fov, on a Magnetom Expert, 1T Siemens machine. Forty five patients with left upper lobe cancer underwent MRI investigation after CT had shown mediastinal proximity of the left pulmonary artery and the tumor. They underwent surgery with manual localization of the ligament at the beginning of the procedure. Findings and operative decisions were compared with those of MRI, establishing its predictive value. MRI defined the tumor-ligament and tumor first centimeters of the left pulmonary artery (LPA) relationships. RESULTS: MRI ligamentum visibility was about 87%. Ligament non-involvement on MRI (n = 23) was confirmed at surgery in all cases (100% concordance). Involvement suggested on MRI was confirmed in 18 cases and surgery was impossible or unsatisfactory. There were four false-positives with successful surgery (8% false positives). CONCLUSION: When CT shows left lobe cancers extending in the mediastinum towards the LPA, precisely-oriented MRI assesses surgical difficulty and resectability by demonstration involvement of the ligamentum and the first two centimeters of the LPA.

[Right tracheal bronchus]. / Bronche trachéale droite.

We present 3 cases of tracheal bronchus. The right tracheal bronchus is an uncommon anomaly, more frequent however than on the left side. Two variations are knows, with or without real ectopy. The radiologist can recognize this abnormal bronchus on the CT slices. Most often it is a non-pathogenic finding (unlike the left-sided anomaly). One of the cases, however, had lung cancer in the segment ventilated by the anomalous right bronchus.

The effect of pupil and observation distance on the contrast sensitivity function.

Measuring the contrast sensitivity function (CSF) is becoming more frequent in the analyses that are routinely done in optometric practice. This measurement is generally done in far vision, and the observation distance and its effects are not considered to significantly alter this function. Among these effects we should point out the accommodation of the visual optical system to the stimulus and the errors in accommodation associated with this, changes in pupil diameter and therefore in retinal illumination when the observation distance changes, the different level of aberrations (spherical aberration, astigmatism) for different cases, and so on. All of these factors contribute to the fact that the contrast sensitivity of a visual system varies according to the accommodative stimulus. In this study we attempt to clarify the influence of these different parameters by evaluating the CSF for three observation distances. The study was done in monocular vision, with a natural pupil and with a 3 mm artificial pupil that made it possible to maintain the same level of retinal illumination for all distances.