PERCIST and Hopkins criteria and PET/CT metabolic parameters as prognostic factors in squamous head and neck cancer.

AIM: To assess the clinical utility of PERCIST and Hopkins criteria and changes in [18F]FDG PET/CT quantitative parameters as prognostic factors for progression-free survival (PFS) and cancer-specific survival (CSS) in patients with head and neck squamous cell carcinoma treated by chemoradiotherapy. MATERIAL AND METHODS: Forty patients (34 men) diagnosed with head and neck squamous cell carcinoma were retrospectively assessed over an interval of 8 years. PERCIST and Hopkins criteria were used to assess response to treatment. Variations in the metabolic parameters maximum SUV (ΔSUVmax), metabolic tumor volume (ΔMTV) and total lesion glycolysis (ΔTLG) between pre- and post-treatment PET/CT studies were also determined. The Cox regression model, ROC curves and the Kaplan-Meier method were used for the analysis of prognostic factors and survival curves. RESULTS: The mean follow-up was 39.4 months, with 24 progressions and 22 deaths. Both PERCIST and Hopkins criteria and the three metabolic parameters were predictive factors in the univariate analysis and only ΔSUVmax was in the multivariate analysis. Survival analysis showed statistically significant differences in PFS and CSS curves for the five parameters considered. CONCLUSION: Application of PERCIST and Hopkins criteria as well as ΔSUVmax, ΔMTV and ΔTLG from PET/CT studies proved to be prognostic factors for survival in patients in our setting for treating head and neck cancer. The results may help to personalize treatment.

Completion of the informed consent in radioguided surgery by the General Surgery and Nuclear Medicine services of a radioguided surgery unit.

OBJECTIVE: To identify the frequency of errors in informed consent documents in radioguided surgery in a third level hospital and to detect possible causes or factors associated with a greater risk of error. MATERIAL AND METHODS: Informed consent forms of a total of 369 radioguided surgery interventions, completed by the Nuclear Medicine and General Surgery services, were analyzed, and the degree of completion of the forms and its correlation with the physicians responsible, type of pathology, intervention, and waiting time were compared with the completion of consent by another specialty. RESULTS: Errors were identified in 22 consent forms from Nuclear Medicine and 71 from General Surgery. The most common error was the absence of identification of the physician responsible (17 in Nuclear Medicine, 51 in General Surgery), and the second most common was the absence of a document (2 in Nuclear Medicine, 20 in General Surgery). There were significant differences in the errors made depending on the doctor in charge, with no significant correlation with the other variables. CONCLUSIONS: The physicians responsible were the main factor associated with a greater risk of error in the completion of informed consent forms. Further studies are needed to analyze the causal factors and possible interventions to minimize errors.

[Radioguided surgery of intestinal carcinoid tumor relapse. Role of SPECT-CT]. / Cirugía radiodirigida de metástasis de tumor carcinoide intestinal. Importancia de la realización de SPECT-TAC.

We present a patient with clinical suspicion of intestinal carcinoid relapse confirmed by a somatostatin receptor scintigraphy. A very intense somatostatin avid abdominal lesion was located and radioguided surgery was proposed. Prior to the procedure, we performed a SPECT-CT that made it possible to detect and localize the lesion anatomically, thus facilitating the performance of the radioguided procedure. Furthermore, it modified the planning of the intervention with the adequate physical and human resources to prevent the possible surgical complications.

[Optimization of sentinel lymph node biopsy in breast cancer by intraoperative axillary palpation]. / Optimización de la biopsia selectiva de ganglio centinela en el cáncer de mama mediante palpación axilar intraoperatoria.

INTRODUCTION: Sentinel node biopsy (SNB) by radioisotopes is a widely accepted and reliable surgical method for staging breast cancer in patients with unknown positive axillary lymph nodes involvement. The main limitation of this method is due to the appearance of false negatives that may be caused by tumor lymph node blockage of the sentinel lymph node and uptake in the neighboring lymph nodes. Infiltered sentinel nodes are generally increased in size and firm. Thus, they can be detected by intraoperative palpation, even when there is no uptake by the radiotracer. AIM: To reduce the false negative rates by applying intraoperative axillary palpation after SNB. METHOD: Over a two-year period, we complemented the SNB in 168 patients with careful intraoperative axillary palpation, detecting and removing all the palpable suspicious lymph nodes (SLN) that were analyzed as sentinel nodes RESULTS: In 32 out of 168 patients, 50 palpable SLN were found. In 3 out of 32 patients, 4 infiltrated SLNs were demonstrated with negative SNB and positive axillary lymphadenectomy. Thus, intraoperative palpation avoided false negative results. In one patient, one palpable SLN with tumor involvement was observed and SNB was also positive. In the remaining 28 patients, the histological analysis of 45 SLN was negative for tumor but SNB was positive in 3 patients. CONCLUSION: Intraoperative axillary palpation, once the SNB was done, reduced the false negative rate. Thus, we consider that it should be included as one more part of this procedure.

[Negative predictive value of (123)I Ioflupane SPECT in movement disorders]. / Valor predictivo negativo del SPECT con Ioflupano (123)I en los trastornos del movimiento.

OBJECTIVE: A non-degenerative etiology is supported by a normal SPI [normal SPECT with 123I-Ioflupane (SPI)] in a patient with movement disorders (MD). METHOD: A total of 196 SPIs were conducted during the period of 2004/05. Of these, 44 were selected in order to rule out degenerative MD (DMD), the results being normal in these patients. The clinical background of these patients were reviewed in a minimum period of 24 months (range 24-40), collecting the diagnoses reached by the neurology specialists. The SPI were evaluated using a consensus, according to subjective criteria and quantification. RESULTS: Thirty-six of the 44 patients (81%) were identified at 2 years of having nondegenerative movement disorders: 18 as essential tremor, 5 as drug-induced disorder, 4 as vascular disease, 3 as peripheral polyneuropathy, 2 postural tremors, 1 writer's cramp, 1 psychogenic tremor, 1 intercranial hypertension and 1 fibromyalgia. The remaining 8 patients were diagnosed with Parkinson's disease in 5 cases, 1 corticobasal degeneration, 1 multisystemic atrophy and another degenerative Parkinsonism with unclear etiology. CONCLUSION: The SPI in our hospital has a lower negative predictive value than the data reported in the literature. The false negatives could be explained because most of our patients come from neurologist physicians who are not movement disorder experts. In addition, a small proportion of degenerative Parkinsonism could evolve with normal SPI.

67-Gallium SPECT/CT in febrile syndromes of unknown origin. / SPECT/TC con galio-67 en los síndromes febriles sin foco conocido.

INTRODUCTION AND OBJECTIVE: Febrile syndromes of unknown origin (FSUO) are complex processes in hospital practice. Their management includes an exhaustive medical history and examination, as well as an extensive number of biochemical tests. If these are inconclusive, diagnostic imaging techniques such as SPECT/CT with 67-Gallium Citrate (67Ga-SPECT/CT) could play an important role. We evaluated its role in the management of FSUO in our healthcare area. MATERIAL AND METHODS: We reviewed 57 patients who underwent a 67Ga-SPECT/CT due to a FSUO (32 women and 25 men, age range: 32-83 years old) obtaining scintigraphic findings, previous treatments and final diagnosis. Values of sensitivity, specificity, positive predictive values (VPP) and negative values (NPV) were obtained and compared with the results for PET/CT with 18Fluor-deoxy-glucose (18F-FDG PET/CT) found in the literature. RESULTS: The diagnoses found were: infection in 27/57 (47%), inflammatory disease in 15/57 (26%), neoplasm in 1/57 (1.75%) and patients without final diagnosis in 14/57 (24%). The statistical values of 67Ga-SPECT/CT were: sensitivity, specificity, PPV and NPV of 67%, 93%, 97% y 48%, respectively which were slightly lower than those found for the 18F-FDG PET/CT (86%, 52%, 70% and 92%, respectively). The diagnostic yield was 73% which increased to 80% in the patients who lacked empirical treatment. CONCLUSION: Despite the better results of 18F-FDG PET/CT, 67Ga-SPECT/CT behaved as a useful technique in the management of FSUO. It is advisable to use it if 18F-FDG PET/CT is not available.

Pancreatic accessory spleen. False positive with 99mTc-Octreotide.

The case is presented on a patient with abdominal pain and suspicion of neuroendocrine tumor in the tail of the pancreas shown in the abdominal CT and MRI. Whole-body scintigraphy and abdominal SPECT/CT with 99mTc-octreotide were performed that showed a nodular lesion partially on the posterior side of the pancreas tail. This nodule showed faint tracer uptake, and was reported as probable neuroendocrine tumor. Partial pancreatectomy and splenectomy were performed, and the histological study identified the lesion as an ectopic spleen. There are similar cases in the literature that match these findings, but this lesion is still frequently diagnosed after performing unnecessary surgery. When an asymptomatic intrapancreatic mass is detected, an accessory spleen should be considered and specific diagnostic techniques should be performed, such as labeled and denatured red blood cell SPECT/CT.

Contribution of brain perfusion SPECT in the diagnosis of a case of cerebral malaria. / Aportación diagnóstica de la SPECT de perfusión cerebral en un caso de malaria cerebral.

Cerebral malaria is a serious complication of infection with Plasmodium falciparum. Its pathophysiological mechanisms and clinical manifestations are still currently being studied. Structural imaging techniques such as CT and MRI provide non-specific information during the diagnostic process. However, there are hardly any references on the use and potential benefits of radioisotope procedures for this pathology. In this article we present the case of a patient diagnosed with cerebral malaria treated in our centre, subjected to progressive monitoring using SPECT perfusion.

Role of SPECT-CT in breast cancer sentinel node biopsy when internal mammary chain drainage is observed.

INTRODUCTION: SPECT-CT in the detection of the sentinel lymph node (SLN) of breast cancer offers known advantages over conventional planar lymphoscintigraphy. Sometimes, it shows atypical findings like mediastinal lymphatic drainage. We have evaluated these atypical findings showed by SPECT-CT performed in patients with migration to the internal mammary chain (IMC) and their roles in the management of the patients. MATERIALS AND METHODS: We reviewed the 56 lymphoscintigraphies (planar and SPECT-CT) of 56 women (average age: 55 years) diagnosed with breast cancer with IMC migration observed in the planar images. We compared the two techniques, obtaining the number of depicted nodes, atypical locations, their exact anatomical location and their role in the management of the patient. RESULTS: Planar images showed a total number of 81 IMC nodes. SPECT-CT showed 74 nodes in the IMC territory and 14 mediastinal lymphatic nodes in 6 patients. Out of the 81 IMC nodes reported by planar images, seven corresponded to mediastinal nodes. Planar and hybrid images showed 110 and 130 axillary nodes, respectively. SPECT-CT showed additional findings in five patients: three infraclavicular and two supraclavicular nodes that were exactly located. One intramammary node was discarded by the SPECT-CT as a focal skin contamination. CONCLUSION: Mediastinal nodes are unexpected, but not uncommon findings that are important in the planning of SLN biopsy. SPECT-CT found more nodes than planar images, being able to separate mediastinal and IMC nodes, helping to exactly depict the SLN and its relations with anatomical structures.

[99m-Tc sestamibi scintigraphy in primary hyperparathyroidism. Importance of lateral projections using a pin-hole collimator]. / Gammagrafía con sestamibi-Tc99m en el hiperparatiroidismo primario. Importancia de las proyecciones laterales con colimador pin-hole.

UNLABELLED: 99mTc-Sestamibi double-phase scintigraphy has been improved with digital and tomographic procedures as well as additional projections. Since two years ago, we have introduced additional early lateral views of neck to the conventional double-phase scintigraphy. We have tried to give anatomic data about the depth of the adenomas and to evaluate the possibility of obviating the late images of the double-phase study. METHOD: Two observers reviewed 50 studies performed for primary hyperparathyroidism in two different ways. The first one reviewed only conventional double-phase studies and the second one, with the additional report of the lateral views. RESULTS: in 32/50 patients (64 %) the report of the additional lateral views and the conventional early views was enough to diagnose parathyroid adenomas. No additional lesions were observed in the late views. These views did not provide any additional useful data and could have been obviated. Four ectopic adenomas were found, 1 mediastinal and 3 in paraesophagic area; three intrathyroidal focus; all of these atypical lesions were identified by lateral pinhole views. CONCLUSION: The performance of additional lateral projections of the parathyroids supplies additional information to the surgeon on the depth of the lesion in atypical sites and would have made it possible to obviate the late phase in more than half of the patients since this did not supply additional information to that of the early images that had reached a diagnosis.

[False positive with Tl-201 in the study of Ewing's sarcoma of the astragalus caused by reflex sympathetic dystrophy]. / Falso positivo con T1201 en el estudio de un sarcoma de Ewing de astrágalo causado por una distrofia simpático-refleja.

We describe a 14 year old male, diagnosed of Ewing sarcoma in left astragalus. We performed two 201-Thallium scan for evaluating the response to chemotherapy (before and after the treatment). The scan performed after chemotherapy showed patchy uptake in astragalus, calcaneus and some joints of the foot. The following radiology and scintigraphy diagnosed a reflex sympathetic dystrophy in the left foot due to disuse of the limb. The 201-Thallium overestimated viability of the tumour for this reason. We must discard the presence of this kind of associated pathology in order that they could be cause of false positives.

[Bone metastasis versus insufficiency fractures due to pelvic radiotherapy for gynecologic neoplasm]. / Metástasis óseas versus fracturas por insuficiencia en pelvis irradiadas por neoplasia ginecológica.

Five cases of patients with gynecological neoplasm (four cervix carcinoma and one endometrial sarcoma) who underwent pelvic external radiotherapy and intracavitary brachytherapy in whom pathologic pelvic uptake was found in the bone scan are presented. The diagnosis was pelvic insufficiency fractures due to radiotherapy adverse effects on the skeletal system confirmed by CT and by the favorable scintigraphy and clinical outcome. Both bone metastases and insufficiency fractures must be considered in the differential diagnosis of bone pain in irradiated pelvises. The bone scintigraphy detects these insufficiency fractures early and can show a typical symmetric uptake pattern. In asymmetric lesions, the CT and clinical follow-up as well as the scintigraphic evolution of the lesions should confirm the findings of the bone scintigraphies.

Coexistence of two different types of lymphoma in a patient with Sjögren's syndrome. The usefulness of the PET-CT.

Sjögren syndrome is a chronic systemic autoimmune disease in which there is an increased risk of developing non-Hodgkin's lymphoma. Neoplastic lung involvement and the coexistence of different histological types of lymphoma are uncommon in these patients. These patients frequently have associated infectious processes, most of them due to oral candidiasis. When there is immunodeficiency, the hematogenous spread of the fungus may affect the lungs. We present the case of a female patient diagnosed with follicular non- Hodgkin lymphoma within the context of long-term Sjögren syndrome. In addition to the neoplastic nodal and splenic disease, the PET-CT study showed extensive lung involvement. Due to suspicion of a false positive result for pulmonary Candida infection, antifungal treatment was initiated, with no response. A further histological study showed the presence of a second and different type of lymphoma.