[A colon adenocarcinoma and a pharyngeal carcinoma incidentally detected by means of (18)F-FDG PET in a patient diagnosed of lung cancer]. / Adenocarcinoma de colon y carcinoma faríngeo detectados incidentalmente mediante (18)F-FDG PET en paciente diagnosticado de cáncer de pulmón.

It is not uncommon to find two or more tumors in the same patient, usually based on similar etiologic factors or the use of radiotherapy and/or chemotherapy. This occurs quite often in the case of lung cancer. In this sense, the positron emission tomography with (18)F-FDG (FDG-PET) is widely used for the diagnosis and treatment of cancer patients. It is also especially useful in patients with solitary pulmonary nodule, bronchogenic carcinoma, head and neck cancer, colon cancer, tumors of unknown origin, lymphomas, etc. Its capacity to detect previously unsuspected second or third primary tumors has also been demonstrated. We report a clinical case showing how two synchronous cancers were incidentally detected in a 73-year old patient diagnosed with lung cancer and referred for (FDG-PET) study.

[18F-FDG PET-CT in a case of solitary plasmacytoma of the soft palate]. / Tomografía por emisión de positrones con ¹8F-fluorodeoxy-glucosa en un caso de plasmocitoma solitario de paladar blando.

Solitary plasmacytoma is an uncommon tumor of plasma cells that can appear in the head and neck. It must be differentiated from multiple myeloma because of its initial presentation. A case of solitary plasmacytoma on the palate is presented. Furthermore, role of ¹8F-fluorodeoxyglucose Positron Emission Tomography (¹8F-FDG-PET) in its initial staging is analyzed.

[Clinical impact of FDG-PET in patients with suspected recurrent ovarian cancer]. / Impacto clínico de la PET-FDG en pacientes con sospecha de recurrencia de cáncer de ovario.

AIM: To evaluate the efficacy and clinical impact of FDG-PET in patients with suspected recurrent ovarian cancer. METHODS: Between October 2001 and October 2006, we retrospectively studied 49 FDG-PET performed in 40 women (age: 52.4 +/- 12.2 years) with ovarian cancer, who had suspicion of recurrent disease by positive morphologic imaging tests (MIT) or increased tumour markers and negative MIT. All patients underwent whole body FDG-PET after the injection of 370-434 MBq of (18)FDG. The results were confirmed by histology in 31 cases, and by clinical-radiological follow-up in 18. RESULTS: Prevalence of disease was 79.6 %. We obtained a global sensitivity and positive predictive value of 87.2 % and 87.2 %, and an accuracy of 79.6 %. Results led to a change in the patient's management in 25 cases (51 %). Subgroup results were: Sensitivity of 81.8 % in patients with increased tumour markers and negative MIT, and 89.3 % in patients with operable malignant lesions. CONCLUSIONS: FDG-PET has high sensitivity and clinical impact in patients with suspicion of recurrent ovarian cancer. Better results were obtained in patients with increased tumour markers and negative MIT.

[Evaluation of efficacy and clinical impact of FDG-PET on patients with potentially resectable non-small cell lung cancer]. / Evaluación de la eficacia y el impacto clínico de la PET-FDG en los pacientes con carcinoma broncopulmonar no microcítico candidatos a cirugía.

AIMS: We have evaluated the efficacy and clinical impact of FDG-PET for staging patients with potentially resectable non-small cell lung cancer (NSCL) in CT. MATERIALS AND METHODS: We have prospectively studied 115 patients (104 M/11 F and mean age: 59 years old) with diagnosis of potentially resectable NSCL, (resectable criteria: Stage

[Bone metastases from unknown primary. FDG-PET detection of two synchronous tumors]. / Metástasis óseas de tumor primario desconocido. Detección mediante PET-FDG de dos tumores sincrónicos.

A 60-year-old woman presented with noncardiac chest pain over months and negative laboratory findings. Conventional imaging methods and bone scintigraphy detected bone lesions suggesting metastatic disease from an unknown primary tumor. An 18FDG-PET scan performed to orient the search for the primary tumor found focal lesions suggesting lymphoma and identified a focal thyroid lesion and a cervical lymph node accessible for biopsy. The biopsy of this lymph node incidentally detected a papillary differentiated thyroid cancer (DTC), since the existence of a non-Hodgkin's lymphoma was confirmed after a new biopsy. After confirming the presence of a lymphoma, 18FDG-PET enabled the initial staging of the tumor, the evaluation of the response to treatment, and follow-up for detection of recurrence. On the other hand, 18FDG-PET incidentally detected a DTC.

[Evaluation of efficacy and clinical impact of positron emission tomography with 18F fluoro-deoxyglucose in patients with suspicion of recurrent head and neck cancer or distant metastases]. / Evaluación de la eficacia y el impacto clínico de la tomografía de emisión de positrones con 18F-FDG en pacientes con sospecha de recurrencias locales y metástasis de carcinomas de cabeza y cuello.

AIMS: To evaluate the efficacy and clinical impact of Positron Emission Tomography with FDG (FDG-PET) in patients with suspected recurrent head and neck cancer or distant metastases. MATERIALS AND METHODS: Sixty patients (12 women and 48 men) with suspicion of recurrent head and neck cancer and ambiguous conventional imaging modalities. In all patients a whole body scan was performed with FDG-PET in fasting patients following i.v. administration of 370-444 MBq FDG. The results were confirmed by histology and clinical evolution (follow-up period > 12 months) and imaging test. RESULTS: Prevalence of recurrence was 66.6 %. FDG-PET was positive in 40/60 patients, with confirmation in 39 cases, and 18 were true negative (TN). We have found 2 false positive and 1 false negative. Overall sensitivity, specificity, PPV, NPV and accuracy were 97.5 %, 90 %, 95.12 %, 94.7 % and 95 %, respectively. FDG-PET changed the modality of treatment in 34 patients (clinical impact 56.6 %) CONCLUSIONS: FDG-PET has high clinical impact in patients with suspicion of recurrent head and neck cancer, and should be incorporated in the diagnostic protocols before making a therapy decision.

[Patients treated for differentiated thyroid cancer with negative 131I whole-body scans and elevated thyroglobulin levels: a possible course]. / Pacientes tratados por carcinoma diferenciado de tiroides con rastreos de 131I negativos y niveles de tiroglobulina elevada. Una evolución posible.

OBJECTIVE: To verify the existence of patients with treated differentiated thyroid cancer (DTC) with negative 131I whole-body scanning (WBS) and high serum thyroglobulin (Tg) in the follow-up who evolve towards normalization without other therapy interventions. MATERIAL AND METHODS: Retrospective revision of the periodic examinations established in the protocol for patients with DTC, analyzing the levels of Tg found with IRMA annually in those with hormonal treatment and every 1-5 years in absence of previous hormonal treatment to WBS. Minimum surveillance of 2 years. Those who had elevated levels of Tg and WBS and other negative imaging tests in their course were selected. The characteristics of the patients selected were analysed in those whose Tg levels evolved to normalization without specific medical or surgical treatment (Group I) and those who did not reach normalization of Tg (Group II). RESULTS: A total of 130 patients (17.93 %) with high levels of Tg and negative WBS were detected. Group I: 31 patients (4.28 %), 11 men and 20 women; average age at the moment of the diagnosis of 33.4 years (rank: 5-60); average surveillance: 12.4 years (+/- 7.4). HISTOLOGY: 27 papillary and 4 follicular carcinoma. Average ablation dose: 3.260 GBq (88,1 mCi); average total I131 dose: 6.850 GBq (185.13 mCi). Tg normalization average time: 8.2 years. Group II: 99 patients (13.65 %), 27 men and 72 women. Average age of 40.4 years (rank: 7-76). Average surveillance: 9.8 years. HISTOLOGY: 86 papillary and 13 follicular carcinoma. Average ablation dose: 3.266 GBq (88.28 mCi); average total 131I dose: 9.363 GBq (253,06 mCi). Two of the patients in group I had negative PET-FDG. There were 13 patients in whom progressive reduction of the levels of thyroglobulin without reaching normalization with negative PET-FDG was detected. CONCLUSIONS: In patients with radiated DTC, deferred normalization of the levels of the serum thyroglobulin is possible. Empirical treatments cannot be considered the only factor that contributes to this result, which can occur without the administration of high-doses of 131I.

Usefulness of 18F-FDG PET/CT in a case of suspected vascular graft infection. / Utilidad de la 18F-FDG PET/TC en un caso de sospecha de infección de injerto vascular.

Vascular prosthetic graft infection (VPGI) is associated with high mortality and morbidity. An early and accurate diagnosis is essential in order to give the most appropriate treatment. The case is presented of a 74 year old male subjected to an aortobifemoral bypass graft, with clinical suspicion of VPGI with inconclusive tests. Later on an 18F-FDG PET/CT study showed a pathological uptake, suggestive of periprosthetic infection, as well as an incidental pulmonary lesion, suggestive of a primary neoplasm. A new 18F-FDG PET/CT showed a significant improvement in the uptake by the vascular graft after prolonged antibiotic treatment. 18F-FDG is a promising tracer for detecting VPGI as the accumulated activated white cells at the infection site have a high demand for 18F-FDG, and could help define the response to antibiotic treatment.

Role of 18F-FDG PET/CT in primary brain lymphoma. / Utilidad de la 18F-FDG PET/TC en el linfoma cerebral primario.

OBJECTIVE: To study the usefulness of 18F-FDG PET/CT in the initial evaluation and in the response assessment in primary brain lymphoma. MATERIAL AND METHODS: A retrospective analysis was carried out on 18 patients diagnosed with primary brain lymphoma, a histological subtype of diffuse large B-cell lymphoma, on whom an initial 18F-FDG PET/CT and MRI was performed, with 7 of the cases being analysed after the completion of treatment in order to assess response and clinical follow up. RESULTS: Initial 18F-FDG PET/CT showed 26 hypermetabolic foci, whereas 46 lesions were detected by MRI. The average SUV maximum of the lesions was 17.56 with T/N 3.55. The concordance of both tests for identifying the same number of lesions was moderate, obtaining a kappa index of 0.395 (P<.001). In the evaluation of treatment, MRI identified 16 lesions compared to 7 pathological accumulations observed by 18F-FDG PET/CT. The concordance of both tests to assess type of response to treatment was moderate (kappa index 0.41) (P=.04). In both the initial evaluation and the assessment of the response to treatment, PET/CT led to a change strategy in 22% of patients who had lesions outside the cerebral parenchyma. CONCLUSIONS: MRI appears to be the method of choice for detecting brain disease in patients with primary brain lymphoma, whereas 18F-FDG PET/CT seems to play a relevant role in the assessment of extra-cerebral disease.

Primary squamous cell carcinoma of the thyroid. Initial assessment and follow-up using 18F-FDG PET/CT. / Carcinoma epidermoide primario de tiroides. Valoración inicial y control evolutivo mediante 18F-FDG PET/TC.

Squamous cell carcinoma of thyroid is an uncommon, very aggressive neoplasm, having a poor prognosis and poor response to chemotherapy and radiotherapy. Surgery is the initial treatment of choice, although it often presents as a widespread disease at the time of diagnosis, usually with cervical swelling that causes most of the symptoms due to local infiltration or metastasis. Local infiltration from adjacent tumour and metastatic disease needs to be excluded from other primary epidermoid carcinomas, in order to make a correct diagnosis. This also requires the typical cytokeratin pattern seen in histological studies. The case is presented of a 53 year-old man with a medical history of hepatocarcinoma, with a cervical hypermetabolic lesion detected in an 18F-FDG PET/CT performed to exclude widespread disease. The follow-up of this lesion with this technique and its usefulness is also described.

[Evaluation of efficacy and clinical impact of FDG-PET on patients with suspicion of recurrent cutaneous melanoma]. / Evaluación de la eficacia y el impacto clínico de la PET-FDG en los pacientes con sospecha de recurrencia de melanoma maligno.

AIMS: To evaluate the efficacy and clinical impact of positron emission tomography with 18F-FDG (FDG-PET) in patients with suspected recurrent melanoma. MATERIALS AND METHODS: We studied 105 patients with melanoma and suspicion of recurrent melanoma by clinical symptoms in 38 cases or equivocal/positives morphological tests (TC, MR, US) in 77 cases. In all patients a whole body scan was performed with FDG-PET (ECAT HR +) after an intravenous injection of 444-518 MBq of 18F-FDG, in normoglucemia conditions, and previous administration of muscular relaxant, hydration and diuretic. Images were evaluated by 2 dxpert nuclear physicians and were analysed qualitatively and semiquantitatively. In 48 cases the results were confirmed by histology and clinical evolution (follow-up period >12 months) and imaging tests in 57 cases. RESULTS: Prevalence of recurrent melanoma was 63.8 %. Sensitivity, specificity, PPV, NPV and accuracy of FDG-PET was 97 %, 97.2 %, 98.5 %, 82 % y 94.7 % respectively. FDG-PET had led to a management change in 48 cases (38 %). CONCLUSIONS: FDG-PET has high clinical impact in patients with suspicion of recurrent melanoma, and should be incorporated in the diagnosis protocols, before making therapeutic decision.

[Evaluation of efficacy and clinical impact of positron emission tomography with 18F fluoro-deoxyglucose (FDG) in patients with suspicion of recurrent laryngeal carcinoma]. / Evaluación de la eficacia y el impacto clínico de la tomografía de emisión de positrones (PET) con 18F fluoro-desoxiglucosa (FDG) en pacientes con sospecha de recurrencia de carcinoma de laringe.

AIMS: To evaluate the efficacy and clinical impact of FDG-PET in patients with suspected recurrent laryngeal carcinoma. MATERIALS AND METHODS: 15 patients, with suspicion of recurrent laryngeal carcinoma and ambiguous conventional imaging modalities. In all patients a whole body scan was performed with FDG-PET in fasting patients following i.v. administration of 370-444 MBq FDG. The results were confirmed by histology and clinical evolution (follow-up period > 12 months). RESULTS: Prevalence of recurrence was 86.6%. FDG-PET was positive in 13 patients, with confirmation in all cases, and 2 were true negative (TN). Overall sensitivity, specificity, PPV, NPV and accuracy were 100%. FDG-PET changed the modality of treatment in 10 patients (clinical impact 63.3%). CONCLUSIONS: FDG-PET has high clinical impact in patients with a suspicion of recurrent laryngeal carcinoma, and should be incorporated to the diagnostic protocols before making a therapy decision.

Radioisotope synoviorthesis in paediatric and adolescent patients with haemophilia.

OBJECTIVE: To assess the outcome and adverse-effects of the radioisotope synoviorthesis in paediatric and adolescent patients with haemophilia. MATERIAL AND METHODS: Prospective study of historical cohort was conducted. A total of 20 consecutive haemophiliacs with a mean age of 13.1 years (range 4-17) were included with a mean follow-up of 64.9 months (range 18-109). The diagnosis of synovitis was established on the basis of clinical follow-up including radiological images (radiography and/or MRI). For evaluation, the classification proposed by Fernandez-Palazzi was used. INCLUSION CRITERIA: Patients aged less than 18 years old with haemophilia and more than one haemarthrosis in less than 3 months remaining a chronic synovitis despite prophylactic therapy intensification. EXCLUSION CRITERIA: Any contraindication for radionuclide synoviorthesis. Twenty-seven radioisotope synoviorthesis with (90)Y-citrate-colloid and/or (186)Re-sulphide-colloid were done. The effectiveness of the procedure was assessed through pre and posttreatment clinical comparison at 6 months after radioisotope synoviorthesis. RESULTS: Nineteen of the 27 synoviorthesis (70.3%) had a good or excellent response and 8 joints (29.7%) had partial response. It was necessary to repeat the procedure in 3 joints in 3 different patients, obtaining in all cases a good or excellent response. We appreciated inflammatory reaction after procedure in 4 cases (14.8%), which improved with analgesics and nonsteroidal anti-inflamatory drugs. None of the patients presented malignant or premalignant lesions during the follow-up. CONCLUSION: The radionuclide synoviorthesis is a very effective procedure in paediatric and adolescent patients with hemophilia, being a minimally invasive procedure, easy to perform, safe and with minimal side effects.

Role of SPECT-CT in sentinel lymph node biopsy in patients diagnosed with head and neck melanoma.

OBJECTIVE: Assess the role of SPECT-CT in sentinel lymph node (SLN) biopsy in the accurate anatomical location of the SNL in patients with cutaneous head and neck melanoma. MATERIAL AND METHODS: A retrospective study was conducted from February 2010 to June 2013 on 22 consecutive patients with a diagnosis of cutaneous head and neck melanoma (9 female, 13 male), with a mean age of 55 years old and who met the inclusion criteria for SLN biopsy. Patients underwent preoperative scanning after peri-scar injection of (99m)Tc-labeled-nanocolloid. Planar images of the injection-site, whole-body, and SPECT-CT scanning were acquired. RESULTS: Detection rate of SLN reached up to 91% (20/22 patients) by planar lymphoscintigraphy and 95.4% (21/22 patients) by SPECT-CT. SPECT-CT provided an accurate location of SLN in 14/22 patients, enabling to improve the surgical approach (clinical impact: 63.6%). SLN was positive for metastatic cells in 9.1% patients. CONCLUSION: SPECT-CT provides detailed anatomical SLN location and allows detecting a higher number of SLN than planar lymphoscintigraphy. Routine use of SPECT-CT is recommended in order to optimise the SLN detection and location in patients with head and neck melanoma.

[F-18-fluordeoxyglucose positron emission tomography on patients with differentiated thyroid cancer who present elevated human serum thyroglobulin levels and negative I-131 whole body scan]. / PET con 18FDG en pacientes con cáncer diferenciado de tiroides que presentan niveles elevados de tiroglobulina sérica y rastreos con 131I negativos.

UNLABELLED: This study aimed to evaluate the role of Fluorine-18-fluorodeoxyglucose positron emission tomography (PET-FDG) in patients with elevated serum thyroglobulin (hTg) levels where thyroid cancer tissue does not concentrate radioiodine, rendering false-negative results on I-131 scanning. MATERIAL AND METHODS: Whole-body PET imaging using FDG was performed in 54 patients (37 female, 17 male) aged 17-88 years: 45 with papillary tumors and 9 with follicular tumors who were suspected of having recurrent thyroid carcinoma due to elevated thyroglobulin levels (hTg > 2 ng/ml) under thyroid-stimulating hormone (TSH > or = 30 microIU/ml) in whom the iodine scan was negative. All whole body scans were obtained with diagnostic doses (185 MBq). Whole body PET imaging was performed in fasting patients following i.v. administration of 370 MBq FDG while the patients were receiving full thyroid hormone replacement. Before PET, 99mTc methoxyisobutylisonitrile scintigraphy (99mTc-MIBI) was done in 14 patients and morphologic imaging in 26 by CT scan. RESULTS: Positive PET results confirmed the presence of hypermetabolic foci in 25/54 patients (46.29 %). Positive findings were found for PET-FDG in patients with hTg levels higher than 10 ng/ml receiving full thyroid hormone replacement. 99mTc-MIBI demonstrated lesions in 7/14 patients (50 %). PET-FDG and 99mTc-MIBI had congruent positive results in 4/7 patients. All the lesions found by CT were detected by PET-FDG, while recurrent disease was found in 12/21 patients with previous negative CT. CONCLUSIONS: These results suggest that PET-FDG seems to be a promising tool in the follow-up of thyroid cancer and should be considered in patients suffering from differentiated thyroid cancer with suspected recurrence and/or metastases by elevated thyroglobulin levels, and negative I-131 whole body scans. PET-FDG might be more useful at hTg levels > 10 ng/ml.

Sentinel lymph node biopsy in paediatric melanoma. A case series.

The incidence of melanoma in children is uncommon, being particularly rare in children under 10 years-old. However, this disease is increasing by a mean of 2% per year. As in adults, the lymph node status is the most important prognostic factor, crucial to performing the selective sentinel lymph node biopsy (SLNB). We report 3 cases of paediatric patients of 3, 4 and 8 years-old, in which SLNB was performed for malignant melanoma. Paediatric age implies greater technical difficulty to the scintigraphy scan due to poor patient cooperation, with mild sedation required in some cases, and only being able to acquire planar images in other cases. SPECT/CT was only performed in the oldest patient. In our cases, SLNB was useful for selecting the least invasive surgery in order to reduce morbidity.