Radiotherapy of Hodgkin and Non-Hodgkin Lymphoma: A Nonrigid Image-Based Registration Method for Automatic Localization of Prechemotherapy Gross Tumor Volume.

PURPOSE: To improve the contouring of clinical target volume for the radiotherapy of neck Hodgkin/non-Hodgkin lymphoma by localizing the prechemotherapy gross target volume onto the simulation computed tomography using [18F]-fluorodeoxyglucose positron emission tomography/computed tomography. MATERIAL AND METHODS: The gross target volume delineated on prechemotherapy [18F]-fluorodeoxyglucose positron emission tomography/computed tomography images was warped onto simulation computed tomography using deformable image registration. Fifteen patients with neck Hodgkin/non-Hodgkin lymphoma were analyzed. Quality of image registration was measured by computing the Dice similarity coefficient on warped organs at risk. Five radiation oncologists visually scored the localization of automatic gross target volume, ranking it from 1 (wrong) to 5 (excellent). Deformable registration was compared to rigid registration by computing the overlap index between the automatic gross target volume and the planned clinical target volume and quantifying the V95 coverage. RESULTS: The Dice similarity coefficient was 0.80 ± 0.07 (median ± quartiles). The physicians' survey had a median score equal to 4 (good). By comparing the rigid versus deformable registration, the overlap index increased from a factor of about 4 and the V95 (percentage of volume receiving the 95% of the prescribed dose) went from 0.84 ± 0.38 to 0.99 ± 0.10 (median ± quartiles). CONCLUSION: This study demonstrates the impact of using deformable registration between prechemotherapy [18F]-fluorodeoxyglucose positron emission tomography/computed tomography and simulation computed tomography, in order to automatically localize the gross target volume for radiotherapy treatment of patients with Hodgkin/non-Hodgkin lymphoma.

Fluorodeoxyglucose positron emission tomography in pulmonary carcinoid tumors.

AIM: The role of fluorodeoxyglucose positron emission tomography (FDG-PET) as an additional investigation to computer tomography for pulmonary carcinoid tumors remains controversial. The aim of this study was to assess the role of FDG-PET for the diagnosis and staging of pulmonary carcinoid tumors. METHODS: We performed a retrospective mono-institutional analysis of data from 97 patients with pathologically confirmed pulmonary carcinoid tumor who had been operated on between July 1998 and April 2009 and had had a preoperative FDG-PET scan performed. RESULTS: Sixty-five (67%) of the 97 tumors were typical (TC) and 32 (33%) atypical (AC) carcinoid tumors. Overall FDG-PET sensitivity was 67% being lower for TC (60%) than for AC (81%) (P=0.04). FDG-PET negative tumors were smaller than FDG-PET positive tumors, with a respective median size of 15 and 17 mm (P=0.02). Median SUVmax for FDG-PET-positive tumors was 4.0 (2.8-5.1) with no difference between TC and AC tumors. Median Ki-67 expression was respectively 4.7% and 3.1% for FDG-PET positive and FDG-PET negative tumors (P=0.05). During a median follow-up of 49 months (interquartile range 30-63 months), 9 patients (4TC, 5AC) developed recurrent disease. Neither SUVmax nor Ki-67 expression resulted associated with disease-free survival. CONCLUSION: With an overall sensitivity of 67%, FDG-PET has shown to be useful in the preoperative work-up of patients with suspect lung carcinoid tumors. In particular it could have a role in larger tumors. These results warrant a prospective evaluation of FDG-PET in the staging of lung carcinoid tumor.

Lymphoscintigraphy in clinical routine practice: reproducibility and accuracy in melanoma patients with a long-term follow-up.

INTRODUCTION: The sentinel node status is the most important single factor determining overall survival for patients with localized melanoma. Preoperative lymphoscintigraphy (LS) is essential in locating the correct sentinel lymph node (SN) and the reproducibility of the method determines the accuracy of the sentinel node biopsy (SNB). This study aims at determining the reproducibility and accuracy of LS in routine clinical practice after long-term follow-up. PATIENTS AND METHODS: One hundred and eight melanoma patients with clinically unpredictable lymphatic drainage were prospectively enrolled to undergo two LS. The first LS was performed to determine the site and number of the lymphatic basins to plan SNB anesthesia and the second preoperative LS was to allow SN localization intra-operatively. RESULTS: Lymphatic drainage was demonstrated in all patients. In 84 of 108 cases, both LSs were concordant in terms of site and number of nodal basins visualized. After a median follow-up of 80 months, no nodal recurrence was observed in the five patients with a decreased number of lymph node basins. In the group with increased number of lymph node basins, one patient developed nodal metastases in the same regional lymph node basin visualized by both LS studies. CONCLUSION: LS is an accurate and reproducible method to determine the localization of the sentinel node in the day-to-day routine to clinical practice when primary melanoma is also located in body sites with variable lymphatic drainage.

An unusual breast lesion: the ultrasonographic, mammographic, MRI and nuclear medicine findings of mammary hibernoma.

We report the case of a 42-year-old woman being treated for an ovarian cancer who was diagnosed at the age of 40. A CT-positron emission tomography (PET) scan performed as follow-up documented abnormal uptake in the right breast. Mammograms were negative for malignancy, while a focal hyperechoic lesion was observed on ultrasonography in the same breast. Thus, she was referred to our institution for breast MRI, which showed a focal area of enhancement with atypical features. Percutaneous biopsy was performed, and a mammary hibernoma was diagnosed. Radiological and pathological correlation was provided. To our knowledge, this is the only report that describes the features of this rare tumour on four different imaging modalities (mammography, ultrasonography, MRI and CT-PET).

Peritoneal carcinomatosis from ovarian cancer: the role of CT and [¹8F]FDG-PET/CT.

PURPOSE: The diagnosis of peritoneal carcinomatosis secondary to ovarian cancer is a real challenge in the cancer imaging field. In this retrospective study, we evaluate the accuracy of Single Detector Computed Tomography (SDCT), Multi Detector Computed Tomography (MDCT), and Positron Emission Tomography-Computed Tomography with F18-fluorodeoxyglucose ([¹8F]FDG-PET/CT) in the diagnosis of peritoneal seeding and we evaluate the possible applications of MDCT to predict the complete surgical removal of the peritoneal deposits. METHODS AND MATERIALS: A total of 228 scans (91 SDCT, 89 MDCT, and 48 [¹8F]FDG-PET/CT) of patients with peritoneal carcinomatosis secondary to ovarian cancer proved at laparoscopy and confirmed by histopathology were retrospectively reviewed by two independent groups of Radiologists and Nuclear Medicine Physicians for the evaluation of ascites, peritoneal nodules, and omental cake signs. RESULTS: MDCT showed 81% of true positives, SDCT 72.5%, and [¹8F]FDG-PET/CT 77%. False negatives were 19% for MDCT, 27.5% for SDCT, and 23% for [¹8F]FDG-PET/CT. CONCLUSION: From our results, we concluded that MDCT is the technique of choice in the diagnosis of peritoneal seeding, while [¹8F]FDG-PET/CT, though showing similar accuracy, remains the most accurate technique for monitoring therapeutic response and disease recurrence. MDCT could play an important role due to its ability to predict the possibility of complete surgical removal of disease thus influencing the treatment plan aimed to improve quality of life.

Carcinoma, tuberculosis and elastofibroma in one patient: is [18F]FDG-PET/CT helpful?

We present the case of a woman with persistent dorsal pain and two solid lung lesions documented on multidetector CT which showed concomitant [18F]FDG uptake. One of the lesions proved to be adenocarcinoma at biopsy and presented a lower [18F]FDG uptake when compared to the second lesion, which was smaller in size, and was postsurgically diagnosed as tuberculoma. This case portrays the paradoxical metabolic behaviour of two lesions, leading to misdiagnosis and erroneous disease staging in an oncology patient. Incidentally, the patient also had an elastofibroma dorsi, a rare benign tumour which can also be a possible source of false results in the PET exam. We provide explanations and possible solutions to these findings in order to familiarise the physician with them, and optimise patient management.

Carcinoma, tuberculosis and elastofibroma in one patient: is [18F]FDG-PET/CT helpful?

We present the case of a woman with persistent dorsal pain and two solid lung lesions documented on multidetector CT which showed concomitant [18F]FDG uptake. One of the lesions proved to be adenocarcinoma at biopsy and presented a lower [18F]FDG uptake when compared to the second lesion, which was smaller in size, and was postsurgically diagnosed as tuberculoma. This case portrays the paradoxical metabolic behaviour of two lesions, leading to misdiagnosis and erroneous disease staging in an oncology patient. Incidentally, the patient also had an elastofibroma dorsi, a rare benign tumour which can also be a possible source of false results in the PET exam. We provide explanations and possible solutions to these findings in order to familiarise the physician with them, and optimise patient management (AU)

Se presenta el caso de una mujer con dorsalgia persistente y 2 lesiones pulmonares de carácter sólido visualizadas en tomografía computarizada multidetector. Dichas lesiones mostraban concomitantemente captación de [18F]FDG. Una de las lesiones se diagnosticó de adenocarcinoma tras la biopsia, y presentaba una captación de [18F]FDG de menor intensidad que la mostrada por la segunda lesión, de menor tamaño, y que tras la cirugía se diagnosticó como tuberculoma. Este caso demuestra cómo el comportamiento metabólico paradójico de 2 lesiones puede suponer un diagnóstico y estadificación oncológico erróneo. Incidentalmente, la paciente también se vio afectada de un elastofibroma dorsi, un tumor benigno poco frecuente, que puede ser, a su vez, causa de falsos positivos en el examen PET (tomografía por emisión de positrones). Con este caso se pretende ofrecer razonamientos y posibles soluciones a estos hallazgos, así como familiarizar al médico con estas entidades para optimizar el tratamiento del paciente oncológico (AU)

Role of multidetector CT and FDG-PET/CT in the diagnosis of local and distant recurrence of resected rectal cancer.

PURPOSE: The aim of this study was to compare the diagnostic value of multidetector computed tomography (MDCT) and F18-fluorodeoxyglucose positron emission tomography-computed tomography (FDG-PET/CT) for the detection of local and distant recurrence in patients operated on for rectal cancer. MATERIALS AND METHODS: Sixty-seven patients who underwent radical surgery for rectal cancer and were followed up with FDG-PET/CT and MDCT were included in this retrospective study. The FDG-PET/CT and MDCT findings were independently compared with histological sampling or 2 years' follow-up. RESULTS: Local recurrence occurred in 15/67 patients. MDCT diagnosed local recurrence in 15/15 cases and FDG-PET/CT in 14/15. Sensitivity and specificity were 100% and 98% for MDCT and 93% and 98% for FDG-PET/CT, respectively. Hepatic lesions were found in 17/67 patients. All hepatic metastases were detected by both techniques. Pulmonary metastases occurred in 8/67 patients: they were correctly identified in all cases by MDCT and in 6/8 by FDG-PET/CT. CONCLUSIONS: MDCT and FDG-PET/CT showed high sensitivity and specificity for the detection of local recurrence of rectal cancer. Both techniques were equally accurate for the detection of hepatic metastases. MDCT showed slightly higher sensitivity and positive predictive value in detecting pulmonary metastases compared with FDG-PET/CT.

Lymphatic mapping to tailor selective lymphadenectomy in cN0 tongue carcinoma: beyond the sentinel node concept.

PURPOSE: Cervical lymph node status is the most important pathological determinant of prognosis and decision making in head and neck squamous cell carcinoma (SCC). The aim of this study was to demonstrate that lymphoscintigraphy (LS) can supply a complete map of the lymphatic drainage before surgery, allowing planning of the type of intervention and serving to guide lymphadenectomy. METHODS: The study population comprised 14 patients with T2-4 SCCs of the tongue and clinically negative lymph nodes in the neck (cN0) who were scheduled to undergo tumour resection and selective level I-IV neck dissection extended to level V. LS was performed in all patients following the injection of (99m)Tc-colloidal sulphide in three aliquots around the primary lesion. Dynamic, static and tomographic images of the head and neck were acquired. The operative specimens were subjected to lymphoscintigraphic evaluation. Preoperative and postoperative imaging results were compared with the pathological findings. All nodes were examined using haematoxylin-eosin staining. RESULTS: Preoperative LS was successful in all patients. Preferential pathways of lymphatic drainage were identified: level II of the neck was the most common lymphatic drainage pattern, followed by levels IV and III. Contralateral drainage occurred in 11 patients and in two of them metastatic nodes were found on the contralateral side. Metastases were observed only in radioactive lymph nodes. CONCLUSION: LS is able to supply a complete map of the lymphatic drainage before surgery, making it possible to tailor selective neck dissection to each individual patient based on the results of preoperative mapping, thereby sparing healthy lymphatic tissue and reducing surgery-related morbidity.