Performance of FDG PET/CT at initial diagnosis in a rare lymphoma: nodular lymphocyte-predominant Hodgkin lymphoma.

PURPOSE: Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is a rare Hodgkin lymphoma distinguished from classical Hodgkin lymphoma (cHL) by the nature of the neoplastic cells which express B-cell markers. We wanted to determine the diagnostic performance of FDG PET/CT in initial assessment and its therapeutic impact on staging. METHODS: We retrospectively studied a population of 35 patients with NLPHL (8 previously treated for NLHPL, 27 untreated). All patients underwent an initial staging by pretherapeutic FDG PET/CT. The impact on initial stage or relapse stage was assessed by an independent physician. RESULTS: In a per-patient analysis, the sensitivity of the pretherapeutic FDG PET/CT was 100%. In a per-site analysis, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of pretherapeutic FDG PET/CT were 100%, 99%, 97%, 100% and 99%, respectively. Pretherapeutic FDG PET/CT led to a change in the initial stage/relapse stage in 12 of the 35 patients (34%). In contrast to previous results established without FDG PET/CT, 20% of patient had osteomedullary lesions. CONCLUSION: Pretherapeutic FDG PET/CT has excellent performance for initial staging or relapse staging of NLPHL.

Additional diagnostic value of hybrid SPECT-CT systems imaging in patients with differentiated thyroid cancer.

AIM: : Nuclear medicine has entered a new era of multimodality imaging. Single-photon emission computed tomography/computed tomography (SPECT/CT) hybrid cameras are relatively new diagnostic tools that have been widely adopted and are present in most nuclear medicine units. SPECT/CT instruments allow functional and morphologic images to be acquired as superimposed (fusion images) in a single session. METHODS: The integration of CT enables better characterization of functional abnormalities identified on planar and SPECT scintigraphy by offering structural information. It thus highly improves accuracy compared with conventional scintigraphy. RESULTS AND CONCLUSIONS: The combination of functional information and anatomic localization has the potential to influence medical practice with newer imaging algorithms. This review presents the current evidence and potential indications of SPECT/CT imaging in the initial staging, treatment, and follow-up of patients with differentiated thyroid cancer.

Impact of [(18)F]fluorodeoxyglucose positron emission tomography response evaluation in patients with high-tumor burden follicular lymphoma treated with immunochemotherapy: a prospective study from the Groupe d'Etudes des Lymphomes de l'Adulte and GOELAMS.

PURPOSE: [(18)F]Fluorodeoxyglucose positron emission tomography (PET) is widely used for the staging and restaging of patients with aggressive lymphoma, but less is known about the utility of PET in patients with follicular lymphoma (FL). In a prospective study, we evaluated the prognostic value of PET performed during treatment and at the end of treatment in 121 patients with FL treated with first-line immunochemotherapy. PATIENTS AND METHODS: Patients with previously untreated high-tumor burden FL were treated with six cycles of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) plus two cycles of rituximab, without rituximab maintenance. PET was performed before treatment, after four cycles of R-CHOP (interim PET), and at the end of treatment (final PET). PET scans were centrally reviewed. RESULTS: The total number of patients included was 121. Median age was 57 years. After central review, interim PET (n = 111) was negative in 76% of patients, and final PET (n = 106) was negative in 78%. With a median follow-up of 23 months, 2-year progression-free survival rates were 86% for interim PET-negative versus 61% for interim PET-positive patients (P = .0046) and 87% for final PET-negative versus 51% for final PET-positive patients (P < .001), respectively. Two-year overall survival also significantly differed according to final PET results: 100% versus 88% (P = .0128). CONCLUSION: PET performed either after four cycles of R-CHOP or at the end of therapy was strongly predictive of outcome in this prospective study. Therapeutic intervention based on PET results during or after inductive treatment should be evaluated.

Triple-negative breast cancer: early assessment with 18F-FDG PET/CT during neoadjuvant chemotherapy identifies patients who are unlikely to achieve a pathologic complete response and are at a high risk of early relapse.

UNLABELLED: Triple-negative breast cancer, an aggressive subtype, represents 15% of invasive breast tumors. This prospective study investigated whether early changes in (18)F-FDG tumor uptake during neoadjuvant chemotherapy (NAC) can predict outcomes. METHODS: Twenty (M0) patients underwent (18)F-FDG PET/CT at baseline and after the second cycle. NAC was continued irrespective of PET results. RESULTS: At surgery, 6 patients had a pathologic complete response, whereas 14 had residual tumor. Four patients showed early relapse (in the 2 y after surgery). There were 11 metabolic responders and 9 nonresponders using a 42% decrease in maximum standardized uptake value as a cutoff. In nonresponding patients, the risk of residual tumor at surgery was 100% (vs. 45% in responders; P = 0.014), and the risk of early relapse was 44% (vs. 0%; P = 0.024). CONCLUSION: A less than 42% decrease in (18)F-FDG uptake at 2 cycles means residual tumor at the end of NAC and a high risk of early relapse.

Lymphoscintigraphy can select breast cancer patients for internal mammary chain radiotherapy.

PURPOSE: Given the risk of undesired toxicity, prophylactic internal mammary (IM) chain irradiation should be offered only to patients at high risk of occult involvement. Lymphoscintigraphy for axillary sentinel node biopsy might help in selecting these patients. METHODS AND MATERIALS: We reviewed published studies with the following selection criteria: ≥ 300 breast cancer patients referred for axilla sentinel node biopsy; scintigraphy performed after peritumoral or intratumoral tracer injection; IM biopsy in the case of IM drainage; and axilla staged routinely independent of IM status. RESULTS: Six prospective studies, for a total of 3,876 patients, fulfilled the inclusion criteria. Parasternal drainage was present in 792 patients (20.4%). IM biopsy was performed in 644 patients and was positive in 111 (17.2%). Of the positive IM biopsies, 40% were associated with tumors in the lateral breast quadrants. A major difference in the IM positivity rate was found according to the axilla sentinel node status. In patients with negative axilla, the IM biopsy was positive in 7.8% of cases. In patients with positive axilla, however, the IM biopsy was positive in 41% (p < .00001). Because biopsy of multiple IM hot nodes is difficult, the true risk could be even greater, probably close to 50%. CONCLUSIONS: Patients with IM drainage on lymphoscintigraphy and a positive axilla sentinel node have a high risk of occult IM involvement. These women should be considered for IM radiotherapy.

The yield of 18F-FDG PET/CT in patients with clinical stage IIA, IIB, or IIIA breast cancer: a prospective study.

UNLABELLED: The purpose of this study was to prospectively evaluate the role of (18)F-FDG PET/CT in patients with stage IIA, IIB, or IIIA breast cancer. METHODS: During 56 mo, 131 consecutive patients with large (>2 cm) breast cancer and clinical stage IIA, IIB, or IIIA (based on clinical examination, mammography, breast MRI, and ultrasonography) underwent (18)F-FDG PET/CT. The nuclear physician was unaware of the results of any other procedure (bone scan, chest radiography, liver ultrasound, or thoracoabdominal CT scan). RESULTS: Of the 131 examined patients, 36 had clinical stage IIA (34 T2N0 and 2 T1N1), 48 stage IIB (20 T3N0 and 28 T2N1), and 47 stage IIIA (29 T3N1, 9 T2N2, and 9 T3N2). (18)F-FDG PET/CT modified staging for 5.6% of stage IIA patients, for 14.6% of stage IIB patients, and for 27.6% of stage IIIA patients. However, within stage IIIA, the yield was specifically high among the 18 patients with N2 disease (56% stage modification). When considering stage IIB and primary operable IIIA (T3N1) together, the yield of (18)F-FDG PET/CT was 13% (10/77); extraaxillary regional lymph nodes were detected in 5 and distant metastases in 7 patients. In this series, (18)F-FDG PET/CT outperformed bone scanning, with only 1 misclassification versus 8 for bone scanning (P = 0.036). CONCLUSION: (18)F-FDG PET/CT provided useful information in 13% of patients with clinical T3N0, T2N1, or T3N1 disease. The yield was more modest in patients with stage IIA. The high yield in the case of N2 disease demonstrates that stage IIIA comprises 2 quite distinct groups of patients.