Imaging for Radiation Planning in Breast Cancer.

Radiation therapy is an integral component of the treatment of breast cancer. The indications and type of radiation therapy vary depending on disease invasiveness and stage. Imaging is the cornerstone for radiation therapy planning. While conventional imaging with CT remains the primary modality for radiation treatment planning locally in the breast, molecular imaging with [18F]FDG-PET/CT identifies additional occult disease that may help alter the local radiation therapy plan or treat oligometastatic disease. The ultimate effects on long-term outcomes remain to be determined. This article reviews the role of imaging in radiation planning for breast cancer.

Extraprostatic Uptake of 18F-Fluciclovine: Differentiation of Nonprostatic Neoplasms From Metastatic Prostate Cancer.

OBJECTIVE. Fluciclovine is a synthetic radiolabeled amino acid analog used for imaging of biochemical recurrent prostate cancer. Uptake of fluciclovine is mediated by several amino acid transporters, including alanine-serine-cysteine transporter 2 and large neutral amino acid transporters, which are known to be overexpressed in other malignancies. CONCLUSION. Knowledge of the common patterns of prostate cancer recurrence, in addition to what other neoplasms can show uptake, is critical for accurate study interpretation.

Extraosseous Colonic Uptake of 99mTc-MDP Associated With Iodinated Contrast CT.

Extraosseous Tc-MDP uptake on bone scans is frequently encountered and has a broad differential diagnosis. A small subset of such patients can present with intestinal Tc-MDP uptake. We present the case of a 35-year-old woman with status after right nephrectomy for renal cell carcinoma, being followed with bone scan for osseous metastases. Follow-up imaging revealed new faint Tc-MDP uptake in the right hemiabdomen. Correlation with contrast-enhanced CT localized this uptake to the ascending colon. Enteric Tc-MDP uptake and its association with iodinated contrast should be considered in the differential diagnosis of extraosseous enteric Tc-MDP uptake.

Guidance on 177Lu-DOTATATE Peptide Receptor Radionuclide Therapy from the Experience of a Single Nuclear Medicine Division.

177Lu-DOTATATE is a radiolabeled somatostatin analog that has been approved by the U.S. Food and Drug Administration (FDA) for the treatment of somatostatin receptor-positive gastroenteropancreatic neuroendocrine tumors in adults. Radionuclide therapies have been administered for many years within nuclear medicine departments in North America. However, in comparison to other radiotherapies, 177Lu-DOTATATE peptide receptor radionuclide therapy involves more planning, coordination, concomitant medication administration (antiemetic medications and amino acids), and direct patient care. To date, various methods have been used in multiple centers during the NETTER-1 trial and the provision of patient care. As participants in the phase 3 NETTER-1 trial and the subsequent expanded-access program for the administration of 177Lu-DOTATATE studies, as well as recently starting postapproval clinical care, we have administered 61 177Lu-DOTATATE therapies at the time of this manuscript submission (13 in the NETTER-1 trial, 39 in the expanded-access program, and 9 clinically) at the Dana-Farber Cancer Institute and here share our procedures, personnel training, and workflow to help other centers establish programs for this FDA-approved 177Lu-DOTATATE peptide receptor radionuclide therapy.

Postradiation changes in tissues: evaluation by imaging studies with emphasis on fluorodeoxyglucose-PET/computed tomography and correlation with histopathologic findings.

Efforts have been made to minimize the damage to adjacent normal tissues during radiotherapy, primarily by shifting from the use of conventional radiotherapy to more advanced techniques. Reviewing the overall pattern on combined anatomic and functional imaging can enhance diagnostic accuracy. Several radiotracers can be used; [(18)F]fluorodeoxyglucose is the most common. Familiarity with the type and timing of previous radiation therapy, the spectrum of imaging findings after radiation injury, and the appropriate use of the different radiotracers can be crucial. This article summarizes postradiation histologic findings and multimodality imaging findings, with emphasis on PET/computed tomography.

End-therapy positron emission tomography for treatment response assessment in follicular lymphoma: a systematic review and meta-analysis.

PURPOSE: Use of 2[(18)F]fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) in postchemotherapy response assessment in follicular lymphoma is still a controversial issue. Here, we conducted the first systematic review and meta-analysis to determine the predictive value of FDG-PET in predicting outcome after chemotherapy of follicular lymphoma. EXPERIMENTAL DESIGN: Comprehensive literature search in Ovid-MEDLINE and EMBASE databases was performed to identify studies which evaluate predictive value of end-therapy PET and/or computed tomography (CT) in patients with follicular lymphoma. To quantitatively compare the predictive value of PET and CT, pooled hazard ratios (HRs) comparing progression-free survival (PFS) between patients with positive and negative results were adopted as the primary indicators for meta-analysis. To explore the efficiency in determining complete remission (CR), pooled CR rates of PET- and CT-based response criteria were calculated. Pooling of these parameters was based on the random-effects model. RESULTS: Review of 285 candidate articles identified eight eligible articles with a total of 577 patients for qualitative review and meta-analysis. The pooled HRs of end-therapy PET and CT were 5.1 [95% confidence interval (CI), 3.7-7.2] and 2.6 (95% CI, 1.2-5.8), respectively, which implies that PET is more predictive of PFS after chemotherapy than CT. The pooled CR rates of PET- and CT-based response criteria were 75% (95% CI, 70-79%) and 63% (95% CI, 53-73%), respectively, which implies that PET is more efficient in distinguishing CR (without residual disease) from other states with residual disease. In addition, qualitative systematic review indicates the same findings. CONCLUSIONS: Consistent evidence favoring PET-based treatment assessment should be considered in the management of patients with follicular lymphoma.

Positron emission tomography/computed tomography imaging in Merkel cell carcinoma: a study of 270 scans in 97 patients at the Dana-Farber/Brigham and Women's Cancer Center.

BACKGROUND: Merkel cell carcinoma (MCC) is a rare and lethal cutaneous neuroendocrine carcinoma. Imaging is crucial for accurate staging, which remains a strong predictor of survival, as well as earlier detection of recurrence and progression, which are common despite aggressive management. There is no consensus on the role of initial and subsequent imaging for MCC. OBJECTIVE: We sought to evaluate the use of 2-fluoro-[(18)F]-deoxy-2-D-glucose (FDG)-positron emission tomography (PET)/computed tomography (CT) in the management of MCC. METHODS: In all, 270 FDG-PET/CT studies were performed in 97 patients with pathology-proven MCC at the Dana-Farber/Brigham and Women's Cancer Center, Boston, Mass, from August 2003 to December 2010. RESULTS: FDG-PET/CT scans were obtained as part of the initial (61 scans in 61 patients) and subsequent (209 scans in 79 patients) treatment strategies. MCCs were FDG-avid with a mean maximum standardized uptake value of primary lesions of 6.5 (range 1.3-12.9) and a mean maximum standardized uptake value of regional and distant metastases of 7.2 (range 1.5-9.9). FDG-PET/CT upstaged 16% of patients who underwent baseline scans. FDG-PET/CT studies showed that bone and bone-marrow metastases were more common than previously reported, and were often undetected by CT. LIMITATIONS: Our study is limited by its retrospective design, and potential referral bias associated with a tertiary care center. CONCLUSIONS: FDG-PET/CT performed as part of the initial management strategy tended to upstage patients with more advanced disease. FDG-PET/CT performed as part of the subsequent treatment strategy identified metastatic disease, particularly in bone/bone marrow, which was not seen on CT. FDG-PET/CT imaging is a valuable staging and restaging tool in MCC management.