Brentuximab vedotin as frontline treatment for HIV-related extracavitary primary effusion lymphoma.

Primary effusion lymphoma (PEL) is a rare and aggressive herpesvirus-8 (HHV-8) driven B cell non-Hodgkin's lymphoma (NHL) that is usually associated with human immunodeficiency virus (HIV) infection, and has a poor prognosis. PEL is comprised of two clinically distinct but pathologically similar variants: classic and extracavitary PEL. Based on retrospective series, treatment options include combined antiretroviral therapy (cART) in conjunction with chemotherapy regimens used in other forms of NHLs. Treatment outcomes with this approach are usually dismal and there is no standard of care. We present a case of a patient with HIV associated CD30+ extracavitary PEL unfit for multi-agent chemotherapy, who achieved a durable complete response with single agent brentuximab-vedotin and cART.

Biopsy of suspicious bone lesions in patients with a single known malignancy: prevalence of a second malignancy.

OBJECTIVE: The probability that a suspicious bone lesion in a patient with one known malignancy is actually due to a second, previously unknown primary malignancy has been reported to be 2-8%. We sought to determine this prevalence as well as that of benign diagnoses in a larger number of patients in a tertiary cancer center. MATERIALS AND METHODS: The medical records of 482 consecutive patients (254 women and 228 men) with only one known primary malignancy each (excluding nonmelanoma skin cancer) and who underwent biopsy of a suspicious bone lesion were retrospectively reviewed. The results of bone biopsy were classified as benign, metastasis of the known primary malignancy, due to a second primary malignancy, or nondiagnostic or indeterminate. RESULTS: In 103 of 482 (21%) patients, bone biopsy results were benign, 316 (66%) were due to metastases of the known malignancy, 15 (3%) were due to a second malignancy, and 48 (10%) were nondiagnostic or indeterminate. Second malignancies included osteosarcoma (n = 4); soft-tissue sarcoma (n = 2); lymphoma (n = 2); plasma cell malignancy (n = 2); and lung cancer, thyroid cancer, renal cancer, chondrosarcoma, and carcinoma of unknown primary (n = 1 each). CONCLUSION: In 3% of patients with one known malignancy and a suspicious bone lesion, the lesion was due to a previously unknown second malignancy; in 21% of patients, the lesion was benign. Bone biopsy is recommended in the management of patients with one known cancer and a suspicious bone lesion only if the presence of a second malignancy would alter clinical management.

PET/CT image fusion error due to urinary bladder filling changes: consequence and correction.

OBJECTIVE: A considerable change of urinary bladder (UB) shape in PET compared with CT in integrated PET/CT system is frequently noted. This study initially evaluated this finding with and without oral contrast (OC) use. In addition, a one bed pelvic section (PLV) repeat acquisition was investigated as a solution to this problem. METHODS: (18)FDG PET/CTs of 88 patients were analyzed. OC was administered in 68 patients, of whom 31 had PLV images taken 5-10 min later. Three-dimensional mid-UB CT and PET matching measurements were compared. In addition, UB walls displacement between CT and PET were analyzed. RESULTS: The mean UB height was significantly increased (P < 0.001) in PET when compared with CT, both anteriorly and posteriorly; however, UB width and depth were not significantly different. An upward shift of superior UB wall in PET from equivalent CT images was noted, whereas there was no appreciable displacement of the other UB walls. The percent UB height increase on PET from CT was significantly greater with than without OC use. The UB height difference between PET and CT was markedly reduced on PLV when compared with the original scans. CONCLUSIONS: Caution should be exerted during the interpretation of PET/CT scans of the pelvis as there is significant upward expansion of UB on PET compared with CT that appears to be exaggerated by OC use, likely due to additional fluid load. The PET/CT fusion errors of UB can be substantially resolved through a separate PLV acquisition presumably due to the shorter time interval of UB scan completion between CT and PET.

Value of precise localization of recurrent multiple myeloma with F-18 FDG PET/CT.

A 37-year-old man with multiple myeloma in remission underwent routine fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) study for disease restaging. Both FDG-PET and CT images showed focal abnormalities in the region of the T6 vertebra, but the fused images that are routinely provided with PET/CT could precisely localize the FDG active lesion to a soft tissue focus in the epidural space, away from a lytic nonactive vertebral body lesion despite their close proximity. The PET/CT scan identified a few other metabolically active osseous lesions out of many lytic bony changes throughout the skeleton. Accordingly, the patient received the correct management for an impending spinal cord compression at the appropriate time, in addition to systemic therapy for disease relapse.

Evaluation of different methods of 18F-FDG-PET target volume delineation in the radiotherapy of head and neck cancer.

OBJECTIVE: To quantify differences between the alternative methods of F-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET)-based delineation of the gross tumor volume in patients with head and neck cancer. MATERIALS AND METHODS: Twelve patients with locally-advanced head and neck carcinomas were studied. The reference gross tumor volume (GTVref) was established by a radiation oncologist, along with a neuroradiologist, using the computed tomography-simulation and diagnostic magnetic resonance imaging data. With the GTVref obscured, a second radiation oncologist and a nuclear medicine physician determined the following contours: (1) high FDG uptake based on visual inspection (GTVvis), (2) the contour derived from the 50% maximum standardized uptake value (SUV) threshold (GTV50), (3) the contour derived from a 2.5 SUV absolute threshold (GTV2.5), and (4) the contours derived from an iterative segmentation algorithm (GTViter). These volumes were compared with the GTVref using a signed-ranks test with the exact reference distribution. RESULTS: The average GTVref was 75.5 mL (median 72.8 mL, range 22.2-138.4 mL). The average GTVvis was 57.6 (median 55.4 mL, range 12-115.8 mL). Overall, a 21% reduction in volume size was observed with GTVvis versus GTVref. When the signed-ranks test with the exact reference distribution was applied, the difference was not statistically significant (P = 0.32). The average GTV2.5 was 60 mL (median 64.5, range 8.8-90.3 mL). The differences between GTV2.5 and GTVref were not statistically significant (P = 0.35). The use of GTV50 and GTViter produced significantly smaller volumes with respect to GTVref (P < 0.005). CONCLUSIONS: PET-based tumor volumes are strongly affected by the choice of threshold level. Quantitatively, GTVs derived from visual inspection of the region of high FDG uptake do not significantly differ from GTVref in this cohort of patients. The inclusion of alternative FDG-PET segmentation data, other than visual inspection, may reduce target volumes significantly.

Impact of PET/CT in comparison with same day contrast enhanced CT in breast cancer management.

PURPOSE: To evaluate the impact of F-18 fluorodeoxyglucose (FDG) positron emission tomography with fused computerized tomography (PET/CT) in comparison with same day contrast enhanced CT (CE-CT) in breast cancer management. METHOD: Seventy studies in 49 breast cancer patients, 17 for initial and 53 for restaging disease were included. All patients underwent PET/CT for diagnostic purposes followed by CE-CT scans of selected body regions. PET/CT was started approximately 90 minutes following IV injection of 10-15 mCi of F-18 FDG on a GE Discovery PET/CT system. Oral contrast was given before F-18 FDG injection. The CE-CT was performed according to departmental protocol. RESULTS: Out of a total of 257 lesions, 210 were concordant between PET/CT and CE-CT. There were 47 discordant lesions, which were verified by either biopsy (35) or follow-up (12 PET positive CE-CT negative lesions). PET/CT correctly identified 25 true positive (TP). CE-CT identified 2 TP lesions missed by PET/CT which were false negatives (FNs): one liver metastasis with necrosis, which was nonavid to FDG uptake because of necrosis and a second one missed on abdominal metastatic node, which did not change staging or treatment. PET/CT incorrectly identified 2 false positive lesions while CE-CT incorrectly identified 18 false positive. TP recurrence of the disease was found by PET/CT in 44% (15/34 pts), whereas 56% (19/34 pts) were free of disease. The CE-CT described progression of the disease in 1 true negative PET/CT study and no progression in 2 TP PET/CT studies. The sensitivity, specificity, accuracy, positive productive value, and negative productive value for PET/CT were 97.8%, 93.5%, 97.3%, 99.1%, 85% and for CE-CT were 87.6%, 42%, 82.1%, 91.6%, 31.7%. CONCLUSION: In this study, PET/CT played a more important role than CE-CT scans alone and provided an impact on the management of breast cancer patients.

Scintigraphic visualization of an epigastric sentinel node in recurrent breast cancer after lumpectomy and postoperative radiation therapy.

Sentinel node imaging and biopsy have become standard procedures for staging early breast cancer. Positive sentinel lymph node (SLN) biopsy necessitates the need for axillary lymph node dissection (ALND). Failure to visualize a sentinel lymph node in recurrent breast cancer after treatment by surgery, chemotherapy, and high-dose postoperative radiation therapy is almost the case in every patient. The reason for failure to visualize the sentinel node is the fibrosis that follows high-dose radiotherapy and blocks the lymphatics preventing spread of the tumor cells to the lymph nodes. Alternative pathways for the drainage of lymph from the breast are developed in these patients. We have previously reported on the alternative pathways of lymphatics to the contralateral axilla, supraclavicular area, and also reported on the development of intramammary lymph nodes. In this report, we are presenting another alternative pathway of lymphatics to the region of the epigastrium below the lower end of the sternum.

The distinctive role of positron emission tomography/computed tomography in breast carcinoma with brown adipose tissue 2-fluoro-2-deoxy-d-glucose uptake.

The diagnostic power of an integrated positron emission tomography/computed tomography (PET/CT) system for whole-body 2-fluoro-2-deoxy-d-glucose (FDG) imaging is clearly demonstrated in this case report. The precise anatomic localization of FDG uptake with CT in a PET/CT scan of a patient with known breast carcinoma helped identify a contralateral breast tumor with axillary lymph node metastasis despite the presence of extensive physiologic brown fat FDG uptake. Accordingly, the patient received appropriate surgical management and pathologic confirmation of the disease.