Abdominal lymphoma staging: is MR imaging with T2-weighted turbo-spin-echo sequence a diagnostic alternative to contrast-enhanced spiral CT?

Imaging spectrum of mesenteric masses

Mesenteries are extensions of the visceral and parietal peritoneum consisting of fat, vessels, nerves, and lymphatics. Mesenteric masses have a wide differential diagnosis with neoplastic, infectious, or inflammatory etiologies and can either be solid or cystic. Imaging features are critical for the diagnosis. We review the epidemiology, imaging spectrum, and differentiating features and treatment of mesenteric masses.

PET-CT Imaging of Lymphoma

PET-CT is now the mainstay for imaging lymphoma patients. The complimentary nature of the metabolic and anatomic information provided by a PET-CT examination has become an essential component of patient management, complimenting clinical and laboratory criteria used in staging, restaging, and therapy monitoring. The nature of a particular lymphoma subtype and the patient’s clinical presentation will determine the extent PET-CT imaging is best employed in a particular patient’s management.

Renal involvement in lymphoma: prevalence and various patterns of involvement on abdominal CT

OBJECTIVE

The kidney is a frequent site of involvement in lymphoproliferative disorders. The aim of this study was to demonstrate the prevalence and spectrum of morphologic appearances of renal involvement in patients with lymphoma on helical computed tomographic (CT) scan.

METHODS

Three phases of post-contrast helical CT of the abdomen in 74 patients with lymphoma were reviewed for possible renal involvement: the cortico-medullary, nephrographic and delayed excretory phases. Tumor characteristics, patterns of distribution and enhancement features were evaluated.

RESULTS

Of the 74 patients with lymphoma, 11 had CT evidence of renal involvement--ten with non-Hodgkin's lymphoma and one with Hodgkin's lymphoma--representing 15% of all patients scanned for routine staging of histologically diagnosed lymphoma. Five types of renal involvement were observed: enlarged lobular non-enhancing kidneys (four patients); bilateral multiple renal masses (two patients); focal single non-enhancing mass (two patients); perirenal infiltrations from retroperitoneal extension (two patients); bilateral diffuse areas of non-enhancing hypo-densities (one patient).

CONCLUSION

Five distinct patterns of renal involvement with lymphoma were detected with helical CT. The most common appearance was enlarged lobular kidneys. CT with intravenous contrast enhancement is currently the approach of choice for both the evaluation of renal involvement as well as for accurate staging of lymphoma. Awareness of different patterns of renal involvement in lymphoma allows proper differentiation from other similar diseases.

CT diagnosis of 52 patients with lymphoma in abdominal lymph nodes

AIM: To assess CT manifestations and its diagnostic value for lymphoma in the abdominal lymph nodes (LALN).

METHODS: CT findings in 52 cases of LALN proved by surgery or biopsy, including Hodgkin’s disease (HD) in 16 cases and non-Hodgkin’s lymphoma (NHL) in 36 cases, were retrospectively analyzed.

RESULTS: (1) CT manifestations based on distribution of the lesions of LALN: Solitary mass type was found in 10 cases, including solitary, round, uniform-density, enlarged lymph nodes in 3 cases; and multiple, enlarged lymph nodes fusing into singular lobular mass in 7 cases. Thirty-four cases of multiple-nodular type showed multiple, round, enlarged lymph nodes with uniform density and clear margins. Vessels-embedded signs, including mesenteric vessels, renal vessels, abdominal aorta or inferior vena cava, were seen in 6 cases, and duodenum-embedded signs were seen in 2 cases. Eight cases of diffuse type showed characteristic “cobblestone signs”. (2) CT manifestations correlated with pathological type: CT manifestations of 12 cases of HD were different from those of 40 cases of NHL in distribution, size, quantity and fused lesion of enlarged lymph nodes. (3) Twenty-eight cases of 52 patients were accompanied with extra-nodal lymphoma in the abdomen, especially gastrointestinal lymphoma, which had characteristic CT findings. (4) In follow-up examinations, CT images showed uniform, heterogeneous or rim enhancement in 15 cases, and occasional calcifications accompanied with reduction of the lesion size and quantity in 12 cases, whereas the lesions disappeared in 3 cases after treatment.

CONCLUSION: CT images show many characteristic manifestations valuable for qualitative diagnosis of LALN, and it is also helpful for pathological classification of LALN and therapeutic evaluation in follow-up of patients.

CT and MR imaging in Hodgkin's disease - present and future

Initial staging of Hodgkin's disease is crucial to determine the location and extent of disease, and is the hallmark for the choice of treatment. At present, the established radiological technique for staging Hodgkin's disease is computed tomography (CT). Modern multidetector row CT scanners allow fast imaging from the scull base to the groins during a single breath hold with a spatial resolution of approximately 1 mm. Both, nodal and extranodal involvement of Hodgkin's disease can be diagnosed with CT. Magnetic resonance (MR) imaging is another useful cross-sectional imaging modality for staging Hodgkin's disease. The development of fast MR imaging techniques has considerably reduced imaging time without compromising the quality of MR images. As a consequence, MR imaging is now considered to be as diagnostic as CT for staging Hodgkin's disease. The excellent soft-tissue contrast and the lack of exposure to ionizing radiation are the main advantages of MR imaging. For the detection of extranodal Hodgkin's disease, MR imaging is superior to assess involvement of the brain, the spinal cord and bone marrow; while CT allows excellent evaluation of lung disease. Common major problems in staging Hodgkin's disease are still the detection of nodal involvement in normal sized lymph nodes and residual tumor masses after therapy. In the future, newly developed lymphotropic contrast agents for MR imaging might be helpful to answer these questions.

Staging of Malignant Lymphoma with Three-Station black-Blood Fast Short-Inversion Time Inversion Recovery (STIR)

PURPOSE

The purpose of this study was to assess the usefulness of three-station black-blood fast short-inversion time inversion recovery (STIR) imaging in detecting and staging malignant lymphoma.

METHODS

Seventeen patients with malignant lymphoma were examined with a 1.5T imager. The findings and stagings determined with three-station black-blood fast STIR imaging were compared with reference standards (e.g., computed tomography [CT] findings and clinical stagings).

RESULTS

Three-station black-blood fast STIR imaging provided a fat-suppressed T2-weighted imaging contrast with fewer flow artifacts and revealed nodal involvement as well as bone marrow and spleen involvement to an extent comparable with CT. Especially notable was the excellent specificity (94%) of this imaging technique. Regarding disease staging, significant agreement was observed between clinical staging (k=0.60) and staging as evaluated by three-station black-blood fast STIR, although the detection of lymphadenopathy in the thorax was relatively poor. The average time required for this imaging was approximately 30 min.

CONCLUSION

Three-station black-blood fast STIR MR imaging may be useful as a staging tool for malignant lymphoma because this imaging technique reveals lymphoma lesions, which determine the staging, without radiation exposure or the use of contrast agents.

Role of video-laparoscopy in the staging of intra-abdominal lymphomas and gastrointestinal cancer

There is good category II/III evidence that video-laparoscopic staging is valuable in certain gastrointestinal (gastric, esophageal, pancreatic, and hepatobiliary) and intra-abdominal lymphomas, but no category I evidence (based on prospective randomized trials). The evidence available is all retrospective, but of sufficient consistency to indicate that laparoscopic staging adds to the primary (imaging) staging and often alters the clinical stage of the disease and hence the management of the individual patient. The advent of laparoscopic contact ultrasound (LCU) scanning has improved the staging accuracy for pancreatic and hepatobiliary neoplasms. The laparoscopic approach also offers a means of surgical palliation in certain patient groups. However, there are a number of unresolved issues concerning the use of video-laparoscopy. The most important concerns whether staging laparoscopy should be performed immediately before scheduled surgery or as a separate intervention. The cost-efficacy of these two management options needs to be evaluated in prospective studies. In some centres, laparoscopic staging is being conducted by gastroenterologists and hepatologists. This raises issues of safety and ability to undertake certain procedures that may be necessary during the laparoscopic staging.