Abdominal manifestations of extraosseous myeloma: cross-sectional imaging spectrum. J Comput Assist Tomogr. 2012;36:207-212. [PMID: 22446361 DOI: 10.1097/rct.0b013e318245c261]

Central Nervous System Myeloma and Unusual Extramedullary Localizations: Real Life Practical Guidance

Central nervous system localization of multiple myeloma (CNS-MM) accounts for about 1% of all MM during disease course or even rarer at diagnosis. A difference in the origin, i.e., osteodural or primary dural vs leptomeningeal/intraparenchymal, seems to define two distinct types of intracranial myeloma, with different clinical behavior. CNS-MM may occur also as a presentation of MM. Treatment is still unsatisfactory and many treatments have been reported: chemotherapy, intrathecal therapy, and radiotherapy, with dismal prognosis. Other sites of myeloma localization could be also of interest and deserve description. Because of the rarity and aggressiveness of the disease clinicians are often doubtful on how to treat it since there is no general agreement. Moreover, recent drugs such as the anti CD38 monoclonal antibody, immunomodulatory drugs, and proteasome inhibitors have changed the treatment of patients with MM with a significant improvement in overall response and survival. The role of novel agents in CNS MM management and unusual presentations will be discussed as well as the potential role of other new immunomodulatory drugs and proteasome inhibitors that seem to cross the blood-brain barrier. The purpose of this review is to increase awareness of the clinical unusual presentation and neuroradiological findings, give practical diagnostic advice and treatment options algorithm.

FDG-PET/CT Variants and Pitfalls in Haematological Malignancies

Hematologic malignancies represent a vast group of hematopoietic and lymphoid cancers that typically involve the blood, the bone marrow, and the lymphatic organs. Due to extensive research and well defined and standardized response criteria, the role of [¹⁸F]FDG-PET/CT is well defined in these malignancies. Never the less, the reliability of visual and quantitative interpretation of PET/CT may be impaired by several factors including inconsistent scanning protocols and image reconstruction methods. Furthermore, the uptake of [¹⁸F]FDG not only reflects tissue glucose consumption by malignant lesions, but also in other situations such as in inflammatory lesions, local and systemic infections, benign tumors, reactive thymic hyperplasia, histiocytic infiltration, among others; or following granulocyte colony stimulating factors therapy, radiation therapy, chemotherapy or surgical interventions, all of which are a potential source of false-positive or negative interpretations. Therefore it is of paramount importance for the Nuclear Medicine Physician to be familiar with, not only the normal distribution of [¹⁸F]FDG in the body, but also with the most frequent findings that may hamper a correct interpretation of the scan, which could ultimately alter the patients management. In this review, we describe these myriad of situations so the interpreting physician can be familiar with them, providing tools for their correct identification and interpretation when possible.

Extraosseous multiple myeloma: imaging spectrum in the abdomen and pelvis

Multiple myeloma represents a subset of plasma cell dyscrasias characterized by the proliferation of plasma cells typically in the bone marrow, representing approximately 1% of all cancers and 15% of hematologic malignancies. Often multiple myeloma is limited to the skeletal system; however, a small percentage (<5%) of patients will develop extraosseous manifestations. We review the current WHO classification of plasma cell dyscrasias and use multimodality imaging including US, CT, MRI, and PET-CT to illustrate the spectrum of extraosseous multiple myeloma in the abdomen and pelvis. Because extraosseous multiple myeloma is associated with a poorer prognosis and decreased survival, it is important for the radiologist to become familiar with a variety of extraosseous manifestations in the abdomen and pelvis, especially in a patient with a known diagnosis of multiple myeloma and the development of an abdominal or pelvic mass.

Imaging features of immune-mediated genitourinary disease

PURPOSE

Imaging features of immune-mediated genitourinary diseases often overlap, and the same disease may manifest in different ways, so understanding imaging findings in the context of the patient's entire clinical picture is important in providing the correct diagnosis.

METHODS

In this article, diseases mediated by the immune system which affect the genitourinary system are reviewed. Examples of immune-mediated genitourinary disease including IgG4-related disease, post-transplant lymphoproliferative disorder, immunodeficiency-associated lymphoproliferative disorder due to immunosuppressive and immunomodulatory medications, lymphoma, leukemia, myeloma, amyloidosis, and histiocytosis.

RESULTS

Clinical and imaging features will be presented which may help narrow the differential diagnosis for each disease.

CONCLUSION

Recognition of immune-related genitourinary disease is important for appropriate medical management as they may mimic other diseases both by imaging and clinical presentation.

MRI of common and uncommon pathologies involving the periportal space: a pictorial essay

Imaging detection and differential diagnoses of pathology involving the periportal space can be challenging. MRI is a useful technique for assessment of the periportal space since it readily distinguishes normal and abnormal vascular and biliary anatomy, and the excellent soft tissue discrimination allows for detection of subtle lesions. This pictorial essay describes the anatomy of the periportal space and illustrates the MRI appearance of a variety of pathologies that can affect this region.

Hematologic malignancies of the liver: spectrum of disease

The incidence of hematologic malignancies and their extranodal manifestations is continuously increasing. Previously unsuspected hepatic involvement in hematologic malignancies such as Hodgkin disease and non-Hodgkin lymphoma, posttransplant lymphoproliferative disorder, myeloid sarcoma (chloroma), multiple myeloma, Castleman disease, and lymphohistiocytosis may be seen by radiologists. Although the imaging features of more common hepatic diseases such as hepatocellular carcinoma, metastases, and infection may overlap with those of hepatic hematologic malignancies, combining the imaging features with clinical manifestations and laboratory findings can facilitate correct diagnosis. Clinical features that suggest a hematologic neoplasm as the cause of liver lesions include a young patient (<40 years of age), no known history of cancer, abnormal bone marrow biopsy results, fever of unknown origin, and night sweats. Imaging features that suggest hematologic malignancy include hepatosplenomegaly or splenic lesions, vascular encasement by a tumor without occlusion or thrombosis, an infiltrating mass at the hepatic hilum with no biliary obstruction, and widespread adenopathy above and below the diaphragm. Familiarity with the imaging features of hepatic hematologic malignancies permits correct provisional diagnosis and may influence therapeutic management. For example, when biopsy is performed, core biopsy may be needed in addition to fine-needle aspiration so that the tissue architecture of the neoplasm can be discerned. The predominant treatment of hematologic malignancies is chemotherapy or radiation therapy rather than surgery. Online supplemental material is available for this article.

Imaging features of haematological malignancies of kidneys

Haematological malignancies are relatively uncommon neoplasms of kidneys. Nevertheless, the incidence of these neoplasms is increasing, partly due to more widespread use of computed tomography and magnetic resonance imaging. This article discusses the clinical and imaging features of renal lymphoma, leukaemia, extra-osseous multiple myeloma, and post-transplant lymphoproliferative disorder. Although there is overlap of imaging features with other more common malignancies, such as transitional and renal cell cancers, the combination of imaging findings and the appropriate clinical picture should allow the radiologist to raise a provisional diagnosis of a haematological neoplasm. This has management implications including the preference for image-guided core biopsies and a shift towards medical rather than surgical therapy.

Hematologic malignancies of the pancreas

Hematologic malignancies are relatively uncommon neoplasms of abdominal soft tissue. This article discusses the clinical and imaging features of pancreatic lymphoma, pancreatic extraosseous multiple myeloma, granulocytic sarcoma (chloroma), posttransplant lymphoproliferative disorder, and Castleman disease. The combination of imaging findings and the appropriate clinical presentation should allow the radiologist to raise a provisional diagnosis of hematologic malignancy.

Nonneoplastic, benign, and malignant splenic diseases: cross-sectional imaging findings and rare disease entities

OBJECTIVE

Splenic lesions are commonly encountered and are often incidental in nature. Benign splenic vascular neoplasms include hemangioma, hamartoma, lymphangioma, extra-medullary hematopoiesis (EMH), and sclerosing angiomatoid nodular transformation (SANT). Uncommonly encountered entities of the spleen include focal EMH, focal myeloma, angiomyolipoma, and SANT. Primary splenic angiosarcoma is the most common malignant nonhematolymphoid malignancy of the spleen. Lymphoma, myeloma, and metastases are the other malignant entities involving the spleen. The clinical presentation, key imaging findings, and associations of benign, neoplastic, and malignant diseases that can involve the spleen will be discussed.

CONCLUSION

Radiologists can use multimodality imaging to diagnose entities involving the spleen by recognizing key imaging features and considering patient characteristics. However, biopsy may be warranted for definitive diagnosis when imaging findings are nonspecific.

Imaging of multiple myeloma: Current concepts

Medical imaging is of crucial importance for diagnosis and initial staging as well as for differentiation of multiple myeloma (MM) from other monoclonal plasma cell diseases. Conventional radiography represents the reference standard for diagnosis of MM due to its wide availability and low costs despite its known limitations such as low sensitivity, limited specificity and its inability to detect extraosseous lesions. Besides conventional radiography, newer cross-sectional imaging modalities such as whole-body low-dose computed tomography (CT), whole-body magnetic resonance imaging (MRI) and ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT are available for the diagnosis of osseous and extraosseous manifestations of MM. Whole-body low-dose CT is used increasingly, replacing conventional radiography at selected centers, due to its higher sensitivity for the detection of osseous lesions and its ability to diagnose extraosseous lesions. The highest sensitivity for both detection of bone marrow disease and extraosseous lesions can be achieved with whole-body MRI and ¹⁸F-FDG PET/CT. According to current evidence, MRI is the most sensitive method for initial staging while ¹⁸F-FDG PET/CT allows monitoring of treatment of MM. There is an evolving role for assessment of treatment response using newer MR imaging techniques. Future studies are needed to further define the exact role of the different imaging modalities for individual risk stratification and therapy monitoring.

Expression of cancer-testis antigen in multiple myeloma

Recently, the immunotherapy has been highlighted among cancer treatments. Cancer-testis antigen (CTA) has been studied in a variety of solid tumors because of its specific expression in tumors, and testis, ovary and placenta tissues, but not in other normal tissues. In order to provide a new approach for multiple myeloma (MM) immunotherapy, we examined the CTA expression in MM cell lines, and primary myeloma cells in patients with MM. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to detect the mRNA expression of MAGE-C1/CT7, SSX1, SSX2 and SSX4 in MM cell lines of RPMI-8226 and U266, and bone marrow (BM) cells of 25 MM patients and 18 healthy volunteers. The results showed that the 4 CTAs were expressed in RPMI-8226 and U266 cell lines. The positive expression rate of MAGE-C1/CT7, SSX1, SSX2 and SSX4 in the BM cells of 25 MM patients was 28% (7/25), 80% (20/25), 40% (10/25) and 68% (17/25), respectively. In contrast, the expression of any member of the CTAs was not detected in BM cells of 18 healthy volunteers. The expression of two or more CTAs was detected in 80% (20/25) MM patients, and that of at least one CTA in 88% (22/25). The mRNA expression levels of SSX1 and SSX4 were significantly higher in patients with MM at stage III than in those at stage I and II (P<0.05). No statistically significant differences were observed in the mRNA expression levels of MAGE-C1/CT7 and SSX2 in further stratified analyses by age, gender, MM types and percentage of MM cells in BM (P>0.05). In conclusion, our present study showed that MAGE-C1/CT7, SSX1, SSX2 and SSX4 were co-expressed in MM cell lines and the primary myeloma cells in MM patients, but not expressed in BM cells of healthy subjects. The mRNA levels of SSX1 and SSX4 are associated with MM clinical stage. This work may provide a new insight into MM immunotherapy in the future.

MAGE-C1/CT7 and MAGE-C2/CT10 are frequently expressed in multiple myeloma and can be explored in combined immunotherapy for this malignancy

The exact function of MAGE-C1/CT7 and MAGE-C2/CT10 is not yet understood in multiple myeloma (MM). However, the homologs MAGE-C1/CT7 and MAGE-C2/CT10 genes encode highly immunogeneic cancer/testis antigens (CTAs) and can be potential targets for T cell-based immunotherapy. MAGE-C1/CT7 and MAGE-C2/CT10 mRNA expression were investigated in MM patients, solitary plasmacytomas, monoclonal gammopathies of undetermined significance (MGUS) and bone marrow (BM) aspirates from healthy donors by RT-PCR. MAGE-C1/CT7 and MAGE-C1/CT10 were expressed in 67 and 59 % of the 46 MM analyzed patients. At least one of the genes was expressed in 76 % of MM cases. Solitary plasmacytoma also showed MAGE-C1/CT7 and MAGE-C2/CT10 expression. MAGE-C1/CT7 and MAGE-C2/CT10 were not expressed in normal BM samples, showing restricted expression of these CTA genes in MM, solitary plasmacytoma and MGUS. In the present study, we found high expression of the homologs MAGE-C1/CT7 and MAGE-C2/CT10 in monoclonal gammopathies and speculate whether these genes might represent a valuable therapeutic option for myeloma, in particular for combined immunotherapy.