Imaging of lymphoma of the musculoskeletal system

Musculoskeletal manifestations of lymphoma: a case series

Lymphomas are a heterogenous group of cancers of the lymphatic system in which disease primarily arises in lymph nodes. Extranodal disease is common; however, musculoskeletal involvement is rare. Imaging plays an important role in the diagnosis and staging of all lymphomas. In this case series, we present examples of musculoskeletal involvement of lymphoma encountered at our institution. We outline the clinical presentation and imaging findings of each and use these cases to review the features that can help to differentiate lymphoma from other musculoskeletal lesions.

Imaging features of skeletal muscle lymphoma: a case report and literature review

BACKGROUND

Diffuse large B cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma (NHL), occurring predominantly in older people. Skeletal muscle lymphoma is a rare form of DLBCL, most frequently affecting the thigh, upper extremities, calf, and pelvis.

CASE PRESENTATION

We report a case of skeletal muscle DLBCL that was diagnosed using ultrasound (US)-guided biopsy. A 70-year-old man presented with progressive swelling and pain in the left lower extremity and an elevated erythrocyte sedimentation rate (ESR) and serum C-reactive protein (CRP), ferritin, and CA125 levels. US, magnetic resonance imaging (MRI), and computed tomography (CT) showed diffuse lesions in several muscles of the left lower extremity. Positron emission tomography/CT (PET/CT) showed FDG-uptake in the affected muscles. The patient was treated with chemotherapy and achieved a good response. A systematic review of the literature published between 1992 and 2019 was conducted to investigate the role of imaging, including imaging-guided biopsy, in the diagnosis of skeletal muscle lymphoma.

CONCLUSIONS

Skeletal muscle lymphoma is rare. US and MRI features include enlargement of muscular structures, with preservation of the architecture of the tissue and surrounding anatomical structures. Definitive diagnosis relies on histological and immunohistological analysis of a sample obtained through imaging-guided biopsy.

ABC-type diffuse large B-cell lymphoma presenting as rotator cuff tendinopathy: A diagnostic dilemma and review of the literature

Diffuse large B-cell lymphoma often presents with extranodal manifestations involving the musculoskeletal system. Shoulder pain is particularly worrisome for malignancy. Individuals presenting with refractory upper extremity complaints should undergo a prompt and thorough evaluation for cancer, as a delay in diagnosis can result in an unfavorable outcome.

Among the fibers: A multimodality imaging review of intramuscular mass lesions

The common presentations of patient complaints regarding the musculoskeletal system, such as pain, swelling, and restriction of movement, lead to the imaging discovery of various lesions often located in, or arising from, skeletal muscle in the region of interest. Knowledge of the patients' clinical history, laboratory parameters, and various imaging characteristics of the implicated lesions would assist the radiologist in coming to a timely, reasonably accurate conclusion about the etiology of the patient's complaints, the severity of disease, and in directing patient therapy.

[Imaging characteristics of malignant and benign lesions of skeletal muscle]

There are many different tumors and tumor-like lesions with variable biological behavior that may affect the skeletal musculature. The aim of this study was to review the different intramuscular lesions and to provide a classification based on their radiological patterns. Intramuscular lesions can present as solid, liquid, semiliquid or fat equivalent manifestations and also as diffuse muscle enlargement and muscle calcification. Additionally, lesions with mixed patterns of the aforementioned alterations can also occur. Benign and malignant muscle lesions can often manifest with identical radiological patterns, which is why a certain differentiation is often difficult. A systematic radiological description and when possible assignment with respect to etiology and dignity depending on the patient history is necessary in order to recommend a subsequent histological confirmation or to avoid unnecessary confirmation.

The great mimicker at thoracolumbar spine: Non-Hodgkin's lymphoma

•

Non-Hodgkin’s lymphoma’s vertebral involvement is quite common.

•

Diagnosis of the non-Hodgkin’s lymphomas that are localized in thoracolumbar spine often is missed or is delayed.

•

It was purposed to report two cases with non-Hodgkin’s lymphoma in thoracolumbar spine with different presentation.

Purpose

To report two cases with Non-Hodgkin’s Lymphoma (NHL) in thoracolumbar spine with very different presentation.

Methods

Case 1; An 84-year-old female patient was admitted to our emergency clinic with paraparesis in both lower extremities. Magnetic resonance imaging (MRI) revealed an epidural mass at the level of the T12 vertebrae. She was operated immediately with wide laminectomy and posterior instrumentation because of the paraparesis of both lower extremities. Case 2; An 70-year-old female patient was admitted to our clinic with thoracolumbar back pain. There was a T12 vertebra compression fracture view in the X-ray imaging. MRI revealed multiple infiltrations in medullar canale at thoracolumbar spine with lytic lesion. She underwent eight cycles of chemotherapy.

Results

Multiple bone involvement was detected in both cases in PET-CT (Positron emission tomography–computed tomography) scans. Additionally it was found that there were nodal involvements accompanying these involvements in case 1. Because radiological examinations were not spesific enough to diagnose, it was necessary to perform a biopsy. The histopathological diagnosis of these patients revealed diffuse large B cell non-Hodgkin’s lymphoma.

Conclusions

Diagnosis of the non-Hodgkin’s lymphomas that are localized in thoracolumbar spine is often missed or delayed due to lack of specific findings and presence similarities to other diseases. Diagnosis is made by histopathologic examination. Although the main treatment is chemotherapy for these patients, surgery is necessary for patients with neurological deficite.

[Primary intramuscular non-Hodgkin's lymphoma in young subjects: about a case and review of the literature]

Primary extra-ganglionic non-Hodgkin's lymphoma (NHL) is rare and its primary intramuscular location is exceptional, as it account for less than 0.5% of all patients. It generally affects men, with an average age of 70 years. Standard treatment is based on surgical excision combined with chemotherapy and radiation therapy. We report the case of a 31-year old patient presenting with muscular pseudotumoral syndrome at the level of the right leg. Histological examination showed intramuscular large B-cell non-Hodgkin's lymphoma. The patient underwent exclusive chemotherapy with complete remission.

Imaging for Staging and Response Assessment in Lymphoma

Lymphoma comprises a heterogeneous group of diseases; remarkable advances have been made in diagnosis and treatment. Diagnostic imaging provides important information for staging and response assessment in patients with lymphoma. Over the years, staging systems have been refined, and dedicated criteria have been developed for evaluating response to therapy with both computed tomography (CT) and fluorine-18 fluorodeoxyglucose positron emission tomography (PET)/CT. The most recent system proposed for staging and response assessment, known as the Lugano classification, applies to both Hodgkin and non-Hodgkin lymphoma. The use of standardized criteria for staging and response assessment is important for making accurate treatment decisions and for determining the direction of further research. This review provides an overview of the updated CT and PET response criteria to familiarize the radiologist with the most important and clinically relevant aspects of lymphoma imaging. It also provides a short clinical update on lymphoma and the associated spectrum of imaging findings.

Primary skeletal muscle diffuse large B cell lymphoma: A case report and review of the literature

The occurrence of primary extranodal non-Hodgkin's lymphoma (NHL) of soft tissue is rare, particularly in skeletal muscle. The present study describes a case of diffuse large B cell lymphoma of the right lower extremity and provides a detailed review of the literature associated with this disorder, with the aim of improving the future diagnosis and therapy of extranodal NHL. The present case report was of a 76-year-old woman who presented with a right thigh and calf mass. In view of the tumor's location and the patient's age, soft tissue tumors were considered to be soft tissue sarcoma. Imaging scans were performed to determine the location and size of the tumor, followed by a biopsy of the muscle. Histopathological examination then yielded a diagnosis of diffuse large B cell lymphoma. The patient then underwent 4 cycles of chemotherapy. There was evident relief of pain and swelling in the right extremity; however, positron emission tomography/computed tomography (PET/CT) determined insufficient treatment efficacy. Chemotherapy was adjusted for 2 cycles; however, the patient suffered an aggravation of edema, so a different chemotherapy regimen of bleomycin, cytarabine, vincristine, cyclosphamide and dexamethasone (BCOAD) was performed for a further 2 cycles. The edema was alleviated and magnetic resonance imaging revealed shrinkage of the lower limb mass and the right thigh mass was undetectable. In conclusion, the present case report demonstrated that PET/CT may help determine the efficacy of chemotherapy treatment and that the BCOAD chemotherapy regimen may be more effective than standard treatments in certain cases.

Comparison of CE-FDG-PET/CT with CE-FDG-PET/MR in the evaluation of osseous metastases in breast cancer patients

BACKGROUND

Despite improvements in treatments, metastatic breast cancer remains difficult to cure. Bones constitute the most common site of first-time recurrence, occurring in 40-75% of cases. Therefore, evaluation for possible osseous metastases is crucial. Technetium 99 ((99)Tc) bone scintigraphy and fluorodexossyglucose (FDG) positron emission tomography (PET)-computed tomography (PET-CT) are the most commonly used techniques to assess osseous metastasis. PET magnetic resonance (PET-MR) imaging is an innovative technique still under investigation. We compared the capability of PET-MR to that of same-day PET-CT to assess osseous metastases in patients with breast cancer.

METHODS

One hundred and nine patients with breast cancer, who underwent same-day contrast enhanced (CE)-PET-CT and CE-PET-MR, were evaluated. CE-PET-CT and CE-PET-MR studies were interpreted by consensus by a radiologist and a nuclear medicine physician. Correlations with prior imaging and follow-up studies were used as the reference standard. Binomial confidence intervals and a χ(2) test were used for categorical data, and paired t-test was used for the SUVmax data; a non-informative prior Bayesian approach was used to estimate and compare the specificities.

RESULTS

Osseous metastases affected 25 out 109 patients. Metastases were demonstrated by CE-PET-CT in 22 out of 25 patients (88%±7%), and by CE-PET-MR in 25 out of 25 patients (100%). CE-PET-CT revealed 90 osseous metastases and CE-PET-MR revealed 141 osseous metastases (P<0.001). The estimated sensitivity of CE-PET-CT and CE-PET-MR were 0.8519 and 0.9630, respectively. The estimated specificity for CE-FDG-PET-MR was 0.9884. The specificity of CE-PET-CT cannot be determined from patient-level data, because CE-PET-CT yielded a false-positive lesion in a patient who also had other, true metastases.

CONCLUSIONS

CE-PET-MR detected a higher number of osseous metastases than did same-day CE-PET-CT, and was positive for 12% of the patients deemed osseous metastasis-negative on the basis of CE-PET-CT.

Malignant and benign lesions of the skeletal musculature

There are several tumors and tumorlike conditions with variable biological behavior that may involve the skeletal musculature. The aim of this work was to review different intramuscular lesions and to provide a classification of muscle lesions based on their radiological patterns as well as to provide as a pictorial essay the imaging characteristics of typical muscle lesions. Radiologically, intramuscular lesions can manifest as solid masses, liquid or semiliquid masses, fat-containing lesions, diffuse muscle enlargement, and muscle calcifications. Additionally, lesions with mixed patterns can also occur. It is noteworthy that different malignant or benign muscle lesions can manifest with identical radiological patterns.

Imaging of musculoskeletal lymphoma

Lymphoma of the musculoskeletal system involving the bone, muscle or skin is commonly due to secondary involvement from disseminated disease but can occasionally present as primary extranodal disease. Although radiological features are traditionally known to be non-specific, recognition of certain characteristics using summation of imaging modalities as well as knowledge of clinical features can help in making the diagnosis. Imaging also plays an integral role in treatment response assessments, especially via positron emission tomography/computed tomography functional imaging.

Clinical impact of PET/MR imaging in patients with cancer undergoing same-day PET/CT: initial experience in 134 patients--a hypothesis-generating exploratory study

PURPOSE

To compare the clinical impact of combined positron emission tomography (PET) and magnetic resonance (MR) imaging to that of combined PET and computed tomography (CT) performed on the same day in patients with cancer.

MATERIALS AND METHODS

This HIPAA-compliant retrospective study was approved by the institutional review board. Patients gave written informed consent for study enrollment, including the possibility to use their imaging and clinical data in future evaluations. A total of 134 patients with cancer with a non-central nervous system primary neoplasm underwent same-day fluorodeoxyglucose (FDG) PET/CT and FDG PET/MR imaging. PET/CT and PET/MR studies were independently interpreted by teams of radiologists and nuclear medicine physicians. Four readers, divided into two teams composed of one radiologist and one nuclear medicine physician each, read all 134 studies. The referring physician classified discordance between PET/CT and PET/MR observations either as findings affecting clinical management or as findings not affecting clinical management. Data were compared with the χ(2) test.

RESULTS

Findings affecting clinical management were noted for PET/CT studies but not for PET/MR studies in two (1.5%) of 134 patients and for PET/MR studies but not for PET/CT studies in 24 (17.9%) of 134 patients. The discrepancies between findings affecting clinical management detected with PET/MR imaging over those detected with PET/CT were significant (P < .001).

CONCLUSION

In these patients, PET/MR imaging alone contributed to clinical management more often than did PET/CT alone. PET/MR imaging provides information that affects the care of patients with cancer and is unavailable from PET/CT. Online supplemental material is available for this article.

Epiphyseal Ewing Sarcoma

Ewing sarcoma is the second most common pediatric malignant bone neoplasm after osteosarcoma. Ewing sarcoma comprises “small, round, blue-cell” tumors thought to arise from neural crest cells. The authors report the case of a 14-year-old boy that presented with a nonpainful circumscribed lesion. The radiographs showed a lytic lesion at the tibial epiphysis with a large soft tissue mass, best depicted in the magnetic resonance imaging scan that suggested an aggressive lesion. A needle biopsy of the lesion was performed. The diagnosis of Ewing sarcoma was made based on microscopic, immunohistochemical, polymerase chain reaction, and fluorescence in situ hybridization. This is the third case report about a primary epiphyseal Ewing sarcoma and the fist one with molecular confirmation.

Grading and characterization of soft tissue tumors on magnetic resonance imaging: the value of an expert second opinion report

Objective

To retrospectively compare the accuracy of the initial MRI (magnetic resonance imaging) report of referring radiologists and the second opinion report.

Material and methods

MRI of 155 patients presenting with a soft tissue tumor (STT) in a single large community center were referred for inclusion in the Belgian Soft Tissue Neoplasm Registry (BSTNR). The initial report and the second opinion report were made independently. Histopathology (gold standard) was obtained in 90 patients (group 1). In 65 patients, the diagnosis was made by the combination of clinical findings and/or follow-up (group 2). In group 1, the concordance in grading and tissue-specific (TS) diagnosis between the referring center (RC) and expert center (EC) was reviewed.

Results

In group 1, MR grading yields a sensitivity of 100% and a specificity of 89% in the EC. The sensitivity was 88% and the specificity 81% in the RC. The accuracy was significantly higher in the EC (92%) compared to the RC (83%) (p = 0.039). The TS diagnosis was correct in 50% versus 38.5% of malignant tumors and in 71.8% versus 51.6% of benign tumors in the EC and RC respectively.

Conclusion

A second opinion report increases the accuracy in the diagnosis of STT on MRI.

Main Messages

• A second opinion MRI report increases the overall accuracy in the diagnosis of soft tissue tumors.

• There is a good overall agreement in MR grading between the referring and expert institution.

• In the expert center, there were fewer false-negative and false-positive diagnoses.

• MRI performs better in the tissue-specific diagnosis of benign versus malignant STT.

Extranodal lymphoma from head to toe: part 2, the trunk and extremities

OBJECTIVE

Lymphoma can affect virtually every tissue in the body, producing a variety of imaging appearances. In this article, the extranodal manifestations of this disease in the trunk and extremities are illustrated and the imaging features that aid in the diagnosis are reviewed.

CONCLUSION

Knowledge of the imaging appearances of extranodal lymphoma can aid the differential diagnosis of mass lesions encountered in tissues throughout the body on different imaging modalities.

MRI features of skeletal muscle lymphoma

OBJECTIVE

The purpose of this study was to assess the MRI findings of skeletal muscle lymphoma.

MATERIALS AND METHODS

MR images of pathologically proven lymphoma of skeletal muscle in 20 patients were retrospectively reviewed for the presence or absence of individual imaging findings. Nine patients had primary muscle lymphoma, and 11 patients had muscle metastasis from systemic lymphoma.

RESULTS

The initial manifestation of skeletal muscle lymphoma was a muscle mass in 15 patients (75%) and abnormal muscle signal intensity in five patients (25%). Muscle enlargement was found in all cases. Long segmental involvement with orientation of the tumor along muscle fascicles was found in 15 patients (75%). Seventeen patients (85%) had traversing vessels within involved muscles. All of the tumors had equal to slightly increased signal intensity compared with normal muscle on T1-weighted images and intermediate signal intensity compared with fat on T2-weighted images. Among the 19 patients who underwent contrast-enhanced imaging, skeletal muscle lymphoma exhibited diffuse homogeneous enhancement in 13 patients (68%), predominantly peripheral thick bandlike enhancement in four patients (21%), and marginal septal enhancement in two patients (11%). Thick irregular enhancement of both deep and superficial fascia was found in 16 patients (84%), and one patient (5%) had deep enhancement only. Subcutaneous stranding was found in 16 patients (80%) and skin thickening in four patients (20%).

CONCLUSION

Skeletal muscle lymphoma has distinctive MRI features that help differentiate it from other soft-tissue tumors and tumorlike lesions.

Clinical utility of PET/CT in lymphoma

OBJECTIVE

The purpose of this review is to assist interpreting radiologists in becoming familiar with the role of PET/CT in baseline staging and therapeutic response assessment in the management of lymphoma, in becoming aware of imaging pitfalls, and in understanding the natural behavior of lymphoma and the therapeutic options.

CONCLUSION

Therapeutic strategies for the management of lymphoma are constantly being refined to improve long-term survival with the lowest risk of toxicity to the patient. PET/CT is accurate for baseline staging and yields important prognostic information for determining the most appropriate initial treatment. Used for evaluation of treatment response, PET/CT can depict residual viable malignant lesions with greater accuracy than can other imaging techniques. The findings thereby influence decisions about the need for additional or alternative treatment.