Skip to main content

Claw sign of brachial plexopathy on 18F-FDG PET/CT in neurolymphomatosis following successful treatment of lymphoma

Abstract

Neurolymphomatosis is a rare neurological manifestation associated with non-Hodgkin’s lymphoma. Here we present a case of brachial plexus neurolymphomatosis in a patient with relapsed non-Hodgkin’s lymphoma exquisitely demonstrated on 18F-FDG PET/CT. It highlights the characteristic imaging features and importance of multimodality imaging in diagnosing neurolymphomatosis.

Neurolymphomatosis is a rare neurological complication of Non-Hodgkin’s lymphoma (NHL), often clinically presenting as a radiculopathy (Grisariu et al. 2010; Baehring et al. 2003).

We present the imaging findings in a 60-year-old Caucasian man with stage III NHL who underwent routine surveillance with PET using fluorodeoxyglucose (18F-FDG) integrated with computed tomography (18FDG-PET/CT) following initial complete (Deauville 1) metabolic response to standard chemotherapy regimen.

18F-FDG-PET/CT demonstrated claw-shaped asymmetrical right sided, multi-segmental intense linear 18F-FDG uptake, in the distribution of C5 to T1 nerve roots with extension of abnormal uptake along the trunks and cords of the right brachial plexus, most elegantly displayed on the maximum intensity projection (MIP) image (Fig. 1, thick arrow) and confirmed on the multiplanar fused images (Figs. 2, 3). No structural abnormality was evident on the CT component of the study. New nodal disease was illustrated in the upper abdomen (Fig. 1, curved arrow) without central nervous system (CNS) involvement. At the time of 18F-FDG PET/CT imaging, the patient had right upper limb weakness and neuropathic pain which had been ongoing for 1 month, although this vital clinical information had not been disclosed on the referral letter. Of note, an MRI with dedicated brachial plexus protocol, performed 3 weeks earlier, had failed to identify any abnormality. In the context of previously treated NHL and scintigraphic evidence of right-sided radiculopathy on 18F-FDG PET/CT, a diagnosis of neurolymphomatosis was made. This diagnosis was subsequently endorsed following discussion with the referring clinician and disclosure of the relevant clinical information.

Fig. 1
figure 1

MIP image from whole-body 18F-FDG-PET/CT demonstrates claw-shaped asymmetrical right sided, multi-segmental intense linear 18F-FDG uptake, in the distribution of C5 to T1 nerve roots of the brachial plexus (straight arrow) and nodal recurrence below the diaphragm (curved arrow)

Fig. 2
figure 2

Axial PET, fused and CT images (B, C and D) at the level of exit foramina in lower neck. Note intense uptake by the nerve roots on the right from C5 to T1. Coronal PET, CT and fused images (E, F and G) and Sagittal PET, CT and fused images (H, I and J) confirm the uptake in the distribution of the brachial plexus

Fig. 3
figure 3

Axial PET, fused and CT images (B, C and D) at the level of the right clavicle. Note intense uptake by the trunks and cords. Coronal PET, CT and fused images (E, F and G) and Sagittal PET, CT and fused images (H, I and J) confirm the uptake in the distribution of the brachial plexus

MRI and 18F-FDG PET/CT demonstrate the abnormality in 80 and 88% of cases, respectively (Grisariu et al. 2010). An infiltrative pattern of 18F-FDG PET/CT uptake, involving a neural plexus or along a peripheral nerve, is the typical finding at 18F-FDG PET/CT (Strobel et al. 1244; Ozturk et al. 2006; Zhou et al. 2014). Accompanying CT images will often be normal; however, occasionally nodular thickening of the affected nerve segment can be identified (Strobel et al. 1244).

18F-FDG PET/CT is an essential part of staging and monitoring treatment response in patients with NHL (Johnson et al. 2015). It is exquisitely sensitive to the presence of high-grade lymphoma due to the intense inherent metabolic activity associated with such tumours and is particularly useful for identifying and staging extra-nodal disease (Zhou et al. 2014; Johnson et al. 2015). Neurolymphomatosis is at its essence, extra-nodal lymphomatous infiltration of neural tissue, which in conjunction with the typically small patchy nature of the lesions (Zhou et al. 2014) could potentially explain the diagnostic advantage of 18F-FDG PET/CT over MRI. Also relevant is the timeline between the two studies in our case, with MRI performed 3 weeks earlier, arguably too soon to identify the abnormalities seen on the subsequent 18F-FDG PET/CT.

Neurolymphomatosis can be treated by a combination of systemic chemotherapy, intrathecal chemotherapy and local radiotherapy (Grisariu et al. 2010). Treatment response is highly variable with a poor median survival following diagnosis of just 10 months (Grisariu et al. 2010; Matsuoka-Kamiya et al. 2014).

MRI is the modality of choice during the initial work-up in patients with peripheral nerve symptoms such as radiculopathy. Novel MR techniques such as whole body diffusion weighted imaging might be helpful to extract the functional information needed to make the correct diagnosis and avoid false negative results (Tanaka et al. 2013). Our case underscores the importance of multi-modality/metabolic imaging in the context of known NHL and persistent symptoms, where there is a strong clinical suspicion of neurolymphomatosis. It is imperative to communicate essential clinical information with the nuclear medicine department to avoid diagnostic ambiguity or mis-interpretation.

Conclusion

This case highlights the importance of multimodality imaging where there is strong clinical suspicion of neurolymphomatosis. It also demonstrates the characteristic imaging features on 18F-FDG PET/CT of brachial plexus neurolymphomatosis. Providing the diagnosticians with contemporary and relevant clinical information is paramount to avoid diagnostic ambiguity and erroneously assigning the scintigraphic findings to a wrong pathological process. MRI remains the diagnostic modality of choice; however, a negative study should not result in loss of confidence of the reporter in interpretation of the abnormalities seen on the 18F-FDG PET/CT.

Availability of data and materials

Not applicable.

Abbreviations

NHL:

Non-Hodgkin’s lymphoma

MIP:

Maximum intensity projection

CNS:

Central nervous system

References

  • Baehring JM, Damek D, Martin EC, Betensky RA, Hochberg FH (2003) Neurolymphomatosis. Neuro Oncol 5(2):104–115

    Article  Google Scholar 

  • Grisariu S, Avni B, Batchelor TT, van den Bent MJ, Bokstein F, Schiff D, Kuittinen O, Chamberlain MC, Roth P, Nemets A, Shalom E, Ben-Yehuda D, Siegal T, International Primary CNS Lymphoma Collaborative Group (2010) Neurolymphomatosis: an international primary CNS Lymphoma Collaborative Group report. Blood 115(24):5005–5011

    CAS  Article  Google Scholar 

  • Johnson SA, Kumar A, Matasar MJ, Schoder H, Rademaker J (2015) Imaging for staging and response assessment in lymphoma. Radiology 276:2

    Article  Google Scholar 

  • Matsuoka-Kamiya C, Shroff S, Gildersleeve K, Hormozdi B, Manning JT, Woodman KH (2014) Neurolymphomatosis: a case series of clinical manifestations, treatments and outcomes. J Neurol Sci 343(1–2):144–148

    Article  Google Scholar 

  • Ozturk E, Arpaci F, Kocaoglu M, Arslan N, Bulakbasi N, Ozguven M (2006) Detection of widespread neurolymphomatosis with 18F-FDG PET. Eur J Nucl Med Mol Imaging 33:975–976

    Article  Google Scholar 

  • Strobel K, Pestalozzi B, Ciernik I, Schaefer NG, Yousefi Koma A, Hany TF (2006) Changing PET/CT manifestation of neurolymphomatosis. Eur J Nucl Med Mol Imaging 33:1244

    Article  Google Scholar 

  • Tanaka H, Yoshino K, Sakaida E, Hashimoto S, Takeda Y, Kawajiri C, Takagi T, Nakaseko C (2013) Secondary neurolymphomatosis detected by whole-body diffusion-weighted magnetic resonance imaging: a case report. J Clin Exp Hematop 53(3):221–226

    Article  Google Scholar 

  • Zhou WI, Wu HB, Weng CS, Han YJ, Wang M, Huang S, Wang QS (2014) Usefulness of 18F-FDG PET/CT in the detection of neurolymphomatosis. Nucl Med Commun 35(11):1107–1111

    CAS  Article  Google Scholar 

Download references

Acknowledgements

Not applicable.

Funding

No funding was obtained for this case report.

Author information

Authors and Affiliations

Authors

Contributions

SD was involved in project conception, analysed and interpreted the images, was a major contributor to the manuscript writing and was involved in manuscript editing and finalisation. GL was involved in in project conception and read and approved final manuscript. AN conceived the project, was involved in project conception, analysed and interpreted the images, was a major contributor to the manuscript writing and was involved in manuscript editing and finalisation. All authors read and approved the final manuscript.

Corresponding author

Correspondence to Afshin Nasoodi.

Ethics declarations

Ethics approval and consent to participate

Not applicable.

Consent for publication

This work was considered exempt from informed consent requirements in line with departmental agreements.

Competing interests

The authors declare that they have no competing interests.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Doran, S., Lambe, G. & Nasoodi, A. Claw sign of brachial plexopathy on 18F-FDG PET/CT in neurolymphomatosis following successful treatment of lymphoma. European J Hybrid Imaging 6, 11 (2022). https://doi.org/10.1186/s41824-022-00132-7

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/s41824-022-00132-7

Keywords

  • PET/CT
  • Oncology imaging
  • Neurolymphomatosis
  • Non-Hodgkins lymphoma
  • Brachial plexus