Waldenstroms Macroglobulinemia Patient Presenting with Rare 'lytic' Lesions and Hypercalcemia: A Diagnostic Dilemma

Bone Involvement as a Primary Rare Manifestation of Waldenstrom Macroglobulinemia: A Case Report and Prevalence in a Nationwide Population-Based Cohort Study

Bone involvement is a rare extranodal manifestation in patients with malignant lymphoproliferative diseases and has also been noted as a rare event in patients with Waldenstrom macroglobulinemia (WM). However, the actual prevalence has not been previously reported. We describe an unusual case of a patient with WM who presented with lower back pain and focal bone lesions at initial diagnosis. Magnetic resonance imaging (MRI) revealed multiple vertebral fractures. Positron emission tomography (PET) detected only nodal changes without pathological skeletal-related metabolic activity. Lymph node and bone marrow biopsies combined with an immunoglobulin M (IgM) M component revealed the diagnosis of WM. A next-generation sequencing (NGS) analysis using a targeted lymphoma panel of 59 recurrently mutated genes in lymphoid neoplasms showed mutations in the MYD88 and CD79B genes. After treatment with rituximab and bendamustine, the patient achieved a partial remission and pain relief. After 3 years of stable disease, a spontaneous subcapital fracture at the base of the femoral neck and new vertebral compression fractures occurred. Whole-body low-dose computed tomography (WB-LDCT) and bone density (dual energy X-ray absorptiometry (DEXA)) scan revealed marked osteopenia. After insertion of a hip prosthesis, examination of the removed hip showed infiltration of clonal lymphoplasmacytic cells. Our case confirms that one must be aware that bone involvement in patients with WM can occur as a rare manifestation. Interestingly, the MYD88/CD79B-mutated (MCD) genotype in diffuse large B-cell lymphoma is characterized by extranodal involvement and may also be involved in the pathogenesis of skeletal-related disease in the present case. As a follow-up to this unusual case, we have carried out an analysis based on the Danish Lymphoma Registry (LYFO) covering the entire national population in the period 2000 - 2020. The registry study included a cohort of 2,459 patients with WM and lymphoplasmacytic lymphoma. Our data revealed that primary bone involvement at diagnosis occurs in 1.75% of adults with WM. To the best of our knowledge, this is the first report of the prevalence of skeletal-related disease in a large nationwide cohort and defines bone involvement as an exceedingly rare event in WM.

Clinical Presentation and Gene Expression Profiling of Immunoglobulin M Multiple Myeloma Compared With Other Myeloma Subtypes and Waldenström Macroglobulinemia

PURPOSE

Multiple myeloma (MM) is a clonal bone marrow disease characterized by the neoplastic transformation of differentiated postgerminal B cells. It is a heterogeneous disease both at the genetic level and in terms of clinical outcome. Immunoglobulin M (IgM) MM is a rare subtype of myeloma. Similar to Waldenström macroglobulinemia (WM), patients with MM experience IgM monoclonal gammopathy; however, both diseases are distinct in terms of treatment and clinical behavior.

MATERIALS AND METHODS

To shed light on the presentation of IgM MM, its prognosis, and its gene expression profiling, we identified and characterized 21 patients with IgM MM from our database.

RESULTS

One of these patients presented with a rare IgM monoclonal gammopathy of undetermined significance that progressed to smoldering myeloma. The median survival of the 21 patients was 4.9 years, which was comparable to a matched group of patients with non-IgM MM with similar myeloma prognostic factors (age, gender, albumin, creatinine, anemia, lactate dehydrogenase, β₂-microglobulin, cytogenetics abnormalities), but much less than the median survival reported for patients with WM (9 years). We identified a cluster of genes that differ in their expression profile between MM and WM and found that the patients with IgM MM displayed a gene expression profile most similar to patients with non-IgM MM, confirming that IgM MM is a subtype of MM that should be differentiated from WM.

CONCLUSION

Because the prognosis of IgM MM and WM differ significantly, an accurate diagnosis is essential. Our gene expression model can assist with the differential diagnosis in controversial cases.

Controversies in Serotonin Syndrome Diagnosis and Management: A Review

Over the past few years, Serotonin Syndrome (SS) has become a significant clinical concern. Over the last decade, United States saw a surge in antidepressant use. SS characteristically presents as the triad of altered mental status, autonomic dysfunction and neuromuscular excitation. Symptoms vary from patient to patient with mild cases presenting with subacute symptoms and severe cases progressing rapidly to death. Due to the protean manifestations of the syndrome along with non-specific prodromal, SS can easily be misdiagnosed if not carefully assessed. In severe cases, SS can be mistaken as neuroleptic malignant syndrome while mild cases are mostly misattributed to other causes such as flu. SS is a clinical diagnosis and therefore, requires a thorough review of medications and physical examination. Given the protean nature of this toxicologic syndrome various criteria were defined which includes Sternbach's, Radomski and Hunter's criteria. Keeping in mind the wide symptoms of serotonin syndrome from being barely perceptible to lethal emphasis there is a need to treat the syndrome on urgent basis. Mainstay for treatment of serotonin syndrome is to discontinue the offending drug. Improvement is seen in most patients within 24 hours.

Topical vasodilator response in skeletonized internal mammary artery: Is there really a difference?

Aim of the Study:

Coronary artery bypass graft surgery is the gold standard for the treatment of multivessel and left main coronary artery disease. However, there is considerable debate that whether left internal mammary artery (IMA) should be taken as pedicled or skeletonized. This study was conducted to assess the difference in blood flow after the application of topical vasodilator in skeletonized and pedicled IMA.

Materials and Methods:

In this study, each patient underwent either skeletonized (n = 25) or pedicled IMA harvesting (n = 25). The type of graft on each individual patient was decided randomly. Intraoperative variables such as conduit length and blood flow were measured by the surgeon himself. The length of the grafted IMA was carefully determined in vivo, with the proximal and distal ends attached, from the first rib to IMA divergence. The IMA flow was measured on two separate occasions, before and after application of topical vasodilator. Known cases of subclavian artery stenosis and previous sternal radiation were excluded from the study.

Results:

The blood flow before the application of topical vasodilator was similar in both the groups (P = 0.227). However, the flow was significantly less in pedicled than skeletonized IMA after application of vasodilator (P < 0.0001). Similarly, the length of skeletonized graft was significantly higher than the length of pedicled graft (P < 0.0001).

Conclusion:

Our study signifies that skeletonization of IMA results in increased graft length and blood flow after the application of topical vasodilator. However, we recommend that long-term clinical trials should be conducted to fully determine long-term patency rates of skeletonized IMA.