Unusual manifestation of intravascular large B-cell lymphoma: severe hypercalcemia with parathyroid hormone-related protein

Case Report: Intravascular Large B-Cell Lymphoma: A Clinicopathologic Study of Four Cases With Review of Additional 331 Cases in the Literature

Intravascular large B-cell lymphoma (IVLBCL) is a rare and highly malignant non-Hodgkin B-cell lymphoma with uncommon clinical presentation and poor prognosis. The diagnostic pitfall of IVLBCL is mainly due to the fact that subtle histological changes could be easily overlooked, in addition to its rare occurrence, non-specific and variable clinical presentations, and the absence of significant mass lesions. The purpose of this study is to further explore the clinicopathologic and molecular features of IVLBCL to ensure an accurate diagnosis of this entity. Here, we retrospectively present the data of the four new cases and the literature cases. The age ranged from 23 to 92, with a medium age of 67 and a male-to-female ratio of 1:1. The clinical manifestations are extremely variable, including fever, night sweats, weight loss, anemia, thrombocytopenia, unexplained hypoxemia, impaired consciousness, and skin lesions, as well as the extremely low levels of serum albumin, high levels of serum lactate dehydrogenase (LDH), soluble interleukin-2 receptor (sIL2R), and ferritin. Morphologically, 99.9% of cases showed a selective growth pattern with large, atypical lymphocytes within the lumen of small blood vessels. In addition, vast majority of cases were positive for CD20, CD79a, PAX5, MUM1, and BCL6, and a subset of cases expressed BCL2 and CD5, whereas CD3 and CD10 were typically negative. Ki-67 proliferative index ranged from 20% to 100%. To sum up, we have conducted comprehensive case reports, to the best of our knowledge, this is the largest reported cohort of IVLBCL cases. Comprehensive assessments and more IVLBCL cases are required for early diagnosis and prompt treatment.

Missed diagnosis of lymphoma presenting with humoral hypercalcemia of malignancy due to cessation of oncological workup after negative computed tomography scans

Malignancy is the most common cause of hypercalcemia among hospitalised patients and is frequently caused by elevations in parathyroid hormone-related peptide (PTHrP). The most common PTHrP-producing cancers are carcinomas of the head, neck and lung. Hypercalcemia can be the presenting sign of cancer and, in these cases, solid tumours are usually discovered on CT scan. In rare cases, lymphoma may also present with hypercalcemia. CT scan is less sensitive for lymphoma than for most solid tumours and the diagnosis may be missed. We present the case of a 69-year-old woman who presented with hypercalcemia in the setting of severe weight loss and elevated PTHrP. Oncological workup was stopped after unrevealing CT scans and an underlying lymphoma was missed. Our case emphasises the need for a comprehensive oncological workup for patients with unexplained hypercalcemia and elevated PTHrP, even when CT scans are unrevealing.

Imaging Features and Prognostic Value of FDG PET/CT in Patients with Intravascular Large B-Cell Lymphoma

Purpose

The clinical value of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) in intravascular large B-cell lymphoma (IVLBCL) is unknown. This study investigated the association between PET/CT features and prognosis in IVLBCL patients.

Patients and Methods

Subjects were 30 newly diagnosed Asian variant IVLBCL patients at a single institution. Baseline PET/CT was analyzed for the distribution and intensity of FDG lesions, and PET/CT pattern groups were compared for the outcome.

Results

Eight patients had hypermetabolic lymph node (LN) lesions (Nodal group). The remaining 22 patients with extranodal (EN) involvement were categorized into Deauville score 3–4 (EN/DS3-4; n = 14) and DS5 groups (EN/DS5; n = 8). First-line therapy resulted in a complete or partial response in 75.0%, 64.3%, and 100% of the respective groups. Treatment-related deaths occurred in one nodal group and three EN/DS3-4 group cases, but none among the EN/DS5 group. During 56 months of follow-up, disease progression or relapse occurred in five, four, and one case of respective groups. Cancer-related death occurred more frequently in the Nodal (n = 6) and EN/DS3-4 groups (n = 7) than the EN/DS5 group (n = 1; P = 0.041). Nodal and EN/DS3-4 groups had worse 5-year event-free survival (EFS; 25.0% and 49.0%, respectively, P = 0.010 and 0.076) and overall survival (OS; 33.3% and 48.2%, P = 0.010 and 0.068) compared to the EN/DS5 group (87.5% EFS and 87.5% OS).

Conclusion

In patients with Asian variant IVLBCL, the distribution and intensity of FDG uptake lesions on PET/CT can be useful for predicting treatment outcomes and survival.

Hypercalcemia in T-Cell/Histiocyte-Rich Large B-Cell Lymphoma: An Unusual Presentation of a Rare Disease and Literature Review

T-cell/histiocyte-rich large B-cell lymphoma (THRLBCL) is an extremely rare morphologic subtype of diffuse large B-cell lymphoma (DLBCL), accounting for only 1-3% of total cases. It is considered an aggressive lymphoma with a poor prognosis. Hypercalcemia has been described as an uncommon presenting symptom of patients with DLBCL in several case reports. Here, we report an unusual case of severe hypercalcemia in a patient who was ultimately diagnosed with T-cell/histiocyte-rich B-cell lymphoma. A 69-year-old male patient presented to our hospital with nausea, vomiting, weakness and unintentional weight loss. His initial blood tests showed a serum calcium level of 16.1 mg/dL and serum creatinine level of 3.25 mg/dL. He had high intact parathyroid hormone (PTH, 6.8 pg/mL), mildly elevated 25-hydroxyvitamin D and serum PTH-related peptide (PTHrP). To exclude malignancy, computed tomography (CT) scans of the chest, abdomen and pelvis were performed which were unremarkable. A bone marrow biopsy was performed to detect any hidden hematologic malignancy which showed large mononuclear cells with prominent nucleoli and occasional Reed-Sternberg cells, consistent with the diagnosis of THRLBCL. Subsequent positron emission tomography demonstrated diffuse fluorodeoxyglucose (FDG) uptake. This case reports a unique presentation of a rare subtype of non-Hodgkin's lymphoma. We highlight the importance of pursuing a thorough workup for causes of hypercalcemia as well as understanding the underlying mechanisms of severe hypercalcemia in malignancy.

Diagnosis of intravascular large B cell lymphoma: novel insights into clinicopathological features from 42 patients at a single institution over 20 years

This study aimed to clarify the comprehensive clinical, laboratory, pathological and imaging features of intravascular large B‐cell lymphoma (IVLBCL) using data on 42 IVLBCL patients diagnosed at our hospital over the past 20 years. The majority of patients were diagnosed via random skin biopsy (29/42, 69·0%) followed by bone marrow biopsy alone (8/42, 19·0%). Characteristic features included persistent fever (41/42, 97·6%), decreased performance status (≥2) (100%), hypoxaemia (32/40, 80·0%), impaired consciousness (19/42, 45·2%), hypoalbuminemia (42/42, 100%) and extreme elevation of lactate dehydrogenase and soluble interleukin 2 receptor levels. Brain magnetic resonance imaging showed abnormal findings in 32/37 patients (86·4%). Hyperintense lesion in the pons was a peculiar finding that was unrelated to the neurological deficits. Positron emission tomography‐computed tomography revealed a high incidence of bone marrow (26/34, 76·5%), spleen (19/34, 55·9%) and adrenal gland (9/34, 26·5%) involvement. Neurolymphomatosis was noted in 6 patients during the course of the disease. About 60% of IVLBCL patients in whom in vivo diagnosis was possible survived more than 5 years with combination chemotherapy. Our observations provide additional insight into the diagnosis of IVLBCL and indicate that early disease recognition via random skin biopsy combined with imaging, enables in vivo diagnosis of the disease and improved survival for many patients.

Primary Bone Marrow B-Cell Lymphoma Undetected by Multiple Imaging Modalities That Initially Presented with Hypercalcemia

Purpose

We report a rare case of severe hypercalcemia that was ultimately diagnosed as primary bone marrow diffuse large B-cell lymphoma (BCL).

Case Report

A 74-year-old male patient visited our hospital complaining of tenderness and swelling of the left knee caused by supracondylar fracture of the left distal femur. His initial blood tests showed a serum calcium level of 13.9 mg/dL, inorganic phosphorus of 4.34 mg/dL, and a serum creatinine level of 1.54 mg/dL. A serum assay of intact parathyroid hormone showed 5.24 pg/mL, and the patient's serum 25(OH)D level was 22.33 ng/mL. To exclude malignancy, we performed imaging studies, including abdomen or chest computed tomography and positron emission tomography-computed tomography; however, no suspicious lesion was found, although the serum PTH-related peptide level was elevated at 4.0 pmol/L. A bone marrow biopsy was performed to identify any hidden hematologic malignancy. As a result, the pathology of bone marrow confirmed the presence of atypical lymphocytes that stained positive for the CD20 marker, which is consistent with BCL involving the bone marrow.

Conclusion

This case highlights the importance of pursuing a thorough workup for rare underlying causes of hypercalcemia when parathyroid-related etiologies can be excluded.

[Clinical and pathological characteristics of intravascular lymphomas]

Intravascular B‑cell lymphomas (IVL) are rare neoplasms that can manifest at any age (mean age ~62-63 years). About half of the cases are associated with Epstein-Barr virus. The most common sites of manifestation are the brain, skin, and bone marrow. The diagnosis is difficult due to unspecific clinical presentation and laboratory changes. FACS (fluorescence-activated cell sorting) and clonality analysis from peripheral blood and radiological findings are often not diagnostic. The most sensitive and most specific diagnostic method is the histopathological and immunohistochemical evaluation of a tissue biopsy. Because of the rarity of this disease, little is known about therapy and prognosis, whereby therapy is mainly similar to non-IVL lymphomas. The prognosis is poor; median survival after diagnosis is approximately one year.