Diagnostic Panel of Markers CD45, CD20, CD3, CD138, and CD56 For10.5005/Jp-Journals-10015-1507 Oral Solitary Plasmacytoma of Bone Case Report

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Diagnostic Panel of Markers CD45, CD20, CD3, CD138, and CD56 for10.5005/jp-journals-10015-1507 Oral Solitary Plasmacytoma of Bone Case Report

Diagnostic Panel of Markers CD45, CD20, CD3, CD138, and CD56 for Oral Solitary Plasmacytoma of Bone 1Marin Abraham, 2Dominic Augustine, 3Parimala Sagar, 4Roopa S Rao, 5Kavitha Prasad, 6Samudrala V Sowmya 7Vanishri C Haragannavar, 8Shwetha Nambiar

ABSTRACT How to cite this article: Abraham M, Augustine D, Sagar P, Rao RS, Prasad K, Sowmya SV, Haragannavar VC, Nambiar S. Aim: The present case aims to emphasize on the role of immu- Diagnostic Panel of Markers CD45, CD20, CD3, CD138, and nophenotyping in plasmacytic malignancies. CD56 for Oral Solitary Plasmacytoma of Bone. World J Dent Introduction: Solitary plasmacytoma of bone (SPB) is a rare 2018;9(1):53-58. entity often encountered in vertebrae and less frequently in long bones. Its presence in jaws is extremely rare, accounting Source of support: Nil for 4.4% of cases only. About 5% of patients with plasma cell Conflict of interest: None dyscrasias present with SPB. Case report: An elderly male patient reported with a chief complaint of growth in the anterior region of the lower jaw INTRODUCTION since 3 months. The histopathological features following an incisional biopsy were suggestive of pyogenic granuloma. A plasmacytoma is a distinct, solitary mass of neoplastic Serological investigations revealed seropositivity for human monoclonal plasma cells present within the bone marrow immunodeficiency virus (HIV)-1 antibody with hypergamma- as SPB or EMP, which arises from plasma cells present globulinemia and hypoalbuminemia. Histopathology of exci- within the mucosal surface. Plasmacytomas are mono- sional biopsied tissue revealed a round cell malignancy with plasmacytic morphology. Further, to arrive at a specific final clonal and this can be assessed in tissue sections or by diagnosis, immunohistochemistry (IHC) was employed with a biochemical evaluation of the type of immunoglobulin panel of markers CD45, CD20, CD3, CD138, and CD56. This secreted by the neoplastic cells. Plasmacytomas are of panel enabled us to establish a final diagnosis of SPB with significance because they may ultimately give rise to clinicopathologic correlation. contemplative problems of MM. The SPB is a rare lesion Conclusion: The present case posed a diagnostic dilemma which emanates from bone marrow-based B cells, explic- as it presented with overlapping features of non-Hodgkin’s lymphoma (NHL), multiple myeloma (MM), extramedullary itly those that have undergone terminal differentiation plasmacytoma (EMP), and plasmablastic lymphoma (PBL). into plasma cells.1 The SPB exemplifies plasma cell dys- A thorough clinical, radiological, serological, and IHC panel crasias involving a single bone in the localized form due helped to diagnose the present case. The CD56 enabled differentiation between SPB and PBL. Thereby, this article to malignant plasma cell infiltrate. emphasizes on the need for a panel of IHC markers that permit It is essential to affirm the importance of HIV infec- definitive diagnosis of lymphopoietic malignancies. tion as a risk factor in cases of SPB, as it exhibits an Clinical significance: Timely diagnosis of malignant lesions aggressive and uncommon clinical presentation. The is an essential concern for effective management. Thus, we SPB documents a greater predilection in males and emphasize that the IHC is a valuable investigative tool in the is more evident in the 5 to 7 decade of life presenting diagnosis of round cell tumors with plasmacytoid morphology. more commonly in the axial skeleton, particularly at the Keywords: CD138, CD20, CD3, CD45, CD56, Enzyme- vertebrae. Korolkowa et al2 reported that 40% occur in linked immunosorbent assay, Immunohistochemistry, Multiple myeloma, Plasma cell dyscrasias, Solitary plasmacytoma. the nasal cavity and paranasal sinus, 20% in the nasopharynx, and 18% in the oropharynx. It rarely involves jaws, accounting for only 4.4% of cases in the mandible, 1,2,4,6-8Department of Oral Pathology and Microbiology, Faculty of most commonly in the bone marrow-rich areas of the Dental Sciences, M. S. Ramaiah University of Applied Sciences body, angle, and ramus regions.3 SPB most frequently Bengaluru, Karnataka, India occurs at the posterior mandible. It can progress into MM 3,5 Department of Oral and Maxillofacial Surgery, Faculty of in 50 to 60% of patients with a median overall survival Dental Sciences, M. S. Ramaiah University of Applied Sciences 4 Bengaluru, Karnataka, India time as 10 years. The SPB is an aggressive lesion that has the poten- Corresponding author: Marin Abraham, Department of Oral Pathology and Microbiology, Faculty of Dental Sciences, M. S. tial to transform into MM over a period of time. The Ramaiah University of Applied Sciences, Bengaluru, Karnataka expression of specific antigens by the neoplastic cells India, Phone: +919880323479, e-mail: marinabraham09@ plays an important role in the diagnosis and definite gmail.com management. World Journal of Dentistry, January-February 2018;9(1):53-58 53 Marin Abraham et al

CASE REPORT and hyperchromatic nuclei, numerous vesicular nuclei, prominent nucleoli, and bizarre morphology (Fig. 1E). A 78-year-old male patient reported to the dental out- With these observations, a diagnosis of malignant round patient department, Faculty of Dental Sciences, M. S. cell tumor was suggested. Areas of plasmacytoid cells Ramaiah University of Applied Sciences, Bengaluru, were also evident. The differential diagnosis included India, with a chief complaint of growth in the front region NHL, EMP, SPB, MM, and PBL. of the lower jaw for 3 months. It was sudden in onset Based on the radiographic features, MM was ruled out and increased gradually over 3 months. On inspection, a as multiple perforations of the mandible were found to solitary pedunculated erythematous lesion with irregular arise from a single lesion. The serum albumin globulin borders was present in relation to lower anterior teeth ratio was found to be normal, and test for Bence Jones region extending from 33 to 43 mesiodistally and from the proteins was negative. Serum protein electrophoresis labial vestibule to the floor of the mouth anteroposteriorly revealed hypoalbuminemia and hypergammaglobu- (Fig. 1A). On palpation, the inspectory findings were linemia with the absence of monoclonal band (Fig. 1F). confirmed. The lesion was firm in consistency, mobile, These observations were substantial to rule out MM. The nontender, fixed to the underlying tissues, and easily EMP was also ruled out as the involvement of bone was bled on touch. No palpable lymph nodes were observed in the head and neck region. A provisional diagnosis of evident radiographically. pyogenic granuloma was made. For definite recognition of the neoplasm, a diagnostic Computed tomography (Fig. 1B) revealed focal workup was done with a panel of following IHC markers, destruction of the outer and inner cortex of body of namely, CD45, CD20, CD3, CD138, and CD56 described in mandible in the midline associated with large heteroge- Table 1. The IHC analysis for anti-CD45 showed a weak neously enhanced soft tissue lesion measuring 40 × 30 × positivity (Fig. 2A), whereas negative immunostain- 30 mm APXTSXCC (anteroposteriorly, transversely, and ing was obtained for anti-CD20 (Fig. 2B) and anti-CD3 coronal) abutting the tongue posteriorly and extending (Fig. 2C) respectively, that enabled to rule out NHL. An up to skin anteriorly with loss of central incisors. Ill- intense membrane positivity was obtained with anti- defined lytic areas of various sizes in regions of ramus, CD138 (Fig. 2D) which further implicated a plasmacytic condylar process, hard palate, and alveolar process of malignancy. This finding helped narrow down to two the maxilla with focal-eroded regions were observed. neoplasias of interest, namely, PBL and SPB. On obtain- Routine hematological investigations revealed a hemoglo- ing a positive immunostaining with anti-CD56 (Figs 2E bin concentration of 11.5 gm%, white blood cell count of and F), a final diagnosis of SPB was made with clinico- 5,260/mm3, platelet count of 2.09 lakhs/mm3, erythrocyte pathologic correlation. sedimentation rate of 13 mm/h, and packed cell volume Following the excision, the patient reported a month of 35% respectively. later, with a recurrent lesion. Although antiretroviral An incisional biopsy was performed under aseptic medication was prescribed, he had not started with the conditions, which affirmed histopathological features of same. Following this, chemotherapy was planned. pyogenic granuloma like regions of inflamed vascular stroma comprising numerous dilated blood vessels with DISCUSSION endothelial proliferation and dense inflammatory cells Plasmacytic malignancies are deceptive and challeng- predominantly lymphocytes and plasma cells (Fig. 1C). ing to diagnose. The present case initially mimicked a Following the incisional biopsy, the patient reported with pyogenic granuloma clinically. The same was confirmed an enlarged lesion in a span of 10 days (Fig. 1D). Consid- histopathologically due to the superficial nature of biopsy. ering the size of the lesion and its immediate recurrent However, an appropriate deeper biopsy would have potential, thorough serological survey was performed. enabled to identify the lesion as a round cell tumor. Investigations for HIV-1 and 2 antibodies by enzyme- The SPB, EMP, and MM result from uncontrolled linked immunosorbent assay, Tridot, and Vitros showed plasma cell proliferation that exhibits overlapping clinical reactivity for HIV-1 antibody as per the National Aids and histologic features; it may often lead to a diagnostic Control Organization guidelines. Serological investiga- dilemma and mislead the clinicians. However, the sero- tions for hepatitis B and C using surface antigen of the logical investigations and histopathology with IHC can hepatitis B virus and hepatitis C virus were negative. be utilized to arrive at an accurate diagnosis to adopt Excisional biopsy of the exophytic growth was per- the indicated treatment strategy to improve treatment formed; on microscopic examination, the sections revealed outcomes. sheets of lymphocytes with varying sizes. The round cells The SPB affects <5% of patients with plasma cell exhibited atypical features, such as pleomorphism, large myeloma with a predilection of 65% in males and

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Diagnostic Panel of Markers CD45, CD20, CD3, CD138, and CD56 for Oral Solitary Plasmacytoma of Bone

A B C

D E F Figs 1A to F: (A) Solitary exophytic growth in the lower front tooth region; (B) computed tomography scan showing focal destruction of outer and inner cortex of body of mandible in the midline associated with large heterogeneously enhanced soft tissue lesion; (C) hematoxylin and eosin stain showing a fibrinous exudate with underlying dilated blood vessels and endothelial proliferation (100×); (D) recurrent lesion in the lower front tooth region following incisional biopsy; (E) hematoxylin and eosin stain showing sheets of round cells with pleomorphism, large, and hyperchromatic nuclei (arrows indicate plasmacytoid cells with atypical features like pleomorphism, large, and hyperchromatic nuclei) (400×); and (F) serum protein electrophoresis showing hypoalbuminemia and hypergammaglobulinemia with absence of monoclonal (M) band

Table 1: Immunohistochemistry panel details employed in the In 2003, the International Myeloma Working Group 5,6 present case (IMWG) published criteria for the classification of mono- IHC Pathological state with positive Region of stain clonal gammopathies, MM, and related disorders recog- marker staining localization nizing SPB, EMP, and multiple solitary plasmacytomas CD45 Pan lymphocytic marker11 Cell membrane, cell surface11,21 (± recurrent) as distinct entities (Table 2). For SPB, the CD3 T-cell neoplasms11 Cell surface features considered are isolated area of bone destruc- CD20 Normal and neoplastic B cells11 Cell surface tion due to clonal plasma cells, bone marrow plasma CD138 Plasmacytic malignancy12 Cell membrane cell infiltration not exceeding 5% of all nucleated cells, 15 CD56 Plasma cells exhibiting cellular atypia Cell membrane absence of further osteolytic bone lesions or other tissue involvement (i.e., no evidence of systemic plasmacytoma), 35% in females, and the median age of presentation absence of anemia, hypercalcemia, or renal impairment is a decade younger than that of subjects diagnosed attributable to myeloma, low concentrations of serum, with MM.5-7 The SPB may involve any bone, but it has or urine monoclonal protein (i.e., myeloma protein), and 6 a predisposition for the red marrow containing axial absence of monoclonal band. The present case was in skeleton. Spinal disease is observed in 34 to 72% of cases. accordance with the above findings and MM was ruled The thoracic vertebrae are most commonly involved, out. The EMPs are localized plasma cell neoplasms that followed by lumbar, sacral, and cervical vertebrae. The present as soft tissue lesions. The EMP was ruled out due rib, sternum, clavicle, or scapula is involved in 20% of to bone involvement that presented with lytic areas caused cases with involvement of mandible being a rare event. by a single lesion. Differences between EMP and SPB are An analysis of the surveillance, epidemiology, and end shown in Table 3. results database from 1992 to 2004 demonstrated that A noticeable feature in the present case was hyper- the incidence of MM (n = 23.544; incidence rate (IR) gammaglobulinemia and hypoalbuminemia, which is 5.35/100,000 person years) is 16 times higher than SPB consistent with the investigation by Sharma et al,7 who overall (n = 1543; IR = 0.34), and incidence of SPB was reported a case of SPB. Chronic infections may be a cause 40% higher than that of EMP (p < 0.0001).5,8 of hypergammaglobulinemia. Studies on animal models World Journal of Dentistry, January-February 2018;9(1):53-58 55 Marin Abraham et al

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D E F Figs 2A to F: Immunohistochemistry of (A) tumor cells showing weak positivity for CD45 (400×); (B) tumor cells showing negative staining for CD20 (100×); (C) tumor cells showing negative staining for CD3 (100×); (D) tumor cells showing strong membrane positivity for CD138 (400×); (E) tumor cells showing positivity for CD56 (100×); and (F) plasmacytic cells showing strong positivity for CD56 (200×)

Table 2: The IMWG diagnostic criteria of SPB, EMP, and Table 3: Differences between SPB and EMP19 multiple solitary plasmacytomas (±recurrent)6 Solitary plasmacytoma Extramedullary Diagnosis Criteria Parameter of bone plasmacytoma Solitary No M-protein in serum and/or urine Site of Axial skeleton— Head and neck—nasal occurrence vertebra and skull cavity and nasopharynx plasmacytoma Single area of bone destruction due to clonal Progression Poor prognosis— Comparatively better of bone plasma cells to MM significantly high prognosis—subjects with Bone marrow not consistent with MM (plasma 65–84% in 10 years EMP that progressed to cells <5%) and 65–100% in 15 MM had a 100% 5-year Normal skeletal survey (and MRI of spine and years, median time to survival rate as compared pelvis if done) progression to MM is with 33% for SPB No related organ or tissue impairment 2–3 years Effect of RT Long-term disease-free Long-term disease-free Extramedullary No M-protein in serum and/or urine application survival is observed in survival is observed in plasmacytoma Extramedullary tumor of clonal plasma cells 30% patients 65% patients Normal bone marrow Diagnostic Solitary bone lesion Tissue biopsy-indicating Normal skeletal survey criteria confirmed by skeletal monoclonal plasma cell No related organ or tissue impairment survey, plasma cell histology, bone marrow infiltration proven by plasma cell infiltration Multiple solitary No M-protein in serum and/or urine biopsy, normal bone <5% of all nucleated cells, plasmacytomas More than one localized area of bone marrow biopsy (<10% absence of osteolytic (± recurrent) destruction or extreme tumor of clonal plasma plasma cells), and bone lesions or other cells which may be recurrent lack of myeloma- tissue involvement MRI: Magnetic resonance imaging related organ without proof of myeloma, dysfunction hypercalcemia or renal have proved that lingering of viruses within the body failure, and low-serum M protein concentration can cause hypergammaglobulinemia, and if viruses are Treatment Surgical excision and Surgical excision cleared quickly, they lead to only a transient increase in RT immunoglobulin G. Impairment in cytokine secretion RT: Radiotherapy can also cause hypergammaglobulinemia. Increased serological levels of interleukin (IL)-21, interferon-γ, IL-6, and In the present case, the patient was seropositive for IL-17 have been observed in numerous lesions associated HIV-1 antibody. The NHL was considered as a differen- with autoimmunity-related hypergammaglobulinemia.9 tial diagnosis as it is the most common neoplasm in HIV 56 WJD

Diagnostic Panel of Markers CD45, CD20, CD3, CD138, and CD56 for Oral Solitary Plasmacytoma of Bone patients in India affecting about 10% of the individuals.10 plasma proliferative disorder.6 The SPB is an antecedent Thereby, CD45, CD3, and CD20 were considered for evalu- to MM, with its progression to the latter lesion usually ation. However, a negative immunostaining by CD45, within 3 years that is indicative of a poorer prognosis and CD3, and CD20 helped to rule out NHL. Expression of can exhibit an unusual involvement of soft tissues. The CD45 is observed in hematopoietic cell lines, unnoticed EMP is usually encountered in the head and neck, with in nonhematopoietic cell lines and also in normal and less aggressive features when compared with SPB.17 It is malignant nonhematopoietic tissues. Therefore, CD45 essential to diagnose SPB accurately; the monoclonal or aids to identify lymphoid neoplastic cells from nonhema- aberrant plasma cell phenotype should be demonstrated topoietic undifferentiated neoplasms. The CD3 marker is with useful IHC markers18 and serological investigations. highly specific for T cells; it is appreciated in majority of According to the Durie and Salmon staging system, SPB T-cell neoplasms; CD20 is a differentiation antigen of B is regarded as Stage I myeloma wherein hemoglobin is cells with its expression being restricted to normal and >10 g/dl, with normal level of serum calcium, normal 19 neoplastic B cells.11 bone structure, and low M component. In addition to the above investigations, we also per- The SPB can be treated with surgical excision, radio- formed an IHC staining with CD138 to identify if the therapy, and chemotherapy to reduce the size of the neoplastic lesion was of plasmacytic origin. An intense lesion. A regular skeletal survey is essential to assess the 20 membrane positivity was observed, and similar findings prognosis due to the rarity of SPB. were identified by Baad et al3 in their report of SPB in the mandible. The CD138 is expressed on the surface of CONCLUSION mature epithelial cells and normal and neoplastic plasma Immunophenotyping plays a pivotal role for a precise cells. It plays an important role in the evaluation and diagnosis in rare neoplasias like the plasmacytic malig- characterization of plasma cell dyscrasias.12 nancies. The CD3, CD20, and CD45 are known as the The PBL was also considered as a possible differential Pan Lymphoma Cocktail. A weak expression of CD45 is diagnosis. It exhibits characteristic clinical features like observed in plasma cell dyscrasias compared with B- and affinity toward oral cavity with a predilection to sites, T-cell lymphomas. The CD138 expresses intense staining such as jaw and palate. Histologically, it presents features with the plasma cell population. The CD56 is frequently like large polygonal plasmablastic cells with abundant used to distinguish abnormal plasma cells from the basophilic cytoplasm and large eccentric nuclei. It is normal counterparts as it stains the former positive and a high-grade B-cell lymphoma and does not express can be correlated with poor disease prognosis. Serological CD56.13,14 The present case showed moderate positiv- investigations can aid in distinguishing among plasma ity with CD56, which supported with the diagnosis of cell dyscrasias combined with an IHC panel. SPB excluding the possibility of PBL. The CD56 aids to identify atypical plasma cells in SPB by its expression in REFERENCES the lesional tissue when compared with EMP and other 1. Sekar B, Augustine D, Murali S. Solitary plasmacytoma of plasma cell dyscrasias.15 Studies conducted by Corti et al13 mandible—report of 2 cases. 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