Plasma Cell Granuloma of the Thyroid: Review of an Uncommon Entity

Role of myofibroblasts in oral plasma cell granuloma: Immunohistochemical evaluation of α-SMA and ALK in a retrospective study of 30 cases

INTRODUCTION

Oral plasma cell granuloma (OPCG) is a rare reactive lesion with generally benign yet occasionally aggressive behavior. Myofibroblasts are important in many physiologic, and pathologic conditions. The role of myofibroblasts in the clinical behavior of OPCG was assessed as well as its usefulness in differentiating this lesion from the inflammatory myofibroblastic tumor mimicking plasma cell granuloma.

MATERIAL AND METHODS

This retrospective study included 30 paraffin blocks of OPCG. Immunohistochemical evaluation of alpha-smooth muscle actin (α-SMA) and Anaplastic lymphoma kinase (ALK) antibodies was performed. The mean area of positive expression was calculated and scored semiquantitatively with clinicopathologic correlations.

RESULTS

Most of the cases were clinically non-aggressive. Alveolar bone resorption was observed in nine cases, two of them showed severe resorption and stromal fibrosis. Negative α-SMA was observed in 70% of cases showing a predominance of plasma cells in the stroma. All cases of stromal fibrosis revealed positive α-SMA of a weak percentage. A statistically significant difference was observed between α-SMA expression and the clinicopathologic variables. Negative ALK expression was noted in all cases.

DISCUSSION

Myofibroblasts were infrequently found in OPCG. Remarkably, the aggressive behavior in cases with intense fibrosis was related to the existence of myofibroblasts even of non-neoplastic nature and minimal amount. The number of myofibroblasts and their nature assessed via α-SMA and ALK immunohistochemical expression respectively might be valuable in predicting the biological behavior of OPCG and may hold diagnostic significance in challenging OPCG cases that might mimic inflammatory myofibroblastic tumor.

Analgesic, anti-inflammatory and acute oral toxicity profile of leaf and bark extracts of Albizia procera

Background

Pain and inflammation are associatory events in cancer, diabetes, cardiovascular diseases, arthritis and other chronic diseases. Corticosteroids, non-steroidal anti-inflammatory drugs exert potential side effects on long term use. This study was aimed to investigate the acute oral toxicity, anti-inflammatory and analgesic activities of leaf and bark extracts of Albizia procera in experimental animal models.

Methods

Ethyl acetate, ethanol, and hydroalcoholic extracts of Albizia procera (leaf and bark) were subjected for acute oral toxicity, anti-inflammatory and analgesic screening. Carrageenan and cotton pellet granuloma models were used to assess acute and chronic anti-inflammatory effects, respectively. Intraplanar formalin test was used to assess the analgesic activity.

Results

All the extracts of Albizia procera were found to be well-tolerated up to 2000 mg/kg in female rats. Ethanolic leaf (ETLE) and bark (ETBE) of Albizia procera showed anti-inflammatory actions. But, only ETBE produced significant protection in chronic inflammation and analgesic activity.

Conclusion

In summary, Albizia procera possess significant anti-inflammatory and analgesic properties. This study adds evidence on the traditional use of Albizia procera plant for treating painful inflammatory disorders.

Cross-segment spinal plasma cell granuloma:a case report

BACKGROUND

Plasma cell granuloma (PCG) is a rare non-neoplastic entity, with the precise etiology remaining unclear. Vertebra-affected spinal PCG has not been reported yet. This report presented a case with cross-segment spinal PCG in thoracolumbar region.

CASE PRESENTATION

A 32-year-old male patient presented to the authors' hospital since his health check-up results showed osteolytic lesions in the thoracolumbar spine. He felt asymptomatic throughout the course. Radiological examination revealed destructive changes at T12 and L1 vertebrae. Whereas laboratory examination excluded malignant tumor. The results of routine incisional biopsy remained inconclusive, thereby necessitating complete excision of the lesions. Finally, the infiltration of plasma cells observed by pathological examination of the surgical specimen confirmed the diagnosis of PCG.

CONCLUSIONS

To the authors' knowledge, this was the first case of cross-segment spinal PCG with osteolytic property. The possibility of PCG should be considered for the diagnosis and differential diagnosis of an osteolytic lesion in the spine. Since the etiology of PCG is unknown, the disorder was confirmed based on excluded diagnosis. Surgical resection is recommended both for the definite diagnosis and treatment of spinal PCG.

ALK-1-positive inflammatory myofibroblastic tumor of the thyroid complicated by Hashimoto's thyroiditis: report of a rare case and a literature review

BACKGROUND

Inflammatory myofibroblastic tumors (IMTs) of the thyroid are extremely rare soft-tissue tumors. In the literature, IMTs are sometimes called plasma cell granulomas (PCGs) or inflammatory pseudotumors, which often causes ambiguity. To date, 17 cases of PCGs and five cases of thyroid IMTs have been reported. These cases reveal that IMTs of the thyroid are often negative for the anaplastic lymphoma kinase (ALK-1) gene. To provide further information on this rare lesion, we present a case of an ALK-1-positive thyroid IMT and a review of IMTs of the thyroid.

CASE PRESENTATION

A 34-year-old Chinese woman presented with a painless neck mass that had persisted for over a month. Ultrasonography revealed a 4.28 × 2.53 cm² hypoechoic mass, in the left lobe of the thyroid gland. Serum levels of thyroglobulin and anti-thyroglobulin antibodies were high. Subsequently, left lobectomy was performed. Macroscopically, the lesion was a gray-brown nodular mass with a partial envelope. Histologically, two different lesion types were observed. The first lesion showed classic spindle cell proliferation, with spindle cells arranged in fascicles, accompanied by mature inflammatory cells. The other lesion showed a large number of infiltrating lymphocytes, with lymphoid follicles in the remaining thyroid gland, which was atrophic. Immunohistochemical staining showed that the spindle cells were negative for CK19, CyclinD1, Gelectin-3, EMA, CD34, S100, Bcl-2, and STAT-6, but strongly positive for ALK-1, vimentin, and TTF1. CK was focally expressed, and the Ki-67 index was 5%. A diagnosis of IMT was proposed according to immunohistochemical findings and morphology. Hashimoto's thyroiditis was confirmed according to serum levels of thyroglobulin and anti-thyroglobulin antibodies and morphology. The patient did not receive adjuvant therapy. She remained alive without disease recurrence for 10 months after lobectomy.

CONCLUSIONS

IMTs should be considered in the diagnosis when spindle cell proliferation accompanied by mature inflammatory cells is observed, spindle cells are mildly atypical, and myofibroblast differentiation is present in the thyroid. A uniform diagnostic term is crucial to avoid ambiguity. Clinicians and pathologists should be aware of the necessity for long-term follow-up, especially in ALK-positive cases. The therapeutic potential of ALK-1 positivity should be explored further.

A Case Report of Thyroid Plasmacytoma and Literature Update

Plasmacytomas of the thyroid gland are rare, whether or not they arise as solitary (primary) lesions or secondary to systemic multiple myeloma. Here, we present the case of a 71-year-old female presenting with goiter and Hashimoto’s thyroiditis, in whom the subsequent histopathological diagnosis of plasmacytoma was a surprise. In presenting this case, we summarize the last 25 years of literature on thyroid plasmacytoma and review the salient clinicopathological characteristics, differential diagnoses, management, and outcomes of this rare condition.