Pseudolymphoma of the thyroid gland. A case report

Lymphoid Structure Presenting as a Hypermetabolic Adrenal Incidentaloma

Adrenal incidentalomas are a frequent cause for consultation in endocrinology. Current guidelines provide an algorithm for their evaluation to determinate the risk of hormonally active or malignant condition. We report a unique case of benign adrenal incidentaloma in a 53-year-old woman with multiple malignancy criteria on contrast-free computed tomography and [18F]fluorodeoxyglucose positron emission tomography-computed tomography, leading to a left adrenalectomy. Histopathologic analysis showed a 15-mm intra-adrenal lymphoid organ localized in the medulla, without any cellular atypia and organized with a capsule and multiple germinal centers. The surrounding adrenal tissue was unremarkable, and the patient did not develop any inflammatory, infectious, or neoplastic disease during the 2 following years. This is the first described case of a well-organized intra-adrenal ectopic lymphoid organ in the absence of any evident stimulus.

OUP accepted manuscript

Reactive lymphoid hyperplasia (RLH) of the liver is an extremely rare benign lesion, which is often misdiagnosed as a malignant liver tumour. We present the case of a 69-year-old man with an incidental liver tumour revealed on the ultrasonography of the kidney-urinary bladder system for benign prostatic hyperplasia. Hepatocyte-specific contrast (gadoxetate disodium) magnetic resonance imaging revealed a round 6-mm lesion, which was hypointense on T1-weighted images, slightly hyperintense on T2-weighted images and highly intense on diffusion-weighted images. Other findings included arterial hyperintensity, venous and delayed hypointensity and a defect in liver segment 6. The patient was diagnosed with hepatocellular carcinoma; laparoscopic partial hepatectomy was performed. Intraoperatively, a 7-mm greyish white solid nodule was observed. In conclusion, it may be difficult to distinguish RLH from other malignant liver tumours. However, it should be considered as a differential diagnosis for small liver lesions in young, female patients without liver cirrhosis.

Pseudolymphoma of the liver: a case report and literature review

Pseudolymphoma is a benign lymphocytic tumor-like lesion, and its occurrence in the liver is rare. Here, we report the case of a 78-year-old woman with pseudolymphoma of the liver. She had a history of tremors for several years. Therefore, she underwent computed tomography (CT) for screening, and liver tumors were incidentally identified. She did not have any history of liver disease. Liver function test results and tumor marker levels were all within normal limits, and viral markers for hepatitis were negative. Contrast-enhanced CT revealed four nodules measuring up to 13 mm in diameter with ring enhancement in both lobes of the liver. On magnetic resonance imaging, the lesions showed slightly high intensity on T2-weighted images and high intensity on diffusion-weighted images. Because of atypical imaging findings, the tumors could not be definitively diagnosed. Therefore, we performed laparoscopic limited resection of segments 2, 3, 4, and 8 of the liver. The final pathological diagnosis was pseudolymphoma of the liver. The patient has had no signs of recurrence for 6 months after the surgery. Although pseudolymphoma of the liver is rare, it is necessary to consider it in the differential diagnosis of a liver tumor.

Reactive lymphoid hyperplasia of the thyroid followed by systemic autoimmune diseases: a case report

Introduction

Reactive lymphoid hyperplasia is a benign nodular lesion characterized by marked proliferation of non-neoplastic, polyclonal lymphocytes forming follicles. The lesion is found in various organs such as skin, orbit, lung, gastrointestinal tract, and liver. However, reactive lymphoid hyperplasia in the thyroid gland is extremely rare. Here, we present an interesting case of reactive lymphoid hyperplasia in the thyroid, which suggests the nature of the disease.

Case presentation

A 74-year-old Japanese man was referred to our institute because of a growing well-demarcated irregular-shaped mass in the right lobe of the thyroid. Malignant lymphoma was suspected by cytology, and right lobectomy was conducted. A final diagnosis of reactive lymphoid hyperplasia was made by the intimate investigation of the surgical specimen, with evidence of polyclonal and non-neoplastic lymphatic proliferations forming follicles with an active germinal center. After an initial uneventful postoperative course, our patient developed severe symptoms of systemic rheumatic arthritis, and alterations in autoimmune reaction, including clinically overt chronic thyroiditis, were identified.

Conclusions

Our case demonstrated important clinical information on reactive lymphoid hyperplasia of the thyroid, and suggested the importance of differential diagnosis, and possible close correlation between systemic autoimmune disorder and the disease.

Reactive lymphoid hyperplasia of the liver and pancreas. A report of two cases and a comprehensive review of the literature

BACKGROUND

Reactive lymphoid hyperplasia (RLH) is a rare non-neoplastic extranodal pathology with exceedingly rare occurrence in the liver and pancreas. We present two cases of hepatic RLH, one which had coinciding pancreatic involvement. To the best of our knowledge, concomitant hepatic and pancreatic RLH has not been previously reported. We also present a comprehensive review of the literature on hepatic and pancreatic RLH.

METHODS

An extensive literature search for all published reports on hepatic or pancreatic RLH was conducted. Data on clinical, radiographic and histopathological features were extracted in addition to therapeutic options and outcomes.

RESULTS

Forty-two hepatic and three pancreatic cases of RLH were described in the literature. The mean age of hepatic cases was 58 years, with a male-to-female ratio of above 1:7. Almost 25% of cases were associated with internal malignancy. Four hepatic cases were managed through active observation. The remainder (84%) underwent surgical resection. Due to their small number, no meaningful analysis could be made on the pancreatic cases. No recurrences were identified in any of the reported cases.

CONCLUSION

RLH should be considered in the diagnosis of hepatic nodules where biopsies fail to demonstrate malignant cells. Confirmed RLH lesions should be managed by active observation. Investigation and treatment of any potential source of lymphoid reactivity should be undertaken. More reports on pancreatic RLH need to be studied prior to drawing any useful recommendations on its management.

Reactive lymphoid hyperplasia of the liver in a patient with colon cancer: report of two cases

BACKGROUND

Reactive lymphoid hyperplasia (RLH) of the liver is very rarely reported, and we encountered two cases of RLH of the liver in a patient with colon cancer.

CASE PRESENTATION

In the first case, a 77-year-old woman was admitted for the surgical removal of a ascending colon cancer. A hepatic tumor in the left lobe was concurrently revealed by computed tomography (CT), and magnetic resonance imaging (MRI). The appearance suggested liver metastasis. Right hemicolectomy and partial hepatectomy were performed. On histopathological examination, lymphoid follicles with germinal centers were seen in the tumor-like lesion, and remarkable lymphoid infiltration with germinal centers was seen in the portal area around the nodule. Immunohistochemical studies revealed polyclonality of infiltrating lymphocyte. Consequently, this nodular lesion was diagnosed as RLH of the liver. In the second case, a 64-year-old woman who had a radical right hemicolectomy for stage II ascending colon cancer 10 years ago was admitted with dysuria. A hepatic tumor in the left lobe was concurrently revealed by CT and MRI, suggesting hepatocellular carcinoma. A left lateral segmentectomy was performed. Microscopically, this lesion revealed the almost same findings as the first case, so this nodular lesion was diagnosed as RLH of the liver.

CONCLUSION

Our two cases were the first report of RLH of the liver accompanying colon cancer. Because there are a very few cases, so it is not clear whether the malignancies were involved in the onset of RLH. But we believe that new factors involved in the onset mechanism of RLH may be identified by carefully monitoring the clinical course of our two patients.

Thyroid low-grade B-cell lymphoma (MALT type) with extreme plasmacytic differentiation: Report of a case diagnosed by fine-needle aspiration and flow cytometric study

We describe a case of thyroid marginal-zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) with extreme plasmacytic differentiation in an 80-year-old woman who had presented with a rapidly growing thyroid swelling. The diagnosis was initially suspected on fine-needle aspiration (FNA) and subsequently confirmed by flow cytometric analysis of the aspirated material. The smears revealed features of Hashimoto's thyroiditis admixed with large numbers of atypical large plasmacytoid lymphoid cells accompanied by variable numbers of small lymphocytes and mature plasma cells. The differential diagnosis of a predominantly plasmacytic smears on FNA of the thyroid is discussed herein, with emphasis on the role of immunophenotypic studies to exclude or confirm the diagnosis of lymphoma.