Solitary extramedullary plasmacytoma of the parotid gland imaged with 18F-FDG PET/CT

Unilateral Parotid Gland Involvement of Relapsed Acute Lymphoblastic Leukemia Demonstrated by 18F-FDG PET/CT

The involvement of the parotid gland by acute lymphoblastic leukemia in extramedullary relapse is considered a rare occurrence. A 5-year-old girl with acute lymphoblastic leukemia presented with peripheral facial paralysis, and her symptoms remained unrelieved despite symptomatic treatment. 18F-FDG PET/CT showed hypermetabolic activity not only in the left parotid gland but also in multiple cervical lymph nodes, confirming a relapse of T-cell acute lymphoblastic leukemia.

18 F-FDG PET/CT in Solitary Extramedullary Plasmacytoma of the Penis

ABSTRACT

A 72-year-old man presented with a painless penile mass for 3 months. Contrast-enhanced CT revealed heterogeneous enhancement, whereas 18 F-FDG PET/CT displayed inhomogeneous 18 F-FDG accumulation in the lesion without other abnormal activity. The histopathological examination from biopsied specimen confirmed the diagnosis of a plasmacytoma. However, the subsequent tests, including serum/urine immunofixation electrophoresis, serum/urine free light chain assay, and bone marrow smear/biopsy, did not show any abnormalities. The conclusive diagnosis was a solitary extramedullary plasmacytoma of the penis.

Extramedullary Plasmacytoma of the Retroperitoneum Detected on 18 F-FDG PET/CT

ABSTRACT

Solitary retroperitoneal extramedullary plasmacytoma is a rare neoplasm. A 67-year-old man presented with abdominal pain and left leg weakness. Abdominal CT revealed a large mass in the left retroperitoneum, which demonstrated increased metabolic activity on subsequent 18 F-FDG PET/CT imaging. Furthermore, the patient's serum protein electrophoresis showed positive M-protein results. Pathological examination of the biopsied specimen confirmed the diagnosis of extramedullary plasmacytoma.

Extramedullary Plasmacytoma: Hepatic Lesions and Enlarged Lymph Nodes With Intense 18F-FDG Uptake Mimicking Metastases

ABSTRACT

A 66-year-old woman having intermittent abdominal distention for 2 months was referred to our hospital. An enhanced abdominal CT scan showed multiple hepatic lesions, suspected of metastases. An 18F-FDG PET/CT scan, which was performed to seek primary tumor, showed multiple lesions with intense 18F-FDG uptake in the liver and lymph nodes located in cardiophrenic angle, abdominal cavity, and retroperitoneal space. All 18F-FDG-avid lesions were suspected of metastases. However, no suspected primary tumor was identified by the 18F-FDG PET/CT scan, which prompted the liver biopsy. Pathologic analysis revealed the presence of plasmacytoma.

Solitary extramedullary plasmacytoma of the parotid gland in a patient with mixed connective tissue disease

Solitary extramedullary plasmacytomas of the head and neck region are rare entities. Very few have been described in the parotid gland. They can clinically and radiologically mimic the rather common benign tumors of the parotid gland (pleomorphic adenoma and Wharthin's tumor), and subsequently the need careful consideration by the involving surgeon and pathologist is needed for a proper diagnosis. In the present study, a case of solitary extramedullary plasmacytoma in the left parotid gland of a 55-year-old patient with mixed connective tissue disease is reported, along with the relevant clinical, imaging, operative, and histopathological findings. Postoperative hematological investigation to confirm the singularity of the lesion was performed. Complementary treatment with radiotherapy was followed. Disease-free, 1 year follow up is also presented.

FDG PET/CT Imaging of Pancreatic Plasmacytoma

A 56-year-old man underwent F-FDG PET/CT to evaluate possible pancreatic cancer, which was revealed by CT. The images showed a solid lesion with peripherally increased FDG activity in the tail of the pancreas, as well as hypermetabolic lesions in the lumbar spine and rib. Pathological examination following lumbar biopsy demonstrated multiple myeloma. Five months after chemotherapy, follow-up FDG PET/CT showed cystic change in the pancreatic lesion without elevated metabolism.

Recurrence of Extramedullary Plasmacytomas Involving Lymph Nodes and Pancreas Revealed by 68Ga-DOTATATE and 18F-FDG PET/CT

A 40-year-old man with history of extramedullary plasmacytoma in nasal cavity presented with right submandibular mass for 3 months. F-FDG PET/CT demonstrated mild radioactivity in the right submandibular mass, pancreatic mass, and lymph nodes in the abdomen and left hilum of the lung. To differentiate from pancreatic neuroendocrine tumor, Ga-DOTATATE PET/CT was performed. The above lesions were TATE avid, and additional lesions with intense radioactivity were also detected in the right internal mammary node and intrapericardial node. Finally, biopsy of the right submandibular mass confirmed recurrence of extramedullary plasmacytoma.

The role of initial 18F-FDG PET/CT in the management of patients with suspected extramedullary plasmocytoma

Background

Extramedullary plasmacytoma (EMP) is a plasma cell malignancy that originates in soft tissues without evidence of systemic spread, and its management differs from other plasma cell neoplasms. The purpose of the present study was to evaluate the role of initial ¹⁸F-FDG PET/CT in the management of patients with clinical suspected EMP.

Methods

¹⁸F-FDG PET/CT scans performed in 21 patients (M/F = 12/9, mean age 51.1 ± 15.3 years) with clear suspicion of EMP from 2006 to 2015 were analysed retrospectively. The detection of new lesions and the change in treatment were evaluated.

Results

PET/CT detected new lesions in 38.1% (8/21) of patients with 17 lesions, and lymph nodes were the most common site, accounting for 70.6% (12/17) of all lesions, followed by bone (n = 2), and less frequently, breast (n = 1), lung (n = 1), and stomach (n = 1). These findings resulted in treatment changes in 7 patients with EMP. Among these, 4 patients had major treatment changes and 3 patients had minor changes. Of the 21 patients, progression to MM was observed in 8 patients (8/21, 38.1%). In univariate analysis, tumour size > 4 cm and partial response (PR) after treatment were significant prognostic factors for Progression-free survival (PFS).

Conclusions

Our data indicated that ¹⁸F-FDG PET/CT is helpful in the detection of additional lesions throughout the body, including lymph node involvement and distant additional lesion, which may have resulted in treatment change.

Primary extraosseous plasmacytoma of the parotid gland: A case report and literature review

Extraosseous plasmacytoma (EOP) is an uncommon malignant tumour that is characterised by the monoclonal proliferation of abnormal plasma cells in soft tissue; however, EOP lacks the defining features of multiple myeloma or medullary plasmacytoma. Although the majority of EOP lesions occur in the head and neck, EOP of the parotid gland is extremely uncommon. The present study aimed to explore the clinical features of parotid plasmacytoma, in addition to the diagnostic and therapeutic options for its management. Using the Medline database, a search was conducted for articles published on the topic of ‘parotid plasmacytoma’ up until the year 2016. A total of 20 cases were evaluated, including 19 clinical cases from the literature and 1 new clinical case from our hospital. Among the 19 previously published cases, the mean age at the time of diagnosis of EOP was 65.1±10.9 years (range, 38–78 years). Plasmacytomas were located unilaterally in all cases: On the right side in 9 patients (47.4%), on the left side in 10 patients (52.6%). Treatment included chemotherapy in 3 cases, radiotherapy in 11 cases and surgical removal in 15 cases. The diagnosis of EOP is based on the presence of a localised tumour comprising monoclonal plasma cells, and EOP is identical to multiple myeloma in this regard; however, EOP, in contrast to multiple myeloma, does not exhibit the signs that are indicative of disseminated disease, such as additional lesions on skeletal radiological examination, plasmacytosis in the bone marrow, and hypercalcaemia, anaemia, or renal failure. Thus, EOP must be considered in the differential diagnosis of parotid gland lesions in order to avoid confusion with other tumoural diseases.

Solitary Osteogenic Sternum Plasmacytoma on Bone Scintigraphy and FDG PET/CT

We reported a rare solitary osteogenic sternum plasmacytoma case. A 49-year-old woman experienced progressing pain in the sternum for 2 years. Abnormal Tc-MDP accumulation and increase in F-FDG uptake (SUVmax, 4.4) were co-localized with the osteogenic lesion in the sternum body detected by diagnostic CT. The lesion was histologically confirmed as plasma cell neoplasm suggestive of plasmacytoma. The patient had good response to radiotherapy.