Case report of 18F-FDG PET/CT features of hypoglycemic encephalopathy.

RATIONALE: Hypoglycemia may cause diverse neurological manifestations, ranging from focal neurological deficits to irreversible coma. Severe and persistent hypoglycemia can lead to hypoglycemic encephalopathy (HE). Imaging findings of HE at different stages of 18F-FDG positron emission tomography/computed tomography (PET/CT) have rarely been reported. Herein, we describe a case of HE occurring in the medial frontal cortex, cerebellar cortex, and dentate nucleus using 18F-FDG PET/CT images from different periods. 18F-FDG PET/CT has a high value in displaying the lesion range and indicating the prognosis. PATIENT CONCERNS: A 57-year-old male patient with type 2 diabetes (T2D) was transferred to the hospital with a history of unconsciousness for 1 night. The patient showed a significant decrease in blood glucose levels. DIAGNOSES: The patient was initially diagnosed with a hypoglycemic coma. INTERVENTIONS: The patient subsequently underwent a comprehensive treatment. The 18F-FDG PET/CT examination on the fifth day after admission revealed a significant symmetrical fluorodeoxyglucose (FDG)-positive accumulation in the bilateral medial frontal gyrus, cerebellar cortex, and dentate nucleus. A follow-up PET/CT examination 6 months later revealed hypometabolism in the bilateral medial frontal gyrus and no abnormalities in FDG uptake in the bilateral cerebellar cortex and dentate nucleus. OUTCOMES: The patient condition was stable 6 months later, with a slow response, memory deterioration, occasional dizziness, and episodes of hypoglycemia. LESSONS: HE lesions with a high metabolic status may be related to a metabolic compensation mechanism in response to gray matter loss. Some of the more severely damaged cells eventually die even after the blood sugar levels return to normal. Less damaged nerve cells can be recovered. 18F-FDG PET/CT has high value in indicating the lesion range and prognosis of HE.

Primary follicular lymphoma in the renal pelvis: A rare case report.

BACKGROUND: Follicular lymphoma (FL) is more common in lymph nodes, while primary extranodal lymphomas are rare. Urinary tract lymphoid neoplasms are extremely rare, accounting for less than 5% of all extranodal lymphomas. Only one case of FL from the renal pelvis has previously been reported. CASE SUMMARY: A 70-year-old male patient with a history of esophageal cancer visited our hospital for follow-up examination. Abdominal computed tomography revealed a malignant mass in the right renal pelvis. The whole-body positron emission tomography/computed tomography showed a significant increase in fluorodeoxyglucose uptake of this soft tissue mass and no abnormal fluorodeoxyglucose uptake in the esophageal wall. The patient underwent radical resection of a malignant tumor in the right kidney, which was confirmed by postoperative pathology to be FL. The patient received no radiation or chemotherapy after surgery, and no recurrence of lymphoma or other malignant tumors was found at the 1-year follow-up. CONCLUSION: Extranodal FL is more common in the skin and gastrointestinal tract but rarely occurs in the urinary tract. This is the second report of primary renal FL. Localized extranodal FL is expected to have a favorable prognosis and can be cured by local resection.

18F-FDG PET/CT imaging for aggressive melanotic schwannoma of the L3 spinal root: A case report.

RATIONALE: Melanotic schwannoma (MS) is an unusual variant of a nerve sheath neoplasm that accounts for less than 1% of all primary peripheral nerve sheath tumors. Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) has unique value in detecting malignant MS lesions. To date, only 4 cases of MS with hepatic metastasis have been reported. Herein, we report the fifth case, which is the first reported patient with MS of Asian ethnicity with hepatic metastasis. PATIENT CONCERNS: A 29-year-old woman with a 1-day history of backache was admitted to our hospital. PET/CT showed a paravertebral heterogeneous soft tissue mass along the spinal nerve at the L2-L3 level with strong FDG uptake, and a nodule with increased FDG uptake in the lateral lobe of the left liver. DIAGNOSIS: A puncture biopsy of the L3 bony destruction and surrounding soft tissue mass was performed. The final diagnosis was spinal MS with hepatic metastasis. INTERVENTIONS: The patient underwent 6 courses of systemic chemotherapy. OUTCOMES: The patient did not receive further treatment for half a year after the end of chemotherapy and recovered well. LESSONS: Unlike conventional schwannomas, which are completely benign, MS has an unpredictable prognosis. It is thought to have low malignant potential, and the malignant type tends to metastasize. FDG PET/CT has a unique and important value in the differential diagnosis of benign and malignant lesions, in detecting occult metastases, monitoring the treatment response, and assessing the prognosis of MS.

Pulmonary mucinous cystadenoma complicated with infection: A rare case report.

RATIONALE: Mucinous cystadenoma is a benign tumor that is commonly found in the pancreas, ovaries, or appendix, but is rarely encountered in the lungs. Worldwide, only a few reported cases of these tumors originate in the lungs. Herein, we analyzed the imaging features of a case of pulmonary mucinous cystadenoma (PMCA). To the best of our knowledge, this is the first reported case of PMCA complicated by significant infection. PATIENT CONCERNS: A 57-year-old man was admitted to our hospital with blood in sputum for more than 2 months. Serum laboratory examination showed significantly elevated leukocyte and tumor marker, carcinoembryonic antigen. Enhanced thoracic computed tomography and whole-body positron emission tomography/computed tomography showed a cystic-solid ill-defined mass in the right upper lung. DIAGNOSIS: The tumor was considered malignant, both clinically and radiologically. INTERVENTIONS: The patient underwent right upper lobe tumor resection and mediastinal lymph node dissection. OUTCOMES: Postoperative specimen pathology was diagnosed as PMCA with infection. The patient was not administered any further treatment. The patient was alive without any recurrence or metastasis of the tumor after 2 years of follow-up. LESSONS: Preoperative diagnosis of PMCA with atypical imaging and clinical manifestations is extremely difficult. This is the first reported case of PMCA complicated by a significant infection that was misdiagnosed preoperatively as a malignancy.

Familial aggregation of subcutaneous panniculitis-like T cell lymphoma: A case report of monozygotic twin brothers.

RATIONALE: Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a rare subtype of cutaneous lymphoma, which was first defined as a clinical entity in 1991 as a cytotoxic T-cell lymphoma preferentially infiltrating subcutaneous tissue. Herein, we report 2 patients of SPTCL who are a pair of twin brothers. PATIENT CONCERNS: The disease afflicted the monozygotic twin brothers at different time with an interval period of 5 years. The older twin brother had disease onset at 27 years of age. In June 2012, he developed prolonged fever accompanied by subcutaneous nodules in the left upper arm and left chest due to unknown origin. The younger twin brother had disease onset at 32 years of age. In June 2017, the younger brother presented with repeated high fever for more than 10 days, accompanied by head distension. DIAGNOSIS: On August 7, 2012, skin biopsy was performed on the lesion of left upper arm of the older twin brother, and then, a diagnosis of subcutaneous panniculitis-like T cell lymphoma (SPTCL) was made. On June 19, 2017, the younger twin brother underwent whole-body fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography for diagnosis. Soon afterwards, abdominal subcutaneous nodule resection and biopsy was performed on June 28, 2018, and the specimen was diagnosed as SPTCL. INTERVENTIONS: For the older brother, a total of 14 systemic chemotherapy sessions were performed from August 16, 2012, to September 21, 2014. For the younger brother, a total of 9 systemic chemotherapy sessions were performed from July 14, 2017, to March 8, 2018, then he was switched to oral chemotherapy with chidamide twice a week for 6 months. OUTCOMES: The older twin brother died in March 2015, the younger brother has recovered well and is no longer receiving any treatment LESSONS:: To the best of our knowledge, twin brothers both having this disease has never been previously reported. Moreover, some of the involved areas are also extremely rare detected by fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography at initial stage. It is beneficial to people to gain some new understanding for SPTCL by this special case and some extremely unusual involved sites in the younger twin brother.

Imaging findings of gastric plexiform fibromyxoma with a cystic change: A case report and review of literature.

RATIONALE: Plexiform fibromyxoma (PF) is an extremely rare mesenchymal tumor of the stomach, and its radiological findings have not been well described. Here, we analyzed the imaging features of a case of PF. To our knowledge, this is a rare reported case with a remarkable cystic change in the imaging literature. PATIENT CONCERNS: A previously healthy 50-year-old woman presented with a 1-day history of abdominal pain. Then, she underwent computed tomography (CT) and magnetic resonance imaging (MRI). A cystic-solid well-circumscribed extraluminal mass was located in the posterior wall of the gastric upper body. The solid portion appeared as heterogeneous attenuation/intensity with progressive enhancement while the cystic region had no enhancement. DIAGNOSES: The potential for malignancy could not be excluded. INTERVENTIONS: Laparoscopic partial gastric resection was performed. OUTCOMES: Based on pathological findings, a diagnosis of PF was made. The patient was alive without any recurrence or metastasis of the tumor after 2 years of follow-up. LESSONS: As far as we know, a gastric PF with a remarkable cystic change has never been reported. Additionally, the tumor exhibited a progressive enhancement pattern which is a characteristic radiographic feature in our case. Our report may help increase the awareness of this rare but important new disease entity.

Primary sarcomatoid carcinoma of the mandibular gingiva: clinicopathological and radiological findings.

Sarcomatoid carcinoma is a rare, malignant biphasic neoplasm with an epithelial and a spindle cell component. Primary sarcomatoid carcinomas arising from mandibular gingiva are known to be extremely rare, with only one case reported to date. Herein, we discuss the radiographic and computed tomographic appearances and pathological features of primary mandibular sarcomatoid carcinoma, which was confirmed by clinicopathology, in a 72-year-old man. In addition, we present a brief review of the relevant literature.

Clinical and computed tomography features of adult abdominopelvic desmoplastic small round cell tumor.

To investigate the clinical and computed tomography (CT) features of desmoplastic small round cell tumor (DSRCT), we retrospectively analyzed the clinical presentations, treatment and outcome, as well as CT manifestations of four cases of DSRCT confirmed by surgery and pathology. The CT manifestations of DSRCT were as follows: (1) multiple soft-tissue masses or diffuse peritoneal thickening in the abdomen and pelvis, with the dominant mass usually located in the pelvic cavity; (2) masses without an apparent organ-based primary site; (3) mild to moderate homogeneous or heterogeneous enhancement in solid area on enhanced CT; and (4) secondary manifestations, such as ascites, hepatic metastases, lymphadenopathy, hydronephrosis and hydroureter. The prognosis and overall survival rates were generally poor. Commonly used treatment strategies including aggressive tumor resection, polychemotherapy, and radiotherapy, showed various therapeutic effects. CT of DSRCT shows characteristic features that are helpful in diagnosis. Early discovery and complete resection, coupled with postoperative adjuvant chemotherapy, are important for prognosis of DSRCT. Whole abdominopelvic rather than locoregional radiotherapy is more effective for unresectable DSRCT.

Primary histiocytic sarcoma of the stomach: a case report with imaging findings.

Histiocytic sarcoma (HS) is a rare malignant neoplasm that originates from a histiocytic hematopoietic lineage characterized by histiocytic differentiation and its corresponding immunophenotypic features. We herein reported a case of primary HS of the stomach which was confirmed through histopathologic examination and immunohistochemical staining. A 52-year-old woman presented with progressive difficulty in feeding and dull pain in the epigastric region. Gastroscopy, endoscopic ultrasonography, double contrast examination, and computed tomography revealed a mass located on the posterior wall of fundus and lesser curvature of the stomach. Microscopically, the cytoplasm of the tumor cells was abundant and eosinophilic. Immunohistochemical staining revealed that the tumor cells were positive for CD45RO and CD68. It is difficult to differentiate HS of stomach from other gastric malignancies by radiological evaluation alone. However, HS may be considered when a protruding and ulcerated mass in stomach shows heterogeneous hypervascular features. To the best of our knowledge, this is the first report in English language literature that emphasizes the imaging findings of human gastric HS.