Esophageal Leiomyoma: A Rare Cause of False-Positive FDG Scans

Uncommon Detection of Leiomyoma in the Penile Corpus Spongiosum Using FDG PET/CT: A Case Report

ABSTRACT

Primary tumors of the penile corpus spongiosum are rare. Hereby we describe the scintigraphic findings of a case of penile leiomyoma within the corpus spongiosum tissue, which was incidentally detected on FDG PET/CT. The benign neoplasm was growing in close proximity to the urethra showing increased focal FDG uptake on sequential PET/CT studies. Subsequently, the patient experienced obstructive urinary symptoms, and the tumor was resected. We concluded that the possibility of neoplasm should be kept in mind while evaluating a patient with persistent focal penile FDG uptake, which may be the first and only manifestation of the disease.

Surgical strategy in abnormally increased Fluorine-18 fluorodeoxyglucose uptake in an asymptomatic lower esophageal submucosal tumor - Report of a case

INTRODUCTION

Leiomyoma is the most common benign tumor of the esophagus (67-80%), it represents 0.4-1% of all esophageal tumors.

PRESENTATION OF CASE

An incidentally discovered gastro-esophageal submucosal tumor was found to have increased fluorine-18-fluorodeoxyglucose (FDG) uptake on positron emission computed tomography (PET/CT). After laparoscopic surgical exploration and local enucleation the tumor turned out to be a benign esophageal leiomyoma.

DISCUSSION

There are few reports of esophageal leiomyomas with a positive uptake on (PET/CT) and even fewer adopting our combination of a minimally invasive approach and frozen section examination as a management plan. Our approach avoided excessive morbid surgical resections and underestimation of a malignant disease.

CONCLUSION

We report this case hoping to expand the existing literature on the topic and to highlight the limitations of PET/CT in guiding the diagnosis and subsequently the management of esophageal submucosal tumors.

Thorax: normal and benign pathologic patterns in FDG-PET/CT imaging

This article describes the normal patterns of thoracic (18)F-fluorodeoxyglucose (FDG) biodistribution, and expands on the role of FDG-PET/computed tomography (CT) for the evaluation of patients suffering from a spectrum of benign pathologic conditions that affect the chest. The discussion addresses the applications of FDG-PET/CT imaging in a wide variety of chest-related disorders. Familiarity with the normal thoracic biodistribution of FDG, coupled with knowledge of the potential nonmalignant causes of increased FDG uptake in the chest, is essential to minimize the incidence of incorrect interpretation of FDG-PET images in daily clinical practice.

Successful enucleation of a fluorine-18-fluorodeoxyglucose positron emission tomography positive esophageal leiomyoma in the prone position using sponge spacer and intra-esophageal balloon compression

Recently, prone position esophagectomy for esophageal cancer is thought to be an easier and safer procedure. Here, we introduced prone position for enucleation of the fluorine-18-fluorodeoxyglucose positron emission tomography (FDG-PET) positive esophageal leiomyoma. The patient was a 47-year-old man with a 4 cm mid-thoracic esophageal submucosal tumor. The tumor was enucleated safely without injury of the esophageal mucosa under the gravity effect of the prone position with use of a sponge spacer and Sengstaken-Blakemore balloon. Postoperative examination revealed that the tumor was a leiomyoma that was positive for smooth muscle actin and negative for CD117. Postoperative course was uneventful and the patient was discharged on day 7 after the operation. The prone position with use of a sponge spacer and Sengstaken-Blakemore balloon was a safer and easier procedure for the enucleation of the esophageal submucosal tumor.

Fluorine-18-fluorodeoxyglucose uptake in a benign oesophageal leiomyoma: a potential pitfall in diagnosis

Positron-emission tomography scans (PET) with fluorine-18-fluorodeoxyglucose ((18)F- FDG) are usually negative in leiomyomas. Two patients underwent a PET that showed an increased (18)F- FDG uptake of the distal oesophagus suggestive for malignancy. Both patients were operated on and histologic examination revealed a benign leiomyoma in both cases. We conclude that oesophageal leiomyomas are a potential cause of a false-positive PET. A high level of caution is needed in these diagnostically challenging cases to prevent unnecessary surgical procedures.

18F-fluorodeoxyglucose PET/CT in a patient with esophageal and genital leiomyomatosis

Diffuse esophageal leiomyomatosis is a rare benign tumor, which can be associated with leiomyoma in female genital tracts involving the uterus, vagina, and vulva. Alport syndrome, an inherited disorder that includes the kidneys, eyes, and sensorineural hearing loss, is also rarely associated with these multiple leiomyomatosis. In our case, (18)F-fluorodeoxyglucose positron emission tomography/computed tomography was used to distinguish esophageal and genital leiomyomatosis from malignant masses.

Clinical significance of performing 18F-FDG PET on patients with gastrointestinal stromal tumors: a summary of a Japanese multicenter study

OBJECTIVE

The aim of this study is to evaluate the clinical significance of performing (18)F-fluorodeoxyglucose (FDG) positron-emission tomography (PET) on patients with gastrointestinal stromal tumors (GISTs).

METHODS

The patient samples for this study were provided by seven PET institutions in Japan. Forty-one patients with pathologically proved GISTs, 24 men and 17 women (mean age 60.3 years, range 26-81 years) were enrolled in this study. Final diagnosis was based on the follow-up imaging at least 3 months after the PET scan or histopathological examinations.

RESULTS

There were eight preoperative cases and 33 follow-up cases in our series. Preoperative cases showed that the sites of primary tumor were the stomach (5 cases, 62.5%), and small intestine (3 cases, 37.5%). One stomach lesion and one small intestine lesion showed negative findings. In follow-up cases, there were 18 PET-negative cases. Among them, two cases were considered as false negative by follow-up imaging. On the other hand, 15 cases showed positive findings at 23 lesions. Most PET-positive cases were considered as true positive except for one false-positive case, who later received surgery and was diagnosed as leiomyoma histopathologically. In 14 cases, PET findings were considered to provide additional information to conventional imaging. In eight cases among them, PET findings were considered to have influenced the decision-making of therapeutic plans.

CONCLUSION

Our data suggest that FDG PET has an incremental value over conventional imaging for the diagnostic and therapeutic management of patients with GISTs in Japan as reported worldwide, and supports its introduction as a routine diagnostic tool for patients with GISTs.

Role of modern imaging techniques for diagnosis of infection in the era of 18F-fluorodeoxyglucose positron emission tomography

During the past several years, it has become quite evident that positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) imaging can play a major role in the management of patients with suspected infection. Particularly, several groups have demonstrated that this powerful imaging methodology is very effective in the evaluation of osteomyelitis, infected prostheses, fever of unknown origin, and AIDS. In view of its extraordinary sensitivity in detecting disease activity and the ability to quantitate the degree of FDG uptake, PET might prove to be an appropriate modality for monitoring disease activity and evaluating response to therapy. FDG-PET has many advantages over existing imaging techniques for the diagnosis of infectious diseases. These include feasibility of securing diagnostic results within 1.5 to 2 h, excellent spatial resolution, and accurate anatomical localization of sites of abnormality. The availability of PET/computed tomography as a practical tool has further enhanced the role of metabolic imaging in many settings. In the future, this modality is very likely to be employed on a routine basis for detecting, characterizing, and monitoring patients with suspected and proven infection.

Leiomyoma of the adrenal gland presenting as a non-functioning adrenal incidentaloma: case report and review of the literature

A 31-year-old woman was incidentally found to have a large right adrenal mass by computed tomography imaging and underwent a workup that included endocrinological evaluation and positron emission tomography imaging. Laboratory results revealed the mass to be non-functioning. Imaging studies revealed a 9-cm heterogeneous mass that was not FDG avid. Because of concern for adrenal cortical carcinoma, the patient underwent a successful right adrenalectomy. Pathology examination demonstrated an 11-cm circumscribed mass consisting of uniform spindle cells without nuclear pleomorphism, necrosis, or mitotic activity. The diagnosis of leiomyoma was supported by a panel of immunohistochemical stains. Adrenal leiomyomas have been reported in the literature, although most are small and not preoperatively suspicious for malignancy. This case illustrates that benign tumors such as leiomyomas, when large and heterogeneous on imaging, can clinically mimic adrenal cortical carcinomas and should be included in the differential diagnosis of adrenal incidentalomas.