Translate this page into:
Rare Presentation of Metastatic Endometrioid Adenocarcinoma of Uterus Mimicking as Second Primary in Urinary Bladder on 18F-Fluorodeoxyglucose Positron-Emission Tomography/Computed Tomography
Address for correspondence: Dr. Ashwani Sood, Department of Nuclear Medicine, Postgraduate Institute of Medical Education and Research, Chandigarh - 160 012, India. E-mail: sood99@yahoo.com
This is an open access journal, and articles are distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 License, which allows others to remix, tweak, and build upon the work non-commercially, as long as appropriate credit is given and the new creations are licensed under the identical terms.
This article was originally published by Wolters Kluwer - Medknow and was migrated to Scientific Scholar after the change of Publisher.
Abstract
We present a case of endometrioid carcinoma metastasis in the bladder mimicking as the second primary of urinary bladder on 18F-fluorodeoxyglucose positron-emission tomography/computed tomography (18F-FDG PET/CT). The presentations of bladder lesions on 18F-FDG PET/CT are varied, and rare presentations of common malignancies can pose a significant diagnostic challenge as in the index case and highlight the importance of histopathological examination to confirm any unusual FDG uptake confounding the diagnosis.
Keywords
18F-fluorodeoxyglucose positron-emission tomography/computed tomography
endometrioid carcinoma
second primary
urinary bladder
Case Report
A 69-year-old female presented with a 3-month history of painless vaginal bleeding. Initial pelvic ultrasonography revealed hypoechoic lesions (likely fibroids) in the anterior and posterior walls of the body of the uterus and additional lobulated hypoechoic lesions in the left lateral wall of the urinary bladder. A whole-body 18F-fluorodeoxyglucose positron-emission tomography/computed tomography (18F-FDG PET/CT) done for characterization and staging revealed intense tracer uptake in the heterogeneously enhancing soft-tissue lesion in the body and fundus of the uterus [Figure 1a-c]. In addition, there were intensely FDG-avid heterogeneously enhancing soft-tissue lesions in the left posterolateral and posterior wall of the urinary bladder with one of them showing loss of fat planes with the uterine cervix giving the impression of second primary malignancy of urinary bladder with cervical infiltration [Figure 1d and e]. Intense tracer uptake was also noted in few enlarged peripancreatic, mesenteric, precaval, aortocaval, retrocaval, and bilateral external iliac lymph nodes. With a provisional diagnosis of second malignancy in the urinary bladder, the patient underwent transurethral resection of bladder tumor (TURBT). However, histopathology revealed the presence of metastatic endometrioid adenocarcinoma [Figure 2a and b].


Discussion
Endometrial carcinoma is a common malignancy of female genital tract with an increasing incidence in the postmenopausal women.[12] Local recurrence and distant metastases from advanced endometrial carcinoma, even after surgical resection, are known to occur in the pelvis, pelvic and paraaortic lymph nodes, peritoneum, and lungs. Supradiaphragmatic lymph nodes, liver, adrenals, brain, and soft tissues are the uncommon sites for metastases.[3] In advanced cases, it may rarely involve the bladder and bowel mucosa also.[4] Urinary bladder involvement in endometroid carcinoma is a rare entity resulting from direct extension, metastasis, or malignant transformation of endometriosis.[34] This case showcased a diagnostic conundrum of an endometrial neoplasm metastatic to the bladder giving an initial impression of a second primary urothelial malignancy on imaging. 18F-FDG PET/CT is a very sensitive oncological imaging modality with ever-increasing role in genitourinary malignancies. The unusual presentations have been recognized with improved imaging. Few of imaging limitations and pitfalls are encountered, and some of them had been addressed.[567] However, in the index case, subsequent TURBT and histopathological examination revealed the features of nonurological endometroid adenocarcinoma. Thus, this case emphasizes the diagnostic challenges posed by rare presentations of certain malignancies on 18F-FDG PET/CT and the importance of histopathological examination to ascertain the accurate diagnosis and management in such cases.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
References
- Typical and atypical metastatic sites of recurrent endometrial carcinoma. Cancer Imaging. 2013;13:113-22.
- [Google Scholar]
- Endometrioid adenocarcinoma arising from deep infiltrating endometriosis involving the bladder: A case report and review of the literature. Gynecol Oncol Rep. 2015;13:68-70.
- [Google Scholar]
- Utility of early dynamic and delayed post-diuretic 18F-FDG PET/CT SUVmax in predicting tumour grade and T-stage of urinary bladder carcinoma: Results from a prospective single centre study. Br J Radiol. 2017;90:20160787.
- [Google Scholar]
- Dual-modality PET/CT tomography for clinical oncology. Q J Nucl Med. 2002;46:24-34.
- [Google Scholar]
- FDG PET/CT pitfalls in gynecologic and genitourinary oncologic imaging. Radiographics. 2017;37:577-94.
- [Google Scholar]
