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Incidental Finding of Acute Appendicitis on FDG PET/CT in Breast Carcinoma
Address for correspondence: Dr. Madhavi Tripathi, Department of Nuclear Medicine, AIIMS, New Delhi, India. E-mail: madhavi.dave.97@gmail.com
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Received: ,
Accepted: ,
This article was originally published by Wolters Kluwer - Medknow and was migrated to Scientific Scholar after the change of Publisher.
Abstract
The interpretation of F-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) scans can be confounded by incidental findings, as illustrated in this case of a 47-year-old woman with a history of breast carcinoma. Following neoadjuvant chemotherapy and mastectomy, she underwent FDG PET/CT for disease evaluation, revealing unexpected hypermetabolic activity in the right iliac fossa corresponding to acute appendicitis. Thus, FDG PET/CT has the potential to uncover treatable conditions beyond cancer and imaging findings need clinical correlation.
Keywords
Appendicitis
florodeoxyglucose positron emission tomography/computed tomography
inflammation
Image Legend
A 47-year-old woman with left breast carcinoma was referred to us for fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT). She had undergone modified radical mastectomy following neoadjuvant chemotherapy, revealing invasive breast carcinoma (nonspecific type, Grade III) with metastatic involvement of all 17 dissected lymph nodes. Immunohistochemistry demonstrated Her2 neu positivity, leading to 17 cycles of trastuzumab therapy subsequently. Findings revealed metabolically active cutaneous and subcutaneous thickening in the left anterior chest wall with left cervical, left axillary, and left internal mammary lymph nodes suggestive of residual disease [Figure 1a and b]. A tubular-shaped increased FDG uptake was also noted in the right iliac fossa, corresponding to the appendix on CT [Figure 1c] with thickened walls and adjacent peri-cecal lymph nodes [Figure 1d].
On further inquiry, the patient revealed intermittent abdominal pain, which worsened after the scan was done, with rebound tenderness in the right iliac region on palpation. Laboratory tests indicated leukocytosis. Follow-up abdominal ultrasonography confirmed thickened appendiceal walls measuring 5 mm in thickness and 9.8 mm in diameter, accompanied by subcentimetric lymph nodes and minimal fluid, indicative of uncomplicated acute appendicitis [Figure 2a and b]. Surgical intervention was subsequently planned [Figure 3].
An inflamed appendix may show increased FDG uptake and CT scan usually shows increased appendiceal caliber with peri-appendiceal haziness, thickening of the lateral conal fascia, adjacent free fluid, enlarged lymph nodes, and appendicolith.[1] A few case reports have described similar findings.[234] Metastasis to the appendix in breast carcinoma is also not uncommon.[56] Hence, FDG accumulation in the right pelvic fossa warrants careful interpretation to avoid misdiagnosing metastatic disease although FDG PET/CT is not indicated for evaluating acute appendicitis, yet, it may be an incidental finding during the workup of malignant diseases. It is essential to undertake a comprehensive clinical history and examination to discern these confounders, as exemplified by the demonstrated case.
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.
Conflicts of interest
There are no conflicts of interest.
None.
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