Abstract
We present a unique case of a heart-shaped lesion identified on Fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) imaging in a patient with metastatic adenocarcinoma of the left lung. The patient, initially diagnosed with a mass in the left upper lobe and a lytic lesion in the L3 vertebra, underwent chemoradiation therapy. Subsequent imaging revealed significant metabolic activity reduction in lung and vertebral lesions. This case emphasizes the occasional atypical and visually intriguing patterns encountered in PET/CT imaging.
Keywords: Fluorodeoxyglucose positron emission tomography/computed tomography, heart-shaped lesion, imaging patterns, lung cancer, metabolic response
A 57-year-old male with a known history of metastatic adenocarcinoma of the left lung presented with persistent cough and expectoration. Initial imaging with computed tomography (CT) revealed a mass in the left upper lobe, enlarged mediastinal lymph nodes, and a lytic lesion in the L3 vertebra. A biopsy from the left lung lesion confirmed the diagnosis of adenocarcinoma with a positive EGFR mutation. The patient underwent chemoradiation therapy, receiving one cycle of carboplatin along with palliative radiotherapy (8 Gy) directed at the L3 lesion. Following this treatment, the patient started on gefitinib therapy at a daily dosage of 250 mg. Due to concerns regarding potential disease progression, the patient was referred for Fluorodeoxyglucose (FDG) positron emission tomography/CT (PET/CT) imaging. The maximum intensity projection (MIP) image [Figure 1] revealed an FDG-avid, typically heart-shaped area in the left upper chest region.
Figure 1.
Maximum intensity projection (MIP) image demonstrates an FDG-avid, heart-shaped focus of uptake in the left upper thoracic region
Further evaluation of the MIP image identified an FDG-avid focus in the midline abdominal region [Figure 2a]. Axial images showed a metabolically active lesion in the left upper lobe with areas of internal calcification on CT [Figure 2b and c], accompanied by significant left pleural effusion and pleural deposits. In addition, there was a FDG avid lesion involving the L3 vertebra with noted soft-tissue components [Figure 2d].
Figure 2.
(a) Maximum intensity projection (MIP) image arrow, (b and c) axial computed tomography and fused images, (d) sagittal fused image arrow, (e) MIP positron emission tomography arrows
The patient subsequently completed four cycles of pemetrexed and carboplatin. Upon response evaluation, PET/CT findings indicated a significant reduction in metabolic activity of both the left lung and the L3 vertebral lesion [Figure 2e]. Overall, these imaging features suggested a partial response to therapy.
This case highlights how a heart-shaped FDG-avid lesion can represent a unique presentation of primary lung adenocarcinoma. Although such appearances are rare, they remind clinicians about how malignancies can manifest in advanced PET/CT studies.[1,2,3] The significant reduction in metabolic activity observed after therapy emphasizes the importance of FDG PET/CT in evaluating treatment response and optimizing patient management. This case illustrates how advanced imaging is essential in guiding clinical decisions for patients with metastatic lung cancer.[4,5,6] Furthermore, this case underscores the dynamic nature of metastatic lung cancer and the utility of FDG PET/CT in monitoring treatment response and disease progression.[7,8,9,10] It emphasizes the need for regular imaging assessments in managing patients with advanced lung cancer, as these assessments provide critical insights into treatment efficacy and inform necessary adjustments in therapeutic strategies.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given his consent for his images and other clinical information to be reported in the journal. The patient understands that his name and initials will not be published and due efforts will be made to conceal his identity, but anonymity cannot be guaranteed.
Conflicts of interest
There are no conflicts of interest.
Funding Statement
Nil.
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