case_images: PMC9623255_01
case_images: Ultrasonographic findings of masses in retroperitoneum and abdominal wall. (A) A multicystic mass was found in retroperitoneum of left renal region by grayscale using low-frequency transducer (hollow arrow), which featured multiple septa inside the cystic component (solid arrow). (B) By high-frequency probe, a hypoechoic mass was detected in abdominal wall near the left waist, and there were punctiform and linear blood flow signals in color Doppler (hollow arrow), which featured patchy anechoic areas inside the mass (solid arrow).
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case_images: Ultrasonographic images (Aixplorer US system; SuperSonic Imagine, Aix-en-Provence, France) showed a septal cystic mass of about 8.9 x 4.6 x 5.3 cm with an ill-defined margin, relatively regular shape, and heterogeneous echo in the retroperitoneum of the left renal region by grayscale using a low-frequency transducer (SL 6-1 multifrequency convex transducer) ( Figure 1A ). There were punctiform and linear blood flow signals in the mass in both color Doppler ( Figure 1B ) and power Doppler.
case_images: Contrast-enhanced ultrasound findings of mass in abdominal wall near the left waist (hollow arrow). The hypoechoic mass showed rapid hyperenhancement in arterial phase (solid arrow).
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case_images: Contrast-enhanced ultrasound also showed that the mass in the abdominal wall displayed rapid hyperenhancement in the arterial phase ( Figure 2 ), slightly low enhancement in the venous phase, and low enhancement in the delayed phase, and anechoic areas showed non-enhancement in three phases.
case_images: PET/CT and MRI findings of masses. (A) PET/CT images showed that multiple soft-tissue-density nodules and masses were found in left renal and adrenal region, perisplenic region, left retroperitoneum, left intraabdominal fascia, and left abdominal wall, which featured high uptake of 18F-FDG abnormally. (B) MRI images showed that multiple nodules and masses were found in left renal and adrenal regions, perisplenic region, left retroperitoneum, left vertebral fascia, subcutaneous and muscular layer of left posterior abdominal wall, anterior part of left psoas major muscle, and left iliac fossa, which suggested that the tumor has recurred and metastasized likely.
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case_images: H&E staining results and immunohistochemistry staining results for FH gene and 2SC. (A) H&E staining results showed that the tumor cells in abdominal wall near the left waist, the majority of which were arranged into papillary shape, featured abundant and eosinophilic cytoplasm, round or oval enlarged nuclei with marked eosinophilic nucleoli, and perinucleolar halo (hematoxylin and eosin staining; magnification, x40). (B, C) The tumor cells in abdominal wall near the left waist were visualized by immunohistochemistry staining for FH gene and 2SC, which revealed that the expression of FH protein was lost and 2SC was cytoplasmic positive (magnification, both x100).
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case_images: TTF-1 was negative, and the targeted area was weakly positive with loss of FH gene expression, while the control is positive. The pathological findings were consistent with the metastasis of FH gene-deficient renal cell carcinoma, accounting for about 80% of the tumor ( Figure 4 ).