PMC7342492_01
PET-CT showed multiple osteolytic bone destruction with increased metabolism, pathological fracture of the right third rib (A); eczema-like changes in the skin of the scrotum at the root of the penis (B); the epidermis was eroded partly, and scattered, nested Paget's cells could be observed in the spinous layer with the dermal inflammatory cells infiltrated (C).
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PET-CT showed multiple osteolytic bone destruction with increased metabolism, pathological fracture of the right third rib (Figure 1A). Eczema-like change in the skin of the scrotum at the base of the penis was observed, with a size of 2.0x1.5 cm (Figure 1B). Then, the scrotal skin lesion biopsy was performed and pathological examination showed primary EMPD with Paget's cells in the spinous layer (Figure 1C).
Next-generation sequencing (NGS) showed HER2 R678Q in exon 17, S310Y in exon 8 and S310F in exon 8; triple HER2 mutations could be observed in tissue and ctDNA.
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The next-generation sequencing assay showed that this patient had triple uncommon HER2 mutation, namely HER2 R678Q in exon 17, S310Y in exon 8 and S310F in exon 8 (Figure 2).
Computed tomography showed enlarged lymph nodes in the right groin area was shortened after pyrotinib treatment (A) before pyrotinib treatment and after (B) 2 months, (C) 3 months; hemoglobin and platelets counts were increased and CEA concentration was decreased.
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After pyrotinib treatment, the general pain and discomfort symptoms were significantly relieved, platelets and hemoglobin were increased (Figure 3). According to the response evaluation criteria in solid tumor (version 1.1), the patient was considered to have a partial response to pyrotinib (Figure 3). The last CT scan showed that the right inguinal lymph node was stable (Figure 3).