case_images: PMC11260700_01
case_images: Histological findings and BRAF K601E sequence data. (A) Hematoxylin-eosin staining of the primary tumor sample (20x). (B-D) The primary tumor sample was negative for TTF-1 expression but positive for p40 and p16 expression (all shown at 20x). (E) Next-generation sequencing data illustrating the BRAF K601E mutation, visualized using the Integrative Genomics Viewer (IGV).
case_images: fonc-14-1374594-g001.jpg
case_images: PMC11260700_01_fonc-14-1374594-g001.jpg
case_images: f1
case_images: Biopsy of the skin lesions of the precordium revealed poorly differentiated carcinoma ( Figure 1A ), with negative immunostaining for TTF-1 and positive immunostaining for p40 and p16 ( Figures 1B-D ). However, due to worsening pain from the growth of cutaneous metastases and deterioration of performance status, this treatment was discontinued after two courses ( Supplementary Figure 1A, B ). Genomic testing (Oncomine Dx Target Test Multi-CDx system ) of precordium skin metastasis (70% tumor cell content) revealed a mutation of BRAF K601E with a variant allele frequency of 17.4% ( Figure 1E ). One month later, significant tumor reduction was observed ( Figure 2 ), but by 1.5 months, several cutaneous metastases, including the precordium lesion, had enlarged, indicating limited treatment efficacy ( Supplementary Figures 1C ,  2 ).
case_images: Tumor shrinkage after dabrafenib and trametinib. (A) Image of the primary tumor located in the left upper lobe of the lung before combination therapy. (B) The primary tumor almost disappeared one month after combination therapy. (C) Lymph node metastasis in the left neck before combination therapy. (D) Left neck lymph node metastasis decreased one month after combination therapy. (E) The appearance of the precordium cutaneous metastasis before combination therapy. (F) Precordium cutaneous metastasis shrank one month after combination therapy.
case_images: fonc-14-1374594-g002.jpg
case_images: PMC11260700_01_fonc-14-1374594-g002.jpg
case_images: f2
case_images: One month later, significant tumor reduction was observed ( Figure 2 ), but by 1.5 months, several cutaneous metastases, including the precordium lesion, had enlarged, indicating limited treatment efficacy ( Supplementary Figures 1C ,  2 ).