Case report: Chemotherapy plus sintilimab for the treatment of gastroesophageal junction hepatoid adenocarcinoma with liver metastasis: a case study with literature review

Abstract

Objective: To elucidate the clinicopathological features and treatment of metastatic gastroesophageal junction hepatoid adenocarcinoma (GEJ HAC)using a case study and literature review.

Methods: Clinical presentation, results of histology and immunohistochemistry, and next-generation sequencing(NGS) in a patient with GEJ HAC metastasizing to the liver were reviewed. Chemotherapy (SOX or S-1) plus sintilimab was administered.

Results: A 65-year-old male patient with a history of hypertension was admitted to the hospital due to a one-week increase in serum AFP levels. There was a small intraluminal mass at the GEJ and a metastatic lesion in liver segment VIII, as well as enlarged perigastric and retroperitoneal lymph nodes. Tumor cells in both the GEJ and liver tissue exhibited a glandular shape with a nest-like adenoid structure. Immunohistochemical (IHC) analysis of the GEJ tissue showed positivity for AFP, CA19-9, CK7, CK20, MUC-1, P53 (wild type), Glypican-3, and HepPar-1, and negativity for Arginase-1, CD10, and Her-2. In the metastatic liver tissue, IHC testing demonstrated positivity for AFP, CD10, CK19, CK20, HepPar-1, MUC-1, Ki-67, and P53 (wild type), while CK7 was negative. The NGS report of GEJ mass indicated that the JAK2 and TP53 genes harbored missense mutations, while the MLH1, MSH2, MSH6, PMS2, ERBB2, EGFR, PIK3CA, APC, CTNNB1, CDH1, and DPYD genes were normal. The patient's serum levels of CEA, CA19-9, and AFP were sharply decreased. The patient achieved a major pathological response (MPR) and remains in a progression-free stage.

Conclusions: Sintilimab-based chemotherapy has proven efficacy in achieving a MPR and maintaining a progression-free state for a patient with GEJ HAC that has metastasized to the liver.

Keywords: chemotherapy; gastroesophageal junction; hepatoid adenocarcinoma; liver metastasis; sintilimab.

Figure 1

Imaging findings of CT, MRI, pathology and endoscopy. GEJ mass [(A) 0 month, (H) 6 months, (J) 12 months)], (B–D) liver metastasis and enlarged lymph nodes in CT imaging, (E) liver metastasis in MRI imaging, (F) pathologic findings of GEJ mass (HE staining × 100), (G) pathologic findings of liver metastasis (HE staining × 100), (I) CT scan in 6 months, (K) CT scan in 12 months.

Figure 2

Immunohistochemistry results of mass at GEJ. (A) AFP positive (IHC [EnVision] 100×), (B) Arginase-1 negative (IHC [EnVision] 100×), (C) CA199 positive (IHC [EnVision] 100×), (D) CD10 negative (IHC [EnVision] 100×), (E) CK7 positive (IHC [EnVision] 100×), (F) CK19 positive (IHC [EnVision] 100×), (G) CK20 positive (IHC [EnVision] 100×), (H) Glypican-3 positive (IHC [EnVision] 100×), (I) HepPar-1 positive (IHC [EnVision] 100×), (J) Her-2 negative (IHC [EnVision] 100×), (K) MUC-1 positive (IHC [EnVision] 100×), (L) P53(wild type)positive (IHC [EnVision] 100×).

Figure 3

Immunohistochemistry results of metastatic liver tissue (A) AFP positive (IHC [EnVision] 100×) (B) CD10 positive (IHC [EnVision] 100×) (C) CK7 negative (IHC [EnVision] 100×) (D) CK19 positive (IHC [EnVision] 100×) (E) CK20 positive (IHC [EnVision] 100×) (F) HepPar-1 positive (IHC [EnVision] 100×) (G) MUC-1 positive (IHC [EnVision] 100×) (H) P53 (wild type) positive (IHC [EnVision] 100×) (I) ki67 positive (IHC [EnVision] 100×).

Figure 4

Changes in serum levels of AFP (A), CA 19-9, CEA (B); AFP, alfa-fetoprotein, CEA, carcinoembryonic antigen; CA 19-9, carbohydrate antigen 19-9.

Figure 5

Timeline of the case report. SOX, oxaliplatin and S-1; AFP, alfa-fetoprotein; CEA, carcinoembryonic antigen; CA 19-9, carbohydrate antigen 19-9; MPR, major pathologic response; PFS, progression-free; RECIST, Response Evaluation Criteria in Solid Tumours.