case_images: PMC11010642_01
case_images: Enhanced computed tomography (CT) scan. (A) Before emergent surgery: recurrent and metastatic colon cancer; (B) changes in residual lesions throughout the treatment period. M1, para-iliac vascular mass; M2, rectovesical interstitial mass; C, cycle.
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case_images: Figure 1A ), considered to be recurrence and metastasis of colon cancer. Further colonoscopy revealed a cauliflower-like mass near the transverse colonic anastomosis with a brittle texture, bleeding easily when touched ( Figure 2A ). It showed a right paravalvular iliac mass ( Figure 1B ), a cysto-rectal interstitial mass, and a hydrocele in the right kidney ( Figure 1B ). Pancreatic function ( Figure 5E ), tumor markers ( Figure 5B ), and abdominal CT ( Figure 1B ) were monitored during the treatment procedure.
case_images: (A) Colonoscopy revealed an anastomotic cauliflower-like swelling, that is brittle and bleeds easily on touch. (B) The postoperative specimen showed a tumor 20 * 15 cm in size, of exophytic growth, breaking through the stromal layer, and white in cross-section.
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case_images: Figure 1A ), considered to be recurrence and metastasis of colon cancer. Further colonoscopy revealed a cauliflower-like mass near the transverse colonic anastomosis with a brittle texture, bleeding easily when touched ( Figure 2A ). The postoperative specimen was photographed and revealed a tumor 20 * 15 cm in size, of exophytic growth, breaking through the stromal layer, and white in cross-section ( Figure 2B ).
case_images: Pathological examination results. (A) Hematoxylin-eosin (H&E) staining (*400): low differentiated colonic adenocarcinoma, partly impression cell carcinoma, and partly mucinous adenocarcinoma, accompanied by marked necrosis. (B) PDL-1 test results (*400): >50% of tumor cells were PDL-1 positive. (C) Immunohistochemistry (IHC) staining (*400): CDX-2, +; CK7, -; CK8/18, +; Her-2 (0); Ki67 positive cells (70%); MLH1, +; MSH6, +; PMS2, +; Syn, -; CK20, +; and MSH2, +.
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case_images: H&E staining showed poorly differentiated adenocarcinoma, partly impression cell carcinoma, and partly mucinous adenocarcinoma, accompanied by marked necrosis ( Figure 3A ). Figure 3C ). Postoperative anti-infection, adequate drainage, and nutritional support were given; however, an anastomotic fistula appeared 4 days after surgery. Further jejunostomy was performed resulting in the healing of the anastomotic fistula. Figure 3B ). Furthermore, the patient's BMI, 16 kg/m2; ECOG, 1 point; KPS, 90 points; and NRS, 0 point.
case_images: Flow cytometry results. (A) Peripheral blood immunization evaluation results: depressed immune function. (B) Peripheral blood PD-1 test revealed PD-1+CD8+-positive and CD3-CD19-CD14+CD16-HLA-DR-positive cells.
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case_images: Peripheral blood immunization evaluation revealed depressed immune function ( Figure 4A ). The peripheral blood PD-1 test showed that PD-1+CD8+ and CD3-CD19-CD14+CD16-HLA-DR were positive ( Figure 4B ).
case_images: Blood examination results. (A) Blood routine results. Reference range: PLT 125-350 * 109/L, HB 130-175 g/L, WBC 3.5-9.5 * 109/L, and RBC 4.3-5.8 * 1012/L. (B) Tumor marker results. Reference range: AFP 0-7 ng/ml, CEA 0-3.4 ng/ml, CA125 0-35 U/ml, and CA19-9 0-27 U/ml. (C) Liver function results. Reference range: ALT 9-50 U/L, AST 15-40 U/L, TBIL <26 mumol/L, gamma-GGT 10-60 U/L, and ALB 40-55 g/L. (D) Renal function results. Reference range: urea 3.1-8 mmol/L, Crea (creatinine) 57-97 mumol/L, and UA (uric acid) 208-428 mumol/L. (E) Pancreatic function results. Reference range: AMY 0-640 U/L. (F) Thyroid function results. Reference range: FT4 10.44-24.38 pmol/L, FT3 2.77-6.31 pmol/L, and TSH 0.380-4.340 muIU/ml.
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case_images: Blood routine results ( Figure 5A ), impaired liver function ( Figure 5C ), and hyperthyroidism ( Figure 5F ) were manageable. Pancreatic function ( Figure 5E ), tumor markers ( Figure 5B ), and abdominal CT ( Figure 1B ) were monitored during the treatment procedure. Regarding the process of disappearance of the lesion, the right paravalvular iliac mass did not shrink in four cycles of medication and resulted in ureteral obstruction, hydronephrosis, and renal hypoplasia ( Figure 5D ).
case_images: The patient's timeline.
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case_images: The patient's timeline is shown in  Figure 6 .