A 74-year-old man was referred to our hospital for the examination of diarrhea and hematochezia lasting for 3 months. A colonoscopy revealed a circumferential advanced type 2 rectal cancer at 7 cm from the anal verge (Fig. 1a). The colonoscope managed to pass through the tumor, but the tumor made the rectal lumen so narrow that it could safely be assumed that the rectum would be obstructed within a few months. The pathological result of the biopsy was moderately differentiated adenocarcinoma. A contrast-enhanced computed tomography scan (CE-CT) showed clearly enhanced rectal lesion in the upper rectum (Ra) with no lymphadenopathy or distant metastasis (cT3N0M0, cStage IIa, Japanese Society for Cancer of the Colon and Rectum (JSCCR), 3rd edition [1]; cT3N0M0, cStage IIA, Union for International Cancer Control (UICC), 8th edition [2]) (Fig. 2a).
CE-CT also revealed a poorly enhanced tumor 26 mm in size in the pancreatic head (Fig. 2b). Pancreatic cancer that invaded the anterior membrane was suspected. The tumor widely abutted the superior mesenteric vein (Fig. 2c), implying that the tumor was borderline resectable [3]. No lymphadenopathy or distant metastasis was detected by CE-CT (cT3N0M0, cStage IIA, Japan Pancreas Society (JPS), 4th edition [4]; cT3N0M0, cStage IIA, UICC 8th [2]).
An esophagogastroduodenoscopy (EGD) was performed to assess malignancy in the upper gastric tract, revealing the presence of type II esophageal carcinoma 36–39 cm from the front teeth possibly with muscularis propria invasion (Fig. 1b). No lymphadenopathy or distant metastasis was detected by CE-CT (cT2N0M0, cStage II, Japan Esophageal Society (JES), 11th edition [5]; cT2N0M0, cStage II, UICC 8th [2]). The pathological diagnosis of the biopsied specimen was squamous cell carcinoma.
The clinical diagnosis was simultaneous advanced triple cancer involving esophageal and pancreatic cancer, and rectal carcinoma. Each tumor was surgically resectable, but the simultaneous resection of the three tumors was likely to cause too much stress. Although pancreatic cancer was the prognostic determinant for the patient, rectal obstruction had to be prevented to initiate treatment for pancreatic cancer. Therefore, we chose the rectal cancer as our first target of treatment. The outline of the whole course of treatment is described in Fig. 3. We performed a laparoscopic Hartmann’s operation to minimize the likelihood of postoperative complications. The operation time was 424 min, and the blood loss was minimal. The pathological result was moderately differentiated adenocarcinoma, Ra, pT3N0M0, pStage IIa (JSCCR 3rd [1]); pT3N0M0, pStage IIA (UICC 8th [2]), R0 resection (Fig. 4a). The postoperative clinical course was remarkable for a portal vein thrombus (PVT) detected by CE-CT, which was performed on the 5th day after surgery to evaluate abnormally elevated liver enzymes. Oral edoxaban at 30 mg/day was initiated, after which the levels of liver enzymes gradually improved. The patient was discharged on the 19th day after surgery.
The pancreatic tumor was our next target because the prognostic determinant for this patient was assumed to be pancreatic cancer rather than esophageal cancer. The borderline resectability of the tumor and the possibility of PVT being a tumor embolism led us to the initiation of neoadjuvant chemotherapy (NAC) for pancreatic cancer. The regimen of gemcitabine plus nab-paclitaxel was started with the expectation of its being effective for both esophageal and pancreatic cancer, and it was administered for 10 courses. The duration of NAC was prolonged due to the patient’s preference. After NAC, PVT disappeared, and the main tumor shrank from 26 to 18 mm in diameter (Fig. 5a). No lymphadenopathy or distant metastasis appeared on a follow-up CE-CT. An EGD was also performed to assess to what extent NAC, which was performed for treatment of pancreatic cancer, was effective for the treatment of esophageal cancer. Esophageal cancer showed regression in terms of its invasion into the muscularis mucosae (ycT1aN0M0, ycStage 0, JES 11th [5]; ycT1aN0M0, ycStage I, UICC 8th [2]) (Fig. 5b). The clinical effect of NAC on the pancreatic and esophageal cancers resulted in partial response and stable disease based on the RECIST classification version 1.1 [6], respectively. As a result of the preoperative diagnosis of pancreatic cancer (ycT2N0M0, ycStage IB (JPS 4th [4]) and ycT1cN0M0, ycStage IA (UICC 8th [2])), the pancreatoduodenectomy (PD) with portal vein resection and reconstruction was performed. The operation time was 498 min, and the blood loss was 780 ml. The pathological result indicated invasive ductal carcinoma of the pancreas (ypT1cN0M0, pStage IA (JPS 4th [4]) and ypT1cN0M0, ycStage IA (UICC 8th [2])), R0 resection (Fig. 4b). The patient did not develop any complications until discharge on the 24th day after surgery. The patient was administered S-1 as adjuvant chemotherapy for 6 months, which is also commonly used as a part of the chemotherapy regimen for esophageal cancer. S-1 was initiated 26 days after the completion of definitive chemoradiotherapy (CRT) for esophageal cancer.
For the esophageal lesion, we decided to perform CRT, as surgical resection might have been too invasive after the two previous surgeries. Chemotherapy was started with cisplatin plus fluorouracil, and the amount of radiation was 59.4 Gy/33Fr. CRT was continued for 44 days. A follow-up EGD showed the complete disappearance of the tumor. The treatment effect caused a complete response according to the RECIST classification version 1.1 (Fig. 6). The patient is alive with no recurrence nine months after the entire course of treatment.