Surgical treatment for late-appearing adrenal metastasis from gastric cancer: report of two cases

A 51-year-old man visited our hospital for a regular postoperative follow-up examination for gastric cancer in April 2012. He had undergone a total gastrectomy for AGC on the cardia in September 2006 (pT2bN1M0, stage II, according to the classification system set forth in the sixth edition of The TNM Classification of Malignant Tumours by the International Union against Cancer (UICC)[6]). At that time, the histological examination revealed a poorly differentiated tubular adenocarcinoma that had infiltrated the subserosal layer. Thirty-five lymph nodes were retrieved, and one was metastatic. After an R0 resection, the patient received six cycles of cisplatin and 5-fluorouracil (5-FU) combination chemotherapy until March 2007. He was followed up regularly with tumor markers, abdominal computed tomography (CT) scans and positron emission tomography (PET)-CT every 6 months for 2 years and then annually thereafter.

The patient had no symptoms or abnormal findings suggesting recurrence until 5 years postoperatively, in September 2011. An abdominal CT scan showed an isolated left adrenal mass, 3 cm in size, with inhomogeneous enhancement, which was suspected to be a relapse of the disease or an adrenal incidentaloma (Figure 1A). He was recommended for a follow-up examination because tumor markers were within normal limits and there was only minimal fluorodeoxyglucose (FDG) uptake visible on the PET scan (Figure 1B). Six months later a CT scan showed that the preexisting adrenal mass had increased in size (up to 6 cm), and PET-CT scans showed a more definite hypermetabolic focus (Figure 2). A CT-guided biopsy of the tumor was performed for histological confirmation, which revealed a poorly differentiated adenocarcinoma compatible with metastasis from gastric cancer (Figure 3A). Following sufficient exploration for surgical resection and other alternative treatments, surgical resection was planned with the patient’s informed consent.

In the patient’s second operation, 6 years after initial operation, the left adrenal tumor was found to have extended to the adjacent organs: to the distal pancreas anteriorly, to the renal capsule inferiorly and to the diaphragm superiorly. An en bloc resection, including the left adrenal gland, kidney, a portion of the diaphragm, distal pancreas and spleen, was performed (Figure 3B). Histopathological examination revealed a poorly differentiated metastatic adenocarcinoma invading the renal capsule and distal pancreas. Other than the main tumor, we detected three metastatic lymph nodes among a total of eight retrieved lymph nodes in the paraaortic region. The patient’s postoperative course was uneventful, and he was discharged on postoperative day 13. He subsequently received eight cycles of second-line chemotherapy with 120 mg/day S-1 (TS-1; Taiho Pharmaceutical, Tokyo, Japan). During the 13-month follow-up period, there was no evidence of cancer recurrence based on CT findings and tumor markers.

A 45-year-old woman underwent distal gastrectomy for AGC at our hospital in July 2006 (pT2bN0M0, stage IB, according to the UICC classification system[6]). A histological examination of the primary gastric cancer lesion revealed a signet ring cell carcinoma that had infiltrated the subserosal layer. There was no lymph node metastasis in any of the 44 retrieved nodes, and the proximal resected margin was 2.0 cm. The patient remained well until 1 year after surgery, when recurrent remnant gastric cancer invading the distal pancreas was detected during a follow-up evaluation. After no other metastasis was identified, a complete, total gastrectomy with distal pancreaticosplenectomy was performed in July 2007. Postoperative adjuvant combination chemotherapy included six cycles of 5-FU and cisplatin. She remained well for 2 years following her second operation until she experienced mild swallowing difficulty. A CT scan and barium swallowing series showed a recurrent mass around the jejunojejunostomy site that compressed the Roux limb and resulted in a luminal obstruction. A third operation was performed in July 2009. En bloc resection of the recurrent tumor, including the Roux limb, was carried out, and a repeat esophagojejunostomy with jejunojejunostomy was performed. She refused postoperative adjuvant chemotherapy and remained well for 3 years. However, a 3-cm left adrenal mass found on a CT scan showed intense FDG uptake on PET-CT scans (Figure 4). In this patient, sufficient clinical information was available for surgical resection and other alternative treatments, so surgical resection was planned with the patient’s informed consent. A fourth operation was performed in May 2012, including a left nephroadrenalelctomy, transverse colectomy and resection of the Roux limb because of direct invasion of the adrenal tumor into the renal capsule and adjacent jejunal mesentery and mesocolon (Figure 5A). A histopathological examination revealed a 6 × 3–cm adrenal tumor with metastatic signet ring cell carcinoma, which is the same histologic finding as that of primary and recurrent lesions (Figure 5B). The regional lymph nodes, including jejunal mesentery (0 of 13), transverse mesocolon (0 of 1) and renal parenchyma were free from metastasis or direct tumor invasion. The patient’s postoperative course was uneventful, and she was discharged on postoperative day 10 without any complications. She received second-line chemotherapy with seven cycles of 100 mg/day S-1. During the 12-month follow-up period, no definite evidence of tumor recurrence was found.