Round Ligament Metastatic Gastric Cancer as a Finding in an Inguinal Surgery

CASE REPORT

We report the case of a 54-year-old woman who presented with right inguinal discomfort. An ultrasound suggested an inguinal hernia. An indirect hernia was confirmed, but an unexpected mass depending on a round ligament was found during the surgical procedure. It consisted of a 2.7 × 2 × 1-cm nodule. Biopsy revealed a well-differentiated metastatic adenocarcinoma. Immunohistochemistry showed wide positivity for CK7, CEA, and EMA and negativity for CK20, calretinin, vimentin, TTF1, estrogen, and progesterone receptors. A pancreatobiliary, gastric, or ovarian origin was suggested. Tumor markers were CEA 0.8 (<3.0) and Ca 19.9 443.2 (<30.9). The patient reported a 6-month history of nonspecific symptoms consisting of epigastric discomfort and hunger with no pain and no weight loss. Computed tomography showed gastric wall thickening with abnormal folds and locoregional nodes. A subgastric soft tissue nodule was identified, that corresponded more probably to a pathologic lymph node than to a peritoneal implant. Gastroscopy confirmed a deformed gastric antrum compatible with linitis. The definite pathologic diagnosis of that gastric biopsy confirmed a well-differentiated adenocarcinoma. There were no other metastatic locations.

Chemotherapy with further reevaluation was proposed at the hospital's multidisciplinary cancer conference. The DCF (docetaxel, cisplatin, and 5-fluorouracil) regimen was started.¹ Ca 19.9 normalized after 4 cycles. After 6 cycles, a radiologic partial response was confirmed, as well as continuing Ca 19.9 normalization. A staging laparoscopy was then proposed that revealed an inflammatory aspect of the round ligament, some adhesions over the liver, and a nodule on the anterior abdominal wall. The uterine round ligament was resected. Peritoneal washings were negative. Peritoneal involvement could not be excluded, however, and a radical option was chosen, consisting of subtotal gastrectomy, D2 lymphadenectomy, and hyperthermic intraperitoneal chemotherapy. Intracavitary chemotherapy included cisplatin 50 mg/m² and doxorubicin 15 mg/m². The pathology report showed a well-differentiated intestinal adenocarcinoma in the lesser curvature infiltrating to the subserosa, with changes that may have been due to the treatment (5% of persistent viable tumor). Perineural infiltration, no vascular infiltration, and mesothelial hyperplasia in the epiploa were reported. A 2-cm epiploic nodule with fat necrosis, hemorrhage, and giant cellular reaction was also evaluated. There were no metastases in 13 isolated lymph nodes. There was not any evidence of tumor, either in the round ligament or in the peritoneal samples. Definitive staging was ypT3N0L0V0R0. No other adjuvant treatment was recommended. The patient was free of relapse 30 months after the diagnosis.

DISCUSSION

Tumors presenting within an inguinal hernia are classified as intrasaccular, saccular, or extrasaccular. The current case was extrasaccular. It is, to the best of our knowledge, the only reported case of a metastatic lesion on a round ligament as the first sign of gastric cancer. Rare cases of inguinal hernias as the first presentation of gastric cancer have been reported.^2–4 In gastric cancer, the spread of malignant cells to ovary, perirectal recess, and peritoneum may be seen. The role of gravity in possible drop metastases remains unclear.

Anatomically, the inguinal canal represents a passage arising from the peritoneal cavity, running through the abdominal wall along the spermatic chord in males and the round ligament in females. The vaginalis of the testis is an extension of the peritoneum. We considered peritoneal dissemination as most probable in the present case. The inguinal canal has been identified as an anatomic sanctuary for patients with peritoneal carcinomatosis.⁵ Other peritoneal locations were not confirmed at the diagnosis, because a staging laparoscopy was not done. Initial round ligament involvement was regarded as a drop metastasis. Although the round ligaments are not actually part of the peritoneum, treatment was planned as if for a peritoneal carcinomatosis. The presence of some nodules in the CT scan and the nodules and scars seen in the postneoadjuvant therapy staging laparoscopy supported previous peritoneal involvement.

Some questions arise from this case. Proposing a radical approach for a metastatic gastric tumor would be a debatable option. However, long-term survivals (65 and 89 months) have been reported in some patients with peritoneal carcinomatosis of gastric origin, despite a poor prognosis for most of them (mean survival, 3 months).⁶ Gastric surgery in the metastatic setting could be a good prognostic factor for survival,^7–9 but it could only reflect a selection bias.¹⁰ On the other hand, the use of the controversial hyperthermic intraperitoneal chemotherapy (HIPEC) treatment could be criticized outside of a clinical trial, but clinical trials in such a particular setting—microscopic complete response after 6 cycles of neoadjuvant therapy—are obviously not available. The morbidity and mortality with HIPEC are mainly related to the peritonectomy, which was not thought necessary in this case after the staging laparoscopy, and so hyperthermic chemotherapy was regarded as a low-risk treatment. The best indicator for the use of HIPEC is a low-volume peritoneal carcinomatosis index, as in this case.