Gastric Cancer with Radiographically Occult Metastatic Disease: Biology, Challenges, and Diagnostic Approaches

Abstract

Gastric adenocarcinoma is an aggressive cancer that demonstrates heterogeneous biology depending on patient ethnicity, tumor location, tumor type, and genetic profile. It remains the third leading cause of cancer deaths worldwide and was estimated to result in 782,000 deaths in 2018. Challenges exist in accurately assessing the disease burden, as available radiological staging often underestimates metastatic disease. This diagnostic handicap, along with the poor understanding of the heterogeneous biology of gastric cancer, has hindered the development of effective therapeutic solutions and thus halted improvement in patient outcomes over the last few decades. The management of occult peritoneal disease is complicated, as most patients are understaged by standard imaging studies and therefore thought to have local diseases. In this article, we systematically review recent literature on the limitations that are associated with standard radiographic staging, discuss recent molecular biology advances to better identify and diagnose occult peritoneal disease, and propose possible management strategies to approach this complicated clinical problem.

Systematic review of diagnostic tools for peritoneal metastasis in gastric cancer-staging laparoscopy and its alternatives

“…Although the location of the primary tumour in the studies included did not show any distinct distribution pattern, most of the lesions arise from non-cardia areas, which corresponds to literature by Rijken et al [ 44 ] and Sanjeevaiah et al [ 46 ] It is frequently reported that signet ring cell or diffuse type tumours have a greater risk of peritoneal metastases but the majority of cases seen in the studies are adenocarcinomas[ 44 , 47 , 48 ]. This may be attributed to the vast majority of gastric cancers being adenocarcinomas or intestinal types[ 49 , 50 ].…”

Lymph Node Involvement in Advanced Gastric Cancer in the Era of Multimodal Treatment—Oncological and Surgical Perspective

“…A German study showed that even 55% of cancerous-infiltrated LN remain smaller than 5 mm [26], which implies high possibility of false-negative and false-positive results. Limitations are related to poor visualisation of nodal engagement [21,27], nodal location dependency and sensitivity rate of 44.4% [22]. Moreover, in up to 30% of negative CT scans, endoscopic ultrasound (EUS) reveals nodal involvement [27,28].…”

“…Limitations are related to poor visualisation of nodal engagement [21,27], nodal location dependency and sensitivity rate of 44.4% [22]. Moreover, in up to 30% of negative CT scans, endoscopic ultrasound (EUS) reveals nodal involvement [27,28]. Another restriction is associated with ambiguous restaging before potential gastrectomy.…”