Measurable Krukenberg tumor is preferably characterized as a non-target lesion in the clinical evaluation of gastric cancer therapeutics: A case report

Abstract

Metastatic cystic lesions may be considered as target lesions according to the Response Evaluation Criteria in Solid Tumors (RECIST) 1.1. However, cystic lesions are considered as non-measurable according to RECIST 1.0. Krukenberg tumors are cystic metastases from gastric cancer. The aim of the present case report was to address the question of whether a Krukenberg tumor can be considered as a target lesion. A 30-year-old female patient was diagnosed with stage IV gastric cancer 6 months after parturition. Subsequently, the patient received two courses of oxaliplatin/capecitabine plus trastuzumab (OCT) treatment. The response evaluation was considered as stable disease. However, after four courses of OCT, the cystic target lesion in the right pelvic cavity exhibited an increase in diameter of >40%. After one more cycle of OCT, contrast-enhanced magnetic resonance imaging (MRI) revealed that the diameter of the cystic mass lesion had decreased by >35% and a further two cycles of treatment were administered. After the last OCT cycle, the levels of the tumor markers cancer antigen (CA) 125, CA19-9 and CA153 had markedly increased, although the cystic mass had decreased in size. Eventually, positron emission tomography-computed tomography (PET/CT) was used to assess the efficacy of treatment. A new lesion was identified, indicating progressive disease. The present case demonstrated that the Krukenberg tumor may be considered as a non-target lesion. In addition, tumor markers and PET/CT yielded results complementary to those of contrast-enhanced MRI in the therapeutic assessment of advanced gastric cancer.

Keywords: Krukenberg tumor; Response Evaluation Criteria in Solid Tumors; gastric cancer; target lesion; therapeutic assessment.

Figure 1.

Abdominal and pelvic contrast-enhanced magnetic resonance imaging (MRI) at baseline at the time of diagnosis. (A and B) Contrast-enhanced MRI revealed massive ascites and thickened gastric wall (linitis plastica); (C-F) two cystic lesions located in the pelvic cavity were identified on T2-weighted contrast-enhanced images.

Figure 2.

Abdominal and pelvic contrast-enhanced magnetic resonance imaging (MRI) after two courses of OCT treatment. (A and B) Contrast-enhanced MRI revealed mild ascites and reduced thickness of the gastric wall; (C-F) the cystic lesions are shown on T2-weighted and contrast-enhanced images after two courses of OCT treatment. OCT, oxaliplatin/capecitabine plus trastuzumab.

Figure 3.

Abdominal and pelvic contrast-enhanced magnetic resonance imaging (MRI) after (A and B) four courses and (C and D) five courses of OCT treatment. OCT, oxaliplatin/capecitabine plus trastuzumab.

Figure 4.

Expression levels of tumor markers after OCT therapy, including (A) CEA, (B) CA19-9, (C) CA125 and (D) CA153. OCT, oxaliplatin/capecitabine plus trastuzumab; CEA, carcinoembryonic antigen; CA, cancer antigen.

Figure 5.

Positron emission tomography-computed tomography (PET-CT). A whole-body PET-CT scan revealed fluorodeoxyglucose uptake in the (A) gastric fundus and body, (B) left adrenal gland, (C) mesentery and (D) a right pelvic cystic mass.

Figure 6.

Schematic illustration of the treatment course. CT, computed tomography; MRI, contrast-enhanced magnetic resonance imaging; PET/CT, positron emission tomographycomputed tomography; PR, partial response; SD, stable disease; PD, progressive disease; CAPEOX, capecitabine plus oxaliplatin.