RESUMEN
BACKGROUND: Primary ovarian mucinous carcinoma is a rare histologic subtype of epithelial ovarian carcinoma and exhibits considerable morphologic overlap with secondary tumour. It is hard to differentiate primary from metastatic ovarian mucinous carcinoma by morphological and immunohistochemical features. Because of the histologic similarity between primary ovarian mucinous carcinoma and metastatic gastrointestinal carcinoma, it has been hypothesized that ovarian mucinous carcinomas might respond better to non-gynecologic regimens. However, the standard treatment of advanced ovarian mucinous carcinoma has not reached a consensus. CASE SUMMARY: A 56-year-old postmenopausal woman presented with repeated pain attacks in the right lower quadrant abdomen, accompanied by diarrhoea, anorexia, and weight loss for about 3 mo. The patient initially misdiagnosed as having gastrointestinal carcinoma because of similar pathological features. Based on the physical examination, tumour markers, imaging tests, and genetic tests, the patient was clinically diagnosed with ovary mucinous adenocarcinoma. Whether gastrointestinal-type chemotherapy or gynecologic chemotherapy was a favourable choice for patients with advanced ovarian mucinous cancer had not been determined. The patient received a chemotherapy regimen based on the histologic characteristics rather than the tumour origin. The patient received nine cycles of FOLFOX and bevacizumab. This was followed by seven cycles of bevacizumab maintenance therapy for 9 mo. Satisfactory therapeutic efficacy was achieved. CONCLUSION: The genetic analysis might be used in the differential diagnosis of primary ovarian mucinous carcinoma and non-gynecologic mucinous carcinoma. Moreover, primary ovarian mucinous carcinoma patients could benefit from gastrointestinal-type chemotherapy.
RESUMEN
Multidrug resistance (MDR) to doxorubicin (DOX) limits its effectiveness against tumor cells. Arsenic trioxide (As2O3) has been reported to reduce MDR in various types of cancer, but the mechanisms involving Ras and p-glycoprotein (P-gp) remain to be fully elucidated. The objectives of the present study were to evaluate As2O3 in reversing MDR to DOX, and to identify the association in antitumor activities between the effectiveness of DOX and Ras/phosphorylated (p) extracellular signalregulated kinase (ERK)1/2 signaling in SGC7901/ADM and SGC7901/S human gastric cancer cell lines. Cytotoxicity and sensitivity towards As2O3 were assessed using nontoxic and mildlytoxic concentrations (0.1 and 0.5 µM, respectively). The reversing effect of As2O3 on MDR was investigated prior to and following treatment with a cytokine activation of the recombinant human granulocyte colony stimulating factor ERK pathway. The SGC7901/ADM and SGC7901/S cells had the same sensitivity to As2O3. The SGC7901/ADM cells were resistant to DOX and As2O3 treatment reduced the level of resistance to DOX (P<0.01). The expression of Pglycoprotein (P-gp) in the SGC7901/ADM cells was higher than in the SGC7901/S cells (P<0.001). As2O3 treatment decreased the levels of Pgp in a time and dosedependent manner (P<0.01). The expression of Ras was higher in the SGC7901/ADM cells than in the SGC7901/S cells, while the expression of pERK1/2 remained the same. As2O3 decreased the levels of Ras and pERK1/2 (P<0.01). Following pretreatment with rhGCSF, the levels of Ras and pERK1/2 were further decreased (P<0.01). Drugresistant gastric cancer cells had higher expression levels of Pgp and Ras, but not of pERK1/2. Non and mildlytoxic doses of As2O3 reduced MDR to DOX through Ras/p-ERK1/2 signaling.