Shinkyo Yoon

Cross-Sectional Study of Imatinib Plasma Trough Levels in Patients With Advanced Gastrointestinal Stromal Tumors: Impact of Gastrointestinal Resection on Exposure to Imatinib

PURPOSE Imatinib plasma trough levels (C(min)) have been reported to correlate with treatment outcomes in patients with gastrointestinal stromal tumors (GISTs). We therefore have evaluated the correlation between imatinib C(min) and the clinical characteristics of patients with GIST. PATIENTS AND METHODS Steady-state imatinib C(min) in 107 patients with GIST who were taking imatinib 300 to 800 mg/d was measured. RESULTS In patients treated with imatinib 400 (n = 92), 300 (n = 7), 600 (n = 2), or 800 (n = 11) mg/d, imatinib C(min) was 1,305 +/- 633 ng/mL, 1,452 +/- 830 ng/mL, 1,698 +/- 725 ng/mL, and 3,330 +/- 1,592 ng/mL, respectively. Of the 92 patients treated with 400 mg/d imatinib, 59 patients (63%) were men; the median age was 55 years (range, 28 to 76 years), and the median duration of imatinib use before sampling was 8.8 months (range, 0.5 to 67.6 months). The mean inter- and intrapatient variability rates were 44.7% and 26.5%, respectively. In univariate analyses, high C(min) was correlated with advanced age (P = .02), low creatinine clearance (P = .001), low hemoglobin (P = .03), and low albumin (P < .001) concentrations. Imatinib C(min) was also significantly lower in patients with (n = 18; 942 +/- 330 ng/mL) than without (n = 74; 1,393 +/- 659 ng/mL) major (ie, total or subtotal) gastrectomy (P = .002). In multivariate analysis, albumin (P = .001) concentrations, creatinine clearance (P = .002), and major gastrectomy (P = .003) were significantly correlated with C(min). CONCLUSION In patients with GIST, imatinib C(min) at steady state was significantly associated with albumin concentration, creatinine clearance, and previous major gastrectomy. Although its clinical impact is unclear at present time, monitoring of imatinib C(min) might be particularly important for optimal treatment with imatinib in patients who have undergone major gastrectomy.

Angiosarcoma of the Retroperitoneum: Report on a Patient Treated with Sunitinib

A 52 year-old woman presented with an incidentally detected retroperitoneal angiosarcoma and multiple hepatic metastases. After chemotherapy with weekly paclitaxel and doxorubicin, angiosarcoma had progressed rapidly. Because few chemotherapeutic options were available for her, sunitinib (37.5 mg/day, daily) as a salvage regimen was administered. Although sunitinib was interrupted after two weeks due to hematologic abnormalities, some metastatic nodules were regressed. Therefore, sunitinib was recommenced at a reduced dose (25 mg/day, daily). Serial computed tomography scans showed variable response in each tumor, however, sunitinib at least delayed tumor progression, compared to previous chemotherapy. With this case report, we suggest sunitinib may be effective against angiosarcomas. When sunitinib is administered to patients with angiosarcomas, hematologic abnormalities should be monitored frequently as severe hematologic toxicity may be caused either by sunitinib per se or angiosarcoma.

Clinical Implication of Serine Metabolism-Associated Enzymes in Colon Cancer.

Purpose: Recently, enzymes of the serine synthetic pathway (SSP) have been suggested as key player in the metabolic adaptation of oncogenesis. We assessed the expression of enzymes of the SSP in colonic tumor tissue (TT) and paired normal tissue (pNT) and the prognostic implications. Methods: From 2006 to 2010, we included 486 patients with colon cancer who underwent curative surgery at Kyungpook National University Hospital. Phosphoglycerate dehydrogenase (PHGDH), pyruvate dehydrogenase kinase (PDK) 1, PDK2, pyruvate kinase M2 (PKM2), and phosphoserine aminotransferase (PSAT) expression were investigated by immunohistochemical staining (IHC) in TT and pNT. The IHC values were calculated by multiplying intensity by proportion. The final score was classified as follows: 0-2 as negative and 3-12 as positive. Results: During the median follow-up duration of 55.5 months (37.4-90.6), 78 patients experienced recurrence. The expression of PHGDH, PDK1, and PSAT was significantly higher in TT than pNT (p < 0.001 for each). The univariate analysis for relapse-free survival revealed that TT PDK2 positivity was the only positive prognostic factor (p = 0.023). However, the expression of TT PDK2 did not represent a prognostic value in multivariate analysis. Conclusions: In conclusion, PHGDH, PDK1, and PSAT were significantly increased in colonic TT compared with pNT. The prognostic implication of these enzymes needs to be further investigated.

Pneumatosis Intestinalis After Cetuximab-containing Chemotherapy for Colorectal Cancer

Cetuximab, a chimeric monoclonal antibody to epidermal growth factor receptor, is an effective chemotherapeutic agent for patients with metastatic colorectal cancer. Whereas several specific adverse reactions to cetuximab such as skin rash and nail toxicity have been reported, there have been few reports of pneumatosis intestinalis related to cetuximab-containing chemotherapy. We describe here three patients with colorectal cancer who developed pneumatosis intestinalis during treatment with cetuximab-containing chemotherapy, which developed after 7, 19 and 47 weeks of cetuximab treatment, and discovered on routine follow-up computed tomographic scans for response evaluations. None of these patients complained of abdominal pain, showed signs of peritoneal irritation on physical examination or had elevated serum concentrations of acute inflammatory markers. Following cessation of cetuximab and conservative medical treatment, all three patients showed complete resolution of pneumatosis intestinalis on abdominal pelvic computed tomographic scans.

Prognostic impact of β2-microglobulin in patients with non-gastric mucosa-associated lymphoid tissue lymphoma

Abstract Although serum β2-microglobulin (B2M) has been suggested as a prognostic factor for several hematologic malignancies, it has not been comprehensively investigated in non-gastric mucosa-associated lymphoid tissue (MALT) lymphoma. Between January 2000 and May 2013, a total of 174 patients with non-gastric MALT lymphoma were identified from a prospectively developed database. Baseline serum B2M was elevated in 17 (10%) patients. In univariate analysis, serum B2M ≥ 2.5 mg/L was significantly associated with progression-free survival (PFS, p < 0.001) and overall survival (OS, p < 0.001). Multivariate analysis identified serum B2M as an independent prognostic factor in PFS (hazard ratio [HR] = 3.5, 95% confidence interval [CI]: 1.2–10.0; p = 0.02) and OS (HR = 26.9, 95% CI: 2.7–269.7; p = 0.005), after adjustment for IPI and treatment modalities. Baseline serum B2M is an independent prognostic factor in patients with non-gastric MALT lymphoma.

Imatinib Plasma Monitoring-Guided Dose Modification for Managing Imatinib-Related Toxicities in Gastrointestinal Stromal Tumor Patients

Imatinib, the first-line treatment in patients with advanced gastrointestinal stromal tumors (GIST), is generally well tolerated, although some patients have difficulty tolerating the standard dose of 400 mg/day. Adjusting imatinib dosage by plasma level monitoring may facilitate management of patients who experience intolerable toxicities due to overexposure to the drug. We present two cases of advanced GIST patients in whom we managed imatinib-related toxicities through dose modifications guided by imatinib plasma level monitoring. Imatinib blood level testing may be a promising approach for fine-tuning imatinib dosage for better tolerability and optimal clinical outcomes in patients with advanced GIST.

Prognostic Significance of the Number of Metastatic pN2 Lymph Nodes in Stage IIIA-N2 Non–Small-Cell Lung Cancer After Curative Resection

UNLABELLED Stage IIIA-N2 non-small cell lung cancer (NSCLC) shows prognostic heterogeneity. We investigated the prognostic relevance of the number of metastatic pN2 nodes in patients with IIIA-N2 NSCLC. The criteria for the number of pN2 used in this study were significantly associated with the survival outcomes after surgery and may improve the accuracy of prognostic prediction in this subgroup of patients. INTRODUCTION There have been controversies regarding the prognostic relevance of the number of positive N2 nodes in pathologic stage IIIA-N2 non-small-cell lung cancer (NSCLC). We examine prognosis of patients with pathologic stage IIIA-N2 with classifying the number of positive N2 nodes into subgroups. METHODS From January 1997 to December 2004, 250 patients were diagnosed with pathologic stage IIIA-N2 disease. All patients underwent mediastinal lymph node dissection. After excluding 44 patients with preoperative chemotherapy, incomplete resection, and postsurgical mortality, 206 patients were included in the analysis. Patients were classified according to the number of positive N2 lymph nodes (N2a: 1 [n = 83], N2b: 2-4 [n = 82], N2c: ≥ 5 [n = 41]), and its correlation with survival outcomes were investigated. RESULTS With a median follow-up of 96.3 months, 5-year disease-free survival (DFS) was 27.2% (95% confidence interval [CI], 21.6-33.7), and 5-year overall survival (OS) was 37.7% (95% CI, 31.5-44.7) in all patients. The number of metastatic N2 lymph nodes was associated with DFS (P < .001) and OS (P = .01). In the N2a, N2b, and N2c groups, 5-year DFS rates were 38%, 24%, and 5%, respectively, and 5-year OS rates were 47%, 35%, and 24%, respectively. In a multivariate analysis, the number of metastatic N2 lymph nodes was an independent prognostic factor for DFS and OS. CONCLUSION Stratification of patients according to the number of metastatic N2 lymph nodes may improve the accuracy of prognostic prediction among patients with curatively resected stage IIIA-N2 NSCLC.

Abdominal cavernous Iymphangiomas: CT findings

Two adult patients with histopathologically proved cavernous lymphangiomas and one adult patient with lymphangiomas of strongly presumed cavernous type by cytologic and computed tomographic findings are reported. On computed tomograms, multiple, aggregated, small, and tiny cysts without a solid portion, along the lymphatic channels are characteristic computed tomographic findings for cavernous lymphangiomas.

Prognostic significance of serum beta-2 microglobulin in patients with diffuse large B-cell lymphoma in the rituximab era

The prognostic value of serum beta-2 microglobulin for diffuse large B-cell lymphoma (DLBCL) is not well known in the rituximab era. A retrospective registry data analysis of 833 patients with de novo DLBCL treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) was conducted to establish the prognostic significance of serum beta-2 microglobulin at a ≥2.5 mg/L cutoff. Five-year progression-free survival (PFS, 76.1% vs. 41.0%; p < 0.001) and overall survival (OS, 83.8% vs. 49.2%; p < 0.001) were significantly worse in patients with elevated serum beta-2 microglobulin (n = 290, 34.8%). Furthermore, the five parameters of the International Prognostic Index, accompanying B symptoms, bone marrow involvement and impaired renal function were associated with worse PFS and OS. In multivariate analysis, elevated beta-2 microglobulin was a significant poor prognostic factor for PFS (hazard ratio [HR], 1.70; 95% confidence interval [CI], 1.29–2.24; p < 0.001) and OS (HR, 2.0; 95% CI, 1.47–2.75; p < 0.001). In an independent validation cohort of 258 R-CHOP treated patients with de novo DLBCL, elevated beta-2 microglobulin levels remained a significant poor prognostic factor for PFS (HR, 2.03; 95% CI, 1.23–3.32; p = 0.005) and exhibited a strong trend of association with worse OS (HR, 1.64; 95% CI, 0.98–2.75; p = 0.062). The significance of serum beta-2 microglobulin levels as an independent prognostic factor for patients with DLBCL receiving R-CHOP is confirmed.

Relevance of prognostic index with β2-microglobulin for patients with diffuse large B-cell lymphoma in the rituximab era

Background The International Prognostic Index (IPI) has been a useful tool for predicting the prognosis of aggressive non-Hodgkin lymphoma in the last 20 years. Herein, we aimed to develop a new prognostic model for diffuse large B-cell lymphoma (DLBCL) in the rituximab era. Methods Between March 2004 and June 2012, patients with DLBCL treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone chemotherapy regimen were identified in the database of the Asan Medical Center (AMC) Lymphoma Registry. The primary and secondary endpoints were a new prognostic index for DLBCL and validation of the National Comprehensive Cancer Network-International Prognostic Index in our cohort, respectively. Results The AMC cohort comprised 621 patients. The median follow-up duration was 43.3 months (range, 6.2–122.5 mo). Univariate analysis revealed that age (≤60 vs. >60 yr), lactate dehydrogenase (LDH; within normal vs. increased), Eastern Cooperative Oncology Group performance status (ECOG PS; 0 or 1 vs. ≥2), advanced stage (Ann Arbor stage I/II vs. III/IV), extra-nodal involvement (≤1 vs. >1), B symptoms (no vs. yes), and beta-2 microglobulin (β2MG, ≤2.5 vs. >2.5) can be used to predict overall survival (OS). In multivariate analysis, only age, LDH, ECOG performance status, and β2MG were significantly associated with OS, and we developed a new prognostic model with these 4 factors. The new prognostic model showed better discriminative power compared with the classic IPI. Conclusion Our new prognostic index model for DLBCL in the rituximab era has good discriminative power and is convenient to use.