Polyethylene glycol-based linkers as hydrophilicity reservoir for antibody-drug conjugates

Antibody-drug conjugates (ADCs) are an established therapeutic entity in which potent cytotoxic drugs are conjugated to a monoclonal antibody. In parallel with the great emphasis put on novel site-specific bioconjugation technologies, future advancements in this field also rely on exploring novel linker-drug architectures that improve the efficacy and stability of ADCs. In this context, the use of hydrophilic linkers represents a valid strategy to mask or reduce the inherent hydrophobicity of the most used cytotoxic drugs and positively impact the physical stability and in vivo performance of ADCs. Here, we describe the use of linkers containing monodisperse poly(ethylene glycol) (PEG) moieties for the construction of highly-loaded lysine-conjugated ADCs. The studied ADCs differ in the positioning of PEG (linear or pendant), the bonding type with the antibody (amide or carbamate), and the drug-to-antibody ratio (DAR). These ADCs were first evaluated for their stability in solution under thermal stress, showing that both the drug-linker-polymer design and the nature of the antibody-linker bonding are of great importance for their physical and chemical stability. Amide-coupled ADCs bearing two pendant 12-unit poly(ethylene glycol) chains within the drug-linker structure were the best performing conjugates, distancing themselves from the ADCs obtained with a conventional linear 24-unit PEG oligomer or the linker of Kadcyla®. The pharmacokinetic profiles of amide-linked ADCs, with a linear or pendant configuration of the PEG, were tested in mice in comparison to Kadcyla®. Total antibody pharmacokinetics paralleled the trends in aggregation tendency, with slower clearance rates for the ADCs based on the pendant drug-linker format. The above-mentioned findings have provided important clues on the drug-linker design and revealed that the positioning and configuration of a PEG unit have to be carefully tuned to achieve ADCs with improved stability and pharmacokinetics.

Abstract P4-08-07: PIK3CA mutation, reduced AKT serine 473 phosphorylation, and increased ERα serine 167 phosphorylation are positive prognostic indicators in postmenopausal estrogen receptor-positive, HER2-negative early breast cancer

Background: Endocrine therapy is the most important treatment option for women with estrogen receptor (ER)-positive breast cancer. We recently reported that approximately two-thirds of patients who relapsed within 5 years had received anthracyclins and/or taxanes as adjuvant or neoadjuvant chemotherapy in addition to adjuvant endocrine therapy. New strategies, such as signal transduction inhibitors together with endocrine therapy are required to improve survival. PIK3CA mutations are detected in almost 40% of early ER-positive breast cancers, and are therefore the most frequent genetic alterations in this subtype. PIK3CA mutation status is reported to affect activation of AKT and ERα. Moreover, recent studies demonstrate that patients had a better prognosis when tumors expressed ER, androgen receptor (AR), and vitamin D receptor (VDR).

Methods: Expression of AR and VDR, phosphorylation of AKT serine (Ser) 473 (AKT phospho-Ser473) and ERα Ser167 (ERα phospho-Ser167) were examined by immunohistochemistry in ER-positive, HER2-negative early breast cancer tissues. Seventeen mutations in exons 1, 4, 7, 9, and 20 of the PIK3CA gene were detected in genomic DNA extracted from formalin-fixed paraffin-embedded tumor blocks. Correlations between these biological markers and clinicopathological factors and prognosis were analyzed separately in pre- and postmenopausal women.

Results: Levels of AKT phospho-Ser473 were significantly higher in premenopausal women (n = 62) than in postmenopausal women (n = 152) (P < 0.0001 and P = 0.014, respectively). In contrast, expression levels of AR were significantly higher in postmenopausal women than in premenopausal women (P < 0.0001). In premenopausal women, 26 tumors (43%) had a single mutation of PIK3CA gene, and 3 tumors (5%) had mutations at two sites. In postmenopausal women, 64 tumors (44%) had a single PIK3CA mutation, 6 tumors (4%) had mutations at two sites, and one tumor (1%) had mutations at three sites. In premenopausal women, wild type PIK3CA was associated with smaller tumor size, higher ER expression levels, and lower AR expression levels when compared with women in the same cohort with PIK3CA mutant tumors. In postmenopausal women, patients with PIK3CA wild-type tumors had higher Ki67 labeling index, higher AKT phospho-Ser473, and lower ERα phospho-Ser167 when compared to patients with PIK3CA mutant tumors. Postmenopausal women with PIK3CA wild-type tumors had significantly worse disease-free survival than patients with PIK3CA mutant tumors (P = 0.007). In contrast, PIK3CA mutation status was not correlated with survival in premenopausal women. Low levels of AKT phospho-Ser473 and high levels of ERα phospho-Ser167 were strongly associated with increased disease-free survival in postmenopausal women (P = 0.016 and P = 0.0016, respectively).

Conclusion: ERα activation, in addition to PIK3CA mutation, may be biomarkers for highly endocrine-responsive tumors. This would facilitate the selection of postmenopausal ER-positive breast cancer patients who are likely to benefit from endocrine therapy alone from those who are not.

Citation Format: Ishida N, Hatanaka Y, Baba M, Hagio K, Okada H, Hatanaka KC, Matsuno Y, Yamashita H. PIK3CA mutation, reduced AKT serine 473 phosphorylation, and increased ERα serine 167 phosphorylation are positive prognostic indicators in postmenopausal estrogen receptor-positive, HER2-negative early breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-08-07.

Selective blockade of apoptosis by in vivo electroporation-mediated gene transfer combined with portal infusion of plasmid DNA attenuates liver cirrhosis

AIM

The purpose of the present study was to determine whether in vivo electroporation could achieve selective blockade of apoptosis in a rat liver cirrhosis model.

METHODS

A dimethylnitrosamine (DMN)-induced rat liver cirrhosis model was used. In vivo electroporation was performed after portal vein infusion of plasmid DNA. pFas-Fc plasmid DNA was used to block the apoptotic pathway. pUC/HGF and pCAGGS/EGFP were used as positive and negative controls, respectively. Liver collagen content was evaluated by hydroxyproline assay two weeks after gene transfer. Terminal deoxynucleotidyltransferase dUTP nick end-labeling was simultaneously performed in the liver to evaluate suppression of apoptosis. Survival analysis was performed using 10 rats that received the sFas gene, 10 that received the HGF gene, and 13 that received the GFP gene.

RESULTS

The apoptotic cell index in the DMN-injected liver was significantly lower in rats that received the sFas gene compared with the negative control. The collagen content of the DMN-injected liver was also lower in rats that received the sFas gene compared with the negative control. There was no significant difference in the apoptotic cell index and collagen content of rats that received the sFas and HGF genes. Ten weeks after the initiation of DMN treatment, the survival rates with the sFas, HGF, and GFP genes were 56%, 100%, and 0, respectively.

CONCLUSION

Selective blockade of apoptosis by in vivo electroporation-mediated gene transfer improved the apoptotic cell index, hydroxyproline content, and survival rate. Soluble Fas gene therapy using in vivo electroporation can be a safe and efficient therapy for liver cirrhosis in rats.

Luminal membrane expression of mesothelin is a prominent poor prognostic factor for gastric cancer

Background:

Mesothelin is expressed in various types of malignant tumour, and we recently reported that expression of mesothelin was related to an unfavourable patient outcome in pancreatic ductal adenocarcinoma. In this study, we examined the clinicopathological significance of the mesothelin expression in gastric cancer, especially in terms of its association with the staining pattern.

Methods:

Tissue specimens from 110 gastric cancer patients were immunohistochemically examined. The staining proportion and intensity of mesothelin expression in tumour cells were analysed, and the localisation of mesothelin was classified into luminal membrane and/or cytoplasmic expression.

Results:

Mesothelin was positive in 49 cases, and the incidence of mesothelin expression was correlated with lymph-node metastasis. Furthermore, luminal membrane staining of mesothelin was identified in 16 cases, and the incidence of luminal membrane expression was also correlated with pT factor, pStage, lymphatic permeation, blood vessel permeation, recurrence, and poor patient outcome. Multivariate analysis showed that luminal membrane expression of mesothelin was an independent predictor of overall patient survival.

Conclusion:

We described that the luminal membrane expression of mesothelin was a reliable prognostic factor in gastric cancer, suggesting the functional significance of membrane-localised mesothelin in the aggressive behaviour of gastric cancer cells.

Role of lymph node dissection in the treatment of urothelial carcinoma of the upper urinary tract: multi-institutional relapse analysis and immunohistochemical re-evaluation of negative lymph nodes

AIM

To determine the role of lymph node dissection (LND) in the treatment of urothelial carcinoma (UC) of the upper urinary tract (UUT).

PATIENTS AND METHODS

[Study-1] A retrospective multi-institutional study evaluated 293 patients undergoing predominantly nephroureterectomy for UC of the UUT. Of 293 patients, 267 patients had pure UC and 26 demonstrated other histological components. Regarding the pathological node status, 130 patients had pN0 disease, 141 patients had pNx disease and 22 patients had pN+ disease. The sites of initial recurrence and time to first recurrence were reviewed. The sites of recurrence were classified as locoregional or distant recurrence. The relationship between node status and future recurrence was analyzed. [Study-2] Fifty-one patients treated by nephroureterectomy at Hokkaido University Hospital were included. All had LND and all LNs were negative on hematoxylin and eosin staining. We re-evaluated the presence of micrometastasis in LND specimens by anti-cytokeratin immunohistochemistory.

RESULTS

[Study-1] Of 293 patients, 76 developed disease relapse. Regional lymph node recurrence was the most common site (34 patients). On multivariate analyses that adjusted for the effect of tumor stage and tumor grade, pNx (skipping LND) was an adverse factor not only for locoregional recurrence, but also for distant relapse. [Study-2] Immunohistochemistry identified micrometastases in 7 (14%) of 51 patients. Regarding survival, 5 of these 7 patients with micrometastases were alive at last follow-up.

CONCLUSIONS

On relapse analysis, skipping LND was an adverse factor not only for locoregional recurrence, but also for distant relapse. Immunohistochemistry detected micrometastases in about 14% of patients previously diagnosed as pN0. These findings further support a potential therapeutic benefit of LND by eliminating micrometastases.

DEK oncoprotein regulates transcriptional modifiers and sustains tumor initiation activity in high-grade neuroendocrine carcinoma of the lung

Lung cancer shows diverse histological subtypes. Large-cell neuroendocrine cell carcinoma and small-cell lung carcinoma show similar histological features and clinical behaviors, and can be classified as high-grade neuroendocrine carcinoma (HGNEC) of the lung. Here we elucidated the molecular classification of pulmonary endocrine tumors by copy-number profiling. We compared alterations of copy number with the clinical outcome of HGNEC and identified a chromosomal gain of the DEK oncogene locus (6p22.3) that was significantly associated with poor prognosis. We further confirmed that DEK overexpression was associated with poor prognosis in a larger set of HGNEC. Downregulation of DEK by small hairpin RNA led to a marked reduction of in vitro colony formation, in vivo tumorigenicity and chemo-resistance, and was associated with loss of lung cancer stem cell markers. Gene expression profiling revealed that DEK downregulation was associated with altered expression of transcriptional regulators, which specifically include known targets of interchromosomal translocations in hematopoietic tumors, and knockdown of these epigenetic modifiers affected colony formation activity. Our study showed that DEK overexpression, partly through an increase in its gene dose, mediates the activity of global transcriptional regulators and is associated with tumor initiation activity and poor prognosis in HGNEC.

T cell treatment with small interfering RNA for suppressor of cytokine signaling 3 modulates allergic airway responses in a murine model of asthma

CD4(+) T cells, particularly T helper (Th) 2 cells, play a pivotal role in the pathophysiology of allergic asthma. Suppressor of cytokine signaling (SOCS) proteins control the balance of CD4(+) T cell differentiation. Mice that lack SOCS3 in T cells by crossing SOCS3-floxed mice with Lck-Cre-transgenic mice have reduced allergen-induced eosinophilia in the airways. Here, we studied the effects of SOCS3 silencing with small interfering (si) RNA in primary CD4(+) T cells on Th2 cell differentiation and on asthmatic responses in mice. Th2 cells were generated from ovalbumin (OVA)-specific T cell receptor-transgenic mice in vitro and transferred into recipient mice. Transfection of SOCS3-specific siRNA attenuated Th2 response in vitro. Adoptive transfer of SOCS3-siRNA T cells exhibited markedly suppressed airway hyperresponsiveness and eosinophilia after OVA challenge, with a concomitant decrease in OVA-specific CD4(+) T cell accumulation in the airways. To investigate the mechanism of this impaired CD4(+) T cell accumulation, we inactivated SOCS3 of T cells by crossing SOCS3-floxed (SOCS3(flox/flox)) mice with CD4-Cre transgenic mice. CD4-Cre × SOCS3(flox/flox) mice exhibited fewer IL-4-producing cells and more reduced eosinophil infiltration in bronchoalveolar lavage fluids than control mice in a model of OVA-induced asthma. Expression of CCR3 and CCR4 in CD4(+) T cells was decreased in CD4-Cre × SOCS3(flox/flox) mice. CCR4 expression was also decreased in CD4(+) T cells after transfer of SOCS3 siRNA-treated T cells. These findings suggest that the therapeutic modulation of SOCS3 expression in CD4(+) T cells might be effective in preventing the development of allergic asthma.

The indolent course and high incidence of t(14;18) in primary duodenal follicular lymphoma

BACKGROUND

Information on the clinical behavior of the recently proposed primary duodenal follicular lymphoma (DFL) is limited.

PATIENTS AND METHODS

Demographic data, signs, symptoms, disease stage, and treatment of the patients diagnosed in National Cancer Center Hospital from 1999 to 2007 were collected and analyzed.

RESULTS

Twenty-seven patients were studied. Nineteen patients were asymptomatic at the time of diagnosis. Twenty patients had stage I disease. The histological grade was 1 or 2 in 26 patients. IgH/BCL2 fusion was shown in 20 of the examined 24 cases (83%). Fourteen patients received therapy upon diagnosis (local radiotherapy in 2 patients and chemotherapy in 12 including rituximab therapy), their response rate was 85%, and the estimated progression-free survival (PFS) rate at 3 years was 70%. One patient developed histological transformation. The other 13 patients were followed up; their estimated PFS rate at 3 years was 74%. Five among six cases responded to treatment even after progressive disease. All 27 patients have survived with a median follow-up time of 47.9 months.

CONCLUSIONS

The majority of primary DFL patients have a localized tumor of low-grade histology and are positive for t(14;18). Watchful waiting might be an alternative approach for its indolent course; however, further studies are warranted.

RFA for Small Breast Cancer — What Tumor Can Be Treated Safely?

Breast conserving surgery for small breast cancer has been acceptable as one of standard treatments. However, there are some patients who do not be satisfied with the cosmesis. The aim of this study is to verify the clinical safety and usefulness of the RadioFrequency Ablation (RFA) for small breast cancer without resection. Between January 2006 and Octobar 2007, 20 breast cancer patients were performed RFA with cool-tip RF system after sentinel LN biopsy under general anesthesia. All patients has consented as a clinical research, beforehand. MR mammography was performed after 3 and 6 months of follow-up. All patients were performed postoperative histological examination by 8G-needle mammotome biopsy after 6 months MRI evaluation.Tumor viability after RFA was assessed by hematoxylin -eosin and ssDNA staining. QOL after RFA was assessed both subjectively(QOL-ACD score) and objectively(JBCS cosmesis criterion). Preoperative mammotome revealed 4 patients had DCIS and 16 patients had IDC. The patients median age was 53 years old. The mean greatest dimension of tumors was 1.0 cm (range, 0.5-1.5 cm). MRI showed the dimention of coagulation necrotic area by RFA treatment was 3.5cm (range, 2.5-5.4 cm).All patients have been performed postoperative histlogical examination by 8G mammtome biopsy 6 month after RFA treatment. Coagulation necrosis of the tumor was complete in 20of 20 patients (100%).No patient was troubled skin burn. Neither local and distant recurrence has occurred in all patients (median follow up was 30 month). To treat RFA for breast cancer more safely, we analyzed factors which influenced the size of necrosis. Patient age, body mass index (BMI), background concentration measured by MMG, Fat involvement measured by CT did not influence with the size of nectosis (P=0.21,0.17,0.64,0.40). The state of posterior echo detected by ultrasonography was associated with the size of necrosis (p=0.045). Hence, RFA for the tumor with rich fiber such as scirrhous type tend to make necrosis wider than one with poor fiber such as solid tubular type.Most of patients were satisfied with the cosmesis of the RFA treated breast. Objective QOL score (JBCS cosmesis criterion) showed splendid cosmetic outcome. RFA is one of the effective local treatment for small breast cancer (< 1.5 cm in diameter), and bring breast cancer patients cosmetic satisfaction.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4119.

Prognostic impact of para-aortic lymph node micrometastasis in patients with regional node-positive biliary cancer

BACKGROUND

The presence of para-aortic lymph node metastasis in biliary cancer has a negative impact on prognosis. The relevance of para-aortic lymph node micrometastasis is unknown.

METHODS

A total of 546 para-aortic lymph nodes from 49 patients with biliary cancer with positive regional nodes and negative para-aortic nodes were immunostained with epithelial marker CAM5.2 (specific for cytokeratins 7 and 8). Immunostained tumour foci were classified as micrometastases or isolated tumour cells (ITCs) according to their size (larger or smaller than 0.2 mm).

RESULTS

CAM5.2-positive occult carcinoma cells in para-aortic lymph nodes were detected in nine (18 per cent) of 49 patients and in 18 (3.3 per cent) of 546 para-aortic nodes. There was no difference in postoperative survival between patients with and without CAM5.2-positive para-aortic nodes (P = 0.978), but survival for five patients with micrometastases was significantly worse than that for four patients with only ITCs (P = 0.047).

CONCLUSION

In patients with regional node-positive and para-aortic node-negative biliary cancer, and occult cancer cells in para-aortic lymph nodes, prognosis was significantly worse in those with micrometastases than in patients with only ITCs. An efficient method of intraoperative detection of para-aortic lymph node micrometastases larger than 0.2 mm is needed.

[Three-dimensional demonstration of the spinal cord artery with 64-row computed tomography]

This is a report of 2 cases, in which preoperative 3-dimentional demonstration of the spinal cord artery with 64-row computed tomography was feasible, less invasive, less time-consuming, and helpful in making an interventional strategy for complex aortic disease, resulting in no postoperative paraplegia One was a 63-year-old man, who underwent total arch replacement and a long elephant trunk method for arch and descending aortic aneurysms. The length of the long elephant trunk was so determined that it ended between the descending aortic aneurysm and the origin of the spinal cord artery. The second case was a 59-year-old man, who underwent descending thoracic aorta replacement for type B aortic dissection. During the distal anastomosis, the dissection septa were trimmed in order to perfuse the blood into the true and 2 false channels, one of which was connected to the spinal cord artery. In this report, we are not suggesting that preservation of the demonstrated spinal cord artery is enough for spinal cord protection, because it is still controversial. Further study is needed to confirm the reliability and reproducibility of our methods.

Prevalence and specificity of LKB1 genetic alterations in lung cancers

Germline LKB1 mutations cause Peutz-Jeghers syndrome, a hereditary disorder that predisposes to gastrointestinal hamartomatous polyposis and several types of malignant tumors. Somatic LKB1 alterations are rare in sporadic cancers, however, a few reports showed the presence of somatic alterations in a considerable fraction of lung cancers. To determine the prevalence and the specificity of LKB1 alterations in lung cancers, we examined a large number of lung cancer cell lines and lung adenocarcinoma (AdC) specimens for the alterations. LKB1 genetic alterations were frequently detected in the cell lines (21/70, 30%), especially in non-small cell lung cancers (NSCLCs) (20/51, 39%), and were significantly more frequent in cell lines with KRAS mutations. Point mutations were detected only in AdCs and large cell carcinomas, whereas homozygous deletions were detected in all histological types of lung cancer. Among lung AdC specimens, LKB1 mutations were found in seven (8%) of 91 male smokers but in none of 64 females and/or nonsmokers, and were significantly more frequent in poorly differentiated tumors. The difference in the frequency of LKB1 alterations between cell lines and tumor specimens was likely to be owing to masking of deletions by the contamination of noncancerous cells in the tumor specimens. These results indicate that somatic LKB1 genetic alterations preferentially occur in a subset of poorly differentiated lung AdCs that appear to correlate with smoking males.

Whitham method for the Benjamin-Ono-Burgers equation and dispersive shocks

The Whitham modulation equations for the parameters of a periodic solution are derived using the generalized Lagrangian approach for the case of the damped Benjamin-Ono equation. The structure of the dispersive shock is considered in this method.

Postoperative Incision Hernia in Patients with Abdominal Aortic Aneurysm and Aortoiliac Occlusive Disease: A Systematic Review

OBJECTIVES

We conducted a systematic review to determine the incidence of postoperative incision hernia in patients with abdominal aortic aneurysm compared to those with aortoiliac occlusive disease.

METHODS

Studies which compared the incidence of postoperative incision hernia in patients with abdominal aortic aneurysm and aortoiliac occlusive disease undergoing midline incision for arterial reconstruction were identified. MEDLINE was searched for articles published between January 1966 and September 2005.

RESULTS

Our search identified seven studies including data on 1132 patients, 719 with abdominal aortic aneurysm and 413 with aortoiliac occlusive disease. Pooled analysis demonstrated that patients with abdominal aortic aneurysm had a 2.9-fold increased risk of inguinal hernia (odds ratio 2.85, 95% confidence interval 1.71-4.77, p<0.0001), and a 2.8-fold risk of incisional hernia (2.79, 1.88-4.13, p<0.0001). Adjusting for other known risk factors patients with aortic aneurysm had a 5-fold increased risk of incisional hernia (5.45, 2.48-11.94, p<0.0001).

CONCLUSIONS

Patients with abdominal aortic aneurysm appear to have an approximately 3-fold increased risk for both inguinal and postoperative incision hernia compared to patients with aortoiliac occlusive disease. A large multi-centre prospective study is needed to confirm the results of this review.

Diagnostic accuracy of CT-guided percutaneous cutting needle biopsy for thymic tumours

AIM

To determine the diagnostic accuracy of computed tomography (CT)-guided percutaneous cutting needle biopsy (PCNB) for thymic tumours in accordance with the World Health Organization (WHO) classification.

MATERIAL AND METHODS

We retrospectively analysed a consecutive series of 138 cases in which CT-guided PCNB had been performed for an anterior mediastinal tumour. Its sensitivity and specificity for thymic epithelial tumours were evaluated, and the concordance between the histopathological diagnosis according to the WHO classification of thymic tumours based on PCNB and the diagnosis is based on the surgical specimens was assessed by Kappa statistic.

RESULTS

The diagnostic sensitivity and specificity of CT-guided PCNB for thymic tumours were 93.3 and 100%, respectively. The overall concordance between the diagnosis according to the WHO classification established by PCNB specimen and by the surgical specimen was 79.4% (weighted kappa=0.79).

CONCLUSION

CT-guided PCNB is a reliable method of diagnosing thymic tumours, and there was good concordance for the WHO classification between the diagnosis based on CT-guided PCNB specimen and that based on the surgical specimen.

EGFR mutations detected by high-resolution melting analysis (HRMA) as a predictor of response and survival in non-small cell lung cancer (NSCLC) patients treated with gefitinib

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Background: Recent studies have shown that EGFR mutations, mainly deletions in exon 19 (DEL) and L858R, are associated with gefitinib sensitivity in patients (pts) with NSCLC. We established a new easy method, using high-resolution melting analysis (HRMA), for detecting DEL and L858R mutations even from small biopsy or cytology samples, and evaluated the significance of EGFR mutations in NSCLC on a larger scale. Methods: Among 364 advanced or recurrent NSCLC pts treated with gefitinib between Jul 2002 and Dec 2004, HRMA was performed in 207 pts from whom specimens were available. DNA extracted from the archival tissue or cytology samples not subjected to microdissection was analyzed to detect DEL and L858R using HR-1 (Idaho Technology), an HRMA device. To validate this method, the results were compared with direct sequencing data obtained from microdissected tumor cells from surgical specimens in 66 pts. Results: Tissue/cytology/both samples were analyzed in 91/77/39 pts. EGFR mutations were detected in 85 (41%; DEL/L858R: 49/36) of the 207 pts. In the comparison with direct sequencing, consistent results were obtained from all of the 66 tissue samples, while false negative results were obtained in 2 of the 28 cytology samples. EGFR mutations were seen more frequently in women (54% vs. 31%; P = .001), never-smokers (53% vs. 32%; P = .002), and pts with adenocarcinoma (44% vs. 11%; P = .007). CR/PR/SD/PD was observed in 2/64/11/8 pts with EGFR mutations and in 0/10/23/89 pts with wild-type EGFR. The response rate (78% vs. 8%), time to progression (median, 9.1 vs. 1.6 months) and overall survival (median, 19.9 vs. 9.1 months) were all significantly superior in pts with EGFR mutations (P < .0001). Minor response and/or long SD (>6 months) was observed more frequently in SD pts with EGFR mutations than in those with wild-type EGFR (91% vs. 26%; P < .001). Among the pts with EGFR mutations, the response rate was significantly higher in the pts with DEL than in those with L858R (86% vs. 67%; P = .037). Conclusions: HRMA is a practical and precise method to detect DEL and L858R mutations. EGFR mutations strongly predict a better response and longer survival in NSCLC pts treated with gefitinib.

No significant financial relationships to disclose.

Evaluation of epidermal growth factor receptor (EGFR) mutations as predictive and prognostic indicators in patients with adenocarcinoma of the lung treated with conventional chemotherapy

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Background: EGFR mutations are associated with the responses to EGFR-tyrosine kinase inhibitors (TKI) in patients (pts) with adenocarcinoma of the lung. The E746-A750 deletion and L858R substitution mutations are the most common, as previously described. However, their implications in pts treated with conventional chemotherapy are unclear. To evaluate the predictive and prognostic value of the EGFR mutations, we studied pts with adenocarcinoma of the lung treated with conventional chemotherapy. Methods: We reviewed pts with advanced or recurrent chemotherapy naïve adenocarcinoma of the lung who received systemic chemotherapy between January 1999 and July 2001. Deletion in exon 19 and missense mutation (L858R) in exon 21 from small biopsy or cytology samples were analyzed by a high-resolution DNA melting analysis technique. Results: A total of 101 pts, all Japanese, could be analyzed. Patient characteristics were as follows: median age: 62 (37–84) years; female/ male: 39/ 62; never/ former/ current smoker: 47/ 23/ 31; and platinum-based/ non-platinum regimen: 81/ 20 (18 pts received EGFR-TKI later). 43 pts (42.6%) had EGFR somatic mutations; deletion in 24 pts, and a point mutation (L858R) in 19 pts. PR/ SD/ PD/ NE was observed in 11/ 24/ 7/ 1 pts with EGFR mutations and in 13/ 28/ 15/ 2 pts without the mutations, respectively. The response rate was similar (26% vs. 22%, p = .71) in the two subgroups. The median survival duration of the pts with EGFR mutations was 14.9 months (n = 43, including the 11 pts treated with EGFR-TKI later), as compared with 11.0 months (n = 58, including the 7 pts treated with EGFR-TKI later) in the pts without EGFR mutations (p = .09). Another analysis which handle the start of gefitinib administration as a censoring showed similar results (p = .24). Conclusions: EGFR mutations were not good predictors of tumor response to conventional chemotherapy. The overall survival tended to be longer in the pts with EGFR mutations, but prognostic value of these mutations for survival in pts with advanced adenocarcinoma of the lung was not statistically significant.

No significant financial relationships to disclose.

Primary ocular adnexal MALT lymphoma (POAML): A long-term follow up study of 114 patients (pts)

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Background: Although POAML is a recently recognized distinct entity, its natural history, prognostic factors, behavior of progression and death, and standard initial management have not been fully elucidated. Methods: 114 pts with a histologically verified POAML treated at our institution between 1970 and 2003 were retrospectively analyzed. Results: With a median follow-up duration of 5.7 years (0.6–34.0), estimated overall survival (OS) rate and progression-free survival (PFS) rate at 10 years was 89% and 57%, respectively. Older pts (>60) showed significantly worse OS (p=0.002). However, other clinical factors did not affect significantly OS or PFS. 13 (11%) pts died, but only 3 (3%) due to progressive lymphoma. 31 (27%) pts progressed, 7(6%) at systemic diseases, 8 (7%) at contra lateral sites, and 16 (14%) at the same sites, and only 2 (2%) transformed high-grade lymphoma. All 8 pts who progressed at contra lateral sites were limited to those who had involved initially in the orbit (p=0.036) and their time to progression was significantly longer (p=0.039). Pts who received initially radiation-containing therapy were superior in PFS but not OS than those initially treated with other modalities (p=0.016 and 0.091, respectively). Moreover, when we compared the outcomes of no initial therapy cohort and immediate therapy cohort, there was no significant difference in OS and PFS (p=0.499 and 0.073, respectively). Conclusions: The majority of pts with POAML showed the behaviors of very indolent diseases, and only age was significant prognostic factor. Our preliminary observation suggesting that no initial therapy is an acceptable approach for selected pts (Ann Oncol 2006;17:135–40) was further confirmed in this study for all cohorts. Considering the possible heterogeneity of POAML among initial sites suggested by the present study and the genetic heterogeneity revealed by our previous study (Blood 2005;106:289a), further investigations on POAML are warranted.

No significant financial relationships to disclose.

Identification of tumor markers and differentiation markers for molecular diagnosis of lung adenocarcinoma

To identify tumor markers and differentiation markers for lung adenocarcinoma (AdC), we analysed expression profiles of 14,500 genes against three cases of type II alveolar epithelial cells, bronchiolar epithelial cells, and bronchial epithelial cells, respectively, and 10 cases of AdC cells isolated by laser capture microdissection. Hierarchical clustering analysis indicated that AdC cells and noncancerous lung epithelial cells are significantly different in their expression profiles, and that different sets of differentiation markers are expressed among alveolar, bronchiolar and bronchial epithelial cells. Nine genes were identified as being highly expressed in AdC cells, but not expressed in noncancerous lung epithelial cells. Sixteen genes were identified as differentiation markers for lung epithelial cells. Real-time RT-PCR analysis of 45 lung AdC cases further revealed that expression of four tumor markers in AdC cells was significantly higher than that in noncancerous lung cells and that expression of ten differentiation markers was retained in a considerable fraction of lung AdC cases. Five tumor markers and seven differentiation markers were not expressed in peripheral blood cells. Similarities and differences in expression profiles between normal epithelial cells from different lung respiratory compartments and AdC cells demonstrated in this study will be informative for the molecular diagnosis of lung AdC.

Long-term follow-up results of no initial therapy for ocular adnexal MALT lymphoma

BACKGROUND

The majority of lymphomas in the ocular adnexa are low-grade B-cell lymphomas of mucosa-associated lymphoid tissue (MALT lymphoma). Although radiotherapy is the most frequently applied management, cataract and dry eye are problematic complications.

PATIENTS AND METHODS

Between 1973 and 2003, the clinical features of 36 patients with ocular adnexal MALT lymphoma with no symptoms who were managed with no initial therapy after biopsy or surgical resection were retrospectively analyzed.

RESULTS

The median patient age was 63 years (range 22-84) and all patients had stage I disease, consisting of 31 unilateral cases and five bilateral cases. With a median follow-up of 7.1 years, 25 (69%) did not require treatment. The median time until the initiation of treatment in the remaining 11 patients (31%) was 4.8 years. Six patients (17%) died, and among them only two (6%) died due to progressive lymphoma. Seventeen patients (47%) progressed, but histologic transformation was recognized in only one (3%). The estimated overall survival rates of the 36 patients after 5, 10 and 15 years were 94%, 94% and 71%, respectively.

CONCLUSIONS

In selected patients with ocular adnexal MALT lymphoma, no initial therapy might be an acceptable approach, because 70% of patients remained untreated at a median of 8.6 years, and their survival was comparable to that of reports on immediate therapy.

Preoperative measurement of the intrathrombotic pressure of a thrombosed popliteal artery aneurysm for decision of surgical indication

To evaluate the risk of rupture of a 77 mm thrombosed popliteal artery aneurysm (PAA) in an 82-year-old woman, the aneurysm was percutaneously punctured and the intrathrombotic pressure (ITP) was measured preoperatively. The percentage of the mean ITP to the mean brachial artery pressure was 80%. The aneurysm was judged to have the risk of rupture, and replacement with a prosthetic graft was performed. The percentages of the mean ITP to the mean radial artery pressure and to the mean femoral artery pressure measured intraoperatively were 83% and 71%, respectively, which approximated to the percentage measured preoperatively. PAA may have the risk of rupture even though thrombosed, and preoperative measurement of the ITP might be useful to decide surgical indication.

Stent placement for severe stenosis in the deep femoral artery with the occluded superficial femoral and popliteal arteries

In both superficial and deep femoral artery involvement, where angioplasty of the former is not suitable or feasible, angioplasty of the latter seems to be the method of choice and is a less invasive and efficient treatment particularly for limb threatening ischemia, an appropriate obstruction morphology provided. The authors describe a case of a 73-year-old man, with a rest pain of the foot and intermittent cyanosis of the toe, who underwent stent placement with transluminal angioplasty for severe stenosis in the deep femoral artery with the occluded superficial femoral and popliteal artery. The patient's ankle brachial index was remarkably increased from 0.25 to 0.61, and the preoperative symptoms were improved.

Looped reconstruction of the internal and external iliac arteries in repair of abdominal aortic or iliac artery aneurysm with a bifurcated graft

AIM

The aim of our study is to describe an original technique of distal anastomosis of a bifurcated graft, coining looped reconstruction, and our preliminary clinical experience.

METHODS

This technique has been applied in 16 of 24 distal anastomoses of 12 patients with abdominal aortic aneurysm (AAA) and/or iliac artery aneurysm. Both the internal (IIA) and external iliac arteries (EIA) are transected and anastomosed with end-to-end fashion to reconstruct their continuity, and the limb of a bifurcated graft is anastomosed to the EIA with end-to-side fashion.

RESULTS

Operative and in-hospital death, ischemic colitis, or ischemia of the lower extremities including blue toe syndrome has never occurred. All the 28 reconstructed IIAs and EIAs have been patent in 11 patients who could undergo early postoperative computed tomography scans with contrast medium.

CONCLUSIONS

The looped reconstruction of the IIA and the EIA in repair of an AAA and/or an iliac artery aneurysm with a bifurcated graft is an anatomically easy and technically simple method.

[Primary neurogenous sarcoma of the lung; report of a case]

We report a case of a 27-year-old woman with primary neurogenous sarcoma of the lung. She had no symptoms but an abnormal shadow of the right lower lung field on the chest X-ray. Chest computed tomography (CT) revealed a well defined round mass, 20 mm in maximum diameter, at the right S9. Pathological study of the specimen obtained by CT-guided percutaneous needle biopsy showed undefferentiated carcinoma. Positron emission tomography (PET) disclosed intensely increased uptake of fluoro-2-deoxy-D-glucose (FDG) at the lung lesion without other abnormal uptakes. The patient underwent right lower lobectomy of the lung and mediastinal lymph nodes dissection. Results from immunohistological study yielded a definitive diagnosis of neurogenous sarcoma. Postoperative course was uneventful, and there has been no evidence of recurrence and metastasis for more than a year after the surgery. Reported cases of primary neurogenous sarcoma of the lung are reviewed.

Extramedullary myeloid tumour (EMMT) of the gallbladder

This report describes a rare case of an extramedullary myeloid tumour (EMMT) of the gallbladder in a patient without leukaemia. A 33 year old man visited a local hospital because of jaundice. Abdominal computed tomography revealed a tumorous mass measuring 6.0 x 4.5 cm and involving the entire gallbladder. A percutaneous needle biopsy was attempted, but because adenocarcinoma could not be completely ruled out, the use of undue force was considered dangerous. Under a preoperative diagnosis of gallbladder carcinoma, a hepatopancreatoduodenectomy was performed. The tumour cells exhibited various amounts of eosinophilic cytoplasm, had medium sized round nuclei with indentation and grooving, and were strongly immunoreactive for myeloperoxidase, CD43, and c-kit protein (CD117). After surgery, the patient underwent combination chemotherapy as prescribed for cases of acute myeloblastic leukaemia. The patient did not develop acute leukaemia during a follow up period of four years. In conclusion, a correct diagnosis of EMMT can be made using appropriate immunohistochemical staining.

Japanese multicenter phase II and pharmacokinetic study of rituximab in relapsed or refractory patients with aggressive B-cell lymphoma

BACKGROUND

To evaluate the efficacy and feasibility of rituximab monotherapy in Japanese patients with relapsed or refractory aggressive B-cell lymphoma.

PATIENTS AND METHODS

Sixty-eight patients were treated with rituximab at 375 mg/m(2) by eight consecutive weekly infusions. Pretreatment variables affecting overall response rate (ORR) and progression-free survival (PFS) and the relationship between pharmacokinetic parameters and efficacy were analyzed.

RESULTS

The ORRs of 68 enrolled patients and 57 eligible patients were 35% [95% confidence interval (CI) 24% to 48%] and 37% (95% CI 25% to 51%), respectively. Median PFS of 53 evaluable patients was 52 days, whereas time to progression of 21 eligible responders was 245 days. Mild to moderate infusion-related toxicities were observed frequently at the first infusion, but all of them were reversible. Elevated lactate dehydrogenase (LDH) and refractoriness to prior chemotherapy were unfavorable factors affecting ORR and PFS (P <0.01). Serum trough levels of rituximab and area under the concentration-time curve for responders were higher than for non-responders (P <0.05).

CONCLUSIONS

Eight consecutive weekly infusions of rituximab have significant anti-lymphoma activity for relapsed or refractory aggressive B-cell lymphoma. Several pretreatment variables and serum rituximab levels are useful for predicting its efficacy.

Expression of smooth muscle markers in so called malignant fibrous histiocytomas

AIMS

To obtain further information regarding the frequency and degree of positivity for smooth muscle markers in a large number of malignant fibrous histiocytomas (MFHs), as an aid to accurate diagnosis.

METHOD

The immunohistochemical features of 100 MFHs were studied and the results were compared with those for 30 leiomyosarcomas. Eighteen cases of MFH with smooth muscle actin (SMA) positivity were examined ultrastructurally.

RESULTS

Immunoreactivity for smooth muscle markers, such as desmin, SMA, muscle specific actin (MSA) and h-caldesmon (HCD), which is a specific marker for smooth muscle cells and their tumours, was found in 28, 30, 29, and 29 of 30 leiomyosarcomas. Immunoreactivity for desmin, SMA, MSA, and HCD was found in 17, 30, 14, and two of the MFHs. On electron microscopic examination, approximately half of the cases contained a varying proportion of myofibroblastic cells. The others had only fibroblastic or undifferentiated tumour cells. At least 30% of the cases were found to display features consistent with limited smooth muscle or myofibroblastic differentiation.

CONCLUSION

A large subset of so called MFH in fact shows poorly differentiated smooth muscle or myofibroblastic features, and perhaps such tumours should be regarded as pleomorphic leiomyosarcomas and/or pleomorphic myofibroblastic sarcomas.

Hepatocyte growth factor gene transfer into the liver via the portal vein using electroporation attenuates rat liver cirrhosis

Although a variety of gene transfer methods to the liver have been designed, there are some problems such as the transfection efficiency and safety. In the present study, we developed a modified method of gene transfer into the liver by infusion of plasmid DNA via the portal vein followed by electroporation. After green fluorescence protein gene transfer, transgene expressions were detected in 24 h, and then maximally at 3 days, and persisted for 3 weeks. Histological analysis revealed that very mild tissue damage was induced in the liver to which electroporation was applied. In the second study, human hepatocyte growth factor (HGF) was more detected in the liver injected with 500 microg of human HGF gene than 100 microg of human HGF gene. However, serum HGF did not increase with 100 or 500 microg of human HGF gene. Moreover, 500 microg of HGF gene transfer into the liver by using this method could achieve the long survival of all dimethylnitrosamine-treated rats and attenuate the fibrous regions in the liver. These results suggest that HGF gene transfer into the liver via the portal vein using electroporation might be one of the useful methods for the treatment of various liver diseases.