Abstract CT164: Circulating tumor DNA analysis for predictive and prognostic factors in patients with metastatic colorectal cancer: An exploratory analysis from the phase III PARADIGM study

Introduction Circulating tumor DNA (ctDNA) is an emerging biomarker used to track disease progression and treatment response. To investigate mechanisms of resistance to panitumumab and bevacizumab, we performed an exploratory analysis of ctDNA from patients (pts) with metastatic colorectal cancer (mCRC) in the ongoing phase III PARADIGM study (NCT02394834). We present an initial feasibility report of this analysis using a next generation sequencing-based platform.

Methods Pts with chemotherapy-naïve RAS wild-type mCRC were randomized 1:1 to receive mFOLFOX6 plus either panitumumab or bevacizumab. Plasma samples were taken pre- and post-treatment. Samples with a DNA yield of >10ng/mL and >10nM (assessed using an Agilent 2100 Bioanalyzer) were sequenced using an mCRC-focused ctDNA sequencing panel (PlasmaSELECTTM-R 91, PGDx) to detect mutations, amplifications, and rearrangements for 90, 26, and 3 genes, respectively, and microsatellite instability with 250kb targeted regions. Selected genes covered known pathways and functions related to CRC and sensitivity/resistance to anti-EGFR/VEGF therapies. Sequenced DNA required >12,500x average coverage, >15% mapping to regions of interest, and >75x average high quality distinct coverage; analytical validity of the panel was established using standard samples. Pre-treatment archival tissue samples were collected and analyzed by the Broad Institute Solid Tumor panel, which covers 1,072 genes with 7.3Mb targeted regions.

Results Between May 29th 2015 and June 8th 2017, 823 pts were enrolled at 197 sites. Pre-treatment plasma samples and tissue samples were collected from 756 pts (92%); >99.9% of plasma samples met the pre-specified quality criteria (QC). At the time of this feasibility analysis, 337 pre-treatment plasma samples that fulfilled the QC had been sequenced. In sensitivity validation, 92% of mutations were detected at the 0.1% mutant allele fraction (MAF) and 100% were detected at the >0.5% MAF with >99.9% specificity. In total, 25 tissue- and plasma-matched samples and 5 plasma samples without matched tissue samples were analyzed. Using individual mutations in tissue DNA as the denominator, genetic concordance was 100% (3/3) with BRAF and 70% (7/10) with TP53 between plasma and tissue samples for common TCGA mutations. Mechanisms of resistance to each therapy will be assessed by sub-clone analysis of pre- and post-treatment samples using the validated ultra-deep ctDNA sequencing panel. Collection of post-treatment samples is ongoing.

Conclusion Initial data confirms the analytical feasibility of this method and supports the use of ctDNA to track clonal evolution. Further analyses are warranted in all pts to explore the underlying mechanisms of response to treatment with anti-EGFR/VEGF therapies.

Citation Format: Katsuya Tsuchihara, Kei Muro, Takayuki Yoshino, Kohei Shitara, Kentaro Yamazaki, Mitsuyoshi Ota, Eiji Oki, Takeo Sato, Takeshi Naitoh, Yoshito Komatsu, Takeshi Kato, Kazunori Yamanaka, Ikuo Mori, Masamitsu Hihara, Jumpei Soeda, Sunita Badola, Hyunjin Shin, Takeharu Yamanaka, Kiwamu Akagi, Atsushi Ochiai, Hiroyuki Uetake. Circulating tumor DNA analysis for predictive and prognostic factors in patients with metastatic colorectal cancer: An exploratory analysis from the phase III PARADIGM study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr CT164.

Abstract 26: Panitumumab interacts with TAS-102 leading to combinational anti-cancer effects by blocking EGFR-mediated tumor response to trifluridine

Panitumumab is a monoclonal antibody raised against the human epidermal growth factor receptor (EGFR). TAS-102 is a novel chemotherapeutic agent containing trifluridine (FTD) as the active cytotoxic component. Both panitumumab and TAS-102 have been approved for the treatment of metastatic colorectal cancer (mCRC). In this study, we show the mechanism underlying the anti-cancer effects of the panitumumab/TAS-102 combination in preclinical models. Co-treatment with panitumumab and FTD exerted additive and synergistic anti-proliferative effects in LIM1215 and SW48 colon cancer cells, respectively. Consistent with the in vitro effects, panitumumab/TAS-102 combination led to tumor regression in LIM1215 and COL-01-JCK colon cancer patient-derived xenograft models. In LIM1215 cells, FTD induced ERK/Akt/STAT3 phosphorylation and subsequent serine/threonine phosphorylation of EGFR, while it had no effects on EGFR tyrosine phosphorylation. Panitumumab and the tyrosine kinase inhibitor erlotinib reduced the basal level of EGFR tyrosine phosphorylation and reversed the FTD-induced ERK/Akt/STAT3 and EGFR serine/threonine phosphorylation. These results suggested that FTD together with the basal activity of the EGFR tyrosine kinase induced downstream pro-survival signaling through ERK/Akt/STAT3. Collectively, we propose that panitumumab interacts with FTD by targeting EGFR-mediated adaptive responses, thereby exerting anti-cancer effects in combination with TAS-102. These preclinical findings provide a compelling rationale to evaluate anti-EGFR antibodies combined with TAS-102 against mCRC.

Citation Format: Kazuhide Nakamura, Yuji Baba, Toshiya Tamura, Yoshihiko Satoh, Masamitsu Gotou, Hiroshi Sawada, Shunsuke Ebara, Kazunori Shibuya, Jumpei Soeda. Panitumumab interacts with TAS-102 leading to combinational anti-cancer effects by blocking EGFR-mediated tumor response to trifluridine [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 26. doi:10.1158/1538-7445.AM2017-26

Panitumumab interaction with TAS-102 leads to combinational anticancer effects via blocking of EGFR-mediated tumor response to trifluridine

Panitumumab is a monoclonal antibody developed against the human epidermal growth factor receptor (EGFR). TAS-102 is a novel chemotherapeutic agent containing trifluridine (FTD) as the active cytotoxic component. Both panitumumab and TAS-102 have been approved for the treatment of metastatic colorectal cancer. In this study, we revealed the mechanism underlying the anticancer effects of panitumumab/TAS-102 combination using preclinical models. Panitumumab/FTD cotreatment showed additive antiproliferative effects in LIM1215 and synergistic antiproliferative effects in SW48 colon cancer cells. Consistent with the in vitro effects, panitumumab/TAS-102 combination caused tumor regression in LIM1215 and COL-01-JCK colon cancer patient-derived xenograft models. In LIM1215 cells, FTD induced extracellular signal-regulated kinase (ERK)/protein kinase B (AKT)/signal transducer and activator of transcription 3 (STAT3) phosphorylation and subsequent serine/threonine phosphorylation of EGFR, while it had no effects on EGFR tyrosine phosphorylation. Panitumumab and the tyrosine kinase inhibitor erlotinib reduced the basal level of EGFR tyrosine phosphorylation and reversed FTD-induced ERK/AKT/STAT3 and EGFR serine/threonine phosphorylation. These results suggested that FTD in combination with the basal activity of EGFR tyrosine kinase induced downstream prosurvival signaling through ERK/AKT/STAT3 phosphorylation. Collectively, we propose that panitumumab interacts with FTD by targeting EGFR-mediated adaptive responses, thereby exerting anticancer effects when used in combination with TAS-102. These preclinical findings provide a compelling rationale for evaluating the combination of anti-EGFR antibodies with TAS-102 against metastatic colorectal cancer.

Maternal obesity alters endoplasmic reticulum homeostasis in offspring pancreas

The prevalence of non-alcoholic fatty pancreas disease (NAFPD) is increasing in parallel with obesity rates. Stress-related alterations in endoplasmic reticulum (ER), such as the unfolded protein response (UPR), are associated with obesity. The aim of this study was to investigate ER imbalance in the pancreas of a mice model of adult and perinatal diet-induced obesity. Twenty female C57BL/6J mice were assigned to control (Con) or obesogenic (Ob) diets prior to and during pregnancy and lactation. Their offspring were weaned onto Con or Ob diets up to 6 months post-partum. Then, after sacrifice, plasma biochemical analyses, gene expression, and protein concentrations were measured in pancreata. Offspring of Ob-fed mice had significantly increased body weight (p < 0.001) and plasma leptin (p < 0.001) and decreased insulin (p < 0.01) levels. Maternal obesogenic diet decreased the total and phosphorylated Eif2α and increased spliced X-box binding protein 1 (XBP1). Pancreatic gene expression of downstream regulators of UPR (EDEM, homocysteine-responsive endoplasmic reticulum-resident (HERP), activating transcription factor 4 (ATF4), and C/EBP homologous protein (CHOP)) and autophagy-related proteins (LC3BI/LC3BII) were differently disrupted by obesogenic feeding in both mothers and offspring (from p < 0.1 to p < 0.001). Maternal obesity and Ob feeding in their offspring alter UPR in NAFPD, with involvement of proapoptotic and autophagy-related markers. Upstream and downstream regulators of PERK, IRE1α, and ATF6 pathways were affected differently following the obesogenic insults.

Maternal obesity programs offspring non-alcoholic fatty liver disease through disruption of 24-h rhythms in mice

BACKGROUND

Maternal obesity increases offspring propensity to metabolic dysfunctions and to non-alcoholic fatty liver disease (NAFLD), which may lead to cirrhosis or liver cancer. The circadian clock is a transcriptional/epigenetic molecular machinery synchronising physiological processes to coordinate energy utilisation within a 24-h light/dark period. Alterations in rhythmicity have profound effects on metabolic pathways, which we sought to investigate in offspring with programmed NAFLD.

METHODS

Mice were fed a standard or an obesogenic diet (OD), before and throughout pregnancy, and during lactation. Offspring were weaned onto standard or an OD at 3 weeks postpartum and housed in 12:12 light/dark conditions. Biochemical and histological indicators of NAFLD and fibrosis, analysis of canonical clock genes with methylation status and locomotor activity were investigated at 6 months.

RESULTS

We show that maternal obesity interacts with an obesogenic post-weaning diet to promote the development of NAFLD with disruption of canonical metabolic rhythmicity gene expression in the liver. We demonstrate hypermethylation of BMAL-1 (brain and muscle Arnt like-1) and Per2 promoter regions and altered 24-h rhythmicity of hepatic pro-inflammatory and fibrogenic mediators.

CONCLUSIONS

These data implicate disordered circadian rhythms in NAFLD and suggest that disruption of this system during critical developmental periods may be responsible for the onset of chronic liver disease in adulthood.

Overexpression of transforming growth factor beta1 in smooth muscle cells of human abdominal aortic aneurysm

OBJECTIVE

to examine the expression of transforming growth factor beta1 (TGF-beta1) and the cell kinetics of smooth muscle cells (SMCs) at the neck of abdominal aortic aneurysms (AAAs).

MATERIALS AND METHODS

expression of alpha-smooth muscle actin and TGF-beta1 was evaluated by immunostaining, and cell kinetics were estimated by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) assay and Ki-67 immunostaining in 11 AAAs (at both the dilated region and the neck) and eight occlusive aortas.

RESULTS

the TUNEL-positive SMC ratio in the neck and dilated region was significantly higher than in the occlusive aorta (p<0.01). The percentage of Ki-67-positive SMCs in the neck was significantly higher than in the dilated region (p<0.01) and the occlusive aorta (p=0.032). When compared with the occlusive aorta, the aneurysmal neck had increased TGF-beta1 expression (p=0.01) and reduced SMC density, and the aneurysmal dilated aorta had much more increased TGF-beta1 expression (p<0.01) and much more reduced SMC density (p<0.01).

CONCLUSIONS

these results suggest that overexpression of TGF-beta1 might be associated with the reduction of SMC density through SMC apoptosis and reduced proliferative ability of SMCs, leading to dilatation in AAAs.

Cytochrome c release into cytosol with subsequent caspase activation during warm ischemia in rat liver

Apoptosis plays an important role in liver ischemia and reperfusion (I/R) injury. However, the molecular basis of apoptosis in I/R injury is poorly understood. The aims of this study were to ascertain when and how apoptotic signal transduction occurs in I/R injury. The apoptotic pathway in rats undergoing 90 min of warm ischemia with reperfusion was compared with that of rats undergoing prolonged ischemia alone. During ischemia, mitochondrial cytochrome c was released into the cytosol in a time-dependent manner in hepatocytes and sinusoidal endothelial cells, and caspase-3 and an inhibitor of caspase-activated DNase were cleaved. However, apoptotic manifestation and DNA fragmentation were not observed. After reperfusion, nuclear condensation, cells positive for terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling, and DNA fragmentation were observed and caspase-8 and Bid cleavage occurred. In contrast, prolonged ischemia alone induced necrosis rather than apoptosis. In summary, our results show that release of mitochondrial cytochrome c and caspase activation proceed during ischemia, although apoptosis is manifested after reperfusion.

Mac-1 (CD11b/CD18) and intercellular adhesion molecule-1 in ischemia-reperfusion injury of rat liver

The chronological expression (over 24 h) of two adhesion molecules [intercellular adhesion molecule-1 (ICAM-1) and CD11b/CD18 (Mac-1)] and the extent of liver damage, including injury to sinusoidal endothelial cells (SECs) and hepatocyte apoptosis, were investigated under two conditions of rat liver ischemia-reperfusion (I/R) injury: reversible (30 min) and fatal I/R (60 min). The chronological profiles of upregulation of ICAM-1 on hepatocytes and Mac-1 showed changes in parallel with the other liver damage parameters, and the extent of upregulation and various parameters of liver injury were more advanced in the 60-min I/R group. Paradoxically, the degree of ICAM-1 upregulation of SECs decreased significantly in the 60-min I/R group vs. the 30-min I/R group. Repression of hepatocyte apoptosis by administration of the caspase inhibitor ZVAD-fmk resulted in attenuation of neutrophil infiltration and liver injury. These findings indicate that 1) neutrophil infiltration is involved in the development of liver I/R injury; 2) interaction between ICAM-1 on SECs and Mac-1 on neutrophils is not an essential step for neutrophil transmigration through the endothelial layer because SECs, specifically, were impaired in the early stages of liver I/R injury; 3) the role of ICAM-1 and Mac-1 is to adhere neutrophils firmly to hepatocytes and activate neutrophils; and 4) excessive parenchymal apoptosis may be the signal for the neutrophil-induced inflammatory and necrotic reaction.

Preliminary study for sentinel lymph node identification with Tc-99m tin colloid in patients with esophageal or gastric cancer

The purpose of this study is to determine whether a lymph node identified with high radioisotope (RI) activity is a sentinel node. We studied 26 patients with either esophageal or gastric cancer whose preoperative imaging studies showed no lymph node metastasis. Before surgery, Tc-99m tin colloid was injected via endoscopy into the submucosa. In lymph nodes dissected at surgery, RI activity was measured by a scintillation counter, and metastatic status was examined by hematoxylin-eosin staining. The number of dissected nodes was 45 +/- 15 (mean +/- SD) per patient, and the number of nodes with high RI activity was 4 +/- 1. Nodal metastasis occurred in 11 of 26 patients. In 9 of these 11 patients, metastatic foci were found in one or more nodes with high RI activity. In one of the 2 remaining patients, endoscopic clipping was applied just above the injection sites, and in the other patient, the tumor invasion was beyond the muscle layer. For further analysis, the case with clipping was excluded, and only those in which the tumor invasion was confined within the muscle layer were evaluated. Six of 18 patients in this analysis showed nodal metastasis. Each of the 6 patients had at least one node that showed high RI activity and that was positive for metastasis. We conclude that when tumor invasion remains within the muscle layer, lymph nodes with high RI activity can be regarded as sentinel nodes.

A case of gastrointestinal stromal tumor of the stomach

In a 55-year-old man, a tumor about 3 cm in diameter was detected in the upper abdomen by abdominal ultrasound screening during follow-up of chronic hepatitis C discovered in 1990. There were no symptoms and no abnormalities on physical examination. Tests for tumor markers were negative. By barium meal and gastroscopy, submucosal tumor was found on the lesser curvature of the stomach, with bridging fold in the absence of central ulceration. Biopsy revealed no tumor tissue. Under the diagnosis of submucosal tumor of the stomach, either a leiomyoma or leiomyosarcoma, partial resection of stomach was performed. Direct invasion of the surrounding organs, lymph node metastasis or distant metastasis was not observed grossly in the operation. Histologic examination of the resected specimen revealed proliferation of spindle cells and oval cells in an interlacing pattern. Immunohistochemistry for CD34, vimentin and c-kit protein was strongly positive, while smooth muscle actin, S-100 protein, desmin and p53 protein were negative. The proliferating cell nuclear antigen index was about 50%, while the MIB-1 index was < or = 1%. From these findings, this tumor was diagnosed as a gastrointestinal stromal tumor of the uncommitted type.

Staged hepatectomy after emergency transcatheter arterial embolization for ruptured hepatocellular carcinoma

BACKGROUND

Staged hepatectomy after emergency transcatheter arterial embolization (TAE) has been advocated in ruptured hepatocellular carcinoma (HCC). However, there have been no reports of clinical series of this strategy. The purpose of this study was to evaluate the protocol of this therapeutic strategy.

METHODS

Sixteen patients with suspected rupture of HCC were included in the study. After emergency TAE, tumor resectability was assessed, followed by staged hepatectomy or repeated TAE. The patients were reevaluated with regard to rupture of HCCs.

RESULTS

Primary hemostasis was achieved successfully in all patients. Eleven patients were finally judged to have experienced HCC rupture. Seven of them underwent staged hepatectomy; the other four underwent repeated TAE because their tumors were considered unresectable. Survival time tended to be longer, but not to a significant extent, in patients who underwent hepatectomy (range, 139 to 1527 days; median, 375 days) than in those treated by TAE alone (range, 43 to 1317 days; median, 158 days).

CONCLUSIONS

Staged hepatectomy after TAE is a rational treatment for patients with ruptured HCC. Although TAE is highly effective for initial hemostasis, hepatectomy appears to provide better long-term survival.

Staged hepatectomy after emergency transcatheter arterial embolization for ruptured hepatocellular carcinoma

BACKGROUND

Staged hepatectomy after emergency transcatheter arterial embolization (TAE) has been advocated in ruptured hepatocellular carcinoma (HCC). However, there have been no reports of clinical series of this strategy. The purpose of this study was to evaluate the protocol of this therapeutic strategy.

METHODS

Sixteen patients with suspected rupture of HCC were included in the study. After emergency TAE, tumor resectability was assessed, followed by staged hepatectomy or repeated TAE. The patients were reevaluated with regard to rupture of HCCs.

RESULTS

Primary hemostasis was achieved successfully in all patients. Eleven patients were finally judged to have experienced HCC rupture. Seven of them underwent staged hepatectomy; the other four underwent repeated TAE because their tumors were considered unresectable. Survival time tended to be longer, but not to a significant extent, in patients who underwent hepatectomy (range, 139 to 1527 days; median, 375 days) than in those treated by TAE alone (range, 43 to 1317 days; median, 158 days).

CONCLUSIONS

Staged hepatectomy after TAE is a rational treatment for patients with ruptured HCC. Although TAE is highly effective for initial hemostasis, hepatectomy appears to provide better long-term survival.

Twenty-four-hour profile of growth hormone in cyclic nocturnal total parenteral nutrition

OBJECTIVE

To detect the effect of the loss of alimentation rhythmicity on a circadian rhythm of human growth hormone (HGH) secretion, a 24-hour profile of HGH was studied in a growing child on cyclic nocturnal total parenteral nutrition (TPN). Twenty-four-hour profiles of substrates and metabolic hormones were also studied to evaluate the efficiency of cyclic nocturnal TPN on childhood growth.

STUDY DESIGN

Periodic blood samples from a child with megacystis-microcolon-intestinal-hypoperistalsis syndrome were obtained on five occasions, at ages 6, 7, 8, 9, and 11, when she was on cyclic nocturnal TPN.

RESULTS

Peak HGH secretion appeared with the onset of deep sleep despite the concomitant hyperglycemia and hyperinsulinemia induced by TPN at night. Smaller peaks of HGH were also observed during the noninfusion period during the day. Twenty-four-hour profiles of substrates and metabolic hormones indicated a switch from glucose use during the infusion phase to an oxidation of lipids during the noninfusion period.

CONCLUSION

The fact that the patient's growth curve remains within normal limits suggests that cyclic nocturnal TPN would be an efficient method of nutritional support. During cyclic nocturnal TPN, regular rhythm of HGH secretion occurs, and normal childhood growth is achieved.

Clinical and biochemical aspects of thiamine treatment for metabolic acidosis during total parenteral nutrition

We encountered six cases of total parenteral nutrition (TPN)-associated lactic acidosis during the 6-y period of 1988-1993. The patients were characterized by severe disease of the digestive organs, minimal food intake before surgery, and postoperative TPN with no food intake and with no vitamin supplements. Within 4 wk of TPN, they developed hypotension (< or = 80/60 mmHg), Kussmaul's respiration, and clouding of consciousness, as well as abdominal pain not directly related to the underlying disease. Routine laboratory examinations revealed no acute aggravation in hepatic, renal, or pancreatic functions. Arterial blood gas analysis showed pH < or = 7.134 and base excess < or = -17.5 mmol/L. Additional laboratory examinations revealed serum lactate > or = 10.9 mmol/L, serum pyruvate > or = 159 mumol/L, and lactate/pyruvate ratio > or = 0.029. None of the patients responded to sodium bicarbonate or other conventional emergency treatments for shock and lactic acidosis. After the first case, we suspected that thiamine deficiency might be responsible for this pathologic condition, Serum thiamine was proved to be < or = 196 nmol/L in 5 patients. Thiamine replenishment at intravenous doses of 100 mg every 12 h resolved lactic acidosis and improved the clinical condition in 3 patients. This article includes a review of 11 relevant reports published from 1982-1992 and a discussion of the biochemical mechanism of onset of thiamine deficiency-associated lactic acidosis. We emphasize the needs (1) to supplement TPN with thiamine-containing vitamins for the patients whose food intake does not meet nutritional requirements; (2) to monitor the patients routinely measuring serum thiamine concentration and erythrocyte transketolase activity during TPN; and (3) to intravenously replenish using high-dose thiamine simultaneously with the manifestation of signs and symptoms of lactic acidosis.

Small cell neuroendocrine carcinoma of the rectum

Poorly differentiated small cell neuroendocrine (NE) carcinoma of the colon and rectum is a rare primary epithelial malignancy at this location. A case of a highly aggressive NE tumor of small cell type, combined with non-invasive well-differentiated papillary adenocarcinoma in villous adenoma is reported. The patient died rapidly with massive and progressive liver metastasis. The tumor cells were argyrophilic and diffusely immunoreactive for neuronspecific enolase and synaptophysin. Ultrastructural analysis disclosed NE-type cored granules in most of the small tumor cells. NE tumors of the colon and rectum are briefly reviewed.

Three-dimensional display of the pelvic structure of anorectal malformations based on CT and MR images

Three-dimensional images of the pelvic structure of patients with anorectal malformation (ARM) were constructed by computer graphics based on radiographic computerized tomography (CT) and magnetic resonance (MR) images. Organ contour data from CT images and raw MR image data were transferred to a personal computer and to a graphic workstation respectively. On MR image processing, organs were extracted semiautomatically by thresholding enclosed areas. After several steps of image processing, three-dimensional anatomy of each anomaly was visualized with emphasis on position and shape of the muscle complex. In control patients without an anomaly, images showed that the rectum is supported by the levator muscle from behind and descends along with the urethra. In the male patient, the anal canal separates from the urethra and penetrates through the middle of the sphincter complex to reach the orifice. In those with low-type anomaly with a fistula opening to the perineum or the vestibule, images showed the fistula descending through the anterior portion of the sphincter complex. Images of those with a rectourethral fistula could show the muscle complex behind the rectum and at the region where the external sphincter should be. In those with cloacal anomalies, anatomical position and the shape of three different viscera were easily recognized, and the muscle complex was shown like that of rectourethral-type anomalies. This study is a new approach to the anomaly to facilitate understanding it and can assist a surgeon in planning a procedure. This kind of application would make it possible for a surgeon to consider the strategy on a display screen before the real surgery.

The strategy to treat disseminated neuroblastoma utilizing bone marrow transplantation: what is the surgeon's role?

The current role of surgery was evaluated in seven consecutive patients with high-risk neuroblastoma (six stage 4 patients and one stage 3, abdominal origin, and all over 12 months of age at diagnosis) treated with new modalities utilizing bone marrow transplantation (BMT). In six of these seven patients, a grossly complete excision of the primary tumor was achieved, and four have survived for 133, 69, 39, and 28 months with no further evidence of disease. The remaining patient with celiac neuroblastoma only underwent a biopsy during a second-look laparotomy after chemoradiotherapy, and thereafter developed local and distant recurrences and ultimately succumbed to the tumor. The timing of surgical intervention varied, either before or after chemotherapy, and did not appear to affect the ultimate survival. Although surgical excision of the primary tumor remains a very high priority in the overall treatment scheme, the most important factor remains the eradication of the tumor by well-planned courses of intensive chemotherapy (e.g., A1 Protocol of the Study Group of Japan). Thus, after having induced complete remission, for consolidation, it is necessary to kill all remaining tumor cells by giving supralethal doses of chemotherapy including total body irradiation (TBI) assisted by BMT.

[Detection of mycobacterial DNA by in vitro enzymatic amplification in lung nodular lesions in a patient with ovarian immature teratoma]

We experienced a 13-year-old girl with ovarian immature teratoma, who presented multiple pulmonary nodular lesions. Thoracotomy was performed to rule out the metastatic tumor. Histopathological study of the resected tumor suggested a possible diagnosis of tuberculosis. However, neither the acid-fast staining nor the mycobacterial culture of the specimens confirmed the diagnosis. Polymerase chain reaction (PCR) and hybridization technique successfully detected specific DNA sequence for M. tuberculosis from the specimens. The lesions regressed after anti-mycobacterial therapy. Detecting mycobacterial DNA by PCR, which led to a proper diagnosis and treatment of this patient, is a rapid and sensitive method in diagnosis of tuberculosis. This method is recommended to distinguish tuberculosis from neoplastic lesions of the lung, where surgical intervention is necessary.

Regional reduction in intestinal neuroendocrine cell populations in enterocolitis complicating Hirschsprung's disease

Enterocolitis (EC) remains the most serious complication of Hirschsprung's disease (HD). The aetiology of EC is uncertain. Ischemic and bacterial causes, and recently rotavirus infection, have been suggested to explain the occurrence of EC. The gut has an abundance of neuroendocrine (NE) cells which modulate gut function by endocrine, paracrine, or neurocrine routes. We studied NE cell populations in the bowel from 16 patients with HD (six of whom had clinical evidence of EC) and rectal tissue from 6 controls. Immunohistochemical studies were carried out using monoclonal and polyclonal antibodies against chromogranin A, synaptophysin (general markers of NE cells), 5-Hydroxytryptamine (5-HT), somatostatin, peptide YY (PYY), and glucagon/glicentin (neuropeptides). The six patients who had clinical evidence of EC prior to defunctioning colostomy showed histological evidence of EC in the defunctioned bowel. Using immunocytochemistry and serial tissue sectioning it was found that the number of NE cells in the aganglionic segment of colon in patients with HD was significantly (P < .05) increased compared with the numbers in the ganglionic segment. However, in the ganglionic colon, there was a significant (P < .05) reduction in NE cells in EC patients compared with non-EC patients. These results were seen both with the generic endocrine cell marker chromogranin A, which stains virtually all endocrine cells, and with specific markers for 5-HT, PYY, and glucagon/glicentin, which identify distinct subpopulations of endocrine cells. These differences may be partially responsible for previous conflicting reports of NE cell distribution in HD.(ABSTRACT TRUNCATED AT 250 WORDS)

Use of cultured human epidermal allografts for the treatment of extensive partial thickness scald burn in children

In spite of recent progress in burn treatment, the early surgical therapy of partial thickness scald burns in children is still controversial. Early tangential excisions is not easily applicable for these patients because of difficulties in determination of the burn depth and probable physiological derangement after surgery. Hypertrophic scar formation and wound contraction after meshed autografts are other limitations. For these reasons, conservative treatment, not early excision therapy, has been chosen initially for these injuries. We used cultured epidermal allografts for extensive, partial thickness scald burns, during the early post-burn period without escharectomy. Fifty to 100% of the engrafted superficial dermal burns were epithelialized within 7 days. In contrast, untreated identical wounds remained open. Repeated grafting of cultured allografts on unexcised wound granulations of dermal burns also enhanced epithelialization. Long term results showed that hypertrophic scar formation in the mixed superficial and deep dermal burns was reduced when cultured allografts were used. Allografting of the cultured epidermis without surgical excision apparently promoted the rapid regeneration of the partial thickness burns. Procedural complications did not occur. Cultured allografts should be used as an effective and safe biological dressing for partial thickness scald burns in children.

Mucosal neuroendocrine cell abnormalities in the colon of patients with Hirschsprung's disease

We studied the distribution of mucosal neuroendocrine (NE) cells in the colon from 13 patients with Hirschsprung's disease (HD) and from 8 controls. Immunohistochemical studies were carried out using monoclonal and polyclonal antibodies against chromogranin A and synaptophysin (general markers of NE cells), 5-hydroxytryptamine (5-HT) (a marker of amine), peptide YY (PYY), and somatostatin (markers of neuropeptides). Chromogranin A immunoreactive cells were significantly increased in the aganglionic bowel compared with ganglionic bowel and controls (P less than .05). There was an increase in the number of synaptophysin immunoreactive cells in the aganglionic bowel compared with ganglionic bowel and controls but the results were not statistically significant. 5-HT immunoreactive cells were also significantly increased in the aganglionic bowel compared with ganglionic bowel and controls (P less than .05). The immunostaining for PYY demonstrated abundance of this NE cell type in the aganglionic bowel and this was highly significant compared with ganglionic bowel and controls (P less than .001). There was a significant increase in somatostatin immunoreactive cells in the aganglionic bowel compared with ganglionic bowel (P less than .01). The increase in neuroendocrine cells was found over the entire length of the aganglionic segment in rectosigmoid HD as well as in long-segment HD. These results demonstrating the increased levels of NE cells in the mucosa of aganglionic colon suggest that the NE cells may have a role in regulating the sustained contraction of the aganglionic intestine in HD.

Abscessed leiomyosarcoma of the ileum

A-49-year-old man was admitted because of a lower abdominal mass. During the five days prior to admission, he had noted fever and lower abdominal pain. Palpation of the abdomen revealed a tender mass, 10 cm in diameter, in the suprapubic region. An x-ray revealed an irregular collection of gas, 9 cm in diameter, in the pelvic cavity, which appeared as a mirror image when the patient was upright. Based on the physical finding and the results of a barium enema, abdominal CT, MRI, and small intestine imaging, a diagnosis of leiomyosarcoma of the ileum was made. Excision of the tumor and part of the small intestine was performed. A saccular tumor, 11 x 6 x 5 cm, was found 1.0 m from the cecum and growing out of the wall of the ileum. A large amount of pus was found inside the cavity. The pathological diagnosis was leiomyosarcoma.

[Gastrointestinal bleeding in children]

The site and nature of lesions producing gastrointestinal bleeding was evaluated in pediatric patients admitted to Tokai University Hospital. The differential diagnosis was possible based upon the character of the bleeding and the age of the patient. Upper endoscopy is the diagnostic maneuver of choice in evaluating the upper gastrointestinal bleeders. Sigmoidoscopy, colonoscopy, technetium scans, tagged red cell scans and intraoperative angiography were helpful in locating bleeding sites of lower bleeders. Common causes of bleeding were as follows: Hemorrhagic disease, necrotizing enterocolitis, and midgut volvulus in neonates; intussusception and internal hernia in infants; juvenile polyp and infectious diarrhea in children; duodenal ulcer and ulcerative colitis in adolescents. Gastro-duodenal ulcers were found in all age groups. One neonate died of indomethacin induced bleeding, however, bleeding from acute ulcer was usually controlled by conservative treatments. Increasing frequency of variceal bleeding due to portal hypertension after successful Kasai procedure for congenital biliary atresia was emphasized.

[Tracheoesophageal anastomosis for intractable aspiration pneumonia]

Permanent tracheostomy and tracheoesophageal anastomosis were performed as a means of surgical intervention for the treatment of intractable aspiration pneumonia. Conventional method of tracheoesophageal anastomosis has entailed various problems. The improved technique by the authors utilized the special histological features of the situation and makes possible safe and reliable anastomosis. This technique retains the tracheal perichondrium to strengthen the anastomosed portion of the trachea, and can thus prevent suture insufficiency due to tension upon the anastomotic site.