Development and characterization of promoterless helper RNAs for the production of alphavirus replicon particle.

Alphavirus-based replicon systems are frequently used as preclinical vectors and as antigen discovery tools, and they have recently been assessed in clinical vaccine trials. Typically, alphavirus replicon RNAs are delivered within virus-like replicon particles (VRP) that are produced following transfection of replicon RNA and two helper RNAs into permissive cells in vitro. The non-structural proteins expressed from the replicon RNA amplify the replicon RNA in cis and the helper RNAs in trans, the latter providing the viral structural proteins necessary to package the replicon RNA into VRP. Current helper RNA designs incorporate the alphavirus 26S promoter to direct the transcription of high levels of structural gene mRNAs. We demonstrate here that the 26S promoter is not required on helper RNAs to produce VRP and propose that such promoterless helper RNAs, by design, reduce the probability of generating replication-competent virus that may otherwise result from RNA recombination.

T-cell receptor repertoire in matched MART-1 peptide-stimulated peripheral blood lymphocytes and tumor-infiltrating lymphocytes.

Characterization of tumor-associated antigens (TAAs) recognized by CTLs makes the consideration of therapeutic strategies based on peptide stimulation of peripheral blood lymphocytes (PBLs) feasible. Several such approaches are adoptive transfer of peptide-stimulated PBLs, ex vivo peptide stimulation of dendritic cells, and direct vaccination with TAA-derived peptides. A critical component of any of these peptide-based strategies is the requirement that the patient's PBLs are able to react productively against the presented TAA. The purpose of this study, through the study of T-cell receptor (TCR) usage, was to evaluate the T-cell response in matched MART-1(27-35) peptide-stimulated PBLs and tumor-infiltrating lymphocytes (TILs). MART-1(27-35)-reactive PBL and TIL cultures were generated from three patients by in vitro stimulation with an immunodominant peptide of MART-1 (MART-1(27-35)). All cultures had a human leukocyte antigen A2-restricted, MART-1(27-35)-specific CTL response. The TCR usage of each was assessed by the DNA sequence analysis of 50 TCR beta clones obtained by rapid amplification of cDNA ends per culture. TCR analysis suggests a TCR repertoire that differed from patient to patient (8-16 subfamilies were used) and a predominant usage of a different variable beta chain (BV) by each of these MART-reactive T cells. These predominant BV rearrangements were derived from multiple clonotypes because different variable, diversity, and junctional regions were observed. However, a similar pattern of expansion was present for both PBLs and TILs; the relative usage of each prevailing BV was more marked in TILs (36, 50, and 78% of TILs versus 26, 20, and 24% of PBLs, respectively), a broader TCR repertoire was used by PBLs (P > 0.05), and similar TCR subfamily usage was noted when TIL and PBL cultures from the same patient were compared (8 of 11, 7 of 9, and 7 of 8 for patients 1, 2, and 3, respectively). Furthermore, the exact same clonotypes derived from predominant TCR subfamilies in the PBLs and TILs were present in each patient, suggesting peptide-stimulated expansion in both biological compartments. These studies suggest that there will not be a limited and predictable TCR subfamily response to a specific TAA, although reproducible patterns of PBL and TIL expansion are present from patient to patient. Additionally, identical T-cell clonotypes having the same potential for antigen-driven expansion were present in a patient's PBLs and TILs. As such, our data support the conceptualization of approaches using adoptive transfer or vaccination based on TAA-derived peptide stimulation of PBLs.

Characterization of the functional specificity of a cloned T-cell receptor heterodimer recognizing the MART-1 melanoma antigen.

T cells can play a central role in the immune response to cancer, with tumor-specific T-lymphocyte reactivity provided by the T-cell receptor (TCR) alpha and beta chain heterodimer. This study is the first report of the definitive identification and characterization of a functional tumor-associated, antigen-specific TCR by reconstitution in an alternate cell line. Jurkat T cells were transfected with the cDNAs encoding the full-length alpha and beta T-cell receptor chains from the HLA-A2 restricted, melanoma-reactive T-cell clone, clone 5. Expression of the transfected TCR was evaluated by immunofluorescence after down-modulation of the endogenous receptor with Jurkat T-cell receptor beta chain-specific mAb. Jurkat clone 5 TCR+ cells recognized MART-1 peptides presented by T2 cells in a pattern and sensitivity equivalent to native MART-1-reactive T-cells. Recognition of HLA-A2+ melanoma cell lines by the Jurkat clone 5 TCR+ cells, however, did not occur without the addition of exogenous MART-1 peptide. The cloning and expression of functional TCR genes which are capable of specifically recognizing MART-1 antigen provides reagents which could be used for the study of the mechanisms of T-cell/tumor antigen interactions and creates immortalized reagents which can facilitate studies requiring detection of the MART-1 antigen. The tumor reactivity provided by these genes could also have application in novel immunotherapeutic strategies for treating patients with melanoma, including redirection of tumor-infiltrating lymphocyte specificity and bone marrow stem cell therapy.

In vivo administration of purified human interleukin-2 to patients with cancer: development of interleukin-2 receptor positive cells and circulating soluble interleukin-2 receptors following interleukin-2 administration.

Recent studies have demonstrated efficacy of immunotherapies including interleukin-2 (IL-2) in the treatment of malignancies in rodents and humans. High levels of IL-2 receptor-positive cells were found in the peripheral blood of patients receiving recombinant IL-2 in these Phase I clinical trials. This was demonstrated both in patients receiving i.v. IL-2 who had detectable circulating levels of IL-2 as well as in patients receiving i.p. IL-2 who did not. Up to 100% of the anti-Tac binding could be inhibited by preincubation with IL-2 indicating that this was indeed an IL-2 receptor that was identified. Two-color experiments demonstrated that few Leu 2-positive cells (less than 5-10%) but over 30% of the Leu 3-positive cells bore Tac antigen. Most of the M3-positive monocytes were Tac positive (83.7%) and negative for other T-cell (Leu-4) and nonspecific murine markers (Lyt-2 and Thy 1.2). Although normal individuals had a mean of only 186 units/ml (range, 83-335 units/ml) of soluble IL-2 receptor, patients receiving IL-2 had as much as 20,000 units/ml of soluble IL-2 receptor line in their serum. The physiological role of the IL-2 receptor identified on the cell surface of Leu 3 and M3-positive cells as well as in the serum is unclear. Soluble IL-2 receptors appeared in the circulation early following IL-2 administration, approximately 1 week prior to the detection of circulating IL-2 receptor-bearing cells. Further studies will be needed to assess the role of IL-2 in monocyte function, the precise function of IL-2 receptor-bearing Leu 3-positive cells, and the relationship of these findings to the toxicity and success of this immunotherapy in humans.

Recombinant virus vaccination against "self" antigens using anchor-fixed immunogens.

To study the induction of anti-"self" CD8+ T-cell reactivity against the tumor antigen gp100, we used a mouse transgenic for a chimeric HLA-A*0201/H-2 Kb molecule (A2/Kb). We immunized the mice with a recombinant vaccinia virus encoding a form of gp100 that had been modified at position 210 (from a threonine to a methionine) to increase epitope binding to the restricting class I molecule. Immunogens containing the "anchor-fixed" modification elicited anti-self CD8+ T cells specific for the wild-type gp100(209-217) peptide pulsed onto target cells. More important, these cells specifically recognized the naturally presented epitope on the surface of an A2/Kb-expressing murine melanoma, B16. These data indicate that anchor-fixing epitopes could enhance the function of recombinant virus-based immunogens.

MHC class I-restricted recognition of a melanoma antigen by a human CD4+ tumor infiltrating lymphocyte.

It is generally considered that MHC class I-restricted antigens are recognized by CD8+ T cells, whereas MHC class II-restricted antigens are recognized by CD4+ T cells. In the present study, we report an MHC class I-restricted CD4+ T cell isolated from the tumor infiltrating lymphocytes (TILs) of a patient with metastatic melanoma. TIL 1383 I recognized HLA-A2+ melanoma cell lines but not autologous transformed B cells or fibroblasts. The antigen recognized by TIL 1383 I was tyrosinase, and the epitope was the 368-376 peptide. Antibody blocking assays confirmed that TIL 1383 I was MHC class I restricted, and the CD4 and CD8 coreceptors did not contribute significantly to antigen recognition. TIL 1383 I was weakly cytolytic and secreted cytokines in a pattern consistent with it being a Th1 cell. The avidity of TIL 1383 I for peptide pulsed targets is 10-100-fold lower than most melanoma-reactive CD8+ T cell clones. These CD4+ T cells may represent a relatively rare population of T cells that express a T-cell receptor capable of cross-reacting with an MHC class I/peptide complex with sufficient affinity to allow triggering in the absence of the CD4 coreceptor.

RANTES secretion by gene-modified tumor cells results in loss of tumorigenicity in vivo: role of immune cell subpopulations.

An immunogenic murine fibrosarcoma cell line was genetically modified to express and produce the human RANTES chemokine stably. In in vitro chemotaxis assays purified recombinant human RANTES as well as human RANTES secreted by the modified murine tumor cells were strongly chemoattractant for mouse CD8+ /Thy-1+ tumor-infiltrating lymphocytes (TIL). RANTES production did not alter the growth of these cytokine gene-modified tumor cells in vitro, but injection of RANTES-secreting cells resulted in the abolition of the ability of those cells to form solid tumors in vivo. The growth of tumors could be restored by co-administration of monoclonal antibodies that inhibit the function of various subsets of immune cells. For example, depletion of CD8+ T cells by antibody administration resulted in complete restoration of solid tumor formation by RANTES-secreting cells, whereas depletion of the CD4+ T cell population resulted in a partial restoration of tumor formation. Additionally, administration of an anti-CR3 monoclonal antibody known to inhibit the in vivo migration of macrophages also completely restored the tumorigenicity of RANTES-secreting fibrosarcoma cells. Thus, the human RANTES chemokine can abolish tumorigenicity of an immunogenic fibrosarcoma in an in vivo murine model, and this process is mediated by various subpopulations of immune effector cells.

The persistence of human peripheral lymphocytes, tumor infiltrating lymphocytes, and colon adenocarcinomas in immunodeficient mice.

The reconstitution of severely immunodeficient mice with human peripheral blood mononuclear cells (PBMCs) may represent a unique model system to evaluate human antitumor responses. To evaluate this possibility, we studied human PBMC reconstitution, human tumor infiltrating lymphocyte (TIL) persistence, and human colon adenocarcinoma propagation in beige/nude/xid (BNX) and in severe combined immunodeficient (SCID) mice. To evaluate human PBMC reconstitution, 75 mice received 1 x 10(7)-1 x 10(9) human PBMCs i.p. or i.v. and were studied at intervals ranging from 1 to 8 weeks by fluorescence-activated cell sorting (FACS) analysis and by measurement of circulating human immunoglobulin levels. By FACS analyses, only one of 75 mice had evidence of human PBMC persistence at 2 weeks in the spleen. Moreover, liver and peritoneum showed evidence of human cells in only 13 of 56 and 16 of 55 mice, respectively. In these mice, human cells comprised 1-77% of total cells recovered. Human immunoglobulin levels in mouse serum ranged from 0 to 34,000 micrograms/ml and correlated only weakly with evidence of human PBMC reconstitution in peripheral organs, but were generally higher in SCID mice than in BNX mice. Human TIL persistence was evaluated in BNX and SCID mice that were given 3 x 10(7) TILs i.v. (in divided doses) or 1 x 10(8) i.p. TILs along with interleukin-2 administration. At 1, 2, 7, and 14 days following TIL delivery, evidence of human TIL persistence in liver, lung, peritoneum, and spleen was evaluated by FACS analysis. Fresh organ suspensions did not contain human TILs. In mice given cyclophosphamide followed by human TILs i.p., the TILs were demonstrated at 7 days in the SCID peritoneum (leu 4 = 4%) and at 2 days in the SCID spleen (leu 4 = 2%). In BNX mice, 12 of 14 fresh human colon adenocarcinomas were propagated successfully at subcutaneous sites with latency periods ranging from 1 to 13 weeks. Enzymatic disaggregation of tumors greater than 1 cm following one passage yielded 6.5-47 x 10(6) cells with viabilities ranging from 13 to 85%. We conclude that limitations and variability exist in the use of BNX and SCID mice for human PBMC reconstitution, TIL persistence, and propagation of human colon adenocarcinomas.

A biologic assay for IL-4. Rapid fluorescence assay for IL-4 detection in supernatants and serum.

Interleukin-4 (IL-4) is a lymphokine produced by activated T helper cells with effects on T cells, B cells, monocytes and mast cells. The conventional tonsillar B cell assay used for quantification of IL-4 activity is sensitive to the presence of other cytokines and requires the acquisition of fresh cells on a regular basis. We have evaluated the ability of IL-4 in the presence of antibody to IgM to induce CD23 on a cultured B cell line (Ramos) The requirements of measuring hundreds of samples at a single time precluded ready use of a conventional flow cytometer. We therefore developed a rapid fluorescence assay which allows the detection of IL-4 in supernatants and serum. The use of a particle fluorescence immunoassay reproducibly allows detection of IL-4 to 6 U in supernatants and serum. This assay is specific for IL-4 and is not sensitive to other recombinant cytokines including IL-1, IL-2, IL-3, IL-6; interferon-alpha, -beta or -gamma, tumor necrosis factor (TNF) or GM-CSF. Finally, in cancer patients receiving IL-4 its detection in serum using this assay reveals an alpha distribution phase of approximately 8 min and a beta clearance phase of approximately 48 min.

Use of soluble recombinant TNF receptor to improve detection of TNF secretion in cultures of tumor infiltrating lymphocytes.

The accurate quantitation of picogram amounts of TNF is possible by ELISA and is useful in many areas of biomedical research, including studies of TNF release in vitro by stimulated lymphocytes and macrophages, and of serum levels in patients with cancer and sepsis. However, we show in this report that the detection of recombinant TNF standards by ELISA falls over time with incubation at 37 degrees C, and is further decreased when incubated with tumor infiltrating lymphocytes (TIL), making accurate quantitation difficult. We demonstrate that the soluble dimeric form of the TNF receptor can prevent this decrease, both in the presence and absence of TIL. In contrast, the soluble monomeric TNF receptor was much less effective in preventing this decrease. In addition, the dimeric but not the monomeric TNF receptor was found to inhibit bioactivity of TNF as measured by L929 cytotoxicity. The dimeric TNF receptor does not interfere with the detection of recombinant TNF standards by ELISA, and entirely stabilizes TNF levels incubated over 48 h at 37 degrees C in the presence and absence of TIL. This protection is specific, and the TNF receptor does not stabilize interferon-gamma. The dimeric form of the soluble TNF receptor has proven useful in detecting TNF released by TIL transduced with the TNF cDNA that are currently being used in studies of the gene therapy of cancer with TIL. The dimeric TNF receptor may also prove useful in the accurate quantitation of TNF released by stimulated lymphocytes and macrophages in vitro, and in the quantitation of serum TNF levels in patients.

Mechanisms of immunologic antitumor therapy: lessons from the laboratory and clinical applications.

The use of interleukin 2-based immunotherapies for cancer has been associated with significant responses in tumor models in both mouse and humans. Further definition of the elements responsible for response is now possible. It appears that the response is associated with T-cell infiltration of the tumor, and transfer of tumor-infiltrating lymphocytes expanded in tissue culture with interleukin 2 is associated with significant antitumor effects. Further expansion of cultured human melanoma tumor-infiltrating lymphocytes with suppression of lymphokine-activated killer activity as well as the modulation of monocyte activity by interleukin 4 suggests that this cytokine may be clinically useful alone or in combination with interleukin 2. Other means of enhancing the activity of interleukin 2-based immunotherapy are suggested by the finding that tumor cell susceptibility to lysis by natural killer cells is depressed following treatment with interferon gamma and tumor necrosis factor, but susceptibility to lysis by tumor-infiltrating lymphocytes is markedly enhanced. Further development of these therapies will require innovative interpretation and application of findings related to the processing and presentation of human tumor antigens and the nature of tumor antigens and careful analysis of the T-cell receptor in antitumor effectors.

Intraperitoneal administration of interleukin-2 in patients with cancer.

We have administered 11 to 64 doses of recombinant interleukin-2 (IL-2) ranging from 10,000 to 300,000 U/kg, given three times daily as a bolus infusion through an indwelling Tenckhoff catheter, to seven patients with melanoma, ovarian carcinoma, or colorectal carcinoma. The total IL-2 dose ranged from 800 to 3800 X 10(3) U/kg. Side effects included fever, chills, nausea, vomiting, diarrhea, and major weight gain presumedly related to a capillary leak syndrome. Total weight gain ranged from 5.1 to 17.4 kg and was associated with the development of both peripheral edema and ascites. Marked eosinophilia was noted. Serum IL-2 levels were maintained at 10 to 35 U/mL for up to eight hours following intraperitoneal administration of IL-2. Increases from less than 10(4) cells/mL of a 2-L peritoneal wash to more than 10(6) cells/mL were noted in peritoneal exudate cell yields. Lysis of the natural killer target K562 increased from undetectable levels to as high as 125 lytic units per 10(6) cells. Proliferative capacity to IL-2 increased as much as 30-fold in peritoneal exudate cell yields. In addition, 70% to 80% of the mononuclear cells were T cells (Leu 4+) with intraperitoneal phenotype treatment. A single patient with pulmonary and hepatic metastases showed marked decrease in these lesions with intraperitoneal IL-2 treatment. The other patients treated intraperitoneally with IL-2 did not have significant (greater than 50%) reduction in tumor volume. These findings indicate that the intraperitoneal route of IL-2 administration may allow the in vivo development and expansion of lymphoid cells with antitumor activities.

Combined laparoscopic and endoscopic management of cholelithiasis and choledocholithiasis.

With the advent of laparoscopic cholecystectomy, optimal management of common duct stones remains controversial. Seven hundred six patients underwent laparoscopic cholecystectomy in our institution from January 1990 through January 1992. From this group of patients, 50 were identified as having clinical or radiographic evidence of common duct stones. Thirty-one patients demonstrated preoperative risk factors for common duct stones and underwent preoperative endoscopic retrograde cholangiopancreatography (ERCP). The risk factors included jaundice (19%), pancreatitis (23%), elevated liver function tests (52%), and ultrasound evidence of choledocholithiasis (6%). Preoperative ERCP was performed in 94% of patients. There were two failures due to periampullary diverticula. Common duct stones were identified in 18 patients (62%) and successfully removed by endoscopic sphincterotomy in all of these patients. Nineteen patients were found to have unsuspected common duct stones on intraoperative cholangiography. Eighteen patients (95%) underwent successful ERCP and endoscopic sphincterotomy with stone extraction. Overall, major morbidity was 2% and included one patient who experienced endoscopic sphincteroplasty. The three endoscopic failures were managed by open common duct exploration, laparoscopic duct exploration, and combined laparoscopic and open common duct exploration. We conclude that combined laparoscopic and endoscopic therapy is a viable option for the management of cholelithiasis with choledocholithiasis.

What are the contraindications for laparoscopic cholecystectomy?

Acute cholecystitis, morbid obesity, and previous upper abdominal surgery have been reported as relative contraindications to laparoscopic cholecystectomy. An analysis of 706 laparoscopic cholecystectomies performed at our institution was undertaken to determine if these relative contraindications led to increased morbidity, an increased rate of conversion to the open technique, or longer operating time. One hundred ninety-seven patients demonstrated one or more relative contraindications to laparoscopic cholecystectomy. Morbidity was not increased in patients with these risk factors, but conversion to open cholecystectomy was required in a greater percentage of patients with acute cholecystitis. We favor an attempt at laparoscopic cholecystectomy in patients with these risk factors; however, they should be counseled as to the increased risk of conversion to open cholecystectomy in the presence of acute cholecystitis.

Potential use of T cell receptor genes to modify hematopoietic stem cells for the gene therapy of cancer.

The purpose of this review is to illustrate some of the technical and biological hurdles that need to be addressed when developing new gene therapy based clinical trials. Gene transfer approaches can be used to "mark" cells to monitor their persistence in vivo in patients, to protect cells from toxic chemotherapeutic agents, correct a genetic defect within the target cell, or to confer a novel function on the target cell. Selection of the most suitable vector for gene transfer depends upon a number of factors such as the target cell itself and whether gene expression needs to be sustained or transient. The TCR gene transfer approach described here represents one innovative strategy being pursued as a potential therapy for metastatic melanoma. Tumor reactive T cells can be isolated from the tumor infiltrating lymphocytes (TIL) of melanoma patients. A retroviral vector has been constructed containing the T cell receptor (TCR) alpha and beta chain genes from a MART-1-specific T cell clone (TIL 5). Jurkat cells transduced with this virus specifically release cytokine in response to MART-1 peptide pulsed T2 cells, showing that the virus can mediate expression of a functional TCR. HLA-A2 transgenic mice are being used to examine whether transduced bone marrow progenitor cells will differentiate in vivo into mature CD8+ T cells expressing the MART-1-specific TCR. Expression of the human TCR alpha and beta chain genes has been detected by RT-PCR in the peripheral blood of HLA-A2 transgenic mice reconstituted with transduced mouse bone marrow. Expression of the TIL 5 TCR genes in the peripheral blood of these mice was maintained for greater than 40 weeks after bone marrow reconstitution. TIL 5 TCR gene expression was also maintained following transfer of bone marrow from mice previously reconstituted with transduced bone marrow to secondary mouse recipients, suggesting that a pluripotent progenitor or lymphocyte progenitor cell has been transduced.

Abdominal wall defect with liver appendage.

We present an unusual case in which an appendage of the liver was the only herniated organ through a small defect on the left lower quadrant of the abdominal wall. To our knowledge this is the first case reported with this malformation.

Should laparoscopic appendectomy be avoided for complicated appendicitis in children?

BACKGROUND/PURPOSE: Laparoscopic appendectomy is becoming the preferred technique for treating acute appendicitis. However, recent literature on adults suggests that laparoscopic appendectomy may increase the risk for postoperative infectious complications in complicated (gangrenous or perforated) cases. This study was undertaken to compare the results of open versus laparoscopic appendectomy for complicated appendicitis in children. METHODS: A retrospective review from two institutions was performed for all children treated operatively for complicated appendicitis from January 1994 through November 1996. RESULTS: Fifty-six cases were identified. Twenty-seven children underwent laparoscopic appendectomy, whereas 22 underwent open appendectomy. Seven children underwent conversion from laparoscopic to open surgery. Operating times and length of hospital stay did not differ significantly between the laparoscopic and open groups. Postoperative complications developed in 24 children (42.8%). Complications were more frequent after laparoscopic appendectomy compared with open appendectomy (56% v 18%, P = .002). A postoperative intraabdominal abscess (IAA) developed in 14 children (25%). An IAA occurred in two children after open appendectomy compared with 11 children after laparoscopic appendectomy (9% v 41%, P = .01). CONCLUSION: The findings suggest that laparoscopic appendectomy should be avoided in children who have complicated appendicitis because of the increased risk for postoperative intraabdominal abscesses. The authors propose a prospective, randomized trial to verify this finding.

Fatal refractory hyperkalemia due to tumor lysis during primary resection for hepatoblastoma.

Infants with large, rapidly growing tumors of the liver who exhibit preoperative signs of tumor necrosis (elevated uric acid or K+), having received no prior chemotherapy or radiation therapy, may be at risk for acute hyperkalemia during operative manipulation of the mass. In these patients, consideration should be given to careful monitoring of serum potassium throughout operative manipulation; cardiopulmonary bypass, to protect the heart from acute hyperkalemia; or to primary biopsy of the tumor with resection planned after chemotherapy. A case of fatal refractory hyperkalemia due to tumor lysis during a trisegmentectomy for hepatoblastoma in a 7-month-old girl who presented with a large, rapidly growing tumor and hyperuricemia is described.

Endoscopic laser ablation of obstructing congenital duodenal webs in the newborn: a case report of limited success with criteria for patient selection.

Standard approaches to intrinsic obstructing duodenal lesions in the newborn include laparotomy with enteroenterostomy, bypassing the obstruction, or duoduodenotomy with excision. The advent of improved pediatric flexible fiberoptic endoscopes and fiberoptic laser technology makes endoscopic ablation of duodenal webs and windsocks in the newborn possible.

Neurenteric cyst: surgery and diagnostic imaging.

Neurenteric cysts are rare, with fewer than 30 cases noted in the literature. We report the case of a newborn infant with respiratory distress caused by a large neurenteric cyst that was identified by prenatal ultrasound. Treatment consisted of excision of the mass through a right posterolateral thoracotomy. The cyst adhered to the spine at the level of the first thoracic vertebra and communicated with the jejunum through a posterior diaphragmatic defect. Postoperative studies with magnetic resonance imaging (MRI) and computed tomography (CT) disclosed an anterior meningocele and tethering of the spinal column. This is the second reported case of a neurenteric cyst demonstrated by prenatal ultrasound. The presence of an intrathoracic cyst associated with spinal abnormalities is characteristic of this anomaly. With imaging techniques such as MRI and CT, we may detect residual intraspinal disease associated with neurenteric cysts.