Prognostic significance of lymph node yield in ypN0 rectal cancer.

BACKGROUND: Neoadjuvant radiation therapy for locally advanced rectal adenocarcinoma decreases lymph node yield. This study investigated the association between survival and number of lymph nodes evaluated in patients with pathologically negative nodes after neoadjuvant therapy. METHODS: Patients with locally advanced rectal adenocarcinoma who underwent neoadjuvant therapy and had pathologically negative lymph nodes were included from the Surveillance, Epidemiology, and End Results (SEER) database over a 7-year interval (January 2004 to December 2010). Systematic dichotomization for optimal cut-off point identification was performed using statistical modelling. RESULTS: A total of 3995 patients met the inclusion criteria. The majority had T3 (66·7 per cent) and moderately differentiated (71·5 per cent) tumours. The median number of lymph nodes retrieved was 12 (i.q.r. 7-16). An optimal cut-off of nine lymph nodes was identified. Increasing age (P < 0·001), increasing T category (T4 versus T1, P < 0·001; T3 versus T1, P = 0·010), response to neoadjuvant therapy (P < 0·001) and number of nodes evaluated (P < 0·001) were significant factors for overall survival in univariable analysis. After adjustment in the multivariable model, the group with nine or more nodes examined had significantly better overall survival (hazard ratio (HR) 0·76, 95 per cent c.i. 0·65 to 0·88, P < 0·001; 5-year survival 83·2 versus 78·0 per cent) and cancer-specific survival (HR 0·76, 0·64 to 0·92, P = 0·004; 5-year survival 87·9 versus 85·1 per cent) than the group with one to eight nodes examined. CONCLUSION: Overall and cancer-specific survival were worse where fewer than nine lymph nodes were identified after neoadjuvant therapy for locally advanced rectal cancer.

Identification of a neutral loss from precursor ions with nearly Gaussian-shaped isotopic patterns via inverted isotopic patterns of product ions.

RATIONALE: Direct atomic composition determination of ions with very broad Gaussian-shaped isotopic patterns is challenging because no monoisotopic peak is available for high accurate mass determination and no characteristic shapes in isotopic patterns are visible. METHODS: Isolation and fragmentation of the ions corresponding to one peak (one nominal mass) in the center of the broad Gaussian-shaped isotopic pattern lead to a mass spectrum with the product ion signal showing the inverted full isotopic profile of the neutral fragment. RESULTS: We have introduced a convenient method for the fast and straightforward identification of a neutral loss for molecular ions with broad isotopic patterns. The theoretical considerations underlying this method are explained and its practical limitations are considered. The benefits of this method are exemplified by guiding a reader through the analysis of a complex mixture of bridged carborate clusters, compounds with very broad isotopic patterns. CONCLUSIONS: The presented method can be efficiently used for the determination of atomic compositions of compounds with broad isotopic patterns by their fragmentation using mass spectrometry. This method should significantly facilitate the mass spectrometric analysis of compounds containing several atoms with broad isotopic distributions, such as Ge, Sn, Mo, Ru and Hg, and, thus, can considerably broaden the use of mass spectrometry as an analytical method in inorganic and organometallic chemistry. Copyright © 2016 John Wiley & Sons, Ltd.

Evaluating new processes and concepts for energy and resource recovery from municipal wastewater with life cycle assessment.

Energy and resource recovery from municipal wastewater is a pre-requisite for an efficient and sustainable water management in cities of the future. However, a sound evaluation of available processes and pathways is required to identify opportunities and short-comings of the different options and reveal synergies and potentials for optimization. For evaluating environmental impacts in a holistic view, the tool of life cycle assessment (LCA, ISO 14040/44) is suitable to characterize and quantify the direct and indirect effects of new processes and concepts. This paper gives an overview of four new processes and concepts for upgrading existing wastewater treatment plants towards energy positive and resource efficient wastewater treatment, based upon an evaluation of their environmental impacts with LCA using data from pilot and full-scale assessments of the considered processes.

Predictive role of imaging in sentinel lymph node dissection for melanoma.

A retrospective study of 67 patients with metastatic melanoma was performed to evaluate if imaging from lymphoscintigraphy could predict a higher miss rate if only the most radioactive node were removed. Following protocol for sentinel node biopsy, the surgeon resected all lymph nodes containing radioactivity > 10% of the most radioactive node. A correlation was performed between the radioactive counts of the lymph nodes and the presence of metastases. The percentage of cases in which the most radioactive node was negative for metastasis on pathology was calculated. Two nuclear medicine physicians read the images from lymphoscintigraphy specifically to determine if the first lymph node visualized became less intense than other nodes on later images. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. In 13 of 67 (19%) patients, the most radioactive lymph node was negative for metastasis while a less radioactive node contained metastatic disease. Consensus reading by the nuclear medicine physicians determined that in 9 cases, the first lymph node visualized became less intense than another lymph node on later images. Of the 9 cases, 4 were true positive and 5 were false positive when correlated with intraoperative count rate and pathology. Of the cases where the most radioactive node was not positive on histopathology (n = 13), the consensus reading by the nuclear medicine physicians reported 4 of them (31%). Imaging by lymphoscintigram had a sensitivity 31%, specificity 91%, positive predictive value 44%, and negative predictive value 85% for predicting whether the most radioactive lymph node at surgery would be negative for metastasis at pathology. We conclude that in patients with melanoma, lymphoscintigraphy has high specificity and negative predictive value but modest sensitivity and positive predictive value for detecting when the sentinel node will not be the most radioactive lymph node during sentinel lymph node dissection. These findings support that dynamic imaging by lymphoscintigraphy has a role in surgical planning but that the imaging protocol could benefit from further optimization.

Decreased expression of eukaryotic initiation factor 3f deregulates translation and apoptosis in tumor cells.

The eukaryotic initiation factor 3f (eIF3f) is the p47 subunit of the multi-subunit eIF3 complex. eIF3 plays an important role in translation initiation. In the present study, we investigate the biological function of eIF3f in translation and apoptosis in tumor cells. We demonstrated for the first time that eIF3f is downregulated in most human tumors using a cancer profiling array and confirmed by real-time reverse transcription PCR in melanoma and pancreatic cancer. Overexpression of eIF3f inhibits cell proliferation and induces apoptosis in melanoma and pancreatic cancer cells. Silencing of eIF3f protects melanoma cells from apoptosis. We further investigated the biological function of eIF3f. In vitro translation studies indicate that eIF3f is a negative regulator of translation and that the region between amino acids 170 and 248 of eIF3f is required for its translation regulatory function. Ectopic expression of eIF3f inhibits translation and overall cellular protein synthesis. Ribosome profile and ribosomal RNA (rRNA) fragmentation assays revealed that eIF3f reduces ribosomes, which may be associated with rRNA degradation. We propose that eIF3f may play a role in ribosome degradation during apoptosis. These data provide critical insights into the cellular function of eIF3f and in linking translation initiation and apoptosis.

Investigating sun-damaged skin and actinic keratosis with optical coherence tomography: a pilot study.

Actinic Keratosis (AK) arises from sun-damaged skin and is the first clinical manifestation in the multistep process of skin carcinogenesis to invasive squamous cell carcinoma. Thus, it is an ideal target for chemopreventive efforts. Noninvasive measures of AK severity are needed to assess the efficacy of chemoprevention agents. We performed a pilot study on 20 participants to investigate the OCT appearance of sun-protected skin of the upper inner arm as well as sun-damaged skin and early AKs of the dorsal forearms, and to determine if features or quantitative measures in Optical Coherence Tomography (OCT) images could be used to reliably differentiate between these categories. OCT images of upper inner arm (normal appearing skin) showed skin layers and features (stratum corneum, epidermis, dermis, blood vessels) seen in previous studies; additionally in this participant group the subcutaneous fat layer was usually identified. Sun-damaged skin was characterized by increased signal in the epidermis and rapid attenuation of light. AKs were diverse in appearance but frequently characterized by high surface reflection, the presence of a low-signal band in the stratum corneum, and heterogeneous appearance in the epidermis/dermis. Significant differences were found between skin categories using measures of stratum corneum and epidermal/dermal depths and intensities. The presence of a dark band in the stratum corneum was 79% sensitive and 100% specific for AK. This study indicates that OCT holds promise as a useful technique for identifying and characterizing AKs and monitoring their response to chemoprevention agents.

Chemoprevention of human actinic keratoses by topical 2-(difluoromethyl)-dl-ornithine.

Alpha-2-(Difluoromethyl)-dl-ornithine (DFMO), an irreversible inhibitor of ornithine decarboxylase, has been shown to suppress skin carcinogenesis in murine models after oral or topical administration. We designed a randomized, placebo-controlled study using a topical hydrophilic ointment formulation with or without 10% (w/w) DFMO. Forty-eight participants with moderate-severe actinic keratoses (AKs) on their forearms (i.e., at least 10 well-circumscribed lesions on the lateral surface) completed a 1-month run-in on placebo ointment. Before randomization, all lateral forearm AKs were circled, counted, photographed, and skin biopsies were obtained for DFMO and polyamine levels. Then participants were randomized to receive DFMO ointment on the right versus the left forearm and placebo hydrophilic ointment on the contralateral forearm twice daily for 6 months. DFMO was not detected in the blood of any subject, and there were no systemic toxicities. None of a subsample of 17 placebo forearms had measurable concentrations of DFMO, whereas 13 of the corresponding DFMO-treated forearms had high DFMO skin levels. As compared with placebo, the 6-month DFMO treatment caused a 23.5% reduction in the number of AKs (P = 0.001) as well as significant suppression of AK biopsy spermidine levels (26%; P = 0.04). Seven of the 48 (14.6%) participants experienced severe (2; 4.2%) or moderate (5; 10.4%) inflammatory reactions on their DFMO-treated arms which required dosing modification. Topical DFMO for 6 months can reduce the number of AK lesions and skin spermidine concentrations in high-risk participants and deserves additional study as a skin cancer chemopreventive agent.

Relationship of p53 mutations to epidermal cell proliferation and apoptosis in human UV-induced skin carcinogenesis.

Human skin is continually subjected to UV-irradiation with the p53 gene playing a pivotal role in repair of UV-induced DNA damage and apoptosis. Consequently, p53 alterations are early events in human UV-induced skin carcinogenesis. We studied 13 squamous cell carcinomas (SCC), 16 actinic keratoses (AK), 13 samples adjacent to an AK (chronically sun-damaged), and 14 normal-appearing skin samples for p53 mutation, p53 immunostaining (IHC), apoptosis (in situ TUNEL and morphology), and proliferation (PCNA). The frequency of p53 mutation increased from 14% in normal skin, to 38.5% in sun-damaged skin, 63% in AK, and 54% in SCC. p53 IHC increased similarly. Apoptosis (TUNEL) increased from 0.06 +/- 0.02%, to 0.1 +/- 0.2, 0.3 +/- 0.3, and 0.4 +/- 0.3 in normal skin, sun-damaged skin, AK, and SCC, respectively. Apoptosis was strongly correlated with proliferation (i.e., TUNEL and PCNA, r = 0.7, P < 0.0001), and proliferation was significantly increased in the progression from normal skin to SCC. Bax was significantly increased in SCC compared to AK. These data imply that apoptosis in samples with a high frequency of p53 mutation may not necessarily be p53-dependent. We suggest that there is a mechanism for apoptosis in response to increased cellular proliferation that is p53-independent.

The stress-response proteins poly(ADP-ribose) polymerase and NF-kappaB protect against bile salt-induced apoptosis.

Bile salts induce apoptosis and are implicated as promoters of colon cancer. The mechanisms by which bile salts produce these effects are poorly understood. We report that the cytotoxic bile salt, sodium deoxycholate (NaDOC), activates the key stress response proteins, NF-kappaB and poly(ADP-ribose) polymerase (PARP). The activation of NF-kappaB and PARP, respectively, indicates that bile salts induce oxidative stress and DNA damage. The pre-treatment of cells with specific inhibitors of these proteins [pyrrolidine dithiocarbamate (NF-kappaB inhibitor) and 3-aminobenzamide (PARP inhibitor)] sensitizes cells to the induction of apoptosis by NaDOC, indicating that these stress response pathways are protective in nature. Colon cancer risk has been reported to be associated with resistance to apoptosis. We found an increase in activated NF-kappaB at the base of human colon crypts that exhibit apoptosis resistance. This provides a link between an increased stress response and colon cancer risk. The implications of these findings with respect to apoptosis and to colon carcinogenesis are discussed.

Chromosomal and genetic alterations of 7,12-dimethylbenz[a]anthracene-induced melanoma from TP-ras transgenic mice.

The TP-ras transgenic mouse line expresses an activated human T24 Ha-ras gene with a mutation in codon 12, regulated by a mouse tyrosinase promoter. The transgene is expressed in melanocytes of the skin, eyes, and brain. The mice develop cutaneous melanoma when treated with 7,12-dimethylbenz[a]anthracene. Cell lines have been generated from the cutaneous tumors and metastatic lesions. By using fluorescence in situ hybridization with mouse whole chromosome paints, the cell lines were characterized for chromosomal abnormalities. Key findings in the tumor cells included translocations of chromosome 4 and alterations in chromosome 6. One tumor cell line contained a double translocation involving chromosomes 3 and 6. To extend the results of the chromosome 4 painting, Southern analysis of the p15INK4B, p16INK4A, and p19INK4D genes was performed. Our data indicated that there were homozygous and partial allelic deletions and polymorphisms in the region of chromosome 4 containing these genes, resulting in the absence or reduced expression of the p16 product. These findings are similar to those reported for human melanoma, and the TP-ras transgenic mouse may therefore be a valuable model for studying novel strategies for melanoma prevention and treatment.

Phase I study of direct gene transfer of an allogeneic histocompatibility antigen, HLA-B7, in patients with metastatic melanoma.

PURPOSE: To determine the safety, toxicity, and efficacy of direct intratumoral injection of an allogeneic major histocompatibility complex (MHC) class I gene, HLA-B7, in a cationic lipid vector (Allovectin-7; Vical Inc, San Diego, CA) in patients with metastatic melanoma. PATIENTS AND METHODS: Seventeen HLA-B7-negative patients were treated with intralesional injection of Allovectin-7. Twelve patients received a single intralesional injection containing 10 micrograms (four patients), 50 micrograms (five patients), or 250 micrograms (three patients) of plasmid DNA. Five patients received two or three injections of 10 micrograms DNA to a single tumor site at 2-week intervals. Tumor biopsies pretherapy and 2 and 4 weeks after gene injection were obtained to determine expression of the plasmid by polymerase chain reaction (PCR), reverse transcriptase (RT)-PCR, flow cytometry, and immunohistochemistry. RESULTS: Toxicities were related to technical aspects of the injections or biopsies. These included pain, hemorrhage, pneumothorax, and hypotension. Two patients were hospitalized overnight for observation. Seven patients (50%) had tumor responses insofar as the injected nodule decreased > or = 25% by radiologic or physical examination. One patient with a single site of disease achieved a complete remission. Ninety-three percent of the patients' post-gene therapy biopsies contained HLA-B7 plasmid DNA, mRNA, or protein. CONCLUSION: Intratumoral injection of the allogeneic histocompatibility gene, HLA-B7, in a lipid vector can be performed safely at plasmid DNA doses < or = 250 micrograms. The safety profile and biologic activity of this therapy warrants further studies to define the mechanism of action, predictors of response, and antitumor efficacy of this approach.

Lumpectomy and radiation treatment for invasive lobular carcinoma of the breast.

BACKGROUND: Large studies have shown a similar outcome when comparing mastectomy with lumpectomy and external beam radiation therapy in the treatment of infiltrating ductal carcinoma. However, this has not been studied extensively for invasive lobular carcinoma. We studied the pattern of recurrence and overall survival of patients treated with lumpectomy and radiation for either invasive lobular carcinoma (ILC) or combined invasive lobular carcinoma/invasive ductal carcinoma (ILC/IDC) of the breast. DESIGN: A retrospective chart review was performed for 111 patients with ILC or ILC/IDC who were diagnosed and/or treated at the university hospital between 1984 and 1994. RESULTS: Of the 111 patients, 93 had stage I or II tumors. Thirty-four patients (37%) were treated with lumpectomy and adjuvant postoperative radiotherapy with one (3%) local recurrence and a mean overall survival of 83.6 months. Fifty-nine patients (63%) were treated by modified radical mastectomy with two local recurrences (3%) and a mean overall survival of 71.7 months. CONCLUSIONS: Patients with ILC or ILC/IDC can be effectively treated with lumpectomy and radiation for stage I and II tumors while maintaining a low risk of local recurrence and equivalent overall survival.

Thioredoxin and thioredoxin reductase gene expression in human tumors and cell lines, and the effects of serum stimulation and hypoxia.

Thioredoxin and thioredoxin reductase are redox proteins that have been implicated in the control of cell proliferation and transformation. We report the levels and activity of these proteins and their mRNAs in human primary tumors and tumor cell lines. Half of human primary colorectal carcinomas (5/10) examined had increased thioredoxin mRNA, of 3- to over 100-fold, compared to adjacent normal colonic mucosa from the same subject. Thioredoxin reductase protein and activity were increased an average of 2-fold in human colorectal tumors compared to normal mucosa. A number of human hematologic and solid tumor cell lines were studied and showed a 10-fold range of thioredoxin mRNA and a 23-fold range of thioredoxin reductase mRNA. Increased proliferation and hypoxia are factors that might contribute to the increased expression in solid tumors. We found that serum stimulation of growth arrested MCF-7 breast cancer cells caused a 59% increase in thioredoxin mRNA and a 62% increase in thioredoxin reductase mRNA by 24 hours. Exposure of HT-20 colon cancer cells to hypoxia resulted in a 14-fold increase in thioredoxin mRNA by 16 hours, and a transient 4-fold increase in thioredoxin reductase mRNA at 1 hour that had returned to control levels by 8 hours. Cancer cells were found to release thioredoxin into the medium at rates between 1 to 2 pmole/10(6) cells/3 hours. The rate of secretion was not, however, related to cellular-levels of thioredoxin. The results of the study show that the expression of thioredoxin and thioredoxin reductase are increased several fold in some human solid tumors compared to normal tissue. Secretion of thioredoxin, which is known to have a direct growth stimulating activity, by human tumor cells might lead to the stimulation of cancer cell growth.

Aspiration pneumonia following surgically placed feeding tubes.

BACKGROUND: The enteral route is preferred in surgical patients requiring nutritional support; however, controversy surrounds the choice of location of feeding tube placement. Although jejunostomy has been commonly accepted as superior to gastrostomy for long-term nutritional support because of an assumed lower risk of aspiration pneumonia, recent studies suggest that reevaluation of common practices of surgical tube placement is warranted. PATIENTS AND METHODS: We conducted a retrospective chart review of gastrostomy and jejunostomy procedures from 1986 to 1993. Demographic information and complications related to the procedure were reviewed. Aspiration pneumonia was defined as respiratory symptoms, leukocytosis, and infiltrate on chest radiograph. RESULTS: Sixty-nine gastrostomies and 86 jejunostomies were performed during the study period. Six patients were diagnosed with aspiration pneumonia; 2 cases of which occurred with jejunostomy and 4 cases occurred with gastrostomy (P = not significant). CONCLUSIONS: There was no difference in rates of pulmonary aspiration or other complications between gastrostomy and jejunostomy. We suggest that when a surgically placed feeding tube is required, the determination of appropriate procedure be based on clinical factors such as the technical difficulty of the operation or long-term feeding goals.

Abdominal wall hernias in patients with abdominal aortic aneurysmal versus aortoiliac occlusive disease.

BACKGROUND: This study was undertaken to determine the incidence of ventral incisional hernias (VIHs) and inguinal hernias (IHs) in patients with abdominal aortic aneurysmal (AAA) versus those with aortoiliac occlusive disease (AIOD). PATIENTS AND METHODS: The medical records of 193 patients (128 with AAA and 65 with AIOD) who had undergone elective aortic reconstruction were reviewed to determine the number and location of abdominal wall hernias (AWHs). RESULTS: Forty-one AWHs (28 IHs and 13 VIHs) were detected in patients with AAA compared to 13 (11 IHs and 2 VIHs) in patients with AIOD. There was a significantly greater incidence of VIHs in patients with AAA versus patients with AIOD (10% versus 3%, P < 0.05) and recurrent AWHs (28% versus 19%, P < 0.01), but not of IHs (22% versus 17%). CONCLUSION: Patients with AAA have a higher incidence of VIHs and recurrent AWHs--without a corresponding increase in patient-related risk factors--than patients without aneurysm, suggesting that as yet unidentified etiologic factors may contribute to the development of AWHs in these patients.

Influence of local treatment on the recurrence rate of ductal carcinoma in situ.

BACKGROUND: Screening mammography has resulted in a significant increase in the diagnosis of ductal carcinoma in situ (DCIS). The role of breast conservation therapy and the long-term recurrence rate are still controversial. This article compares mastectomy, wide excision alone, and wide excision with radiation as treatments for DCIS. STUDY DESIGN: One hundred twenty-four cases of DCIS were retrospectively reviewed and were found to be pure DCIS by a senior pathologist. The mean age at diagnosis was 60 years (range, 33 to 81). Originally, 101 patients (81 percent) presented with calcification on mammogram, and 23 (19 percent) presented with a palpable mass. Histologic data showed that 54 (44 percent) had noncomedo type lesions, 46 (37 percent) had comedo type, and 24 (19 percent) had unknown type DCIS. RESULTS: Four of the 124 patients had a recurrence during a mean follow-up period of 43 months. Recurrence is defined as any development of DCIS or invasive carcinoma in the ipsilateral breast. There was one (1.3 percent) recurrence in the 75 patients treated with mastectomy (an adenocarcinoma of the chest wall), which occurred at 59 months. Treatment was 5,750 cGy to the chest wall and the patient is free of disease 37 months postradiation. There were three (11 percent) recurrences at 14, 21, and 29 months, respectively, in the 28 patients treated with wide excision alone. All three recurrences were found by calcifications on mammogram and all patients had comedo type original lesions. Two recurrences were pure DCIS of the breast. Both patients were treated with mastectomy and are free of disease at 33 and five months, respectively. The third recurrence was an invasive colloid carcinoma of the breast. Treatment was a modified radical mastectomy; the patient is free of disease after 62 months. There were no recurrences in the 21 patients who were treated with wide excision and radiation. Average total dose of radiation was 5,835 cGy (range, 4,500 to 6,480). CONCLUSIONS: The results of this study indicate that both mastectomy and wide excision with radiation are associated with very low recurrence rates. Wide excision alone is associated with a higher recurrence rate. However, all recurrences were detected mammographically and all lesions were salvaged by mastectomy. Therefore, the ultimate local control and survival rates were similar for all three modalities.

Stereotactic fine-needle aspiration cytology of nonpalpable breast lesions: an analysis of 258 consecutive aspirates.

BACKGROUND: The role of stereotactic fine-needle aspiration cytology (SFNAC) in the diagnosis of nonpalpable breast lesions is poorly defined. PATIENTS AND METHODS: Data were prospectively collected from 225 consecutive patients with nonpalpable breast lesions who had aspiration cytology followed by immediate surgical excision. RESULTS: Between 1988 and 1993, 258 such procedures were performed. The results of 84 (33%) were interpreted as benign, 84 (33%) as atypical, 28 (11%) as suspicious for malignancy, and 49 (19%) as malignant. In all, 88 (34%) surgical specimens were malignant. SFNAC had an 80% sensitivity, a 96% specificity, a 91% positive predictive value, and an 89% negative predictive value. There were 18 false-negative and 7 false-positive aspirates. CONCLUSIONS: SFNAC for diagnosing nonpalpable breast lesions is moderately sensitive and highly specific, and has a high positive and negative predictive value. In conjunction with mammography and clinical assessment, the procedure is useful for determining which patients with nonpalpable breast lesions may require surgical biopsy.

Contraindications and complications of laparoscopic cholecystectomy.

Laparoscopic cholecystectomy is a commonly performed procedure for the removal of symptomatic gallstones. Compared with open cholecystectomy, laparoscopic cholecystectomy is associated with less postoperative pain, earlier discharge from the hospital and a more rapid recovery. However, there are specific contraindications to the procedure, including empyema of the gallbladder, gangrenous cholecystitis, coagulopathy, portal hypertension and peritonitis. Complications from laparoscopic cholecystectomy include common duct injury, bleeding, bile leakage and wound infection. An understanding of these issues allows the family physician to more appropriately select patients for laparoscopic removal of the gallbladder.

The failure of conventional methods to promote spontaneous transpyloric feeding tube passage and the safety of intragastric feeding in the critically ill ventilated patient.

Nasoenteral tube feedings are often recommended in critically ill patients when gastrointestinal tract function is intact. Conventional methods of placement include turning the patient on the right side and the use of drugs that stimulate peristalsis to promote transpyloric passage. A prospective study was initially performed to assess the success of conventional methods used to promote transpyloric feeding tube placement in patients requiring assisted ventilation admitted to the Surgical Intensive Care Unit (SICU) (Part I of the study). In 68 critically ill ventilated patients, placement of nasoduodenal feeding tubes was attempted. Successful transpyloric placement was achieved in only ten patients. There was no correlation between age, gender, admitting diagnosis, time of tube placement and successful placement. The second part of the study was initiated to assess the safety of nasogastric feeding in critically ill ventilated patients. Forty-two patients admitted to the SICU were considered candidates for gastrointestinal tract feeding and were fed through the gastric route. Twenty-five patients reached enteral feeding goal rate within 72 hours, while 34 patients achieved goal rate by five days. Eight patients required total parenteral nutrition to meet nutritional needs because of an inability to achieve adequate nutritional support enterally. There were 11 complications noted in ten patients, including one episode of aspiration pneumonia. The presence of complications was not related to age, gender, admitting diagnosis, infusion method or type of formula used. Duodenal intubation using conventional methods in critically ill ventilated patients is unsuccessful in most patients. Nasogastric feeding in this group of patients can be safely administered in selected instances.