Practice of Tumor Bed Boost in Patients after Oncoplastic Breast-Conserving Surgery

The practice of boost to the tumor bed after treatment with oncoplastic breast-conserving surgery (BCS) remains variable. Using a survey, the present study evaluated the current practice of tumor bed boost administered in women after oncoplastic BCS. Actively practicing radiation oncologists across India were sent a questionnaire on the practice of adjuvant whole-breast radiotherapy and tumor bed boost after oncoplastic BCS via email and encouraged to participate. Of the 54 radiation oncologists who participated, most (98.1%) used a linear accelerator for radiotherapy. Hypofractionation was preferred by 59.26%, standard fractionation by 7.41%, and the remaining selected the fractionation strategy based on various patient factors. In addition, 83.33% participants reported that they always planned tumor boost, 51.85% preferred photons for the boost, and 75.93% administered sequential boost. The most common dose for the boost was 12.5 Gy in five fractions (40.74%). Most participants (77.78%) revealed that they used a combination of methods for identifying the tumor bed. With respect to clip placement, most surgeons (96%) at the participants' centers placed ≥ 4 clips at the tumor site, with both the base and margins being preferred by surgeons (81.48%) for placement. Finally, 12.96% participants revealed that the surgeons always involved them during surgical planning, whereas 7.4% participants reported that they always included the surgeons during radiotherapy planning, suggesting that radiation oncologists and oncoplastic surgeons do not involve each other during surgical and radiotherapy planning, possibly leading to suboptimal treatment. This may be attributed to the absence of guidelines regarding boost practices after oncoplastic BCS.

Extramedullary plasmacytoma of the larynx - Case report

Extramedullary plasmacytoma of the larynx is an extremely rare entity accounting for 0.04-0.45% of malignant tumours of the larynx. The objective of this clinical case report is to highlight the diagnosis and management of a unique case such as this. A 77-year-old gentleman presented with complaints of hoarseness for 1 year. Computed tomography image revealed a soft tissue mass lesion involving the right true vocal cord. Direct laryngoscopic biopsy was performed and subjected to histopathological examination, which showed collection of plasma cells. Immunohistochemistry confirmed the presence of Kappa and Lambda cells. Multiple myeloma (MM) was ruled out. The patient received radical intent radiation therapy using 3DCRT technique with a dose of 50Gy in 25# over 5 weeks. He experienced improvement in hoarseness on subsequent follow-up visits. At 1-year follow up, positron emission tomography computed tomography showed near total resolution of disease with no progression to MM. Radiation therapy alone is known to achieve good local control, recurrence free survival, and organ preservation in such cases.

Abstract P1-08-06: Oncology nursing in India: are we up to speed?

Background: Cancer management is a critical component of healthcare worldwide. Improvement in cancer care has improved the longevity of patients, and they require continued care from healthcare workers, including nurses. Although nurses in India are trained to care for patients in general, courses dedicated to cancer care are few. The present study evaluated the knowledge of nurses involved in cancer management via an online survey. Materials and methods: A survey pertaining to nursing practices in cancer management was distributed electronically to nurses in India from January to April 2022. The survey was designed to evaluate treatment-specific knowledge and confidence of the nurses in managing patients with cancer. The data received was analyzed using Microsoft Excel 2016. The responses were divided into two groups: responses marked 4 and 5 on the scale were grouped as confident responses, whereas those marked 1, 2, and 3 were grouped as unconfident responses. Chi-squared analyses were performed using the OpenEpi online tool. Results: A total of 422 nurses replied to the questionnaire; of these, 399 (94.55%) said that they have experience in caring for patients with cancer. Of the 399, 198 (49.62%) worked in specialized cancer care centers and the remaining 201 (50.38%) worked in general hospitals. Nearly two-third of the nurses (n = 262; 65.7%) replied that they studied cancer care as a part of their nursing curriculum, whereas the remaining learnt through personal experience. A total of 335 (84%) nurses had undergone a specialized course in chemotherapy management, and most were confident about their knowledge on chemotherapy administration, central line management, and side effect and precaution management. Only 41 (10.3%) had undergone a specialized course in oncology-directed surgical management; yet based on their primary nursing training more than half of the nurses were confident of performing pre- and postoperative management. With respect to a more specialized surgical care, only 144 (36.1%) were confident in providing stoma care and 181 (45.4%) were confident in teaching preventive lymphedema care after surgery. Although a majority had completed a specialized course in post-radiation management (n = 255; 93.2%), only half were confident in identifying skin-induced changes and providing care for patients receiving radiotherapy. Furthermore, only half of the nurses were aware of the role of nursing staff in brachytherapy (n = 200; 50.1%). Most nurses did not undergo any specialized course (n = 360; 90.2%) in palliative management; 124 (31.1%) nurses said that they were not very confident in adequately counselling patient relatives with regard to symptomatic treatment. Nurses working in specialized cancer centers (n = 198) were significantly more confident in administering and managing central lines for chemotherapy; performing adequate chemotherapy drug disposal; and assessing the needs of cancer patients and their family members than their counterparts working in general hospitals (n = 201) (all p < 0.05). Only 54.4% of the respondents were aware of oncology-directed nursing programs available in the country, and only half were able to access them (n = 160; 55.2%) owing to the lack of guidance (n = 130; 32.58%), time (n = 93; 23.31%), and funds (n = 46; 11.53%). Hence, when asked whether they would be inclined to attend a hybrid course, majority (n = 349; 87.47%) indicated in the affirmative. Also, 338 (84.7%) nurses replied that they would be inclined to participate in cancer screening programs after pursuing such a specialized course. Conclusions: The results of this study highlight the lacunae in nurses’ oncology training. Thus, there is an obvious need to redesign the existing oncology-directed nursing programs to include palliative care and organ-site specific care. Designing these courses in the hybrid format may improve its accessibility and the willingness of nurses to attend.

Citation Format: Garvit Chitkara, Sridevi Murali-Nanavati, Nikhil Bardeskar, Ajinkya Gupte, Shruti Behal, Mugdha Lad, Prajakta Dongarkar, Muzammil Shaikh, Kaustav Talapatra. Oncology nursing in India: are we up to speed? [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P1-08-06.

A scoping review of interventions to mitigate common non-communicable diseases among people with TB

BACKGROUND: Recommendations have been made to integrate screening for common non-communicable diseases (NCDs) within TB programs. However, we must ensure screening is tied to evidence-based interventions before scale-up. We aimed to map the existing evidence regarding interventions that address NCDs that most commonly affect people with TB.METHODS: We systematically searched PubMed, Medline, and Embase for studies that evaluated interventions to mitigate respiratory disease, cardiovascular disease, alcohol and substance use disorder, and mental health disorders among people with TB. We excluded studies that only screened for comorbidity but resulted in no further intervention. We also excluded studies focusing on smoking cessation interventions for which evidence-based guidelines are well established.RESULTS: The search identified 20 studies that met our inclusion criteria. The most commonly evaluated intervention was referral for diabetes care (6 studies). Other interventions included pulmonary rehabilitation (5 studies), care programs for alcohol use disorder (4 studies), and psychosocial support or individual counselling (5 studies).CONCLUSION: There is limited robust evidence to support identified interventions in changing individual outcomes, and a significant knowledge gap remains on the long-term durability of the interventions´ clinical benefit, reach, and effectiveness. Implementation research demonstrating feasibility and effectiveness is needed before scaling up.

Concomitant pulmonary disease is common among patients with extrapulmonary TB

BACKGROUND :

Microbiologic screening of extrapulmonary TB (EPTB) patients could inform recommendations for aerosol precautions and close contact prophylaxis. However, this is currently not routinely recommended in India. Therefore, we estimated the proportion of Indian patients with EPTB with microbiologic evidence of pulmonary TB (PTB).

METHODS :

We characterized baseline clinical, radiological and sputum microbiologic data of 885 adult and pediatric TB patients in Chennai and Pune, India, between March 2014 and November 2018.

RESULTS :

Of 277 patients with EPTB, enhanced screening led to the identification of 124 (45%) with concomitant PTB, including 53 (19%) who reported a cough >2 weeks; 158 (63%) had an abnormal CXR and 51 (19%) had a positive sputum for TB. Of 70 participants with a normal CXR and without any cough, 14 (20%) had a positive sputum for TB. Overall, the incremental yield of enhanced screening of patients with EPTB to identify concomitant PTB disease was 14% (95% CI 12–16).

CONCLUSIONS :

A high proportion of patients classified as EPTB in India have concomitant PTB. Our results support the need for improved symptom and CXR screening, and recommends routine sputum TB microbiology screening of all Indian patients with EPTB.

Dosimetric Comparison of Four Different Radiotherapy Planning Techniques for Adjuvant Radiotherapy of Left-Sided Breast, Axilla, and Supraclavicular Fossa

Purpose/Aim:

Forward planned intensity-modulated radiotherapy (forward IMRT) with breath-hold (BH) technique is considered optimal by most practitioners for treating left-sided breast cancer. Regional nodal irradiation including axilla and supraclavicular fossa (SCF) increases can increase dose-to-organs at risk (OAR) especially lung. This study was done to assess the potential of inverse planned IMRT (inverse IMRT) to achieve significant reduction in dose to OAR.

Materials and Methods:

Ten patients with left-sided breast cancer treated with Active Breath Co-ordinator BH technique were included in the study. Forward IMRT plans were generated in both BH and free breathing (FB) scans. Inverse IMRT plans were generated in FB scan using Tomotherapy-Direct and Tomotherapy-Helical techniques. Contouring was done as per the ESTRO consensus contouring guidelines. The dose prescribed was 40 Gy in 15 fractions. Statistical significance was tested using one-way ANOVA for parametric data and Kruskall–Wallis test for nonparametric data. Multiple comparison tests were done by using Bonferroni test. P <0.05 was considered to denote statistical significance.

Results:

Inverse IMRT plans achieved superior homogeneity index compared to forward IMRT with BH. Tomotherapy-Direct reduced dose to ipsilateral lung, compared to the forward IMRT with BH while achieving similar doses to other OAR. Tomotherapy-Helical plans achieved significantly better conformity index and reduced maximum dose to left anterior descending artery compared to forward IMRT plans, but low dose to other OAR was significantly worse.

Conclusion:

For left-sided breast, axilla, and SCF radiotherapy, inverse IMRT with Tomotherapy-Direct plan achieved better homogeneity index and reduced dose to ipsilateral lung compared to forward IMRT with BH.

Hepatocellular carcinoma patients with portal vein thrombosis treated with robotic radiosurgery: Interim results of a prospective study

BACKGROUND

This is a prospective study evaluating the role of stereotactic body radiotherapy (SBRT) with CyberKnife (CK) in Indian patients suffering from hepatocellular carcinoma with portal vein thrombosis (HCC-PVT).

METHODS

Patients with inoperable HCC-PVT, good performance score (PS), and liver function are accrued for treatment on CK (version M6) and planned with Multiplan (iDMS V2.0). Triple-phase contrast computed tomography (CT) scan was done for contouring, and the gross tumor volume (GTV) included contrast-enhancing mass within main portal vein and adjacent parenchymal disease. Dose prescription was as per-risk stratification protocol (22-50 Gy in 5 fractions) while achieving the constraints of mean liver dose <15 Gy, 800 cc liver <8 Gy, and the duodenum max of ≤24 Gy).

RESULTS

Seventy-two HCC-PVT accrued till date (mean age 63 years [38-76 years], 96% male; Child-Pugh [CP] A 84%, B 9%; Barcelona-Clinic Liver Cancer [BCLC] C 96%; PS0-1: 80%, Karnofsky performance score [KPS]>70: 88%; co-morbidities 42%; infective 12%, alcohol intake 31%, adjuvant sorafenib 39%). CP scores 5, 6, 7, and 8 were in 35%, 32%, 8%, and 18%, respectively. Focal disease with portal vein thrombus (PVT) in 21%, liver involvement >50% and <50% in 46% and 32%. Liver cancer study group of Japan staging-based portal vein invasion VP2, VP3, and VP4 in 22%, 29%, and 40%. Cancer of the Liver Italian Programm (CLIP) scores 1, 2, 3, 4, and 5 were in 8%, 26%, 31%, 26%, and 7%, respectively. Mean follow-up was 7.3 months (median 6 months, standard deviation [SD] 6; range 3-30 months). Mean actuarial overall survival (OS) was 11.4 months (SE 1.587; 95% CI: 8-14.2 months). Six months and 12 months actuarial OS 55% and 38%, respectively. At last follow-up, 25/69 (36%) were alive and 44/69 (64%) were dead. Among 54 patients evaluated for response assessment, 23 (30%) had radiological confirmed PVT response, 1 (3%) had response of IVC thrombus, and 30 (42%) had no or minimal response to SBRT. Actuarial OS in responders and non-responders were 14.4 months (95% CI 9.4-19.2) and 7.4 months (95% CI 4.9-9.7), p-value: 0.022. Six and 12 months survival in responders and non-responders were 65.7% and 37% and 49% and 24.6%, respectively. Post-SBRT, 4 (12%) patients underwent transarterial chemoembolization (TACE) 3 patients (8%) and 1 patient (4%) transarterial radioembolization (TARE). Post-CK, (<4 weeks) 2 patients (4%) had decompensation.

CONCLUSIONS

PVT response or recanalization after SBRT is a statistically significant prognostic factor for survival function in HCC-PVT.

Diabetes and pre-diabetes among household contacts of tuberculosis patients in India: is it time to screen them all?

SETTING

Pre-diabetes mellitus (pre-DM) and DM increase the risk of developing tuberculosis (TB). Screening contacts of TB patients for pre-DM/DM and linking them to care may mitigate the risk of developing TB and improve DM management.

OBJECTIVE

To measure the prevalence of pre-DM/DM and associated factors among the adult household contacts (HHCs) of pulmonary TB patients.

METHODS

Between August 2014 and May 2017, adult HHCs of newly diagnosed adult PTB patients in Pune and Chennai, India, had single blood samples tested for glycosylated haemoglobin (HbA1c) at enrolment. DM was defined as previously diagnosed, self-reported DM or HbA1c 6.5%, and pre-DM as HbA1c between 5.7% and 6.4%. Latent tuberculous infection (LTBI) was defined as a positive tuberculin skin test (5 mm induration) or QuantiFERON® Gold In-Tube (0.35 international units/ml).

RESULTS

Of 652 adult HHCs, 175 (27%) had pre-DM and 64 (10%) had DM. Forty (64%) HHCs were newly diagnosed with DM and 48 (75%) had poor glycaemic control (HbA1c 7.0%). Sixty-eight (22%) pre-DM cases were aged 18-34 years. Age 35 years, body mass index 25 kg/m2, chronic disease and current tobacco smoking were significantly associated with DM among HHCs.

CONCLUSIONS

Adult HHCs of TB patients in India have a high prevalence of undiagnosed DM, pre-DM and LTBI, putting them at high risk for developing TB. Routine DM screening should be considered among all adult HHCs of TB.

Prevalence of dysglycemia and clinical presentation of pulmonary tuberculosis in Western India

SETTING

Pune, India.

OBJECTIVES

To estimate the prevalence and risk factors of pre-diabetes mellitus (DM) and DM, and its associations with the clinical presentation of tuberculosis (TB).

DESIGN

Screening for DM was conducted among adults (age  18 years) with confirmed TB between December 2013 and January 2017. We used multinomial regression to evaluate the risk factors for pre-DM (glycated hemoglobin [HbA1c]  5.7-6.5% or fasting glucose 100-125 mg/dl) and DM (HbA1c  6.5% or fasting glucose  126 mg/dl or random blood glucose > 200 mg/dl or self-reported DM history/treatment) and the association of dysglycemia with the severity of TB disease.

RESULTS

Among 1793 participants screened, 890 (50%) had microbiologically confirmed TB. Of these, 33% had pre-DM and 18% had DM; 41% were newly diagnosed. The median HbA1c level among newly diagnosed DM was 7.0% vs. 10.3% among known DM (P < 0.001). DM (adjusted OR [aOR] 4.94, 95%CI 2.33-10.48) and each per cent increase in HbA1c (aOR 1.42, 95%CI 1.01-2.01) was associated with >1+ smear grade or 9 days to TB detection.

CONCLUSION

Over half of newly diagnosed TB patients had DM or pre-DM. DM and increasing dysglycemia was associated with higher bacterial burden at TB diagnosis, potentially indicating a higher risk of TB transmission to close contacts.

Novel interferon-gamma assays for diagnosing tuberculosis in young children in India

SETTING

The tuberculin skin test (TST) and interferon-gamma release assays (IGRAs) are used as supportive evidence to diagnose active tuberculosis (TB). Novel IGRAs could improve diagnosis, but data are lacking in young children.

DESIGN

Children (age 5 years) with suspected TB were prospectively screened at a tertiary hospital in Pune, India; the children underwent TST, and standard (early secretory antigenic target 6 and culture filtrate protein 10) and enhanced (five additional novel antigens) enzyme-linked immunospot (ELISpot) assays.

RESULTS

Of 313 children (median age 30 months) enrolled, 92% had received bacille Calmette-Guérin vaccination, 53% were malnourished and 9% were coinfected with the human immunodeficiency virus (HIV); 48 (15%) had TB, 128 (41%) did not, and TB could not be ruled out in 137 (44%). The sensitivity of enhanced (45%) and standard (42%) ELISpot assays for diagnosing TB was better than that of TST (20%) (P  0.03); however, enhanced ELISpot was not more sensitive than the standard ELISpot assay (P = 0.50). The specificity of enhanced ELISpot, standard ELISpot and TST was respectively 82% (95%CI 74-89), 88% (95%CI 81-94) and 98% (95%CI 93-100). Rv3879c and Rv3615c, previously reported to be promising antigens, failed to improve the diagnostic performance of the ELISpot assay.

CONCLUSION

The TST and the standard and novel ELISpot assays performed poorly in diagnosing active TB among young children in India.

Histopathologic resolution of adult liver transplantation adenovirus hepatitis with cidofovir and intravenous immunoglobulin: a case report

Adenovirus (ADV) infections in adult solid organ transplant recipients, although rare, are associated with high mortality. There are no randomized controlled trials establishing the efficacy of specific treatment modalities. To our knowledge apparent response to treatment with combination therapy with intravenous cidofovir (CDV) and immunoglobulin (IVIG) has only been demonstrated in 2 adult renal transplant recipients in whom ADV was documented in body fluids only. We describe an adult liver transplant recipient diagnosed with ADV hepatitis based on positive immunohistochemical staining of a liver biopsy specimen, positive blood ADV DNA polymerase chain reaction (PCR), and treated with the combination of CDV and IVIG. We demonstrated both clearance of viremia and histopathologic resolution of the hepatitis despite the patient's fatal outcome. To our knowledge this is the only case documenting eradication of tissue-invasive ADV disease in any solid organ transplant recipient using CDV and IVIG. This case provides evidence to support the use of this drug combination, which has many potential toxicities that might discourage its use otherwise.

Epidemiology of capsular and surface polysaccharide in Staphylococcus aureus infections complicated by bacteraemia

Staphylococcus aureus is a leading cause of serious hospital- and community-acquired infections. The discovery of serologically distinct capsular polysaccharides on the surface of clinical isolates has allowed the development of vaccines and passive protective immunity. We have studied patient characteristics, infection characteristics and the surface and capsular polysaccharide serotype distribution in patients with S. aureus infections complicated by bacteraemia admitted to VA hospitals in Maryland between 1995 and 2000. Nine hundred and ninety-three blood cultures from 331 patients were positive for S. aureus. Thirty-eight percent of patients had diabetes, 11% had end-stage renal failure, and 23% were injection drug users. Forty-two percent of infections were caused by methicillin-resistant strains (MRSA), and 60% were acquired during hospitalization. Serotyping of the first available isolate per patient (N=234 isolates) using polyclonal antibodies showed three major phenotypes--42%, type 8 (T8) capsule; 50%, type 5 (T5) capsule; and 8%, 336 polysaccharide. MRSA isolates were significantly more likely to be T5 than methicillin-susceptible isolates (66% vs. 39%, P<0.001). The proportion of T5 MRSA increased significantly (years 1-2: 41%; years 3-4: 65%; years 5-6: 90%, P<0.001). This large sample of patients with serious S. aureus infection confirms that capsular polysaccharides T5 and T8 cause most human infections, and together with serotype 336, account for nearly all those with bacteraemia.

Salmonella spp. are affected by different levels of water activity in closed microcosms

Controlling water activity (a(w)) can significantly impact the growth of Salmonella in poultry litter and manure - a phenomenon that was studied quantitatively using two common serotypes of Salmonella. The quantitative effect of changes in levels of a(w) on Salmonella populations was determined using inoculated, frosted glass rectangles placed in closed chambers (microcosms). Glass rectangles with known concentrations of Salmonella enteritidis and S. brandenburg were placed in microcosms maintained at an a(w) level of 0.893 for 24 h at room temperature (RT) and then transferred to other microcosms maintained at the same temperature but with higher a(w) levels (0.932 and 0.987). Salmonella populations on the slides were quantified at 4, 18, 24, and 48 h. Slightly elevated levels of a(w) (<0.1, i.e., 10% equilibrium relative humidity) for 24 h resulted in a 100-fold increase in counts of Salmonella. The data also suggested that in vitro adaptation to dry environments may occur when the organisms are exposed to alternating levels of relatively high and low (0.987 and 0.893) levels of a(w). Any increased tolerance of Salmonella to reduced levels of a(w) could be the result of physico-chemical changes in the organism due to selective environmental pressure, formation of a protective biofilm, and/or entry into a dormant state. Results from this study are compatible with those from previously reported on-farm surveys, reinforcing the contention that maintaining a(w) below 0.85 in and around litter/manure surfaces in poultry or livestock bedding areas may be a critical factor in safe production of food.

Stabilization of alginate beads using radiation polymerized polyacrylamide

A technique has been described for the stabilization of calcium alginate beads using radiation polymerized acrylamide. The technique involved dropping a mixture containing the cells (20%), sodium alginate (2%), acrylamide (2.5%) and N-N'-methylene-bis-acrylamide (0.1%) through a syringe needle into cold (-75 degrees C) toluene. The frozen beads obtained were exposed to 60Co gamma-rays (0.5 KGy) and were then thawed in 0.1 M CaCl2 solution. Unlike the calcium alginate beads the conjugate beads were not found to be dissolved when incubated in 3% trisodium citrate solution. Stabilized beads containing entrapped yeast cells could be reused for over 15 batches for the inversion of sucrose without loss in activity or chemical integrity of the beads.

Risk prediction charts for low birth weight

OBJECTIVE

To develop intrauterine fetal growth monitoring charts for prediction of babies with low birth weight (LBW).

DESIGN

Prospective study.

SETTING

Antenastal clinic of a government and a private hospital.

SUBJECTS

Two hundred and eighty one healthy pregnant women were enrolled before 28 weeks of pregnancy.

MAIN OUTCOME MEASURES

The uterine fundal height and abdominal girth were recorded fortnightly. Following delivery, the neonatal birth weight was correlated with these measurements.

RESULTS

Graphs were plotted for the mean fundal height and abdominal girth in relation to gestational age for neonatal weight categories of 2000 g, 2500 g and 3000 +/- 200 g. Measurement of the fundal height and abdominal girth predicted the neonatal weight category with a sensitivity of 87.5%, specificity of 90% and positive predictive value of 77.8%.

CONCLUSIONS

The uterine fundal height and abdominal girth, when related to the gestational age, can accurately predict the neonatal birth weight category. The charts prepared in this study can help in prediction of LBW babies and allow appropriate intervention to be undertaken in the antenatal period at grass root level.

Block copolymer microdomains: a novel medium for enzymatic reactions

Block copolymers exhibit the phenomenon of microdomain formation in pure states as well as in solutions. The microdomains vest the block copolymer assemblies with the intriguing characteristics of microheterogeneous media. We demonstrate that this microheterogeneity in hydrophobic-hydrophilic block copolymer systems can be exploited for immobilizing enzymes and to carry out enzymatic reactions. Examples involving cholesterol oxidase and horseradish peroxidase are provided here. The observed changes in the enzymatic activity in block copolymer microdomains from that in the aqueous media are interpreted in terms of the hydrophobicity of the reaction microenvironment. The block copolymer microdomains are simple to generate, well defined, and easily reproducible. Therefore, they hold significant potential as media for enzymatic biosynthetic reactions when the substrates or the reaction products are water insoluble.

Effects of flow on the synthesis and release of fibronectin by endothelial cells

Human umbilical vein endothelial cells at confluence were subjected to steady shear flow. The effect of flow on the synthesis of fibronectin, its release into the medium, and incorporation into the extracellular matrix were investigated. The total content of fibronectin in endothelial cells exposed to flow was found to be lower than that in static controls after periods of 12 to 48 h. In the presence of cycloheximide there was no difference in the fibronectin content of sheared and unsheared cells. Our results suggest that the synthesis of fibronectin is inhibited by the flow-induced perturbation of endothelial cells.