Exceptional response to cetuximab monotherapy after failure of immunotherapy with a checkpoint inhibitor in a patient with metastatic head and neck squamous cell cancer: case report and review of the literature.

Immunotherapy with PD-1 inhibitors monotherapy or combined with chemotherapy comprises the first-line palliative treatment for patients with recurrent or metastatic head and neck squamous cell cancers (R/M HNSCC). The established survival advantage among responders is overshadowed by the high percentage of patients failing the standard PD-1 inhibitor-based treatments. Salvage therapies are direly needed. However, no current standards are available. We present the case of a 65-year-old patient with heavily pretreated laryngeal squamous cell carcinoma who had an exceptional response to cetuximab monotherapy following the failure of immunotherapy with the PD-1 inhibitor nivolumab. We reviewed the literature for other cases of exceptional response to cetuximab, clinical studies investigating the combined or sequential administration of cetuximab and PD-1 inhibitors, and the mechanistic rationale for consideration of cetuximab as a potential salvage treatment after immunotherapy with PD-1 inhibitors. In addition to the specific epidermal growth factor receptor inhibitory effect, cetuximab, as an immunoglobulin G1 isotype, binds NK cells and elicits antibody-dependent cellular toxicity, triggering a domino of immunostimulatory, and immunoinhibitory effects that actually might decrease the cetuximab anticancer efficacy. However, in a tumor microenvironment exposed to previous treatment with a PD-1 inhibitor, the effects of the PD-1 inhibitor followed by cetuximab on innate and adaptative immune response appear to synergize. Specifically, persistent immune checkpoint inhibitors' consequences may negate downstream immunosuppressive effects of cetuximab caused through PD-1/PD-L1 upregulation, making it a more potent treatment option. Besides the potential synergistic effect on antitumor immune response with previous immune checkpoint inhibitors therapy, cetuximab is the only targeted agent approved for treating R/M HNSCC, making it a most advantageous candidate for further treatment validation studies as salvage treatment post-immunotherapy.

Y-Chromosome-Linked Genes Are Associated With Sex-Related Head-Neck Squamous Cell Carcinoma Survival.

OBJECTIVE: To define novel gene biomarkers for prognosis of head and neck squamous cell carcinoma (HNSCC) patients' survival. STUDY DESIGN: Retrospective study. SETTING: The Cancer Genome Atlas (TCGA) HNSCC RNA-Seq dataset. METHODS: Coexpressed gene clusters were extracted from TCGA RNA-seq data using our previously published method (EPIG). Kaplan-Meier estimator was then used for overall survival-relevant analysis, with patients partitioned into 3 groups based on gene expression levels: female, male_low, and male_high. RESULTS: Male had better overall survival than female and male with higher expression level of Y-chromosome-linked (Y-linked) genes had significantly better survival than those with lower expression levels. In addition, male with a higher expression level of Y-linked genes showed even better survival when they have a higher level of coexpressed cluster of genes related to B or T cell immune response. Other clinical conditions related to immune responses also consistently showed favorable effects on the Y-linked genes for survival estimation. Male patients with higher expression level of Y-linked genes also have significantly higher tumor/normal tissue (T/N) ratio of those genes and higher level of several immune responses related clinical measurements (eg, lymphocyte and TCR related). Male patients with lower expression level of Y-linked genes benefited from radiation-only treatment. CONCLUSIONS: The favorable role of a cluster of coexpressed Y-linked genes in HNSCC patients' survival is potentially associated with elevated level of immune responses. These Y-linked genes could serve as useful prognostic biomarkers for HNSCC patients' survival estimation and treatment.

Intensity-modulated radiotherapy with planned Gamma Knife radiosurgery boost for head and neck cancer with extensive disease in proximity to critical structures.

BACKGROUND: To describe intensity-modulated radiotherapy (IMRT) with Gamma Knife Radiosurgery (GKRS) boost for locally advanced head and neck cancer (HNC) with disease near dose-limiting structures. METHODS: Patients with HNC treated with IMRT/GKRS as part of a combined modality approach between 2011 and 2021 were reviewed. Local control, overall survival and disease-specific survival were estimated using the Kaplan Meier method. RESULTS: Twenty patients were included. Nineteen patients had T3-4 tumors. Median follow-up was 26.3 months. GKRS site control was 95%. Two patients progressed at the treated primary site, one patient failed at the edge of the GKRS treatment volume, with no perineural or intracranial failure. 2-year OS was 94.7% (95% CI: 85.2%-100%). Concurrent chemotherapy was given in nine patients (45%). One patient (5%) received induction/concurrent chemotherapy. Brain radionecrosis occurred in three patients, one of which was biopsy-proven. CONCLUSIONS: IMRT plus GKRS boost results in excellent disease control near critical structures with minimal toxicity.

Early [18]FDG PET/CT scan predicts tumor response in head and neck squamous cell cancer patients treated with erlotinib adjusted per smoking status.

Translational Relevance: Evaluation of targeted therapies is urgently needed for the majority of patients with metastatic/recurrent head and neck squamous cell carcinoma (HNSCC) who progress after immunochemotherapy. Erlotinib, a targeted inhibitor of epidermal growth factor receptor pathway, lacks FDA approval in HNSCC due to inadequate tumor response. This study identifies two potential avenues to improve tumor response to erlotinib among patients with HNSCC. For the first time, this study shows that an increased erlotinib dose of 300 mg in smokers is well-tolerated and produces similar plasma drug concentration as the regular dose of 150 mg in non-smokers, with increased study-specific defined tumor response. The study also highlights the opportunity for improved patient selection for erlotinib treatment by demonstrating that early in-treatment [18]FDG PET/CT is a potential predictor of tumor response, with robust statistical correlations between metabolic changes on early in-treatment PET (4-7 days through treatment) and anatomic response measured by end-of-treatment CT. Purpose: Patients with advanced HNSCC failing immunochemotherapy have no standard treatment options. Accelerating the investigation of targeted drug therapies is imperative. Treatment with erlotinib produced low response rates in HNSCC. This study investigates the possibility of improved treatment response through patient smoking status-based erlotinib dose optimization, and through early in-treatment [18]FDG PET evaluation to differentiate responders from non-responders. Experimental design: In this window-of-opportunity study, patients with operable HNSCC received neoadjuvant erlotinib with dose determined by smoking status: 150 mg (E150) for non-smokers and 300 mg (E300) for active smokers. Plasma erlotinib levels were measured using mass spectrometry. Patients underwent PET/CT before treatment, between days 4-7 of treatment, and before surgery (post-treatment). Response was measured by diagnostic CT and was defined as decrease in maximum tumor diameter by ≥ 20% (responders), 10-19% (minimum-responders), and < 10% (non-responders). Results: Nineteen patients completed treatment, ten of whom were smokers. There were eleven responders, five minimum-responders, and three non-responders. Tumor response and plasma erlotinib levels were similar between the E150 and E300 patient groups. The percentage change on early PET/CT and post-treatment PET/CT compared to pre-treatment PET/CT were significantly correlated with the radiologic response on post-treatment CTs: R=0.63, p=0.0041 and R=0.71, p=0.00094, respectively. Conclusion: This pilot study suggests that early in-treatment PET/CT can predict response to erlotinib, and treatment with erlotinib dose adjusted according to smoking status is well-tolerated and may improve treatment response in HNSCC. These findings could help optimize erlotinib treatment in HNSCC and should be further investigated. Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT00601913, identifier NCT00601913.

Oropharyngeal Carcinoma Treated with Surgery Alone: Outcomes and Predictors of Failure.

OBJECTIVE: To analyze the oncologic outcomes and risk factors for recurrence in patients who underwent surgery for oropharyngeal squamous cell carcinoma (OPSCC), and in whom adjuvant therapy was not recommended or was declined. METHODS: Retrospective cohort study of patients with OPSCC who were treated with transoral surgery only at a tertiary care academic medical center from April 2010 to March 2019. RESULTS: Seventy-four patients met inclusion criteria. In 16, adjuvant therapy was recommended but declined. There were 8 recurrences, of which 6 had been given recommendations for adjuvant therapy. Of the 8 recurrences, 2 died, 2 are alive with disease, and 4 were successfully salvaged. Five patients died of unrelated causes. Lymphovascular invasion (LVI, P = .016) had a significant impact on recurrence, while other pathologic features of the primary tumor such as size, location, human papillomavirus (HPV) status, and margin status did not. Margins were classified as "positive" in 4 patients, "close" in 54, and "negative" in 16. There were 3 local recurrences (4.1%), each of whom had declined adjuvant therapy. Lymph node features such as N-stage (P = .0004), number of positive nodes (P = .0005), and presence of extra-nodal extension (ENE, P = .0042) had a statistically significant impact on relapse. Smoking history and surgical approach showed no significant impact on recurrence. CONCLUSION: Patients who undergo surgery for HPV-positive OPSCC with negative margins, no PNI, no LVI, and ≤1 positive lymph node without ENE have low risk for recurrence. These patients can likely be safely treated with surgery alone. Patients with these risk factors who decline adjuvant therapy are at risk for recurrence, and should be monitored.

Comprehensive gene cluster analysis of head and neck squamous cell carcinoma TCGA RNA-seq data defines B cell immunity-related genes as a robust survival predictor.

BACKGROUND: The authors aimed to define novel gene expression signatures that are associated with patients' survival with head and neck squamous cell carcinoma (HNSCC). METHODS: TCGA RNA-seq data were used for gene expression clusters extraction from 499 tumor samples by the "EPIG" method. Tumor samples were then partitioned into lower and higher than median level groups for survival relevant analysis by Kaplan-Meier estimator. RESULTS: We found that two gene clusters (_1, _2) are favorably, while two (_3, _4) are unfavorably, associated with patients' survival with HNSCC. Notably, most genes on the top lists of cluster_2 are associated with B cells. A gene expression signature with combined genes from cluster_2 and _4 was further determined to be associated with HNSCC survival rate. CONCLUSION: Our work strongly supported a favorable role of B cells in patients' survival with HNSCC and identified a novel coexpressed gene signature as prognostic biomarker for patients' survival with HNSCC estimation.

Impact of outcomes data on the management of postoperative hypocalcemia in head and neck endocrine surgery patients.

Postoperative hypocalcemia is a well-described outcome following thyroid and parathyroid surgery with symptoms ranging from clinically insignificant laboratory findings to tetany and seizures. The aims of this study were 1. To identify the characteristics and management patterns of postoperative hypocalcemia in head and neck endocrine surgery patients and 2. To compare outcomes between patients treated with empiric calcium and patients treated using a biochemically driven calcium replacement algorithm. Clinical electronic medical record (EMR) data was collected from patients who had undergone total thyroidectomy, completion thyroidectomy, and/or parathyroidectomy at Wake Forest Baptist Medical Center (WFBMC), a tertiary referral and academic institution. Between July 1, 2016, and June 30, 2017, 298 adult patients underwent surgery by a WFBMC Head & Neck (H&N) endocrine surgeon. Objective calcium and parathyroid hormone levels, postoperative supplementation with calcium and Vitamin D, 30-day physician access line (PAL) phone call utilization, emergency department (ED) encounters, and readmission rates were queried. The overall rate of hypocalcemia was 17.4%. No statistically significant difference in PAL utilization, ED visits, or readmissions was found between the empiric supplementation group and those whose supplementation was biochemically directed (PAL 5.0% vs. 5.0% [p = 0.983], ED visit 3.3% vs. 2.5% [p = 0.744], Readmission 1.7% vs. 0% [p = 0.276]). The overall postoperative rates of hypocalcemia and hypoparathyroidism following H&N endocrine surgery were consistent with the reported literature. Neither method of calcium supplementation was superior in reducing PAL utilization, ED encounters, or readmission.

Surgical management of Eagle syndrome: A 17-year experience with open and transoral robotic styloidectomy.

Eagle Syndrome (ES) is a rare disorder that can present with symptoms ranging from globus sensation to otalgia that is attributed to an elongated styloid process and/or calcified stylohyoid ligament. No standardized treatment algorithm exists, and although various surgical approaches have been described, data on the use of transoral robotic surgery (TORS) in this population is limited. To investigate the utility of TORS in the treatment of ES, a retrospective review in 19 ES patients was carried out at a single academic, tertiary medical center between 2000 and 2017. Nineteen patients underwent twenty-one styloid resections: 6 performed via TORS and 15 via transcervical approach. Across all patients, 90% reported some degree of lasting improvement in symptoms while 55% reported significant improvement. When TORS was compared to transcervical resection, there was no difference in the subjective rate of "meaningful" (83 vs. 57%) versus rate of "non-meaningful" symptom improvement (17 vs. 43%) (p = 0.35). There was a trend towards less estimated blood loss (EBL), operative time, and post-operative length of stay (LOS) with TORS versus transcervical cases (9.2 mL vs. 30.0 mL, 98 vs. 156 min, and 0.7 vs. 1.2 days); however, these did not reach statistical significance (p = .11, 0.13, and 0.42, respectively). Three patients experienced complications associated with an open approach, as compared to none with TORS. In select patients, TORS styloidectomy is a reasonable surgical alternative to traditional transoral and transcervical techniques as it provides similar symptom improvement, and reduced length of stay, blood loss, and operative time.

MicroRNA Profiling and Target Genes Related to Metastasis of Salivary Adenoid Cystic Carcinoma.

BACKGROUND/AIM: Perineural invasion and distant metastasis lead to a poor prognosis of adenoid cystic carcinoma and there is no effective therapy available. MicroRNAs (miRNAs) are small non-coding RNAs that regulate target gene expression, which can be biomarkers or therapeutic targets for certain cancer types. We aimed to identify miRNAs and their target genes possibly involved in metastasis of salivary gland adenoid cystic carcinoma (SACC). MATERIALS AND METHODS: Using Nanostring nCounter analysis, we examined miRNA expression in two SACC cell lines: SACC-83 and SACC-LM, with low and high lung metastasis rates, respectively. We then verified the differentially expressed miRNAs with real-time polymerase chain reaction in the cell lines and in tumor samples from patients with SACC. miRNA target-gene expression was also analyzed. RESULTS: SACC-83 showed higher gene expression of miR-130a, miR-342, and miR-205; SACC-LM showed higher gene expression of miR-99a and miR-155. In human tissue, miR-205 was highly expressed in the primary SACC, while miR-155 and miR-342 were highly expressed in recurrent SACC. Six predicted target genes of miRNA-155 and miR-99a linked to tumorigenesis were further analyzed and RNA expression of ubiquitin-like modifier activating enzyme 2 (UBA2) was higher in SACC than normal salivary gland tissue, and higher in primary compared to recurrent SACC (p<0.05). RNA expression of retinoic acid receptors (RARS) was higher in tissue from primary than recurrent SACC and normal salivary gland (p<0.05), but that in recurrent SACC was not significantly higher than normal salivary gland tissue. RNA expression of minichromosome maintenance 8 homologous recombination repair factor (MCM8) and 24-dehydrocholesterol reductase (DHCR24) was higher in primary SACC than normal salivary gland tissue (p<0.05). CONCLUSION: miR-99a, miR-155, miR-130a, miR-342, and miR-205 may play a role in metastasis of SACC. MiR-155 may be involved in SACC metastasis through UBA2 pathways, and UBA2 may function as a biomarker/mediator of SACC metastasis.

Chemokine and Chemokine Receptor Profiles in Metastatic Salivary Adenoid Cystic Carcinoma.

AIM: To characterize the chemokine pattern in metastatic salivary adenoid cystic carcinoma (SACC). MATERIALS AND METHODS: Real-time polymerase chain reaction (RT-PCR) was used to compare chemokine and chemokine receptor gene expression in two SACC cell lines: SACC-83 and SACC-LM (lung metastasis). Chemokines and receptor genes were then screened and their expression pattern characterized in human tissue samples of non-recurrent SACC and recurrent SACC with perineural invasion. RESULTS: Expression of chemokine receptors C5AR1, CCR1, CCR3, CCR6, CCR7, CCR9, CCR10, CXCR4, CXCR6, CXCR7, CCRL1 and CCRL2 were higher in SACC-83 compared to SACC-LM. CCRL1, CCBP2, CMKLR1, XCR1 and CXCR2 and 6 chemokine genes (CCL13, CCL27, CXCL14, CMTM1, CMTM2, CKLF) were more highly expressed in tissues of patients without tumor recurrence/perineural invasion compared to those with tumor recurrence. CCRL1 (receptor), CCL27, CMTM1, CMTM2, and CKLF (chemokine) genes were more highly expressed in SACC-83 and human tissues of patients without tumor recurrence/perineural invasion. CONCLUSION: CCRL1, CCL27, CMTM1, CMTM2 and CKLF may play important roles in the development of tumor metastases in SACC.

Tobacco use and surgical outcomes in patients with head and neck cancer.

BACKGROUND: Tobacco use is a risk factor for head and neck cancer, but effects on postoperative outcomes are unclear. METHODS: Patients with head and neck cancer (n = 89) were recruited before surgery. We assessed self-reported tobacco use status (never, former, or current) at study entry and recent tobacco exposure via urinary cotinine on surgery day. Outcomes included hospital length of stay (LOS) and complications. RESULTS: Most participants reported current (32.6%) or former (52.8%) tobacco use; 43.2% were cotinine-positive on surgery day. Complications occurred in 41.6% and mean LOS was 4.0 and 8.8 days in patients who received low and high acuity procedures, respectively. Current and former smokers were over 6 times more likely to have complications than never smokers (p = .03). For high acuity procedures, LOS was increased in current (by 4.4 days) and former smokers (by 2.3 days; p = .02). CONCLUSION: Tobacco use status is associated with postoperative complications and may distinguish at-risk patients.

Increased Expression of MuRF1 Is Associated with Radiation-induced Laryngeal Muscle Atrophy.

BACKGROUND: Laryngeal muscles play an important role in breathing, sound production and trachea protection against food. Laryngeal dysfunctions during radiotherapy for head and neck cancers are common. In the present study, we aimed to investigate the early effect of radiation on the laryngeal muscles in vivo and possible mechanisms involved in this process. MATERIALS AND METHODS: Eight-week-old female C57bl/ mice received neck irradiation with a single dose of 25 Gy and bilateral thyroarytenoid (TA) muscles of mice were collected at day 3, 7 and 10 post-irradiation for evaluating muscle size, myosins, myosin heavy chain (MyHC) composition and MuRF1 protein levels. RESULTS: A significant reduction in the size of muscle fibers and myosins in the TA muscles were observed at days 3, 7, 10 after radiation (p<0.05). The loss of IIB myosin was more severe than that of IIA/X myosins at day 7 post-irradiation (75% vs. 64%). MuRF1 protein level was markedly increased at day 7 and 10 after radiation (p<0.05). CONCLUSION: Radiation induced an acute muscle fiber atrophy and myosin loss in the intrinsic laryngeal muscles. MuRF1 may play an important role in the radiation-induced protein degradation in the laryngeal muscles and warrants further investigation.

The Validity of Self-reported Recent Smoking in Head and Neck Cancer Surgical Patients.

OBJECTIVE: In cancer patients, cigarette smoking causes poorer response to treatment, treatment toxicity, increased risk of recurrence, higher surgical complication rates, and poorer overall survival. As such a significant determinant of patient prognosis, accurate classification of current smoking status is important. Self-reported smoking status may lead to misclassification if patients conceal their true status. The purpose of this study was to assess the validity of self-reported tobacco use during the previous 48 hours in head and neck cancer patients on the day of surgery. STUDY DESIGN: Cross-sectional. SETTING: Two academic medical centers in the southeastern United States. SUBJECTS AND METHODS: On the day of surgery, 108 head and neck cancer patients completed a survey asking about tobacco use during the past 48 hours and had semi-quantitative levels of urinary cotinine measured to biochemically validate self-reported recent smoking. RESULTS: Self-reported smoking yielded a sensitivity of 60.9% (95% CI, 45.4%-74.9%) and a specificity of 98.4% (95% CI, 91.3%-100.0%). The sensitivity increased to 76.1% (95% CI, 61.2%-87.4%) when allowing for the possibility that exposure to secondhand smoke or use of nicotine-containing products could have caused a positive cotinine test. CONCLUSION: In this patient population, self-reported recent smoking yielded a high (39%) proportion of false-negatives, and even 24% remained false-negatives after allowing for other sources of nicotine exposure. This magnitude of underreporting combined with the importance of tobacco use to patient prognosis supports the need for routinely biochemically verifying recent tobacco use in self-reported nonsmokers within the clinical setting.

Polymorphous low-grade adenocarcinoma: a 17 patient case series.

Polymorphous low-grade adenocarcinoma (PLGA) is a rare malignancy most commonly seen in the minor salivary glands. First described in 1983, this entity has been recognized to have an indolent course with rare metastases or deaths. We describe our experience with 17 patients treated at our institution for PLGA from 1984 to 2012. All tumors were located in the oral cavity or soft palate. All patients were treated surgically, with the exception of one patient who declined therapy. No deaths or metastases have been identified in subsequent follow-up. Three patients in this series had undergone prior surgery up to 20 years previously and were treated for recurrences at our institution; no other recurrences have been noted. In summary, PLGA is best treated with wide excision to negative margins with excellent prognosis, but long-term follow-up is recommended given the propensity for late recurrences.

Parathyroid hormone early percent change: an individualized approach to predict postthyroidectomy hypocalcemia.

PURPOSE: The purpose of this study is to evaluate a percent change model of postoperative parathyroid hormone level in thyroidectomy patients as a predictor of hypocalcemia. MATERIALS AND METHODS: Chart review was completed on patients who had undergone total or completion thyroidectomy over a 22-month period in our department. Only those patients with a preoperative ionized calcium and parathyroid hormone (PTH) level and at least 1 postoperative result were included. Ionized calcium levels served as an internal control. The Student t test was used to compare PTH level between the normocalcemic and hypocalcemic groups at each time point. Logistic regression analysis was used to predict hypocalcemia based on the diagnostic criteria. Receiver operator curves were used to maximize sensitivity. RESULTS: Fifty-two patients met the inclusion criteria during the study period. A total of 22 patients (42%) experienced hypocalcemia. We were unable to maximize both sensitivity and specificity at the same time point. When comparing preoperative to 6-hour postoperative PTH percent change, patients with a greater than 44% decrease are likely to have hypocalcemia, with a sensitivity of 100%. Likewise, in those patients without a greater than 44% decrease at 6 hours, early discharge can be considered safe, given the negative predictive value of 100%. CONCLUSION: In our series, patients with a greater than 44% PTH decrease from preoperative to 6-hour postoperative are very likely to develop hypocalcemia. We would propose that these patients need further inpatient monitoring to progress to safe discharge. Likewise, patients with a less than 44% decrease at the 6-hour time point are unlikely to develop hypocalcemia and may be considered safe for discharge.

Topical mithramycin-A modulates submucosal collagen deposition after esophageal burn injury in rats.

OBJECTIVE: To evaluate efficacy of a drug-eluting, dissolvable esophageal (DEDE) stent for the prevention of submucosal collagen deposition in a rat model of acute esophageal injury. SETTING: University laboratory. STUDY DESIGN: Interventional randomized controlled trial. SUBJECTS AND METHODS: Forty two adult, male, age-matched Sprague Dawley rats were randomized to undergo either sham esophageal surgery, esophageal burn injury, or esophageal burn injury and placement of a DEDE stent. All animals underwent open gastrotomy under anesthesia. In group 1, a cautery device was inserted through the gastrotomy into the distal esophagus and removed without creating an injury. In group 2, the cautery was placed in the distal esophagus and a circumferential thermal burn injury was created. In group 3, an identical burn injury was created and a DEDE stent was placed at the site of injury and secured. On postoperative day 28, animals were sacrificed, and the distal esophagi were harvested and processed for histology. Submucosal collagen area was quantified histologically and compared across the 3 experimental groups. RESULTS: After the investigators controlled for luminal circumference and multiple measurements, submucosal collagen area was increased in group 2 (burn) compared with group 1 (sham) (P = .012). Submucosal collagen area was decreased in group 3 (DEDE stent) compared with group 2 (P = .042). No statistically significant difference in submucosal collagen area was observed between animals in group 1 and group 3 (P = .800). CONCLUSIONS;Topical application of mithramycin-A via a DEDE stent modulates collagen deposition after acute thermal injury in the rat esophagus.

Combined antegrade and retrograde esophageal dilation for head and neck cancer-related complete esophageal stenosis.

OBJECTIVES/HYPOTHESIS: Assess the safety and efficacy of combined antegrade and retrograde esophageal dilation (CARD) for complete esophageal stenosis following head and neck cancer (HNC) treatment. Review HNC dysphagia management. STUDY DESIGN: Retrospective review of all patients undergoing CARD following HNC treatment between May 2001 and September 2008. METHODS: Forty-five patients were identified for review. Parameters assessed included: ability to obtain intraoperative esophageal patency, complications, number of dilations required, diet, and gastric tube (GT) status. Factors associated with dilation failure were analyzed. RESULTS: Intraoperative esophageal patency was obtained in 91% of patients. Median number of all dilations per patient was three. Median number of CARDs per patient was one. Resumption of oral intake occurred in 36/45 (80%). Diet results included: regular or soft diet 32/45 (71%), GT removal 27/45 (60%), and GT dependence with nothing by mouth 9/45 (20%). Laryngeal and pharyngeal stenosis, radionecrosis, tracheotomy dependence, and elongated stenosis were associated with dilation failure. Complications occurred in 18/63 (29%) CARD procedures: eight pneumomediastinum, seven GT site problems, two esophageal perforations, and one pharyngeal infection. All complications resolved spontaneously or with minimal interventions. CONCLUSIONS: CARD was safe and effective. Intraoperative patency was achieved in 91% of patients. Eighty percent resumed oral intake. The majority of patients had their GTs removed and resumed a soft or regular diet. Dilation failure was associated with laryngeal, pharyngeal, and excessively long esophageal stenosis, often resulting from radionecrosis. Complications were minor. CARD should be considered before relegating patients with complete esophageal stenosis to chronic GT dependence or subjecting them to laryngopharyngo esophagectomy.

In-vitro reconstitution of three-dimensional human salivary gland tissue structures.

This study aimed to achieve functional reconstitution of salivary units from human salivary gland cells in an in vitro three-dimensional culture system. Human salivary cells were isolated from human salivary gland tissue, cultured, expanded, and placed into a three-dimensional culture system containing collagen and matrigel. Morphogenesis of reconstituted salivary structures was assessed by histomorphometry and transmission electron microscopy. Phenotypic and functional characteristics were assessed by immunohistochemistry and reverse transcription polymerase chain reaction (occludin, claudin 1, ZO-1, aquaporin 5, amylase) as well as spectrophotometric biochemical assay to measure amylase production. In a novel gel culture system, single human salivary cells divided and assembled into three-dimensional acinar and ductal structures in the presence of collagen and matrigel. All salivary gland units produced amylase and expressed aquaporin-5, a critical water channel protein. Tight junction proteins ZO-1, occludin, and claudin-1 were expressed under all culture conditions. Electron microscopy demonstrated desmosomes, microvilli, and secretory granules. This study showed that functional, differentiated salivary units containing acini and ducts formed from single salivary cells in a three-dimensional culture system. This in vitro culture system could be used to engineer functional salivary tissue in vivo.