Dedifferentiated liposarcoma of the thyroid gland: A case report

Liposarcoma is one of the most common soft tissue tumors that affect adults. Liposarcoma is typically identified in the retroperitoneum, trunk and extremities as a slow-growing mass, yet is rare in the thyroid gland. Herein, we report a case of dedifferentiated liposarcoma that developed in the thyroid gland, and performed a literature review. A 66-year-old male with a history of well-differentiated liposarcoma in the thymus presented with a rapidly enlarging mass in the thyroid gland. Malignancy was suspected due to the local extension of the tumor, and complete resection of the tumor was achieved. Tissue diagnosis from the tumor following surgery revealed that dedifferentiated liposarcoma, and tumor progression was difficult to control with adjuvant radiation and chemotherapy. This is, to the best of our knowledge, the first case to report dedifferentiated liposarcoma in the thyroid gland, and the difficulty in initial diagnosis as well as the aggressive features of dedifferentiated liposarcoma are highlighted.

Long-term olfactory function outcomes after pituitary surgery by endoscopic endonasal transsphenoidal approach

OBJECTIVES

To evaluate long-term olfactory outcomes in patients who underwent pituitary surgery through the endoscopic endonasal transsphenoidal approach (EETSA) by T&T olfactometer.

METHODS

We retrospectively reviewed 26 patients who underwent pituitary surgery via EETSA. Olfactory function was assessed by T&T olfactometer before and 6 months after surgery. The mean of recognition thresholds for five different odorants was used. The change in the mean recognition threshold values was evaluated in the entire cohort and the subgroup analysis was performed according to the age, sex, past history of pituitary surgery (primary surgery or revision surgery), histopathology (non-functioning adenoma (NFA) or functioning adenoma (FA)), reconstruction procedure (rescue flap or nasoseptal flap), and superior turbinate management (preserved or resected).

RESULTS

Of the 26 patients (12 men and 14 women, median age 53 years), 21 patients were newly diagnosed with pituitary gland tumor (16 NFAs, 5 FAs) and the remaining 5 were diagnosed with recurrent pituitary gland tumor (4 NFAs and 1 FA). In the whole cohort, the mean recognition threshold values of T&T olfactometer significantly improved after surgery (P=0.01). Thirteen out of 26 patients (50%) showed olfactory improvement, whereas only 3 (12%) showed deterioration. In the subgroup analysis, olfactory function outcomes were not significantly different between the subgroups with respect to the age, sex, past history of pituitary surgery, histopathology, reconstruction procedure, or superior turbinate management. The olfactory function tended to worsen in the revision surgery group compared to that in the primary surgery group, but not significantly (P=0.06).

CONCLUSIONS

The olfactory function was improved or maintained after pituitary surgery via EETSA in 88% of patients, indicating the benefits of low invasiveness of our surgical treatment. On the other hand, three patients (12%) demonstrated deterioration of olfactory function, suggesting that the risk of postoperative olfactory dysfunction should be informed to patients.

Japanese civilian and US military interaction in the evacuation of casualties from Camp Fuji

Historically, if US soldiers at Camp Fuji become severely ill or suffer trauma, they are transported by the ground ambulance, as the doctor-led air ambulance in eastern Shizuoka has never been permitted to land at Camp Fuji. However, it is widely recognised that severely ill or traumatised patients require time-dependent medical management. It was therefore agreed to undertake a joint exercise between the US medical assets of Camp Fuji and the doctor helicopters in eastern Shizuoka prefecture in evacuating a simulated severely ill or traumatised US soldier. The aim of this article is to describe the background and rationale between this collaboration between the civilian Japanese air ambulance and the US medical assets in Camp Fuji.

TRIOBP-5 sculpts stereocilia rootlets and stiffens supporting cells enabling hearing

TRIOBP remodels the cytoskeleton by forming unusually dense F-actin bundles and is implicated in human cancer, schizophrenia, and deafness. Mutations ablating human and mouse TRIOBP-4 and TRIOBP-5 isoforms are associated with profound deafness, as inner ear mechanosensory hair cells degenerate after stereocilia rootlets fail to develop. However, the mechanisms regulating formation of stereocilia rootlets by each TRIOBP isoform remain unknown. Using 3 new Triobp mouse models, we report that TRIOBP-5 is essential for thickening bundles of F-actin in rootlets, establishing their mature dimensions and for stiffening supporting cells of the auditory sensory epithelium. The coiled-coil domains of this isoform are required for reinforcement and maintenance of stereocilia rootlets. A loss of TRIOBP-5 in mouse results in dysmorphic rootlets that are abnormally thin in the cuticular plate but have increased widths and lengths within stereocilia cores, and causes progressive deafness recapitulating the human phenotype. Our study extends the current understanding of TRIOBP isoform-specific functions necessary for life-long hearing, with implications for insight into other TRIOBPopathies.

A retrospective multicenter study of sublingual gland carcinoma in Japan

OBJECTIVE

Salivary gland carcinoma is rare among head and neck cancers. Sublingual gland carcinoma, a type of salivary gland carcinoma, is even rarer; therefore, the number of cases at a single institute is too small for sufficient evaluation of tumor characteristics. We conducted a multicenter, retrospective analysis of sublingual gland carcinomas in patients who visited 12 institutions associated with the Kyoto Hospital and Affiliated Facilities Head and Neck Clinical Oncology Group.

METHODS

Thirteen previously untreated patients who visited the institutions between 2006 and 2015 were enrolled. The overall survival (OS) and disease-free survival (DFS) rates for all patients and by disease stage were analyzed. Statistical analyses were performed for all patients with respect to disease stage.

RESULTS

Eight of thirteen patients were diagnosed with adenoid cystic carcinoma on pathological study. A significant difference in OS rate was observed between patients with Stage I-III and Stage IV disease; however, the difference in DFS rate by disease stage was not significant.

CONCLUSION

Stage IV disease was identified as a poor prognostic factor in patients with sublingual gland carcinoma. However, even patients with Stage I-III disease experienced relatively short DFS. Distant metastasis is a serious problem among patients with sublingual gland carcinoma.

Transplantation of multiciliated airway cells derived from human iPS cells using an artificial tracheal patch into rat trachea

Tracheal resection is often performed for malignant tumours, congenital anomalies, inflammatory lesions, and traumatic injuries. There is no consensus on the best approach for the restoration of tracheal functionality in patients with tracheal defects. Artificial grafts made of polypropylene and collagen sponge have been clinically used by our group. However, 2 months are required to achieve adequate epithelialization of the grafts in humans. This study aimed to investigate the feasibility of transplantation therapy using an artificial trachea with human-induced pluripotent stem cell (hiPSC)-derived multiciliated airway cells (hiPSC-MCACs). Collagen vitrigel membrane, a biocompatible and absorbable material, was used as a scaffold to cover the artificial trachea with hiPSC-MCACs. Analyses of hiPSC-MCACs on collagen vitrigel membrane were performed by immunocytochemistry and electron microscopy and by assessing ciliary beat frequency. Along with the artificial trachea, hiPSC-MCACs were transplanted into surgically created tracheal defects of immunodeficient rats. The survival of transplanted cells was histologically evaluated at 1 and 2 weeks after the transplantation. The hiPSC-MCACs exhibited motile cilia on collagen vitrigel membrane. The surviving hiPSC-MCACs were observed in the endotracheal epithelium of the tracheal defect at 1 and 2 weeks after transplantation. These results suggest that hiPSC-MCAC is a useful candidate for tracheal reconstruction.

Collagen sponge scaffolds containing growth factors for the functional regeneration of tracheal epithelium

Tracheal epithelia have barrier and mucociliary clearance functions that prevent invasion of extraneous particles and infectious materials. Hence, following tracheal reconstructions, functional and morphological regeneration of epithelia is required to prevent respiratory declines and infectious diseases. Although growth factors (GFs) promote the regeneration of tracheal epithelial morphologies, it remains unclear whether tracheal grafts containing GFs are beneficial for regeneration of tracheal epithelial functions. Thus, we fabricated collagen sponge scaffolds containing insulin-like GF-1 (IGF-1) and the basic fibroblast, hepatocyte, and epidermal GFs (bFGFs, HGFs, and EGFs, respectively), and we evaluated the effects of the grafts on the functional regeneration of tracheal epithelia. Partial tracheal defects were imposed surgically, and collagen sponges containing IGF-1, bFGF, HGF, or EGF were then transplanted to defect sites. Subsequent immunofluorescence studies suggested that EGF and bFGF contribute to regular distributions of tight junction molecules, and tracer permeability assays suggested that EGF and bFGF promote regeneration of barrier function. Increased ciliogenesis was also observed using scanning electron microscopy in reconstructed regions treated with EGF- and bFGF-supplemented collagen sponges. However, bFGF-supplemented collagen sponges led to greater microsphere transport than did EGF-supplemented sponges. The present data suggested that collagen sponge scaffold containing bFGF promotes functional regeneration of tracheal epithelial tissues.

Evaluation of Cilia Function in Rat Trachea Reconstructed Using Collagen Sponge Scaffold Seeded with Adipose Tissue-Derived Stem Cells

The tracheal lumen is essential for conducting air to the lung alveoli and for voice production. However, patients with severe tracheal stenosis and malignant tumors invading the trachea often require tracheal resection. Recently, various reported tissue engineering methods for tracheal reconstruction show that regeneration of ciliated epithelium in the reconstructed areas, as well as preservation of the luminal structure is possible. However, only few studies report on the mucociliary transport function in reconstructed tracheae. We investigated mucociliary transport function within rat tracheal epithelium, reorganized after autologous adipose tissue-derived stem cell (ASC) transplantation. Rat ASCs were expanded in culture, and then seeded in a collagen sponge, which was physically supported with a polypropylene framework. The ASC-seeded collagen sponge was transplanted into the rat tracheal defect. We then examined the motility and transport function of cilia generated in the transplanted area using ciliary beat frequency (CBF) and microsphere movement analyses. Our data suggested that autologous ASC transplantation promoted ciliogenesis, consistent with previous reports. The CBF analysis revealed that motility of the cilia generated in the ASC group was comparable to that observed in the normal rat tracheal epithelium. Transport function in the ASC group was higher than that in the control group. These data suggested that autologous ASC transplantation increased ciliated cells in the reconstructed area without significantly disrupting cilia motility, thereby promoting transport function regeneration. Autologous ASC transplantation is expected to be beneficial in morphological and functional regeneration of tracheal epithelium. Anat Rec, 303:471-477, 2020. © 2019 American Association for Anatomy.

Alterations in macrophage polarization in injured murine vocal folds

OBJECTIVES

Macrophages are prominent inflammatory cells in wounds, and their phenotypes are altered during wound healing. They are reported to contribute to not only inflammatory responses but also tissue remodeling. However, few studies in vocal fold biology have focused on the function of macrophages. The purpose of this study was to investigate macrophage polarization and distribution in injured murine vocal folds.

STUDY DESIGN

Animal experiments with controls.

METHOD

Unilateral vocal fold stripping was performed on C57BL/6 mice, and larynges were harvested 1, 3, 5, 7, and 14 days postinjury. Immunohistochemical analysis of the vocal fold lamina propria was performed to detect the expression of classically activated (M1) and alternatively activated (M2) macrophage markers (inducible nitric oxide synthase [iNOS] and CD206, respectively) in F4/80+ macrophages.

RESULTS

The proportion of F4/80+ iNOS+ cells out of all F4/80+ cells tended to increase from day 1. F4/80+ iNOS+ cell percentage tended to be high at days 1 through 7 and declined to close to a normal level by day 14. F4/80+ CD206+ cell percentage tended to decrease at day 1 and then to increase the rest of the time. In the normal vocal fold, the majority of F4/80+ macrophages were only positive for CD206. F4/80+ iNOS+ CD206+ cells were observed at days 1 through 7.

CONCLUSION

The main population of injured sites gradually shifted from M1 to M2 marker-positive macrophages in murine vocal folds. However, coexistence of M1 and M2 markers in the same macrophages was observed. Our results suggest that macrophage phenotypes are regulated by complex tissue-derived signals and exhibit dynamic changes during wound healing.

LEVEL OF EVIDENCE

NA Laryngoscope, 129:E135-E142, 2019.

Insulin-like growth factor 1 promotes cochlear synapse regeneration after excitotoxic trauma in vitro

In the context of acquired sensorineural hearing loss (SNHL), cochlear hair cells have long been thought to be among the most vulnerable elements in mammalian cochleae. However, recent studies have indicated that the synaptic connection between inner hair cells (IHC) and spiral ganglion neurons (SGN) can be an important target for the treatment of SNHL. Our previous studies in patients with sudden SNHL demonstrated delayed and gradual hearing recovery following topical application of insulin-like growth factor 1 (IGF-1), suggesting that not only protective but also regenerative mechanisms may account for hearing recovery after treatment with IGF-1. We then hypothesized that IGF-1 has the potential to drive the regeneration of IHC-SGN synapses. To test this hypothesis, we investigated the effects of IGF-1 on IHC-SGN synapses using cochlear explant cultures from postnatal day 2 mice that had been damaged by exposure to the excitatory amino acids N-methyl-d-aspartate and kainate. Cochlear explants that lost IHC-SGN synapses upon exposure to excitatory amino acids were cultured with exogenous IGF-1 for an additional 48 h. We observed increased numbers of IHC-SGN synapses after exogenous IGF-1 application. Pharmacological inhibition of the IGF-1 receptor attenuated the restoration of IHC-SGN synapses by exogenous IGF-1. These findings indicated that IGF-1 induces regeneration of IHC-SGN synapses in cochlear explant cultures from postnatal day 2 mice. Therefore, in a future study we will perform in vivo experiments using adult mice to ascertain the effects of IGF-1 on the regeneration of IHC-SGN synapses.

Characterization of aged rat vocal fold fibroblasts

OBJECTIVES/HYPOTHESIS

To elucidate the aging physiology of the vocal folds, we examined the characters of aged vocal fold fibroblasts (VFFs) in various conditions.

STUDY DESIGN

In vitro study.

METHODS

VFFs from young (12-week-old) and aged (19-month-old) Sprague-Dawley rats were compared. Proliferative capacity, ratio of myofibroblast to fibroblast, myofibroblast function, and extracellular matrix production were examined in the following conditions: naïve, basic fibroblast growth factor (bFGF) supplemented, and hepatocyte growth factor (HGF) supplemented.

RESULTS

Aged VFFs demonstrated reduced proliferation by cell counting, though the ratio of Ki-67-positive cells showed no difference. Aged VFFs exhibited an increased expression of α-smooth muscle actin (α-SMA); however, they demonstrated no enhanced contractile ability in a gel contraction assay. Type I collagen protein was increased age dependently, accompanied with decreased Mmp1 and unchanged Col1a1 transcription. Type I collagen protein and α-SMA represented quite similar reduction patterns to bFGF or HGF administration.

CONCLUSIONS

The following possible characteristics of aged VFFs were implied: long duration of mitosis, increased myofibroblast population size with certain dysfunctions, reduced type I collagen turnover, and correlation between α-SMA expression and type I collagen metabolism. Further investigations of these features will help to clarify presbyphonia's pathology and establish treatment strategies.

LEVEL OF EVIDENCE

NA Laryngoscope, 129:E94-E101, 2019.

An attempt to measure the diametric relationship between slow and quick phases of nystagmus

OBJECTIVE

To investigate whether our original method can precisely evaluate the angle between slow and quick phases of nystagmus (vector angle) and to determine whether vector angle analysis is helpful in differentiating between horizontal nystagmus and mixed nystagmus with horizontal and vertical components.

METHODS

We included 20 healthy volunteers, 17 patients with horizontal nystagmus, and 15 patients with mixed nystagmus. Caloric nystagmus was recorded in healthy volunteers; positional nystagmus was recorded in each patient. We extracted the velocity of nystagmus from eye movement of each subject and analysed the vector angle.

RESULTS

In caloric nystagmus, the vector angle approached 180 degrees as slow-phase velocity increased, suggesting that our vector angle measurement is more reliable with faster nystagmus. Importantly, in horizontal nystagmus from peripheral vestibular disease, the vector angle similarly approached 180 degrees as slow-phase velocity increased; in contrast, the vector angle in cases of mixed nystagmus from vertebrobasilar insufficiency or spinocerebellar degeneration significantly differed from the angle of caloric nystagmus.

CONCLUSIONS

Vector angle analysis using our original algorithm can precisely evaluate the diametric relationship in vestibular nystagmus; it may be helpful in diagnosis of non-peripheral vestibular disorders.

Unknown primary squamous cell carcinoma of the head and neck: retrospective analysis of 80 cases

OBJECTIVES

The management of patients with cervical metastasis in head and neck cancer of unknown primary (HNCUP) remains controversial. This current multicenter retrospective study investigated the treatment outcomes of patients with HNCUP.

METHODS

The study included patients who were treated curatively at 12 institutions in Japan from January 2006 to December 2015.

RESULTS

Eighty patients with HNCUP were included. The median follow-up period was 34 months. The three-year overall survival (OS), disease-specific survival (DSS), regional relapse-free survival (RRFS), local progression-free survival (LPFS), and distant metastasis-free survival (DMFS) rates were 72.5%, 80.3%, 74.0%, 89.7%, and 86.9%, respectively. Nodal status was a significant factor for OS, DSS, RRFS, and DMFS; and extracapsular extension (ECE) was significant for OS and DSS. There was a distinct difference between the survival rates of patients with N1-2a and N2b-3 disease. RT was a significant positive factor for LPFS (3-year LPFS, RT 93.0% vs. no RT 83.0%, p = .043).

CONCLUSIONS

For N2a as well as N1 disease without ECE, a single treatment modality, including ND or RT alone is acceptable. When ND alone is performed, thorough monitoring should be continued during follow-up to identify the emergence of the primary lesion.

Glucocorticoid receptor expression in resident and hematopoietic cells in IgG4-related disease

Immunoglobulin G4-related disease is a rare immune-mediated disease characterized by the infiltration of IgG4-positive plasma cells and unique storiform fibrosis of multiple organs. The majority of IgG4-related disease patients respond to glucocorticoids, yet the precise mechanism of their action remains unclear. Pathological sections of the submaxillary gland, kidney, and retroperitoneum from 20 patients in total diagnosed with IgG4-related disease were analyzed for glucocorticoid receptor expression and the cell types expressing glucocorticoid receptor. Strong and abundant expression of glucocorticoid receptor was observed in the submaxillary gland, kidney, and retroperitoneum of IgG4-related disease patients, while glucocorticoid receptor was rarely or only faintly observed in the submaxillary gland of patients with Sjögren's syndrome, radicular cysts and sialolithiasis or in the healthy kidney. Glucocorticoid receptor was mainly expressed in fibro/myofibroblasts, CD4-positive T cells and IgG4-positive plasma cells in the submandibular glands and kidneys of IgG4-related disease patients. The abundant expression of glucocorticoid receptor in various types of cells, including resident fibro/myofibroblasts in IgG4-related disease patients might provide clues to the mechanism of steroid responsiveness in IgG4-related disease patients.

Comparison of osseous healing after sagittal split ramus osteotomy and intraoral vertical ramus osteotomy

The sagittal split ramus osteotomy (SSRO) is generally associated with greater postoperative stability than the intraoral vertical ramus osteotomy (IVRO); however, it entails a risk of inferior alveolar nerve damage. In contrast, IVRO has the disadvantages of slow postoperative osseous healing and projection of the antegonial notch, but inferior alveolar nerve damage is believed to be less likely. The purposes of this study were to compare the osseous healing processes associated with SSRO and IVRO and to investigate changes in mandibular width after IVRO in 29 patients undergoing mandibular setback. On computed tomography images, osseous healing was similar in patients undergoing SSRO and IVRO at 1year after surgery. Projection of the antegonial notch occurred after IVRO, but returned to the preoperative state within 1year. The results of the study indicate that IVRO is equivalent to SSRO with regard to both bone healing and morphological recovery of the mandible.

Development of a novel tissue-engineered nitinol frame artificial trachea with native-like physical characteristics

BACKGROUND

Tracheal reconstruction is complicated by the short length to which a trachea can be resected. We previously developed a biocompatible polypropylene frame artificial trachea, but it lacked the strength and flexibility of the native trachea. In contrast, nitinol may provide these physical characteristics. We developed a novel nitinol frame artificial trachea and examined its biocompatibility and safety in canine models.

METHODS

We constructed several nitinol frame prototypes and selected the frame that most closely reproduced the strength of the native canine trachea. This frame was used to create a collagen-coated artificial trachea that was implanted into 5 adult beagle dogs. The artificial trachea was first implanted into the pedicled omentum and placed in the abdomen. Three weeks later, the omentum-wrapped artificial trachea was moved into the thoracic cavity. The thoracic trachea was then partially resected and reconstructed using the artificial trachea. Follow-up bronchoscopic evaluation was performed, and the artificial trachea was histologically examined after the dogs were sacrificed.

RESULTS

Stenosis at the anastomosis sites was not observed in any dog. Survival for 18 months or longer was confirmed in all dogs but 1, which died after 9 months due to reasons unrelated to the artificial trachea. Histological examination confirmed respiratory epithelial regeneration on the artificial trachea's luminal surface. Severe foreign body reaction was not detected around the nitinol frame.

CONCLUSIONS

The novel nitinol artificial trachea reproduced the physical characteristics of the native trachea. We have confirmed cell engraftment, good biocompatibility, and survival of 18 months or longer for this artificial trachea in canine models.