CT findings of adrenal schwannoma.

AIM: To analyse the computed tomography (CT) imaging features of patients with adrenal schwannoma. MATERIALS AND METHODS: Eight cases of adrenal schwannoma confirmed by histopathology were included in this study. All eight patients had undergone multiphase CT examinations. The features of the adrenal schwannoma in the CT images were analysed retrospectively in detail, including size, shape, margin, radiodensity, calcification, and enhancement pattern. RESULTS: There were six male and two female patients, with a median age of 44.5 years (range, 25-52 years). Two patients complained of right flank pain, and two with left upper abdominal discomfort, while the remaining patients were diagnosed by routine ultrasound examinations. On unenhanced CT images, all cases of adrenal schwannoma were well circumscribed, rounded or oval, heterogeneous masses with cystic components, with two cases exhibiting calcification, and three cases with septa. On enhanced CT images, all cases displayed mild heterogeneous enhancement of the tumour during the arterial phase, and progressive enhancement during the portal venous phase and equilibrium phase. CONCLUSION: Adrenal schwannoma commonly presents as a well-defined unilateral mass with cystic degeneration, septa, and a characteristic progressive contrast-enhancement pattern on multiphase enhanced scans.

Loss of TAK1 increases cell traction force in a ROS-dependent manner to drive epithelial-mesenchymal transition of cancer cells.

Epithelial-mesenchymal transition (EMT) is a crucial step in tumor progression, and the TGFß-SMAD signaling pathway as an inductor of EMT in many tumor types is well recognized. However, the role of non-canonical TGFß-TAK1 signaling in EMT remains unclear. Herein, we show that TAK1 deficiency drives metastatic skin squamous cell carcinoma earlier into EMT that is conditional on the elevated cellular ROS level. The expression of TAK1 is consistently reduced in invasive squamous cell carcinoma biopsies. Tumors derived from TAK1-deficient cells also exhibited pronounced invasive morphology. TAK1-deficient cancer cells adopt a more mesenchymal morphology characterized by higher number of focal adhesions, increase surface expression of integrin α5ß1 and active Rac1. Notably, these mutant cells exert an increased cell traction force, an early cellular response during TGFß1-induced EMT. The mRNA level of ZEB1 and SNAIL, transcription factors associated with mesenchymal phenotype is also upregulated in TAK1-deficient cancer cells compared with control cancer cells. We further show that TAK1 modulates Rac1 and RhoA GTPases activities via a redox-dependent downregulation of RhoA by Rac1, which involves the oxidative modification of low-molecular weight protein tyrosine phosphatase. Importantly, the treatment of TAK1-deficient cancer cells with Y27632, a selective inhibitor of Rho-associated protein kinase and antioxidant N-acetylcysteine augment and hinders EMT, respectively. Our findings suggest that a dysregulated balance in the activation of TGFß-TAK1 and TGFß-SMAD pathways is pivotal for TGFß1-induced EMT. Thus, TAK1 deficiency in metastatic cancer cells increases integrin:Rac-induced ROS, which negatively regulated Rho by LMW-PTP to accelerate EMT.

Clinical application of ipsilateral C7 nerve root transfer for treatment of C5 and C6 avulsion of brachial plexus.

We applied a nerve transfer, using the ipsilateral C7 nerve root to treat the C5 and C6 root avulsion of the brachial plexus. Four patients with C5 and C6 preganglionic injury were operated on with this new technique from 1998-2000. Transfer of the spinal accessory nerve to the suprascapular nerve was simultaneously done in 2 these patients. After a follow-up of 1-2.5 years, the muscle strength of elbow flexors recovered to M4 (Lovett) in all cases, shoulder abduction of >90 degrees with external rotation of 30-40 degrees was gained in two cases, and that of 15-45 degrees with no external rotation in the other two cases. No remarkable impairment was found in all C7-innervated muscles except for decrease of muscle power of 1 grade (Lovett) in the short run. This new technique shows promise as an efficacious and safe treatment for C5 and C6 root avulsion of the brachial plexus. However, it should be applied prudently when incomplete injuries of the lower trunk are involved.

Femoral nerve transfer for treatment of brachial plexus root avulsion.

Femoral nerve transfer to the muscular branches of the thenar and hypothenar muscles was performed to determine its protective effect on the hand intrinsic muscles. Seven cases of brachial plexus root avulsion treated from May of 1989 to October of 1991 were involved. The femoral nerve transfer to the muscular branches of the thenar and hypothenar muscles was done at the same stage of multiple neurotization. The muscular branches derived from the femoral nerve were isolated and coapted with the thenar muscle branch of the median nerve and the deep branch of the ulnar nerve. A groin flap was harvested simultaneously to form a skin-tube pedicle that covered the nerve bridge. At the second stage, when regeneration of the median and ulnar nerves was found to reach as far as the level of the wrist, the femoral nerve was divided and the muscular branches of the thenar and hypothenar muscles were anastomosed with the regenerated median and ulnar nerves. All the cases were followed up for more than 6 years. Six months after femoral nerve transfer, muscle power of the interosseous muscles and adductor pollicis recovered to MRC3, whereas that of the abductor pollicis brevis recovered to MRC1 to 2. Five cases underwent second-stage transfer. Four to five years of follow-up revealed that the muscle power of the interosseous muscles and adductor pollicis was MRC2 in one case, MRC1 in three cases, and MRC0 in one case. As for the donor area, muscle power of the quadriceps femoris reduced to M3 to 4 within 1 month after femoral nerve transfer and recovered to normal at 3 months. In conclusion, femoral nerve transfer to the muscular branches of the thenar and hypothenar muscles has some protective effect on the hand intrinsic muscles. The outcome of the second stage, however, is not satisfactory.

Long-term functional results of contralateral C7 transfer.

From 1986 to 1994, 82 patients with brachial plexus root avulsion were operated on using a contralateral C7 nerve-root transfer. Forty-four patients underwent a one-stage procedure in which the distal end of the ulnar nerve was anastomosed to the contralateral C7 root, and the other 38 underwent a two-stage procedure (first phase: C7 root --> ulnar nerve; second phase: ulnar nerve --> recipient nerve). Twenty postoperative cases were followed-up for 2 years. Of them, the ulnar nerve was transferred to the musculocutaneous nerve in six cases, with recovery of the biceps up to M3 in four and S3 in five cases; the ulnar nerve was transferred to the median nerve in eight cases, with recovery of the wrist and finger flexors up to M3 in five and S3 in six cases; the ulnar nerve was transferred to the radial nerve in four cases, with recovery of the triceps up to M4 in two and S3 in three cases; and the ulnar nerve was transferred to the thoracodorsal nerve in two cases, with recovery of the latissimus dorsi to M4 in one case. The total muscle recovery rate (up to M3) of the series was 60 percent, and the sensory recovery rate (S3) was 78 percent. Outcomes were related to patient age, operative delay, and whether or not the ulnar nerve was used as a bridge for transfer.

Entrapment of posterior interosseous nerve of forearm. Report of 25 cases.

Of the 25 cases of entrapment, or compression syndrome of the posterior interosseous nerve of the forearm reported, 23 were treated surgically. The compressing or entrapping factors found during the operations consisted of 14 sites in tendinous tissues, 12 in vessels, 6 in scar adhesions, and 3 unclear. Of 11 cases each had 2 or more compression sites. 19 patients underwent local decompression. And 4 cases had membranous and degenerated nerves resection and end-to-end anastomoses. Hypertrophy and inflammation appeared to be the main pathological changes in 10 cases. The causes and pathology are discussed and the early diagnosis and treatment emphasized.

Cervical nerve root transfer from contralateral normal side for treatment of brachial plexus root avulsions.

The authors had designed cervical root nerve transfer from the contralateral normal side for the treatment of brachial plexus root avulsions in August 1986. Since then, the operation was performed in 50 cases. Follow-up studies showed that resection of C-7 root from the healthy side produced no long-term ill effect except numbness and pain of the fingers and weakness of gripping strength shortly after the procedure. In 10 recipient nerves of 9 cases with follow-ups of more than 2 years, satisfactory results were seen in 7. This is a new approach for the treatment of persistent cases of brachial plexus avulsion.