Zygomatic bone metastasis from hepatocellular carcinoma and the therapeutic efficacy of apatinib: A case report and literature review

RATIONALE

Hepatocellular carcinoma (HCC) metastases to the zygomatic bone are extremely uncommon, and the treatment of target drugs against such case is unknown.

PATIENT CONCERNS

A 48-year-old male patient was admitted to our hospital under suspicion of an advanced liver tumor due to an increase in levels of alpha-fetoprotein (AFP) after radiofrequency ablation for independent nodule in his liver 1 month before. He had a hepatitis B virus (HBV) history for 20 years without treatment.

DIAGNOSIS AND INTERVENTIONS

A diagnosis of primary HCC was made based on pathological examination following right hepatectomy. Seven months after the surgery, a mass in S8 was identified and treated by ARF. Twenty days later, a right zygomatic mass was observed and the incisional biopsy revealed metastasis from HCC. Due to side effects of chemotherapy, the metastatic zygomatic mass was treated with radioactive seed implantation. Despite these interventions, there was steady increase in AFP values as well as increase in size of the zygomatic mass. Hence, the patient was started on apatinib with a dose of 500 mg/day from 1 to 28 days per cycle for a duration of 10 months.

OUTCOMES

The AFP values were significantly decreased but the size of the zygomatic mass continued to increase indicating progression of disease. But the progression-free survival was more than 10 months. The patient exhibited adverse reactions which were controllable by symptomatic treatments. As of last follow-up, the patient is unwell with pain in the face, blurred vision in the right eye, dyscrasia, and exhibited difficulty in opening his mouth.

LESSONS

HCC metastases to the zygomatic bone are very aggressive with a very low incidence and immunohistochemistry is useful diagnostic indicators. Still now, there is no optimal treatment strategy for these patients. Apatinib may be a promising drug in the treatment of HCC metastases to the zygomatic bone.

Biologic Behavior of Hydroxyapatite Used in Facial Augmentation

INTRODUCTION

The recent finding that shrinkage of key areas of the facial skeleton contributes to the aging appearance of the face has prompted a search for the most appropriate bone-like implant material. Evidence that hydroxyapatite, in granular form, maintains volume in the long term supports its use in the correction of aging, in addition to its use in the correction of inherently deficient areas of the facial skeleton. The biologic response of hydroxyapatite needs to be fully understood for its use to be confidently recommended.

MATERIALS AND METHODS

Samples of 'living' hydroxyapatite from the anterior maxilla, zygoma, and mandible of 17 patients were analyzed. These were obtained during revision procedures performed between 6 months and 15 years following original placement on the facial skeleton.

RESULTS

Histology showed that in every case, the individual granules were embedded within a mass of collagen that made up about half of the total implant volume. The collagen mass also contained fine elastin, fibroblasts, lymphocytes, occasional granulomas, and vessels. By 2 years, a new compact bone containing osteoblasts and osteocytes was present in all specimens in the deep (osseous) aspect. Bone progressively replaced the original collagen between the granules with a sharply defined transition at the interface.

CONCLUSIONS

This study confirmed a two-stage biologic change following onlay placement of hydroxyapatite granules on the facial skeleton, i.e., initial collagen formation with subsequent conversion to bone. This integrates the implant with the host bone which stabilizes the implant position and shape initially and in long term.

NO LEVEL ASSIGNED

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors. www.springer.com/00266 .

[Zygomatic localization of Langerhans cell histiocytosis - a case report]

Langerhans cell histocytosis is a rare disease. LCH is reported mainly in children aged less than 15 years, however it may appear at any age. In this work, the case of 17-month boy is reported. The boy was admitted to the pediatric ophthalmology department in order to diagnose the swelling and bruising in the lower part of left orbit, which had lasted for one month before. The clinical status, various imaging techniques' results (MRI, TK and PET) and immunohistochemistry led to the final diagnosis of multisystem LCH (spread to masticator muscle and zygomatic bone). After the pharmacological therapy the total remission was achieved. Since four years the child is regularly controlled by oncologists and hematologists with no relapse reported.

The effects of denervation and formoterol administration on facial growth

OBJECTIVE

To identify and demonstrate possible alterations of skeletal structures which might follow either unilateral surgical denervation of the masseter muscle, unilateral intramuscular injection of formoterol directly into the masseter muscle, or intramuscular formoterol injection after surgical denervation.

MATERIALS AND METHODS

Male Sprague Dawley rats (N = 16; four weeks of age) were prepared as four groups: 1. surgical sham + saline injection into the masseter muscle (sham); 2. surgical denervation of the masseter muscle only (den.); 3. surgical denervation of the masseter muscle plus intramuscular formoterol injection into the affected muscle (den.+form.); 4. intramuscular formoterol injection into the masseter muscle only (form.). The specimens were submitted for CT examination, the skulls and hemimandibles were photographed and measurements of craniofacial bones were made.

RESULTS

In this relatively small sample, comparisons between non-experimental and experimental sides revealed differences, both within the groups and for the same measurements between groups, with the den. and den.+form. groups showing the most change. Relative increases in the gonial angle shown in these groups occurred bilaterally, with the change on the experimental side always greater in magnitude than the change on the contralateral side.

CONCLUSIONS

Surgical denervation of the masseter muscle leads to an alteration in the size and shape of the skeletal structures close to the zygoma and the mandible. The intramuscular injection of formoterol into denervated masseter muscle seems to limit this skeletal alteration after surgical denervation.

Denervation and beta2-adrenoceptor-agonist administration on craniofacial bone density

OBJECTIVE

Beta2-agonist medications are thought to have adverse effects on bone density. Surgical denervation and intramuscular beta2-agonist injections appear to have opposing effects on skeletal muscles. The present study has been designed to assess the effects of denervation of the masseter, intramuscular injection of a beta2-agonist and the combination of both procedures, on bone density in the craniofacial skeleton in rats.

MATERIALS AND METHODS

Sprague-Dawley rats were prepared as four groups: 1. surgical sham + saline injection into the masseter (sham); 2. surgical denervation of the masseter (den.); 3. surgical denervation of the masseter + intramuscular formoterol injection into the affected muscle (den.+form.); 4. intramuscular formoterol injection into the masseter (form.). All specimens were submitted for CT examination and volumetric calculations of the mineralised bone tissue were performed.

RESULTS

The sham and form. groups had a greater volume of mineralised bone in the zygoma on the experimental side compared with the control side. The maxilla on the experimental side had a higher volume of mineralised bone in the den.+form. and form. groups compared with the sham and den. groups. The control side of the maxilla had a higher volume of mineralised bone in the den.+form. and form. groups compared with the den. group only.

CONCLUSION

Intramuscular administration of formoterol appears to induce a bilateral increase in bone mineral density in the maxilla and the zygoma, likely explained as a secondary effect of the well-described increase in muscle mass and strength associated with beta2-agonist administration.

Efficacy of radioprotection in the prevention of radiation-induced craniofacial bone growth inhibition

It has been reported that radiotherapy-induced craniofacial deformities can occur in 66 to 100 percent of survivors of childhood head and neck cancers. Recent interest in the effectiveness of radioprotectors in the protection of normal tissue against radiation injury led us to investigate a possible role of radioprotection in the prevention of radiation-induced craniofacial bone growth inhibition. Therefore, the objective of this study was to use the radioprotective agent amifostine (Ethyol, WR-2721) as a probe to determine the effectiveness of radioprotection in the prevention of radiation-induced craniofacial bone growth inhibition after single-dose orthovoltage radiation to the infant rabbit orbital-zygomatic complex. Seven-week-old male New Zealand white rabbits were randomized into three groups (n = 10 each): group 1, 0 Gy (sham radiation); group 2, 35-Gy single-dose orthovoltage radiation; and group 3, 35-Gy single-dose orthovoltage radiation and amifostine (300 mg/kg intravenously, given 20 minutes before radiation). Serial radiographs and computed tomographic scans were obtained for cephalometric analysis, bone volume, and bone density measurements until skeletal maturity at 21 weeks. Significant (p < 0.05) reductions in orbital-zygomatic complex linear bone growth, bone volume, and bone density were observed after 35-Gy radiation compared with nonirradiated controls. No significant differences were noted between groups in cephalometric analysis of the nontreated (nonirradiated) left orbital-zygomatic complex, indicating no crossover effect from the radiation beam. However, pretreatment with amifostine, 20 minutes before 35-Gy radiation, resulted in significant (p < 0.05) preservation of linear bone growth, bone volume, and bone mineral density in the rabbit orbital-zygomatic complex compared with controls. This study demonstrated for the first time the effectiveness of a radioprotector in the prevention of radiation-induced craniofacial bone growth inhibition, and it paves the way for investigation into the pathogenic mechanism and prevention of radiotherapy-induced craniofacial deformities.

Bone gap healing in the dog using recombinant human bone morphogenetic protein-2

PURPOSE

This study investigated bone gap healing in a zygomatic arch defect using recombinant human bone morphogenetic protein-2 (rhBMP-2; Genetics Institute, Andover, MA) in an absorbable collagen sponge (ACS) carrier.

METHODS

Zygomatic arch osteotomies were completed 15 mm apart and the arch was mobilized in 6 adult female mongrel dogs. The segment was then repositioned laterally 8 to 10 mm and secured with a titanium reconstruction plate. Bone gaps in either the right or left arches received rhBMP-2, with the contralateral side being left empty in 4 animals and the defects received buffer/ACS without rhBMP-2 in 2 animals as controls. Submentovertex radiographs were taken immediately postoperatively and every 4 weeks until killing at 12 weeks.

RESULTS

Clinical evaluation indicated no significant differences in the degree of inflammation between the groups. However, the rhBMP-2 sites were found to be firm on palpation, in contrast to a soft tissue defect palpated in the control sites. Radiographic examination showed significant bone formation in all rhBMP-2 grafted sites as early as 4 weeks. The radiopacity of the bone continued to increase over the time of this study. Five of six control sites did not show bone formation through the course of this study. In addition to lack of bone formation, 5 of 6 control sites showed collapse of the repositioned arch. All arches in the rhBMP-2 sites remained in their lateral position and formed bone in the gaps. In 2 animals, bone formation moderately exceeded the confines of the gap, and in 2 animals excessive bone formation occurred.

CONCLUSIONS

This study confirms that rhBMP-2 has the potential to be used to stimulate bone gap healing in the craniofacial complex.

Teratological studies on craniofacial malformations

Craniofacial malformations cause great human suffering. The purpose of the experimental studies was to investigate teratogenically induced craniofacial malformations in the rat, and to study if vitamin B6 could prevent the teratogenically induced malformations in the rat. The aim of the clinical investigation was to compare mandibulofacial dysostosis (MFD) with hemifacial microsomia (HFM) and thalidomide-induced malformations restricted to the first and second branchial arches. In the experimental studies we used two different teratogenic agents, etretinate and BAPN (beta-aminoproprionitrile). Vitamin B6 was administered one day prior to and simultaneously with the teratogenic agent. The induced malformations were observed by direct microscopy, histology, differential staining, microdissection and enzyme histochemistry. Knowledge of isoenzymic differentiation was obtained by isoelectric focusing and polyacrylamide gel electrophoresis. The clinical features of 29 patients with MFD, 26 with HFM and seven with thalidomide-induced malformations were investigated. The patients underwent clinical investigations, radiography, tomography, computed tomography, surgical exploration and audiograms. The etretinate-induced syndrome in the rat shows similarities to first and second branchial arch syndromes in man. Defective formation of Meckel's cartilage and the cartilaginous skull base, the zygoma and the middle ear ossicles were prominent features of the observed malformations. The induced malformations were accompanied by increased staining for alkaline phosphatase (APase) in the skull and skull base cartilages and Meckel's cartilage. BAPN induced cleft palate in 95% of the cases and the teratogenically induced cleft palate was accompanied by a pathological differentiation pattern that could be traced by determination of isoenzymes in the palatal shelves as well as in amniotic fluid. Vitamin B6 could prevent the teratogenic malformations induced by etretinate and BAPN in the rat. Comparing MFD, HFM and thalidomide-induced malformations, all syndromes included patients with external, middle and inner ear malformations. Cranial nerve palsy/paresis was only seen in HFM and thalidomide-induced malformations. A relationship between disturbed neural crest cell migration and defects of the first and second branchial arches seems possible.