Nasopharyngeal carcinoma presenting as a sixth nerve palsy and Horner's syndrome

Etiology and Clinical Features of Diplopia in South China: Analysis of 303 Cases

Purpose

To provide a new classification system for diplopia and evaluate the etiology and clinical features of diplopia subtypes in south China.

Methods

In this retrospective study, all patients presenting with diplopia over the period from 2012 to 2014 in south China were reviewed. Patients were categorized into 3 groups according to their extraocular muscle (EOM) dysfunction: single EOM (sEOM), multiple EOMs (mEOMs), and a comitant strabismus group. Clinical data evaluated included age, sex, medical history, etiology and duration of diplopia, ocular alignment, and ocular motility.

Results

A total of 303 patients were enrolled. The most common type of EOM dysfunction was sEOM (158 cases, 52.1%), followed by mEOMs (n = 119, 39.3%), and finally the comitant strabismus group (n = 26, 8.6%). Overall, the most common cause of diplopia involved orbital diseases. Within the sEOM group, microangiopathy (n = 42, 26.6%) and trauma (n = 41, 25.9%) were the major etiologies, with the lateral rectus (LR) (n = 86, 54.4%) being the most frequently involved. There were 12 (4.0%) patients who were considered as nasopharyngeal carcinoma (NPC)-associated diplopia (10 caused by radiation neuropathy following radiation therapy). Thyroid associated ophthalmopathy (TAO, 56 cases, 47.1%) was the predominant etiology found in the mEOMs group. Acute acquired comitant esotropia (AACE, 14 cases, 53.9%) was the most common etiology in the comitant strabismus group.

Conclusions

This new classification system for assessing diplopia as based on EOM dysfunction represents an easy-to-follow approach that can be readily adapted for the clinical use. While microangiopathy and trauma represent common etiologies of diplopia, both orbital diseases and NPC-associated diplopia also warrant special attention when assessing diplopia within patients in south China.

Isolated Sixth Nerve Palsy as a First Presentation of Nasopharyngeal Carcinoma: A Case Series

Purpose

To describe isolated sixth nerve palsy as an uncommon presentation of nasopharyngeal carcinoma (NPC).

Patients and Methods

We analyzed the demographics, clinical presentation, neuroimaging findings, and pathological examination results of the nasopharyngeal masses of patients diagnosed with isolated sixth nerve palsy due to NPC.

Results

Isolated sixth nerve palsy as the first presenting sign of NPC was diagnosed in five patients. Two patients were aged <50 years and three were aged >50 years, and one of these three older patients had vascular risk factors. Most of the patients in our case study had an uncommon presentation of isolated sixth nerve palsy with diplopia, followed by typical NPC signs such as a neck lump (two patients), nasal obstruction (two patients), tinnitus (two patients), hearing loss (one patient), and epistaxis (one patient). Pathological examination revealed non-keratinizing NPC in all cases. Neuroimaging showed that the sites of tumor invasion were the clivus, Dorello's canal, and cavernous sinus, which explained the sixth nerve palsy. One patient whose NPC had progressed to the orbital apex later developed other cranial nerve palsies. Three patients underwent concurrent chemoradiotherapy (CCRT), and one patient underwent CCRT with adjuvant chemotherapy. The last patient was unfortunately lost to follow-up. The symptoms of four patients who underwent treatment improved.

Conclusion

Isolated sixth nerve palsy can be the first presentation of NPC, especially in patients aged <50 years old without microvascular risk factors or even in patients aged >50 years old with microvascular risk factors. This case study emphasizes that a thorough clinical history and careful physical and neuroimaging examinations might be necessary to rule out life-threatening conditions in patients with isolated sixth nerve palsy.

microRNA-18a from M2 Macrophages Inhibits TGFBR3 to Promote Nasopharyngeal Carcinoma Progression and Tumor Growth via TGF-β Signaling Pathway

OBJECTIVES

Nasopharyngeal carcinoma (NPC) is a type of nasopharyngeal disease with high metastasis and invasion properties. Tumor-associated alternative activated (M2) macrophages are evidenced to connect with NPC. Based on this, this study purposes to explore the mechanism and participation of microRNA-18a (miR-18a) from M2 macrophages in NPC.

METHODS

Peripheral blood mononuclear cells were differentiated to macrophages and macrophages were polarized to M2 type by interleukin-4. SUNE-1 and CNE2 cells were transfected with restored or depleted miR-18a or transforming growth factor-beta III receptor (TGFBR3) to explore their roles in NPC progression with the involvement of the TGF-β signaling pathway. Next, SUNE-1 and CNE2 cells were co-cultured with M2 macrophages that had been treated with restored or depleted miR-18a or TGFBR3 to comprehend their combined roles in NPC with the involvement of the TGF-β signaling pathway.

RESULTS

MiR-18a was highly expressed and TGFBR3 was lowly expressed in NPC cells. MiR-18a restoration, TGFBR3 knockdown or co-culture with miR-18a mimics, or si-TGFBR3-transfected M2 macrophages promoted SUNE-1 cell progression, tumor growth in mice, decreased p-Smad1/t-Smad1, and elevated p-Smad3/t-Smad3. miR-18a downregulation, TGFBR3 overexpression, or co-culture with miR-18a inhibitors or OE-TGFBR3-transfected M2 macrophages depressed CNE2 cell progression, tumor growth in mice, increased p-Smad1/t-Smad1, and decreased p-Smad3/t-Smad3.

CONCLUSION

Our study elucidates that miR-18a from M2 macrophages results in promoted NPC cell progression and tumor growth in nude mice via TGFBR3 repression, along with the Smad1 inactivation and Smad3 activation.