sympathetic innervation of the eye is a third - order neuron pathway which emerges from the hypothalamus and runs along a well - known route before reaching the eye [ 1 , 2 , 3 ] .
the third - order neuron is located in the superior cervical ganglion dividing itself into two branches which innervate the mller 's muscle of the eyelids , lacrimal gland , iris dilator muscle , facial sweat glands and the small skin vessels [ 1 , 2 , 3 ] .
horner 's syndrome , also called oculosympathetic paresis , results from any lesion that interrupts the sympathetic neuronal pathway from the hypothalamus to the eye .
it manifests ipsilaterally to the lesion , consisting mainly of miosis , slight ptosis and enophthalmos , but can present other findings [ 1 , 2 , 3 ] .
horner 's syndrome can be caused by many benign and malignant conditions [ 1 , 2 , 3 , 4 ] .
neoplasia is the most common cause and accounts for 3560% of all cases [ 2 , 3 , 4 ] .
the purpose of this paper is to present the case of a woman with a left cervical mass corresponding to a t - cell - rich b - cell non - hodgkin lymphoma that manifested horner 's syndrome due to a sympathetic third - order neuron lesion at diagnosis . to our knowledge
, this is the first case of horner 's syndrome secondary to a lesion in the post - ganglionic level of the sympathetic pathway in a non - hodgkin lymphoma .
a 35-year - old woman was admitted with a cervical lymphadenopathy which had progressively grown over the last 3 months .
it consisted of a coalescent group of hard lymph nodes that infiltrated adjacent tissues and skin , posteriorly located on the left side of the neck ( fig .
simultaneously she presented ipsilateral miosis , slight superior eyelid ptosis , and enophthalmos typical for horner 's syndrome ( fig .
the ocular phenylephrine 1%-test revealed minimal dilatation in the normal right pupil and pronounced dilatation in the left affected pupil ( fig .
ct scan of the neck confirmed a lymphadenopathy that occupied the carotid and paravertebral spaces .
thoracic ct scan did not show any tumor in the mediastine or left lung apex .
cervical tumor biopsy revealed a t - cell - rich b - cell non - hodgkin lymphoma [ immunohistochemistry : 100% large lymphocytes cd20(+ ) ; 40% large lymphocytes cd45(+ ) ; background lymphocytes cd3(+ ) ; cd15( ) ; cd30( ) ; alk-1( ) ] . as liver and bone marrow
were both compromised but without b symptoms , the tumor was classified as stage iva by the ann arbor staging system , and she was treated with 6 cycles of r - chop . until present , the patient has been receiving salvage chemotherapy with ifosfamide , carboplatin and etoposide due to a relapse affecting the lungs occurring after 2 years of complete clinical remission .
as soon as she reaches the second remission , she will undergo an autologous bone marrow transplant .
we found a small number of papers citing or describing horner 's syndrome related to non - hodgkin lymphomas [ 5 , 6 , 7 , 8 , 9 ] .
they were reported as tumors that primarily affected the intramedullary spinal cord ( c3-c6 ) , lung apex ( pancoast 's syndrome presentation ) [ 6 , 7 ] , the thyroid gland , or which were spread throughout the patient 's body including a supraclavicular lymphadenopathy .
these published cases , however , seem to be the result of sympathetic neuronal pathway interruption in the first-   or second - order neuron pathways [ 6 , 7 , 8 ] . in 1958 , giles and henderson   cited a case of malignant lymphoblastoma that caused horner 's syndrome in one of their study patients .
this tumor could correspond to a non - hodgkin lymphoma , but the sympathetic lesion level was not specified . according to danesh - meyer et al .
, the phenylephrine test finding observed in our patient locates the lesion in the third - order neuron level ( post - ganglionic ) .
this can be explained by the principle of denervation supersensitivity which occurs in the affected side . as the patient did not show hemifacial anhydrosis or flushing
, it seems that the lesion specifically affected the third - order neural branch along the internal carotid artery .
it is well - known that neck lymphadenopathy from any cause can result in horner 's syndrome .
nonetheless , our paper illustrates a rare presentation of non - hodgkin lymphoma , mainly because it seems to be the first well - documented case of a third - order sympathetic neuron lesion caused by this kind of malignancy .
 in this paper , we present the rare case of a patient with cervical lymphadenopathy diagnosed as a t - cell - rich b - cell non - hodgkin lymphoma that manifested horner 's syndrome due to a post - ganglionic sympathetic neuron lesion caused by the tumor . 
Introduction
Case Report
Discussion