a 34-year - old lady was referred to our clinic with a history of progressive , painless swelling over the right lateral upper eyelid , for the past 1 year . there were no systemic symptoms including loss of appetite , loss of weight , fever or a headache . no significant medical , surgical or family history could be elicited . on examination , her uncorrected vision in the right eye was 6/10 , while in the left eye was 6/6 . intraocular pressures in the right and left eyes were 12 mmhg and 14 mmhg , respectively . there was a prominent swelling over the superotemporal aspect of the right eyebrow measuring 3 cm  2 cm in size [ fig palpation of the mass indicated a smooth surface , firm in consistency , and nontender . it was not attached to the skin but was adherent to the underlying structures , rendering it relatively immobile . fullness of the right eye upper lid anterior and posterior segment examination was normal in both eyes . the provisional diagnosis was a benign lacrimal gland tumor due to the long history , absence of pain , or any systemic features . a computed tomography ( ct ) scan of the orbit and brain , with contrast , showed a well - defined regular homogenous enhancement of lacrimal gland mass measuring 2.8 cm  1.8 cm  2.0 cm within the superolateral part of the right orbit [ fig . 2 ] . there was no extraconal , intraconal , intracranial , intraocular , or paranasal sinus involvement . computed tomography - scan showing the lacrimal gland tumor a resection of the tumor and the lacrimal gland was performed on february 8 , 2013 , through a subbrow incision . subsequent histopathological examination ( hpe ) demonstrated nodules of tumor cells with large , vesicular nuclei , and prominent nucleoli with frequent mitoses within the central area of the collecting lacrimal ducts [ fig . the tumor cells were positive for epithelial membrane antigen ( ema ) , ckit ( cd117 ) , and periodic acid - schiff ( pas / d ) but negative for s100 protein , cytokeratin-20 and melan a. thus , a diagnosis of primary adenocarcinoma of the lacrimal gland was made . histopathological examination of the lacrimal gland tumor ( 10 ) postoperatively , the right upper eyelid swelling resolved uneventfully . two months postexcision , a repeat ct brain , and orbit were done and showed diffuse enhancing soft tissue around the right orbit , which suggested inflammatory activity [ fig . 4 ] . so far , the patient has been well , and there is no sign of recurrence or metastasis . lacrimal gland fossa lesions may be divided into three categories : inflammatory , lymphoproliferative , and epithelial lesions . among epithelial lesions , furthermore , among the malignancies , adenoid cystic carcinoma is the most frequently found ( 66% ) , followed by a carcinoma - ex - pleomorphic adenoma ( 18% ) , primary adenocarcinoma ( 9% ) , and mucoepidermoid carcinoma ( 3% ) , in that order . primary ductal adenocarcinoma in the lacrimal glands is extremely rare , very aggressive and carries a poor prognosis . this tumor arises in the upper eyelid and usually presents as a mass accompanied by symptoms such as rapid growth , pseudoptosis , exophthalmos , dystopia , pain , and reduced visual acuity . however , patients with this disease are usually symptomless initially , leading them to be diagnosed at an advanced stage . radiological features which suggest malignancy are bony erosion , the irregular margin of the mass and focal calcification within the lesion . however , primary adenocarcinomas frequently present as well demarcated cystic lesions misleading the examiner into diagnosing it as benign . in this case , the patient did not have typical clinical features of a lacrimal gland malignancy . usually , malignant lesions of the lacrimal gland are characterized by a rapid growth in < 6 months , ptosis , ocular motility disturbances , diplopia , and bone erosion on radiographs . her ct orbit had shown a well - defined regular homogenous enhancement of lacrimal gland mass but with no radiological features of malignancy . in this case immunohistochemistry has been successfully utilized in the diagnosis of many adnexal tumors . however , since , primary ductal adenocarcinoma of the lacrimal gland is very rare , only a few markers have been reported . these include ema , carcinoembryonic antigen , matrix metalloproteins-2 , 9 , and 13 , cytokeratin 7 and proto - oncogene human epidermal growth factor receptor-2/neu . currently , there is no clear protocol for treatment of primary ductal adenocarcinoma of the lacrimal gland due to the infrequent occurrence of this disease . however , in the majority of cases of lacrimal gland malignancies , the optimal treatment plan is complete removal of the tumor , orbital bone resection , and maintaining health and intact vision of the patient 's eye . in cases , where the tumor extends outside the orbit or is widely infiltrating the orbital structures , palliative treatment in the form of radiotherapy , or local resection can be done . if incompletely removed , the recurrence rate is high , and the disease can progress rapidly and may be fatal . thus , it has been recommended that radical excision of the lesion is essential to prevent such recurrence or progression . an en bloc resection of the orbital tumor and contents , together with orbitectomy , is considered to be the most logical and effective method of treatment . in our case , as the tumor was suspected to be benign we performed a local resection of the tumor along with the lacrimal gland . this case report seems to confirm the features of primary adenocarcinoma of the lacrimal gland , which is an extremely rare tumor . however , it also shows that this condition can have features mimicking a benign tumor . the authors certify that they have obtained all appropriate patient consent forms . in the form , the patient(s ) has / have given his / her / their consent for his / her / their images and other clinical information to be reported in the journal . the patients understand that their names and initials will not be published , and due efforts will be made to conceal their identity , but anonymity can not be guaranteed there are no conflicts of interest . the authors certify that they have obtained all appropriate patient consent forms . in the form , the patient(s ) has / have given his / her / their consent for his / her / their images and other clinical information to be reported in the journal . the patients understand that their names and initials will not be published , and due efforts will be made to conceal their identity , but anonymity can not be guaranteed