Dr. Zaimal ShahanPGT

Capital Hospital,CDAIslamabad

Pleomorphic Adenoma of Minor Salivary Gland in

Parapharyngeal Space

Introduction Most common Parapharyngeal space tumors are PLEOMOROHIC ADENOMAS.Pleomorphic adenomas in the parapharyngeal space usually arise from deep lobe of the parotid, however they very rarely develop denovo from displaced or abberant salivary gland tissue within lymph node*.

We report a case of a large primary pleomorphic adenoma.It arised de novo from a minor salivary tissue in the right parapharyngeal space and presented with difficulty in breathing. Tumor was removed by transoral transpalatal approach. .

 

* H. Chijiwa, T. Mikhoki, B.Shir, et.al . Clinical Study of parapharyngeal space tumors. The journal of laryngology and otology. 2009; 123:100-103

  

EpidemiologyParapharyngeal space tumors account for some 0.5% of head and neck neoplasms . 82% being benign and 18% malignant.* Plemorphic adenomas being the most common benign parapharyngeal tumors (34%) *.On the other hand minor salivary gland neoplasms account for 22% of all salivary neoplasms **, majority being malignant.Pleomorphic adenoma is more common in females than in males (2:1 ratio). When it originates from the minor salivary glands, the tumor most commonly involves the palate followed by lip, buccal mucosa, floor of mouth, tongue, tonsil, pharynx, retromolar area and nasal cavity **.A comprehensive review of literature shows very few reports of peomorphic adenoma arising "de novo" in the parapharyngeal space **

* Riffat F, Dwivedi R.C, Palme C, Fish B, Jani P. A systematic review of 1143 parapharyngeal space tumors reported over 20 years. Oral Oncology. 2014;50(5):421-430** AH Hakeem, B Hazarika, SA Pradnan, R Knnan. Primary Pleomorphic adenoma of minor salivary gland in the parapharyngeal space. World Journal of Surgical Oncology. 2009:7:85*** Varghese BT, SebastianP, Abraham EK, Mathews A. A case report:"Pleomorphic adenoma of minor salivary gland in the parapharyngeal space".World Journal Surgical Oncol. 2003,1:2

DiagnosisThe cornerstone for diagnostic evaluation is appropriate radiologic investigation

1. Imaging studies• CT scan• MRI

2. Histopathology• FNAC

Treatment

Surgical excision is the treatment of choice:

Transcervical approach Transparotid approach Extended transmandibular approaches Transoral approach

CASE PRESENTATION

Patient Profile

• Age : 61 Years• Gender : Male• Residence : Islamabad• Admitted through OPD on 21st January 2013

Presenting Complaint

• Breathing difficulty since 2 years

History

• A 61 year old male presented in Otolaryngology outpatient department with history of difficulty in breathing for 2 years associated with Headache off and on, sore throat and difficulty in swallowing due to a mass in the pharynx.

• On inquiry he complained of a painless slowly progressing swelling in the nasopharynx on the right side for 7 years

• He was also advised surgery six months back but he left against medical advice.• There was no history of smoking or alcohol intake• There was history of DM for last 5 years and HTN for the last 8 years

Examination• Soft palatal and lateral

pharyngeal wall buldge on Rt. Side extending beyond midline and down up to the tonsil.

• No swelling in neck.• Normal nasal patency.• Tympanic Membrane and

hearing was normal

CT Scan

CT SCAN NECK WITH CONTRAST (11.O1.13)

•Revealed a well defined soft tissue density mass centered in Right Parapharyngeal space •37 mm transverse x 28 mm AP diameter with craniocaudal length of 43 mm.•Mass was oval in shape with surrounding smooth margins.•It compressed base of tongue.

MRI Scan

MRI SCAN NECK WITH CONTRAST (19th Feb,2013)

• Revealed a well defined soft tissue mass in parapharyngeal space on the right side.• 42 mm transverse and 39 mm AP diamension with 52 mmm craniocaudal extent.• It is causing midline shift and resultant narrowing of oropharynx and part of nasopharynx.• The mass is isointense on T1W1 while it is hypertintense on T2W1.• There are few foci inside the mass which are hyperintense on T1 and few brighter on T2• Mass is pushing carotid space laterally but fat plane between the mass and carotid space is intact.• No lymphadenopathy, bony involvement, intracranial extension noted• D/D 1. Salivary gland tumour2. Hemangioma 3. lymphoma

Incisional Biopsy• Incisional biopsy was

done on 5th January 2013 under G/A.

• Histopathology reports Chordoma

Provisional Diagnosis

He was diagnosed as a case of chordoma&

his excision was planned

Surgery• Mass was removed by

Transpalatal per-oral approach by splitting soft palate in Midline.

Per-op findings: Large mass in

nasopharynx, oropharynx and causing palatal buldge.

Well defined encapsulated mass was easily enucleated.

Post-op Care

Post Operative recovery was uneventful.

Injection Augmentin 1gm I/V BDInjection Diclofenic sodium 75 I/M SOSMouth wash gargles

Gross examination

Two off white well defined nodular pieces of tissue4 x 2 x 1.53 x 2.5 x 1.5

Cut Surface: Shiny, soft and homogenous.      

Histopathology

Pleomorphic Adenoma :

•Chondromyxoid background•Focally encapsulated•Nests and tubules of epithelial and myoepithelial cells.

FINAL DIAGNOSIS

Pleomorphic adenoma of Minor Salivary Glands in Parapharyngeal Space

Follow Up

Regular two monthly follow up was maintainedNo recurrence reported.