BRANCHIOGENIC CARCINOMA : A RARE MALIGNANT ENTITY INCIDENTALLY DETECTED IN A BRANCHIAL CLEFT CYST
Dr Rinku Susan Kurian1, Dr Sankar.S2
1Senior resident, Department of Pathology, Govt.Medical College,Kottayam, Kerala, India.
2Head and Professor, Department of Pathology, Govt.Medical College, Kottayam, Kerala, India
Received Date: 13/02/2022; Published Date: 04/04/2022.
*Corresponding author: Dr Rinku Susan Kurian1, Senior resident, Department of Pathology, Govt.Medical College,Kottayam, Kerala, India.
Branchiogenic carcinoma is a type of squamous cell carcinoma arising from the squamous lining of Branchial cleft cyst.We report a case of 59 year old lady who presented with a right sided neck swelling over 2 years which was situated in the classical location of branchial cleft cyst.MRI scan revealed a complex cystic lesion with internal septae and solid components with differential diagnosis as cystic schwannoma or infected branchial cleft cyst.We received excision specimen of the cystic mass,cut surface of which showed cystic and whitish solid areas.On microscopy,it was a cystic lesion lined by stratified squamous epithelium with subepithelial lymphoid aggregate.There were foci of full thickness dysplasia,carcinoma in situ and areas of invasive keratinising squamous cell carcinoma.Thus favouring a diagnosis of Branchiogenic carcinoma within a branchial cleft cyst. As branchiogenic carcinoma is a close mimicker of lymphnode metastasis from squamous cell carcinoma which show cystic degeneration. On follow up , pet scan showed increased uptake in tonsil area and bilateral tonsillectomy was done to exclude a primary carcinoma.Histopathological evaluation of bilateral tonsillectomy showed no dysplasia/ malignancy strengthening the diagnosis of Branchiogenic
Keywords:Branchiogeniccarcinoma,branchial cleft cyst
Branchiogenic carcinoma/ Branchial cleft cyst carcinoma is a squamous cell carcinoma arising from the squamous epithelium of a pre-existing branchial cleft cyst.It is a rare clinicopathological entity which mimics squamous cell carcinoma metastasis with cystic degeneration in lymphnode and thus it requires a strict follow up.The term was introduced byVolkmann in 1882,itwas described in a better manner by Martin et al in 1950 and further defined by Khaffif et al in 1989.(1)(2) Still there are controversies regarding the existence of this neoplasm.Here we are presenting a case of Branchiogenic carcinoma in a 56 year old lady who underwent excision of right sided neck swelling which was a Branchial cleft cyst clinically.
A 59 year old lady presented to an ENT specialist with a swelling on right side of neck persisting for 2 years.There was gradual increase in size.On examination of neck,a non tender,mobile ,soft and fluctuant swelling of size 6 x 4 cm was palpable involving the right level Ib,II and III cervical lymph node regions seen extending from anterior border of right sternocleidomastoid muscle to lateral border of thyroid cartilage.Clinical diagnosis was Branchial cleft cyst.Detailed examination of oral cavity ,throat and bilateral external auditory canalsrevealed no significant lesions.No lesions were identified on Indirect laryngoscopy.MRI scan of neck showed a complex cystic lesion with internal septae and solid component with heterogeneous post contrast enhancement in the right suprahyoid,parapharyngeal space measuring 4.8x3.6x6.3cm.The lesion is displacing right sternocleidomastoid muscle laterally and internal jugular vein- carotid artery medially.The differential diagnosis were Infected Branchial cleft cyst and Cystic Schwannoma.(Figure 1 & 2)
FNAC of the swelling yielded a clear fluid with sheets of macrophages ,scattered lymphocytes and neutrophils.There were no malignant cells.The patient underwent excision of the neck swelling. Grossly, it was a fat covered solitary,nodular and cystic soft tissue mass weighing 20 grams and measuring 7x5x4.5 cm.Dissection of mass extruded haemorrhagic thin fluid and cut surface showed multiloculatedcystic spaces separated by thin and thick septae with grey-white solid areas.Inner surface of large cystic spaces showed nodularity.(Figure 3 & 4)
Microscopic examination showed a cyst lined by stratified squamous epithelium with subepithelial lymphoid follicles with germinal centre.Cystic lumen was filled with eosinophilic material rich in cholesterol crystals.(Figure 5 & 6) Whitish solid areas were actually thickened septae with hyperplastic squamous epithelium which showed a transition from full thickness dysplasia, carcinoma in situ and invasive squamous cell carcinoma.(Figure 7) Invasive component showed frequent mitosis, nuclear pleomorphism and keratin pearl formation. (Figure 8 ) ) Thus it was reported as squamous cell carcinoma arising from a preexisting Branchial cleft cysts, that is Branchiogenic carcinoma. Squamous epithelium as well as the neoplastic foci of the cyst showed a strong and diffuse nuclear and cytoplasmic positivity for P16 on immunohistochemistry.(Figure 9)
Patient underwent whole body PET scan to rule out the possibility of Cystic lymphnode metastasis from Squamous cell carcinoma. PET scan revealed an increased uptake in bilateral tonsils.Thus a bilateral tonsillectomy was done , histopathological evaluation revealed only reactive hyperplasia only( figures 10 & 11).No dysplasia or invasive carcinoma identified on extensive sampling of the tissue.Actinomycete colony seen.( figure 12)
Branchiogenic carcinoma is a primary squamous cell carcinoma arising from the squamous lining of Branchial cleft cyst with evidence of transition from squamous dysplasia, carcinoma in situ and invasive carcinoma.Branchial cleft cyst carcinoma was first reported by Mr.Volkmann in 1882.(1) It created a confusion among the clinicians and pathologistsas most of the squamous cell carcinomas presenting as neck swelling are metastatic in origin with probable primary in oral cavity,throat,thyroid,salivary gland, sinonasal tract and upper aero digestive tract.
After studying several cases of Branchial cleft cystwhich turned out to be malignant masses,Martin and team proposed a diagnostic criteria for Primary carcinoma arising in a Branchial cleft cyst in 1950.(1) There were four criteria as follows;
1)Cervical tumor must have occurred somewhere along the line extending from a point just anterior to the tragus of ear, downward along the anterior border of sternocleidomastoid to clavicle.
2)Histological appearance of growth must be consistent with an origin from tissue known to be present in Branchial vestigia.
3)Patient must have survived and have been followed by periodic examination for at least 5 years without development of any other lesions which could possibly have been the primary tumor.
4)The best criterion of all would be histological demonstration of cancer develops in the wall of an epithelium lined cyst situated in lateral aspect of neck.
The fourth criterion by Martin et al is accepted as the only absolute proof for the existence of the malignant entity within a Branchial cleft cyst, the Branchiogenic carcinoma.(2) Our case satisfied 3 out of 4 of the above criteria and on follow up , we excluded the primary in bilateral tonsils.
In 1989,Khafif et al reported 67 cases of Branchiogenic carcinoma which was a retrospective analysis.He redefined the diagnostic criteria of the same by adding a fifth criterion,absence of any identifiable primary malignant tumor after exhaustive evaluation of the patient.(3) It is because of the fact that anatomical location of Branchiogenic carcinoma is same as that of metastatic cervical node,which makes it a controversial entity.In such situations, a diagnostic work up using PET-CT scan along with panendoscopydirect biopsies have to be done to identify any occult primaries and it is ideal to follow up the patient for at least 5 years as per Martin et al.(4) Wolff et al also emphasised the criterion that lining epithelium of Branchial cyst should demonstrate a stepwise escalation from normal,atypical,intraepithelial carcinoma to frankly invasive carcinoma.(5)
In a few case studies of Branchiogenic carcinoma, a strong p16 expression was observed in squamous epithelium,dysplastic epithelium as well as invasive squamous cell carcinoma within the Branchial cleft cyst.(6) But p16 staining was also observed in squamous cell carcinoma metastasis lymph node especially from oropharynx ,thus it became a non-specific marker.(7) All the cystic neck lesions in an adult patient is considered as malignant until otherwise proven. So excision of the mass or selective neck dissection for histopathological examination is the only way to establish a definite diagnosis.(8)
Branchiogenic carcinoma/Branchial cleft cyst carcinoma is still a controversial clinicopathological entity.A stepwise transition from normal squamous epithelium,dysplasia,carcinoma in situ and invasive squamous cell carcinomaobserved in a Branchial cleft cyst in classical anatomical location is the crucial histopathological feature of branchiogenic carcinoma on review of literature. Patient should undergo a thorough diagnostic work up and put on follow up for atleast 5 years to exclude the close differential diagnosis lymph node metastasis from squamous cell carcinoma which can be cystic in nature.
- Squamous cell carcinoma arising in Branchiogenic cyst Branchial cleft carcinoma: Victor R.Jablokow, Satinder Kathuria et al; Journal of Surgical Oncology1982;20:201-204
- Carcinoma arising in a Branchial cleft cyst:Allan Bernstein, Peter T Scardino et al; Cancer Journal 1976;37:2417-2422
- Squamous cell carcinoma arising in a second Branchial cleft cyst: Michael R. Girvigian, Aida K. Rechdouni et al; American journal of Clinical Oncology 2004;27:96-100
- 4.Primary Branchiogenic carcinoma: Report of a case and a review of the literature: Ashutosh Chauhan, Sangeeta Tiwari et al; Journal of Cancer research and therapeutics 2013; Vol 9: 135-137
- A case of Squamous cell carcinoma arising from Branchial cleft cyst: Takeshita Saito, TouruSato et al; Oral Science International 2008; Vol 5 :135-140
- Branchiogenic carcinoma with high risk type human papilloma virus infection: A case report: Hiroyuki Maeda, ZeyiDeng et al; Oncology letters 2016 ; 12: 2087-2091
- A case of P16 positive Branchiogenic carcinoma suspected as Lymphnode metastasis from an oropharyngeal carcinoma: RisaMasuda, TetsuroWakasugi et al; Practical otolaryngology Journal(Kyoto) supplement 2014; 138:110-111
- Branchial cleft cyst carcinoma: fact or fiction: Paula T.Bradley, Patrick J.Bradley; Current opinion Otolaryngology Head neck Surgery 2013; 21: 118-123