Neoadjuvant Chemotherapy in Temporal Bone Carcinoma- Our Experience

Background:- Squamous cell carcinoma (SSC) of the temporal bone is a rare malignancy. These generally present in the advanced stage. Surgery in advanced stage is contra indicated i/v/o involvement of petrous apex, carotid artery encasement and extension into the infratemporal fossa. We intend to explore the effectiveness of Neoadjuvant Chemotherapy in downstaging these locally advanced tumors.

Methodology:- A retrospective analysis of prospectively maintained data of all Temporal bone malignancy cases evaluated in the Skull Base Clinic, between 2014–2015. 49 cases of SCC were evaluated in the clinic with HRCT temporal bone and Contrast MRI Temporal bone, as part of protocol. 23 patients were Pittsburg Stage IV, 11 Stage III, 12 Stage II and 3 were Stage I.

Neoadjuvant chemotherapy was given in 7 patients, out of the 23 stage IV patients and 1 out of 11, stage III patients. In 3 patients the disease was inoperable as it wasextending into ITF or was involving petrous apex or encasing carotid artery. In 5 patients the disease was advanced but operable with a waiting period of 5–6 weeks for surgery. They received NACT to prevent progression of disease. 7 pts received platinum and taxane combination based chemotherapy and 1 received Oral Metronomic chemotherapy.

Results:- Amongst the 3 inoperable cases, one pt. progressed after receiving 1 cycle, while the other two had partial response. One patient became operable but defaulted and hence, all three were advised adjuvant CTRT.

All the 5 patients with advanced but operable disease showed partial response on imaging. They were operated by Modified Subtotal Temporal bone Resection. Two pts showed complete pathological response. All went to receive adjuvant Radiotherapy/ chemo radiotherapy.

All pts tolerated NACT without toxicity.Partial response to NACT on imaging was seen in ⅞ (87.5%). Of the 5 operated patients, complete pathological response was seen in ⅖ patients (40%).Facial Nerve was preserved in ⅗ patients (60%)

Conclusion: NACT is a feasible option for locally advanced temporal bone carcinoma. The toxicity profile is acceptable. As in other head neck SCC sites, NACT in temporal bone SSC may help in volume reduction and function preservation. Long term oncological outcomes are awaited and may make a difference in these locally advanced diseases which occurs in regions with complex anatomy.