Head and neck cancer surgery presents a number of unique challenges, not only for the surgeon but for the radiation oncologist who will subsequently treat those patients. Great care with an emphasis on precision must be taken to ensure that critical structures and tissues avoid collateral damage when possible. However, given the surgical site often lies in soft tissue, exact identification of the native tumor bed can present some difficulty for radiation planning.
The surgical and radiation oncology team at Providence Mission Hospital (Mission Viejo, Ca) elected to use a novel tumor bed marker called VeraForm for a sarcomatoid carcinoma. Led by James Bredenkamp, M.D. and Quang Luu, M.D., this patient received a VeraForm marker when the lesion was surgically removed, representing a first of its kind for head and neck cancer treatment. While new, VeraForm has already been placed in thousands of breast cancer patients to mark the lumpectomy tumor bed cavity. William Chou, M.D., led the effort for radiation oncology, as this patient subsequently received image planning and radiation therapy. The following is a detailed description of the procedure from the team:
The 64-year old noted a mass at the top of his larynx while shaving 6 months ago. A biopsy of the tumor demonstrated a very rare cancerous tumor called a sarcomatoid carcinoma. Subsequent imaging and metastatic work up revealed that the tumor was located to the top of his larynx, and there was no evidence of spread beyond the primary site. Optimal treatment for this tumor is surgery followed by radiation therapy. On August 31 he had complete resection of the tumor, which included partial removal of his laryngeal cartilages with preservation of his speech and swallowing functions. After removal of the tumor, while still in the operating room we placed a novel marking filament called VeraForm to facilitate the anticipated post-operative radiation therapy. This radiopaque adaptable continuous marker allowed us the precisely deploy it intra-operatively in the tumor bed ensuring that the primary site of the tumor receives maximal radiation while sparing adjacent vital structures.
As seen in Fig.1, after tumor resection, VeraForm was deployed around the tumor bed area. Due to the minimum profile and adaptability, we were able to easily deploy the filament around the critical structures to depict the surgical tumor bed location. Surgical closure is shown in Fig 2 with excellent cosmetic results.
The patient was discharged from the hospital the following morning speaking and swallowing normally. Two weeks post-surgery, the patient was scheduled for CT simulation and radiation planning. Once the patient started radiation, daily CBCT was used identify VeraForm to help improve daily setup accuracy. As seen in Fig. 3, VeraForm clearly delineated the margins of the surgical bed and provided a 3-dimensional radiation target. The figures show the area of deep margin of VeraForm (Magenta). Examples of nearby critical structures are displayed; Right Parotid (Salivary Gland) is shown blue and left Parotid is shown Pink. The spinal cord is shown green.
The increased confidence in the location of the resected tumor allowed us to reduce the radiation volumes while improving the accuracy of the post-operative radiation treatments. This is especially important in the head and neck region where critical organs are in close proximity to each other. The use of VeraForm may translate into better sparing of the surrounding normal tissue and reduce radiation related toxicities such as dysphagia (difficulty swallowing) and xerostomia (dryness of mouth).
This unique application of a novel tumor bed marker is encouraging for future sarcomatoid carcinoma and other head and neck cancer cases. Further, it demonstrates the applicability of VeraForm beyond breast cancer treatment toward other soft tissue cancers where identifying and treating the tumor bed remains a significant challenge for physicians and ultimately their patients.