|LETTER TO EDITOR
|Year : 2022 | Volume
| Issue : 1 | Page : 181-182
Authors' reply to Sreeram and Subramaniam
Abhishek Mahajan1, Richa Vaish2, Shreya Shukla1, Ujjwa Agarwal1
1 Department of Radiodiagnosis, Tata Memorial Hospital, Tata Memorial Centre, HBNI, Dr. E Borges Road, Parel, Mumbai, Maharashtra, India
2 Department of Head and Neck Surgical Oncology, Tata Memorial Hospital, Tata Memorial Centre, HBNI, Dr. E Borges Road, Parel, Mumbai, Maharashtra, India
|Date of Submission||16-Feb-2022|
|Date of Decision||22-Feb-2022|
|Date of Acceptance||01-Mar-2022|
|Date of Web Publication||31-Mar-2022|
Fellowship in Cancer Imaging, MRes (KCL, London), FRCR (UK), Consultant Radiologist, The Clatterbridge Cancer Centre NHS, Foundation Trust, Pembroke Place, Liverpool, L7 8YA
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Mahajan A, Vaish R, Shukla S, Agarwal U. Authors' reply to Sreeram and Subramaniam. Cancer Res Stat Treat 2022;5:181-2
We were pleased to note the interest evinced by Sreeram and Subramanian in our article titled “Imaging-based T stage (iT) as a predictive and prognostic marker for outcome in T4 stage tongue carcinomas: A narrative review” and thank them for the comments. We agree that staging should be easy and comprehensive to apply. The staging system should be modified based on high level of evidence and expert and consensus opinion in the absence of high-level evidence.,, Tumor staging is predominantly, but not exclusively based on the anatomical extent of the disease. The staging systems are trying to incorporate non-anatomic factors like age in thyroid cancers, genomic profile for node-negative breast cancers, Gleason score for early prostate cancers, and so on. It is important to consider these non-anatomic prognostic factors in the era of personalized medicine, even though it may increase the complexity of staging. One of the important aims of the staging system is to accurately prognosticate the disease, and this gets compromised if factors that have an impact on prognosis are not incorporated in the staging system. T category was divided for advanced tumor into T4a, resectable and T4b, unresectable in the sixth edition American Joint Committee of Cancer (AJCC) staging system. These terms were replaced by moderately advanced and very advanced local disease, respectively, in the seventh edition of AJCC, as the concept of unresectability was subjective. This is rightly pointed out in the letter by the Sreeram et al based on the concept of masticator space involvement. Therefore, all T4b tumors may not always be unresectable.
We agree with the Sreeram et al that the proposed classification along with the existing T stage criteria need to be validated through a clinical trial and merit clinical applicability only if they have a significant impact on planning the type of therapy and clinical outcomes. However, the conceptualization of this proposal is in sync with the recent update on T4a oral cancer disease, which defines moderately advanced local disease as tumor >4 cm with depth of invasion (DOI) >10 mm. In a recently published study from our institution, we reported the results of 259 patients, which showed that unilateral and bilateral neurovascular bundle (NVB) involvement predicted poor prognosis and affected overall and disease-free survival on the univariate analysis. Type IV NVB involvement was found to be associated with T4a, presence of perineural invasion, and nodal metastasis. From here on, start a new paragraph categorizes masticator space, pterygoid plate, skull base, and encasement of internal carotid artery as T4b. This profile particularly describes sites like buccal mucosa, retromolar trigone, and alveolus and only the posterior extension in case of tongue cancer. There are other areas especially involved in tongue cancers that make the disease clearance difficult with adequate margins or result in extensive morbidity and dismal outcomes. One such area is involvement of the root of tongue with disease abutting the hyoid cartilage. The clearance in the third dimension in the proximity of the hyoid is difficult, and therefore, such tumors are often described as technically unresectable., Also, tumors more than 4 cm and DOI >1 cm are staged as T4 and such advanced tumors are seen to invade the deeper structures such as contralateral NVB if they grow medially, on the floor of mouth and hyoid inferiorly (along hyoglossus or direct extension), and parapharyngeal fat along the styloglossus muscle posteriorly.,,,, These factors usually have a direct or indirect impact on the selection of therapy (upfront surgery/neoadjuvant chemotherapy followed by surgery/extent of surgery/advanced palliative disease) and prognosis; however, this needs validation. We hope our article will lead to studies that validate or refute the hypothesis.
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Conflicts of interest
There are no conflicts of interest.
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