Detecting Tumour Cells

The introduction of methods more sensitive than histology for detecting tumour cells in surgical margins and lymph nodes could be helpful in obtaining better treatment results for patients with SCCs of the head and neck [53, 261, 361]. Their application, however, requires some critical remarks.

First, if histology is inadequate for reliable margin assessment, a lot of cases of SCC of the head and neck that have been classified as tumour-free after surgery by this method should nevertheless show recurrence at the site from which the tumour was removed.

Secondly, the usefulness of molecular detection of tumour cells in lymph nodes should be demonstrated by transferring patients from the histopathologically assessed N0 stage to the N+ stage. Merely detecting addi tional positive nodes in patients already classified as N+ is of debatable value.

In the third place, genetically altered cells are not always tumour cells. The whole epithelial lining of the upper aerodigestive tract bears the genetic burden of the carcinogenetic agents that cause SCCs and, therefore, these cells could have arisen independently from the invasive tumour [50, 268].

Also, there is no uniformity as to what constitutes a positive or negative surgical margin [26]. There is a broad spectrum of histological appearance between normal epithelium and fully developed SCC. If genetically altered cells are found in areas free of tumour but with atypical hyperplasia (severe dysplasia), molecular pathology does not provide any information compared with conventional microscopical examination.

In a recently published study, the value of molecular pathology was compared with traditional histology in the assessment of surgical margins and neck nodes in patients with SCCs of the head and neck [326]. It was found that from patients with microscopically positive margins, 22% had recurrence at the primary site. In contrast, of the cases with histologically tumour-free margins, only 4% showed recurrence of the tumour at the primary site. The authors concluded that conventional histology adequately identifies patients with SCCs of the head and neck at risk of local recurrence, leaving only very limited room for improvement using more sophisticated methods.

Regarding the neck, local recurrence was observed in 12 out of 107 cases in which a previous neck dissection was reported to be tumour-free. These neck recurrences could be due to the presence of micrometastases not detected by microscopy and improved methods for detecting them may reduce this number. However, it is still uncertain whether micrometastatic disease has the same clinical significance as metastatic disease detected by conventional methods [104].

The authors concluded that the added clinical value of molecular pathology over histology in detecting tumour cells in surgical margins in SCCs of the head and neck does not justify the effort. For lymph nodes, such an added value is still under discussion [326].

Mole Removal

Mole Removal

Moles, warts, and other unsightly irregularities of the skin can be bothersome and even embarrassing. They can be removed naturally... Removing Warts and Moles Naturally! If you have moles, warts, and other skin irregularities that you cannot cover up affecting the way you look, you can have them removed. Doctors can be extremely expensive. Learn the natural ways you can remove these irregularities in the comfort of your own home.

Get My Free Ebook


Post a comment