Micrometastasis Detection using Special Stains in Nodal Tissues of Oral Squamous Cell Carcinoma - A Histochemical Study

Detection of micro-metastasis using cytokeratins (AE1/AE3) in haematoxylin & eosin-stained N0 lymph nodes of oral squamous cell carcinoma

Background & objectives

Oral squamous cell carcinoma (OSCC) is one of the most common malignancies affecting the head-and-neck region, regional lymph nodes being an important prognostication factor dictating the survival rate. Despite an array of modalities used, clinically, radiographically and routine histopathologically, the detection of micro-metastasis (2-3 mm tumour cell deposits) in the lymph nodes often escapes identification. The presence of few of these tumour epithelial cells in the lymph nodes drastically increases mortality and alters treatment plan. Hence, the identification of these cells is of major prognostic significance for a patient. Thus, the present study was aimed to evaluate and detect the efficacy of the immunohistochemical (IHC) marker [cytokeratin (CK) AE1/AE3] over routine Hematoxylin & eosin (H & E) staining in detecting micro-metastasis in the lymph nodes of OSCC cases.

Methods

Hundred H & E-stained N0 lymph nodes of OSCC cases treated with radical neck dissection were subjected to IHC with marker AE1/AE3 antibody cocktail for detecting micro-metastasis.

Results

The IHC marker CK cocktail (AE1/AE3) did not demonstrate any positive reactivity for the target antigen in all the 100 H & E stained lymph node sections evaluated in the present study.

Interpretation & conclusions

This study was undertaken to check the efficacy of IHC (CK cocktail AE1/AE3) in the detection of micro-metastasis in lymph nodes that are found to be negative in routine H&E stained sections. The findings of this study suggest that the IHC marker AE1/AE3 did not prove to be useful to detect micro-metastasis in this study population.

A retrospective study of pattern of recurrence after radical surgery for thoracic esophageal carcinoma with or without postoperative radiotherapy

The present study aimed to investigate the recurrence pattern of thoracic esophageal cancer (TEC) following radical surgery for guiding postoperative radiotherapy (PRT). Patterns of recurrence were analyzed in patients with recurrence for the first time after radical surgery at the First Affiliated Hospital of Anhui Medical University (Anhui, China) from January 2012 to December 2015. A total of 244 patients were reviewed in the study. The mean recurrence time for patients with PRT was >1 month longer than that for patients without PRT. The lymphatic, anastomotic and hematological recurrence ratios were 87.9 vs. 69.2%, 4.0 vs. 11.5% and 8.0 vs. 17.2%, respectively for patients without and with PRT. The most common recurrence regions were staion1 and station 2-4 (30.0 vs. 36.5% and 37.2% vs. 23.1%, respectively, for patients without and with PRT). The lymphatic recurrence of upper TEC was almost in station1 and station 2-4 (infield). The middle and lower TEC also had a high probability of lymphatic recurrence in station 1 and station 2-4 (totally 76.3 vs. 57.6% and 61.9 vs. 61.1%, respectively). The recurrence ratio significantly decreased in station 2-4 (infield) for middle TEC patients with PRT compared with patients without PRT (P=0.03), while no significant differences in the lymphatic recurrence ratios were observed in other regions (P>0.05). The differences of recurrence ratios in station 7, station 8 and celiac regions (infield) for lower TEC patients without and with PRT also demonstrated no statistical significance (P>0.05). The results of the present study indicated that the lower neck, supraclavicular regions and upper mediastinal regions (station 1, 2 and 4) should be included in the clinic target volume (CTV) for PRT, while lower mediastinal regions, celiac regions and anastomotic may not be included in CTV.