Complete pathological response is predictive for clinical outcome after tri-modality therapy for carcinomas of the superior pulmonary sulcus

Abstract

The objective was to define the relationship between histopathological changes after pre-operative chemo-radiotherapy (CRT) and clinical outcome following tri-modality therapy in patients with superior sulcus tumours. A retrospective analysis of tumour material was performed in a series of 46 patients who received tri-modality therapy between 1997 and 2007. Median follow-up was 34 months (5-154). Pathological complete response (pCR) was present in 20/46 tumours (43 %). The most common RECIST score after CRT in patients with pCR was a partial response (PR; 10/17, three unknown), whereas in patients without a pCR, stable disease was the most common (22/26) (p = 0.002). In 26 specimens with residual tumour, this was mainly located in the periphery of the lesion rather than the centre (Spearman's correlation = 0.67, p < 0.001). Prognosis was significantly better after a pCR compared to residual tumour (70 % 5-year overall survival vs. 20 %; p = 0.001) and in patients with fewer than 10 % vital tumour cells as compared to those with >10 % (65 % 5-year overall survival vs. 18 %; p < 0.001). A low mitotic count was associated with a longer disease-free survival (p = 0.02). Complete pathological response and the presence of fewer than 10 % vital tumour cells after pre-operative CRT are both associated with a more favourable prognosis. A modification of the pathological staging system after radiotherapy, incorporating the percentage of vital tumour cells, is proposed.

A prognostic score for non-small cell lung cancer resected after neoadjuvant therapy in comparison with the tumor-node-metastases classification and major pathological response

“…In the few cases of discordance, the agreement was reached by consensus after thorough discussion. Two previous studies have reported a high reproducibility in the assessment of MPR in NSCLC [30,31]. Specimen grossing as retrospectively evaluated for all tumors was for the majority of cases in line with the current IASLC guidelines advising complete inclusion of tumors <3 cm and sampling of at least 1 block per diameter of the tumor bed [ We assessed tumor regression as continuous variables using 1% increments till 10% and in 5% increments in cases showing >10% residual tumor in the primary tumor bed according to IASLC recommendations to calculate the adapted tumor size [16].…”

IASLC Multidisciplinary Recommendations for Pathologic Assessment of Lung Cancer Resection Specimens After Neoadjuvant Therapy

“…Depending on the size of the tumor, up to 58 paraffin blocks have been prepared in one study. 30 Blaauwgeers et al 51 evaluated on average seven blocks per case (range ¼ 3-15). 51 Other studies mostly focused on the histologic features, and little or no detail was provided on the methods of gross processing of tumors.…”

“…30 Blaauwgeers et al 51 evaluated on average seven blocks per case (range ¼ 3-15). 51 Other studies mostly focused on the histologic features, and little or no detail was provided on the methods of gross processing of tumors. [26][27][28]52 Pataer et al 26 identified histologic heterogeneity among submitted sections and suggested to submit at least one section per cm of resected tumor to adequately assess MPR.…”

“…The impact of evaluating lymph nodes, 54 diagnostic reproducibility of the response criteria among pathologists, 51,53 and the potential role of immunohistochemistry, 55 digital imaging, 55 and molecular studies after neoadjuvant treatment are largely unknown.…”

Gross handling of pulmonary resection specimen: maintaining the 3-dimensional orientation

“…These patients are commonly treated with induction chemoradiation therapy prior to resection in order to reduce the tumor size and increase the chance for surgical resection with free margins. Tumor should be sampled more extensively in order to evaluate the regression as tumors with complete or subtotal regression (<10% of tumor load) have favorable prognosis (13,14). If no microscopical tumor is found in the initially embedded tissue, more extensive sampling needs to be performed for possible detection of small clusters of vital tumor.…”