Using the Ki-67 index is superior to using cytology and growth pattern as prognostic factors in MCL. The modified combination of the Ki-67 index and MIPI showed a refined risk stratification, reflecting their strong complementary prognostic effects while integrating the most relevant prognostic factors available in clinical routine.

No abstract

Mantle cell lymphoma (MCL) has a heterogeneous clinical course and is mainly an aggressive B cell non-Hodgkin lymphoma; however, there are some indolent cases The Ki-67 index, defined by the percentage of Ki-67-positive lymphoma cells on histopathological slides, has been shown to be a very powerful prognostic biomarker. The pathology panel of the European MCL Network evaluated methods to assess the Ki-67 index including stringent counting, digital image analysis, and estimation by eyeballing. Counting of 2×500 lymphoma cells is the gold standard to assess the Ki-67 index since this value has been shown to predict survival in prospective randomized trials of the European MCL Network. Estimation by eyeballing and digital image analysis showed a poor concordance with the gold standard (concordance correla-J Hematopathol (2009)

Thyroid transcription factor-1 (TTF-1) and surfactant apoprotein A (SP-A) belong to tissue-specific markers expressed in the normal respiratory epithelium. Both proteins are expressed in some lung carcinomas, and they have potential diagnostic use. We performed an immunohistochemical study on 109 tumors to determine the usefulness of monoclonal SP-A (PE-10) and TTF-1 (8G7G3/1) antibodies in distinguishing primary and metastatic lung carcinomas ( n=54) from a broad spectrum of nonpulmonary tumors ( n=55). An immunoperoxidase method using a streptavidin-biotin kit was applied on paraffin sections. We found positive results for TTF-1 and SP-A in 75% and 46% of pulmonary adenocarcinomas and in 50% and 25% of pulmonary non-neuroendocrine large cell carcinomas (LCCs), respectively. Small cell lung carcinomas were TTF-1 positive in 89% of cases and completely negative for SP-A. Squamous cell carcinomas and carcinoid tumors were negative for both proteins. In the group of nonpulmonary tumors, TTF-1 was detected in 8 of 11 thyroid carcinomas and SP-A in 1 of 6 colorectal carcinomas. Other tumors, including seven cases of pleural mesothelioma, were negative for both TTF-1 and SP-A. The expression of both antibodies was independent of primary and metastatic sites of the tumor. We observed a significant decrease of SP-A immunoreactivity in poorly differentiated lung adenocarcinomas. The combination of anti-TTF-1 with anti-SP-A does not increase the diagnostic usefulness of TTF-1 alone. Because of its diagnostic utility TTF-1 should be added to a panel of antibodies used for assessing tumors of unknown origin.