Interobserver variation in classifying lymphomas among hematopathologists

Diagnostic Pathology

Table 4 Details of the difficult cases ^a

Case no.	Consensus diagnosis	Discordance of the original diagnosis^b	Frequency of each diagnostic category^c
Case no.	Consensus diagnosis	Discordance of the original diagnosis^b	Concordance	Minor discordance	Major discordance	Serious discordance
86	MALT lymphoma	Minor	0	2	3	0
101	Extranodal NK/T-cell lymphoma^d	Major	0	1	3	0
19	Diffuse large B-cell lymphoma^d	-	4	0	3	0
83	Lymphoplasmacytic lymphoma	Minor	0	2	2	0
32	Diffuse large B-cell lymphoma	-	3	0	2	0
82	Lymphoplasmacytic lymphoma	Minor	2	4	1	0
113	Peripheral T-cell lymphoma, NOS	Major	1	2	1	0
78	Follicular lymphoma	-	3	2	1	0
36	Diffuse large B-cell lymphoma	-	0	5	0	0
100	Extranodal NK/T-cell lymphoma^d	Minor	0	5	0	0
93	Mixed cellularity classical HL	Minor	1	5	0	0
76	Follicular lymphoma	-	3	4	0	0
109	Nodular sclerosis classical HL	Major	3	4	0	0
98	Nodal marginal zone lymphoma	-	3	3	0	0
84	Lymphocyte-rich classical HL	Minor	1	2	0	0
91	Mixed cellularity classical HL	Minor	3	2	0	0
62	Diffuse large B-cell lymphoma^d	-	3	2	0	0
116	T lymphoblastic lymphoma	-	3	2	0	0
23	Diffuse large B-cell lymphoma	-	1	1	0	0
Total			23	30	11	0

^aDifficult cases were cases that at least 40% of hematopathologists (participants) made discordant diagnoses.
^bOriginal diagnoses, initially made by attending pathologists in clinical services, were also categorized into 4 categories by comparing to the consensus diagnoses. Blanks represent "concordance".
^cPlease see the description of each diagnostic category in Table 1.
^dCases that consensus diagnoses could not be reached at the initial meeting and additional investigations were performed before reaching the consensus diagnoses.

ISSN: 1746-1596