To the Editor:
We read with interest the paper by Miyoshi et al.1 We agree that T3 stage encompasses a large group of patients with depth of infiltration, ranging from just beyond the muscularis propria to mesorectal involvement without adjacent organ involvement and that this group needs to be divided further.
We feel that the paper is deficient in that it does not provide key information regarding the correlation between the presence and extent of mesorectal invasion and the lymph nodal status. This correlation could be established if the authors were to provide the frequency and survival figures for 4 distinct categories of patients: a) mesorectal invasion present, lymph nodes uninvolved; b) mesorectal invasion absent, lymph nodes uninvolved; c) mesorectal invasion absent, lymph nodes involved; and d) mesorectal invasion present, lymph nodes involved.
The findings of mesorectal invasion and its impact on survival would be further enhanced if results were to show a large number of mesorectum positive, lymph node-negative patients. On the other hand, the multivariate analysis in the paper simply establishes that both factors are independent prognostic factors.
What was the relationship between tumor differentiation and survival?
The basis and clinical significance of separation of tumors into type A and B are unclear. There appears to be no difference in the 2 groups. Further, the second data set does not show any such division.
We are concerned that noncontiguous involvement of the mesorectum2–4 would be overlooked by this technique of specimen assessment. What was the frequency of occurrence of noncontiguous involvement in the series?
Lastly, we are concerned that surgical techniques used during the period 1960 to 1969 and 1980 to 1997 are unlikely to be identical. The concept of mesorectal invasion and standard total mesorectal excision was standardized only in the late 1980s.4,5
H. Ramesh, MD
Manmohan Singh Bedi, MS
Sadiq S. Sikora, MS, FACS
Lakeshore Hospital & Research Center
Cochin, Kerala, India
hramesh@vsnl.com or
drhramesh@gmail.com
REFERENCES
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