Review for 10.1186/1471-230X-9-93 (2009)

Reviewer's report
Title:A proposal for a new clinical classification of chronic pancreatitis
Version: 1Date:17 May 2009
Reviewer: Tobias Keck
Reviewer's report:
Büchler and coworkers describe in „A proposal for a new clinical classification of
chronic pancreatitis“ a clinically based classification system of chronic
pancreatitis. In their proposal they grade pancreatitis in levels A-C taking into
consideration pain, the development of complications and functional impairment
of the gland such as diabetes or exocrine insufficiency. The authors validate their
classification in 191 patients, who were operated for chronic pancreatitis in their
department over 3 years. Without doubt the current classification systems of
pancreatitis do not enough take into consideration morphological criteria that are
necessary for the development of guidelines for the treatment of various
alterations of chronic pancreatitis. Having this in mind for the focus of a new
classification system for chronic pancreatitis I have some comments concerning
the proposal suggested by Büchler and coauthors:
1. Already in 2002 Ramesh and coauthors (1) presented a similar A-C graded
classification system that the authors fail to cite. The classification system by
Ramesh and coworkers takes into consideration intermittent or unrelenting pain,
local complications and pancreatic insufficiency with diabetes mellitus and/or
steatorrhea. Even though their system leads to a different sub-grouping in A-C
and a somehow complicated abbreviated classification system, the underlying
criteria for the grouping of chronic pancreatitis remain the same. One of the
proposed advantages of the ABC system by Ramesh and couathors was, that it
eliminated problems caused by the disparity between the pathoanatomic stage of
the disease and the functional status. Many patients with severe morphologic
changes in their study were euglycemic and on the other hand some patients had
no pain were severely disabled by steatorrhea or severe insulin-dependent
diabetes mellitus. Given the fact that pathoanatomic changes play an important
role in the classification we suggest to include more objective parameters of the
morphometric differences such as the size of the pancreatic head in CT scan or
other imaging modalities.
a. How do the authors foresee to cope with the problems in severity classification
in their system?
b. The authors should include the Ramesh classification in their discussion and
introduction and work out the differences to their proposed classification.
c. The Ramesh classification never gained general acceptance or application,
even though taking into consideration similar parameters as the newly proposed
classification by Büchler et al. Why do the authors see that advancement or the
current classification will lead to a more widespread use?
2. In the present analysis by Büchler et al. only a small percentage of patients
were operated only due to pain the majority of patients were operated due to
additional complications. This distribution resembles the distribution from another
recently published series from a German center, which demonstrated a
comparable incidence of complications that lead to surgery in the German
collective rather than pain alone (2). In that publication the preoperative size of
the pancreatic head was compared to an US collective and significant differences
were found. Interestingly enough other groups from Germany presented as well
large pancreatic head tumors (3). Surgeons form the Netherlands with close
geographical neighborhood, however, did not find comparable pancreatic head
tumors in their series (4,5). This fact is relevant as this might be the reason for
the choice of varying technical surgical approaches to chronic pancreatitis. (e.g.
drainage procedures, Beger, Frey, Berne operation or classical Whipple or
pylorus preserving pancreatic head resection). In order to classify chronic
pancreatitis properly it seems therefore necessary to include objective
measurement of the pancreatic head. The authors should discuss this in their
manuscript.
3. In the classification system by proposed by Büchler et al Grade A is solely
based on the occurrence of pain. If this is the only criterion leading to the
diagnosis, there might be included a variety of diagnosis with abdominal pain that
do not necessarily comprise the patient with chronic pancreatitis. How do the
authors judge this problem?
4. There are several studies that propose a progression of the disease over time.
The concept by Ammann et al (6) that pain improves with the progression of
endocrine and especially exocrine insufficiency is mostly culled from patients'
retrospective historical data but has relatively little relevance in the management
of individual patients with severe or continuous pain. Do the authors think that a
time factor should be included in a classification system?
References
(1) Ramesh H. Proposal for a new grading system for chronic pancreatitis: the
ABC system J Clin Gastroenterol. 2002; 35(1):67-70.
(2) Keck T, Marjanovic G, Fernandez-del Castillo C, Makowiec F, Schäfer AO,
Rodriguez JR, Razo O, Hopt UT, Warshaw AL. The inflammatory pancreatic
head mass: significant differences in the anatomic pathology of German and
American patients with chronic pancreatitis determine very different surgical
strategies
Ann Surg. 2009; 249(1):105-10.
(3) Izbicki JR, Bloechle C, Broering DC, Knoefel WT, Kuechler T, Broelsch CE.
Extended drainage versus resection in surgery for chronic pancreatitis: a
prospective randomized trial comparing the longitudinal pancreaticojejunostomy
combined with local pancreatic head excision with the pylorus-preserving
pancreatoduodenectomy Ann Surg. 1998 Dec;228(6):771-9.
(4) van der Gaag NA, Boermeester MA, Gouma DJ. The inflammatory head
mass. Letter to the editor. Ann Surg 2009 (in press)
(5) Warshaw AL. The inflammatory head mass. Reply to letter to the editor. Ann
Surg 2009 (in press)
(6) Ammann RW. A clinically based classification system for alcoholic chronic
pancreatitis: summary of an international workshop on chronic pancreatitis.
Pancreas 1997; 14:215–21.
Level of interest: An article of importance in its field
Quality of written English: Acceptable
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I declare that I have no competing interests