Background
Development of tailored treatment based on immunohistochemical profiles (IPs) of tumors for cancers of unknown primary is needed.
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The primary tumor sites based on the immunohistochemical profiles (IPs)
for the 71 unknown primary patients were the lung for 17 patients,
digestive organs for 13, gynecological organs for 9, prostate for 7,
liver/kidney for 6, breast for 4, urothelial for 2, and were not
unclassified for 13 patients (
Table 2).
Figures 2 and
3 show typical IHC results for the breast and lung profiles.
~~~~~~~~~
Methodology/Principal Findings
"We developed an algorithm based on primary known adenocarcinoma for testing sensitivity and specificity. Formalin-fixed paraffin-embedded tissue samples from 71 patients of unfavorable subsets of unknown primary adenocarcinoma were obtained. We examined 15 molecular markers using the algorithm incorporating these IPs and classified the tumours into
9 subsets based on the primary tumour site. The sensitivity and specificity of this algorithm were 80.3% and 97.6%, respectively."
"Apparent primary sites were lung in 17 patients, digestive organs in 13,
gynecological organs in 9, prostate in 7, liver or kidney in 6, breast in 4, urothelial organ in 2, biliary tract and pancreatic profile in none, and unclassified in 13."
Response evaluation (treatment plan) and survival analysis:
"...... Response rates by profile are listed in
Table 2. A higher response rate was observed for the
gynecological profile (67%) than for the other profiles...."
Discussion:
"...Further, we consider gynecologic profile may not be necessary to be
classified into ovary, endometrial, and cervical adenocarcinoma in the
situation of adenocarcinoma of unknown primary because chemotherapies
for these cancer become similar in advanced disease
[32],
[33]..."
The algorithm we generated for orienting primary has value:
"Immunohistochemistory
is generally done in routine work for the diagnosis of adenocarcinoma
of unknown primary in many cancer centers. Therefore, there is no
additional skill or tool in the procedure of diagnosis
[10],
[25]."
"This study has some limitations. First, the prognostic value of each IP
was potentially underpowered, as the number of patients in each subgroup
was somewhat small, not allowing the response rate, PFS, and OS to be
compared to historical control data. Second, the results need to be
validated in a prospective manner by applying standard treatments for
identified primary profiles, to go beyond simply identifying prognostic
factors for unknown primary adenocarcinoma....
"In this study, we revealed the prognostic value of a panel composed of
immunohistochemistry profiles for patients with adenocarcinoma of
unknown primary who received
platinum doublet chemotherapy.
Orienting
primary sites either IHC or cDNA microarray in patients with CUPs is not
good enough, we need to examine survival benefit when applying
organ-oriented standard chemotherapies for patients with CUPs.
Our
results may encourage a prospective randomized trial to compare standard
platinum doublet chemotherapy with treatment determined by the IP. This
approach may assist in developing new treatment strategy compared to a
single arm platinum combination trial"
in the fall of 2004. The initiative's goal is to establish and evaluate a systematic, evidence-based process for assessing genetic tests and other applications of genomic technology in transition from research to clinical and public health practice. EGAPP also aims to integrate: 
