General Information
About Malignant Mesothelioma Treatment
·
Diagnosis and Prognostic Factors
o
Prognostic Scoring Systems
·
Follow-up and Survivorship
·
Carcinogenesis
Diagnosis and Prognostic Factors
Prognosis in malignant mesothelioma
is difficult to assess consistently because there is great variability in the
time before diagnosis and the rate of disease progression. In large
retrospective series of pleural mesothelioma patients, important prognostic
factors were found to be:[1,2][Level of evidence: 3iiiA]
·
Stage.
·
Age.
·
Performance status.
·
Histology.
Prognostic Scoring Systems
Two prognostic scoring systems have
been developed for advanced unresectable mesothelioma and are used to stratify
patients enrolling in clinical trials: the Cancer and Leukemia Group B (CALGB)
index and the European Organization for the Research and Treatment of Cancer
(EORTC) index.
CALGB index
The CALGB index was developed
retrospectively using the clinical characteristics of 337 patients treated on
clinical trials of chemotherapy for advanced mesothelioma during a 10-year
period.[3][Level of evidence: 3iiiA] These
characteristics were used collectively to define six prognostic groups with
median survivals ranging from 13.9 months (Eastern Cooperative Oncology Group
[ECOG] performance status [PS] = 0, age <49 years; or PS = 0, age ≥49
years and hemoglobin ≥14.6g/dL) to 1.4 months (PS = 1 or 2 and white blood cell
[WBC] count ≥15.6 × 109/L).
The prognostic value of the CALGB
index was evaluated retrospectively in a phase II clinical trial of 105
patients.[4][Level of evidence: 3iii] Median survival in
this study for patients in the best CALBG prognostic group was 29.9 months
compared with 1.8 months for patients in the worst prognostic group. However,
the intermediate groups 2 to 4 overlapped in their survival times.
EORTC index
The EORTC index was also developed
retrospectively using the characteristics of 181 patients from five phase II
clinical trials of chemotherapy during a 9-year period.[5][Level of evidence: 3iiiA] In a multivariate
analysis, the following characteristics were associated with poorer survival:
·
WBC count >8.3 × 109/L.
·
ECOG PS ≥1.
·
Unconfirmed histology on central
review.
·
Nonepithelioid histology.
·
Male gender.
Patients were allocated a numerical
prognostic score based on each of these variables (+0.55 if WBC >8.3 ×
109/L, +0.60 if ECOG PS ≥1, +0.52 if unconfirmed histology, and +0.60 if male
gender). Subsequently, patients were classified into two prognostic groups that
included low-risk patients with a prognostic score of ≤1.27
(0–2 risk factors) and high-risk patients with a prognostic score of >1.27
(3–5 risk factors). High-risk patients had a relative risk of death of 2.9
compared with low-risk patients, P < .001; the 1-year
survival rate was 40% for the low-risk group compared with 12% for the
high-risk group.
Follow-up and Survivorship
Multimodality therapy incorporating
radical surgery (extrapulmonary pneumonectomy or radical pleurectomy with
decortication) with or without chemotherapy, administered with or without
radiation, may be considered for patients with limited disease and has been
associated with a relatively long survival in observational series.[6][Level of evidence: 3iiiA] For patients treated
with aggressive surgical approaches, factors associated with improved long-term
survival include the following:[7,8][Level of evidence: 3iiiD]
·
Epithelioid histology.
·
Negative lymph nodes.
·
Negative surgical margins.
For those patients treated with
aggressive surgical approaches, nodal status is an important prognostic
factor.[7] Median survival has been reported as 16
months for patients with malignant pleural disease and 5 months for patients
with extensive disease. In some instances, the tumor grows through the
diaphragm making the site of origin difficult to assess. Cautious
interpretation of treatment results with this disease is imperative because of
the selection differences among series. Effusions, both pleural and peritoneal,
represent major symptomatic problems for at least 66% of the patients. (Refer
to the PDQ summary on Cardiopulmonary Syndromes for more
information.)
Carcinogenesis
A history of asbestos exposure is
reported in about 70% to 80% of all cases of mesothelioma.[1,9,10]
References
1.
Ruffie P, Feld R, Minkin S, et al.:
Diffuse malignant mesothelioma of the pleura in Ontario and Quebec: a
retrospective study of 332 patients. J Clin Oncol 7 (8): 1157-68, 1989. [PUBMED Abstract]
2.
Tammilehto L, Maasilta P, Kostiainen
S, et al.: Diagnosis and prognostic factors in malignant pleural mesothelioma:
a retrospective analysis of sixty-five patients. Respiration 59 (3): 129-35,
1992. [PUBMED Abstract]
3.
Herndon JE, Green MR, Chahinian AP,
et al.: Factors predictive of survival among 337 patients with mesothelioma
treated between 1984 and 1994 by the Cancer and Leukemia Group B. Chest 113
(3): 723-31, 1998. [PUBMED Abstract]
4.
Mikulski SM, Costanzi JJ, Vogelzang
NJ, et al.: Phase II trial of a single weekly intravenous dose of ranpirnase in
patients with unresectable malignant mesothelioma. J Clin Oncol 20 (1): 274-81,
2002. [PUBMED Abstract]
5.
Curran D, Sahmoud T, Therasse P, et
al.: Prognostic factors in patients with pleural mesothelioma: the European
Organization for Research and Treatment of Cancer experience. J Clin Oncol 16
(1): 145-52, 1998. [PUBMED Abstract]
6.
Flores RM, Pass HI, Seshan VE, et
al.: Extrapleural pneumonectomy versus pleurectomy/decortication in the
surgical management of malignant pleural mesothelioma: results in 663 patients.
J Thorac Cardiovasc Surg 135 (3): 620-6, 626.e1-3, 2008. [PUBMED Abstract]
7.
Sugarbaker DJ, Strauss GM, Lynch TJ,
et al.: Node status has prognostic significance in the multimodality therapy of
diffuse, malignant mesothelioma. J Clin Oncol 11 (6): 1172-8, 1993. [PUBMED Abstract]
8.
de Perrot M, Feld R, Cho BC, et al.:
Trimodality therapy with induction chemotherapy followed by extrapleural
pneumonectomy and adjuvant high-dose hemithoracic radiation for malignant
pleural mesothelioma. J Clin Oncol 27 (9): 1413-8, 2009. [PUBMED Abstract]
9.
Chailleux E, Dabouis G, Pioche D, et
al.: Prognostic factors in diffuse malignant pleural mesothelioma. A study of
167 patients. Chest 93 (1): 159-62, 1988. [PUBMED Abstract]
10.
Adams VI, Unni KK, Muhm JR, et al.:
Diffuse malignant mesothelioma of pleura. Diagnosis and survival in 92 cases.
Cancer 58 (7): 1540-51, 1986. [PUBMED Abstract]
