General Information
About Small Cell Lung Cancer (SCLC)
·
Incidence and Mortality
·
Clinical Features
·
Diagnosis
·
Prognosis and Survival
SCLC accounts for approximately 15%
of bronchogenic carcinomas.
At the time of diagnosis,
approximately 30% of patients with SCLC will have tumors confined to the
hemithorax of origin, the mediastinum, or the supraclavicular lymph nodes.
These patients are designated as having limited-stage disease (LD).[1] Patients with tumors that have spread
beyond the supraclavicular areas are said to have extensive-stage disease (ED).
SCLC is more responsive to
chemotherapy and radiation therapy than other cell types of lung cancer;
however, a cure is difficult to achieve because SCLC has a greater tendency to
be widely disseminated by the time of diagnosis.
Incidence and Mortality
The overall incidence and mortality
rates of SCLC in the United States have decreased during the past few decades.[2]
Estimated new cases and deaths from
lung cancer (SCLC and non-small cell lung cancer [NSCLC] combined) in the United
States in 2015:[3]
·
New cases: 221,200.
·
Deaths: 158,040.
Clinical Features
Lung cancer may present with
symptoms or be found incidentally on chest imaging. Symptoms and signs may
result from the location of the primary local invasion or compression of
adjacent thoracic structures, distant metastases, or paraneoplastic phenomena.
The most common symptoms at presentation are worsening cough, shortness of
breath, and dyspnea. Other presenting symptoms include the following:
·
Chest pain.
·
Hoarseness.
·
Malaise.
·
Anorexia.
·
Weight loss.
·
Hemoptysis.
Symptoms may result from local
invasion or compression of adjacent thoracic structures, such as compression
involving the esophagus causing dysphagia, compression involving the laryngeal
nerves causing hoarseness, or compression involving the superior vena cava
causing facial edema and distension of the superficial veins of the head and
neck. Symptoms from distant metastases may also be present and include
neurological defect or personality change from brain metastases or pain from
bone metastases.
Infrequently, patients with SCLC may
present with symptoms and signs of one of the following paraneoplastic
syndromes:
·
Inappropriate antidiuretic hormone
secretion.
·
Cushing syndrome from secretion of
adrenocorticotropic hormone.
·
Paraneoplastic cerebellar degeneration.
·
Lambert-Eaton myasthenic syndrome.[2]
Physical examination may identify
enlarged supraclavicular lymphadenopathy, pleural effusion or lobar collapse,
unresolved pneumonia, or signs of associated disease such as chronic
obstructive pulmonary disease.
Diagnosis
Treatment options for patients are
determined by histology, stage, and general health and comorbidities of the
patient. Investigations of patients with suspected SCLC focus on confirming the
diagnosis and determining the extent of the disease.
The procedures used to determine the
presence of cancer include the following:
·
History.
·
Physical examination.
·
Routine laboratory evaluations.
·
Chest x-ray.
·
Chest computed tomography scan with
infusion of contrast material.
·
Biopsy.
Before a patient begins lung cancer
treatment, an experienced lung cancer pathologist must review the pathologic
material. This is critical because SCLC, which responds well to chemotherapy
and is generally not treated surgically, can be confused on microscopic
examination with NSCLC.[4] Immunohistochemistry and electron
microscopy are invaluable techniques for diagnosis and subclassification, but
most lung tumors can be classified by light microscopic criteria.
(Refer to the Staging Evaluation section in the Stage Information for SCLC section of
this summary for more information about tests and procedures used for staging.)
Prognosis and Survival
Regardless of stage, the current
prognosis for patients with SCLC is unsatisfactory despite improvements in
diagnosis and therapy made during the past 25 years. Without treatment, SCLC
has the most aggressive clinical course of any type of pulmonary tumor, with
median survival from diagnosis of only 2 to 4 months. About 10% of the total
population of SCLC patients remains free of disease during the 2 years from the
start of therapy, which is the time period during which most relapses occur.
Even these patients, however, are at risk of dying from lung cancer (both small
and non-small cell types).[5] The overall survival at 5 years is 5% to
10%.[1,5-7]
An important prognostic factor for
SCLC is the extent of disease. Patients with LD have a better prognosis than
patients with ED. For patients with LD, median survival of 16 to 24 months and
5-year survivals of 14% with current forms of treatment have been reported.[1,6,8,9] Patients diagnosed with LD who smoke should
be encouraged to stop smoking before undergoing combined-modality therapy
because continued smoking may compromise survival.[10]
Improved long-term survival in
patients with LD has been shown with combined-modality therapy.[9,11][Level of evidence: 1iiA] Although long-term
survivors have been reported among patients who received either surgery or
chemotherapy alone, chemotherapy combined with thoracic radiation therapy (TRT)
is considered the standard of care.[12] Adding TRT increases absolute survival by
approximately 5% over chemotherapy alone.[11,13] The optimal timing of TRT relative to
chemotherapy has been evaluated in multiple trials and meta-analyses with the
weight of evidence suggesting a small benefit to early TRT.[1,14,15][Level of evidence: 1iiA]
In patients with ED, median survival
of 6 to 12 months is reported with currently available therapy, but long-term
disease-free survival is rare.
Prophylactic cranial radiation
prevents central nervous system recurrence and can improve survival in patients
who have had a complete response to chemoradiation.[16,17][Level of evidence: 1iiA]
Thoracic radiation may also improve
long-term outcomes for these patients.[18]
All patients with this type of
cancer may appropriately be considered for inclusion in clinical trials at the
time of diagnosis. Information about ongoing clinical trials is available from
the NCI
Web site.
References
1.
Murray N, Coy P, Pater JL, et al.:
Importance of timing for thoracic irradiation in the combined modality treatment
of limited-stage small-cell lung cancer. The National Cancer Institute of
Canada Clinical Trials Group. J Clin Oncol 11 (2): 336-44, 1993. [PUBMED Abstract]
2.
Govindan R, Page N, Morgensztern D,
et al.: Changing epidemiology of small-cell lung cancer in the United States
over the last 30 years: analysis of the surveillance, epidemiologic, and end
results database. J Clin Oncol 24 (28): 4539-44, 2006. [PUBMED Abstract]
3.
American Cancer Society: Cancer
Facts and Figures 2015. Atlanta, Ga: American Cancer Society, 2015. Available online . Last accessed January 7, 2015.
4.
Travis WD, Colby TV, Corrin B, et
al.: Histological typing of lung and pleural tumours. 3rd ed. Berlin:
Springer-Verlag, 1999.
5.
Johnson BE, Grayson J, Makuch RW, et
al.: Ten-year survival of patients with small-cell lung cancer treated with
combination chemotherapy with or without irradiation. J Clin Oncol 8 (3):
396-401, 1990. [PUBMED Abstract]
6.
Fry WA, Menck HR, Winchester DP: The
National Cancer Data Base report on lung cancer. Cancer 77 (9): 1947-55,
1996. [PUBMED Abstract]
7.
Lassen U, Osterlind K, Hansen M, et
al.: Long-term survival in small-cell lung cancer: posttreatment
characteristics in patients surviving 5 to 18+ years--an analysis of 1,714
consecutive patients. J Clin Oncol 13 (5): 1215-20, 1995. [PUBMED Abstract]
8.
Turrisi AT 3rd, Kim K, Blum R, et
al.: Twice-daily compared with once-daily thoracic radiotherapy in limited
small-cell lung cancer treated concurrently with cisplatin and etoposide. N
Engl J Med 340 (4): 265-71, 1999. [PUBMED Abstract]
9.
Jänne PA, Freidlin B, Saxman S, et
al.: Twenty-five years of clinical research for patients with limited-stage
small cell lung carcinoma in North America. Cancer 95 (7): 1528-38, 2002. [PUBMED Abstract]
10.
Videtic GM, Stitt LW, Dar AR, et
al.: Continued cigarette smoking by patients receiving concurrent
chemoradiotherapy for limited-stage small-cell lung cancer is associated with
decreased survival. J Clin Oncol 21 (8): 1544-9, 2003. [PUBMED Abstract]
11.
Pignon JP, Arriagada R, Ihde DC, et
al.: A meta-analysis of thoracic radiotherapy for small-cell lung cancer. N
Engl J Med 327 (23): 1618-24, 1992. [PUBMED Abstract]
12.
Chandra V, Allen MS, Nichols FC 3rd,
et al.: The role of pulmonary resection in small cell lung cancer. Mayo Clin
Proc 81 (5): 619-24, 2006. [PUBMED Abstract]
13.
Warde P, Payne D: Does thoracic
irradiation improve survival and local control in limited-stage small-cell
carcinoma of the lung? A meta-analysis. J Clin Oncol 10 (6): 890-5, 1992. [PUBMED Abstract]
14.
Perry MC, Eaton WL, Propert KJ, et
al.: Chemotherapy with or without radiation therapy in limited small-cell
carcinoma of the lung. N Engl J Med 316 (15): 912-8, 1987. [PUBMED Abstract]
15.
Takada M, Fukuoka M, Kawahara M, et
al.: Phase III study of concurrent versus sequential thoracic radiotherapy in
combination with cisplatin and etoposide for limited-stage small-cell lung
cancer: results of the Japan Clinical Oncology Group Study 9104. J Clin Oncol
20 (14): 3054-60, 2002. [PUBMED Abstract]
16.
Aupérin A, Arriagada R, Pignon JP,
et al.: Prophylactic cranial irradiation for patients with small-cell lung cancer
in complete remission. Prophylactic Cranial Irradiation Overview Collaborative
Group. N Engl J Med 341 (7): 476-84, 1999. [PUBMED Abstract]
17.
Slotman B, Faivre-Finn C, Kramer G,
et al.: Prophylactic cranial irradiation in extensive small-cell lung cancer. N
Engl J Med 357 (7): 664-72, 2007. [PUBMED Abstract]
18.
Slotman BJ, van Tinteren H, Praag
JO, et al.: Use of thoracic radiotherapy for extensive stage small-cell lung
cancer: a phase 3 randomised controlled trial. Lancet 385 (9962): 36-42,
2015. [PUBMED Abstract]
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