Fræðigrein

Background and aims: Bronchopulmonary carcinoids (BPC) are rare tumors of neuroendocrine origin. These tumors are histologically classified into two distinctive forms, typical and the more malignant atypical BPC. We evaluated the epidemiology and results of treatment for BPC in Iceland with special emphasis on how atypical vs. typical histology relates to clinical behavior.

Material & methods: This retrospective nation-wide study included all cases of BPC diagnosed in Iceland from 1955-2005. Histology of all the cases was reviewed and survival was based on data obtained from medical records and vital statistics.

Results: BPC was diagnosed in 64 patients (22 males, mean age 49 yrs.), accounting for 1.9% of all lung neoplasms in Iceland. Average tumor-diameter was 2.5 cm (range 0.4-5.5), with typical histology in 54 (84%) and atypical in 10 patients (16%). Altogether 56 patients (87.5%) were operated on, most with lobectomy (82.1%). Forty eight patients were diagnosed in TNM stage I, two patients in stage II, four patients had mediastinal lymph node metastases (stage III) and distant metastases were diagnosed in 6 patients (stage IV), 2 of whom had typical histology. At follow-up, 5 out of 64 patients had died of the disease (7.8%), two of them with typical histology. Five-year disease specific survival was 96% for patients with typical and 70% with atypical histology (p<0.05).

Conclusion: BPCs usually behave as benign neoplasms, with excellent long-term survival after surgical removal. Metastases are more common in patients with atypical histology (40%), and their survival is worse. However patients with typical histology can metastasize (14.8%) and die from the disease. Therefore, histology (typical vs. atypical) can not be used with certainty to predict the clinical behaviour of these tumors.

Correspondence:

tomasgudbjartsson@hotmail.com

 

Table 1. Comparison of patient demographics and pathology for patients with BPC in Iceland 1955-2005, according to histology (typical vs. atypical). (Number of patients and percentages in parenthesis).

 

	Histology
	Typical	Atypical	Total
Female (%)	32 (59.3)	10 (100)	42 (65.6)
Average age	47	59,7
Peripheral location (%)	13 (24.1)	2 (20)	15 (23.4)
Tumor size (cm)	2.4	3.1
Nodal involvement (%)	6 (11,1)	2 (20)	8 (12.5)
Distant metastases	2 (3.7)	4 (40)	6 (9.4)

 

Table 2.  Presenting symptoms for 45 patients diagnosed with BPC in Iceland 1955-2005. Patients can have more than one symptom. Nineteen patients that were diagnosed incidentally (had no symptoms) are not shown.

 

	n	% (n=45)
Chest pain	18	28.1
Cough	17	26.6
Pneumonia	17	26.6
Hemoptysis	8	12.5
Dyspnoea	3	4.7
Carcinoid syndrome	3	4.7
Vena cava syndrome	1	1.6

 

Table 3.  TNM staging of 60 patients diagnosed with BPC in Iceland 1955-2005. (Number of patients and percentages in parenthesis).

 

	Histology
	Typical	Aypical	Total
Stage I	45 (83.3)	3 (30)	48 (80)
Stage II	0	2 (20)	2 (3.3)
Stage III	4 (7.4)	0	4 (6.7)
Stage IV	2 (3.7)	4 (40)	6 (10)

 

Table 4.  Number of BPC patients with metastases at diagnosis in intrapulmonar lymph nodes, mediastinal lymph nodes or distant metastases in Iceland 1955-2005. (Number of patients and percentage in parenthesis).

 

	Histology
	Typical (n=54)	Atypical (n=10)	Total (n=64)
Intrapulm. lymph nodes (N1)	3  (5.6)	0  (0)	3  (4.7)
Mediastinal lymph nodes (N2)	4  (7.4)	1  (10)	5  (7.8)
Liver	3  (5.6	2  (20)	5  (7.8)
Brain	0  (0)	1  (10)	1  (1.6)

 

 

 

Figures

 

 

Fig. 1.     Estimated survival (disease specific) of 64 patients with BPC in Iceland 1955-2005, according to histology (atypical vs. typical).

 

 

Estimated survival

Atypical

Typical

Years

 

 

 

Atypical