Although most colorectal malignancies are adenocarcinomas from mucosa, various types of malignant and benign tumors can develop. Due to extremely low incidence, little research has been conducted. The purpose was to assess incidence and compare it according to demographic factors.
Data from the Korea National Cancer Registry from 2007 to 2016 were used. The crude incidence, age-standard incidence rate (ASR) of colorectal nonadenocarcinomas were calculated.
Over 11 years, there were 267,142 patients with colorectal malignancies. The patients of 14,495 (5.43%) were diagnosed with nonadenocarcinoma. The ASR was 2.52 per 100,000 in men and 1.56 in women. Lesions were classified according to histologic categories; neuroendocrine tumor (NET) was the most common malignancy (10,919 [75.33%]). Nonadenocarcinoma was the most common in 40s and 50s (40 to 49 years, 3,530 [24.35%]; 50 to 59 years, 3,991 [27.53%]). Lymphoma was high (54.46%) in patients in teenagers. Proportion of NET decreased with age and that of carcinoma increased with age. Carcinoma, sarcoma, and lymphoma were more common among men and melanoma was more common among women. The most common site was the rectum (11,066 [76.34%]). Lymphoma occurred more frequently in proximal colon. Melanoma, gastrointestinal stromal tumor, and NET occurred mostly in rectum. A total of 10,155 patients (70.06%) were classified as having localized disease.
This study is meaningful as it is the first study to examine incidence of colorectal nonadenocarcinoma. Differences in incidence of different lesions based on demographic factors were identified. This study will play a role in cancer prevention and diagnosis projects.
Colorectal cancer has one of the highest incidences worldwide. It is the second most common malignancy in Europe and North America, following skin cancer [
In the United States, the incidence of NET is 0.3 per 100,000 in the colon and 1.1 per 100,000 in the rectum [
Some studies have examined colorectal nonadenocarcinoma, but studies about incidence are rare because of its low incidence. Therefore, the purpose of this study was to assess the incidence and identify the differences in the incidences of colorectal nonadenocarcinomas according to demographic factors using largescale data from the Korea National Cancer Registry.
We used data from the National Cancer Registry, which is managed by the Korea National Cancer Center. We included the data of patients from 2007 to 2016 with “Korean Standard Classification of Diseases Diagnostic Code” of C18, C19, or C20, which indicate malignancy of the colon and rectum. Patients were classified pathologically using the Korean morphologic code (M code) [
The purpose of this study was to investigate the incidence of colorectal nonadenocarcinoma. Therefore, most statistical analyses were performed to calculate the incidence and percentage. The variables used were sex, age, histological category, anatomical location, and SEER (Surveillance, Epidemiology and End Results) stage. To determine the incidence, the crude incidence and agestandard incidence were calculated. The population statistics in 2010 were used to calculate the age-standard incidence, and 95% confidence intervals were calculated. Cross-analysis was used to determine the characteristics of each histologic category according to age, sex, and anatomical location.
This study was approved by Institutional Review Board of National Health Insurance Service Ilsan Hospital (NHIMC 2018-07-007). The waiver of informed consent was granted for the collection of data from the existing medical records of patients.
We first identified the total number of patients with nonadenocarcinoma of the colon and rectum from 2007 to 2016 in the Korea National Cancer Registry data. Over 11 years, 267,142 patients were diagnosed with colorectal malignancy. Among these, there were 14,495 (5.43%) nonadenocarcinoma patients. We divided the patients into 6 categories based on histologic diagnosis of nonadenocarcinoma. Each category and histologic diagnosis with M code are described in
Demographic features of nonadenocarcinoma patients are described in
The number of patients and incidence of each nonadenocarcinoma were analyzed by sex (
We also analyzed incidence by age. The proportion of nonadenocarcinomas among total colorectal malignancies was higher in younger patients and decreased with increasing age (
We compared the incidence of nonadenocarcinomas according to the anatomical location of the colon (
The National Cancer Registry uses the SEER staging system. SEER stage is composed of localized disease, regional disease, distant disease, and unstaged disease. Among 14,495 patients, 10,155 patients (70.06%) were classified as having localized disease, 1,221 (8.42%) as having regional disease, and 1,138 (7.85%) as having distant disease. The SEER stage of each category of nonadenocarcinoma is shown in
In this study, we analyzed the incidence of colorectal nonadenocarcinoma in Korea. Compared to adenocarcinoma, nonadenocarcinoma in Korea showed some characteristic features. Colorectal nonadenocarcinoma accounted for 5.43% of all colorectal malignancies. The incidence of nonadenocarcinoma in Korea was much lower than that of adenocarcinoma. The age-standardized incidence rates of colon adenocarcinoma in 2014 were 64.8 per 100,000 in men and 44.0 in women [
There has been little examination of the incidence and characteristics of colorectal nonadenocarcinoma. DiSario et al. [
Neuroendocrine carcinoma of the colorectum accounts for 0.6% of all colorectal malignancies [
Squamous cell carcinoma accounted for 0.11% of the colorectal cancers in this study, which is similar to the results of a previous study that reported an incidence of 0.20% to 0.85% [
In previous studies, sarcoma accounted for 0.1% of all colorectal malignancies [
Colorectal GIST accounts for 5% to 6% of all gastrointestinal tract GIST [
In a previous study of 12 melanoma patients, there was a male predominance (1.4:1), and it was most common in the cecum and ascending colon [
Lymphoma occurred more frequently in the proximal colon, including the appendix, cecum, and ascending colon. Hangge et al. [
This is the first nationwide analysis of colorectal nonadenocarcinoma in Korea. We identified differences in nonadenocarcinoma incidence based on demographic factors. There was a limitation in that the data only contained information on stage using SEER and not the TNM staging system; therefore, it was impossible to analyze detailed stage-specific features of each tumor. Further, as the National Cancer Registry showed only the incidence result, statistical analysis of each category was impossible. However, we were able to identify incidence based on different characteristics in nonadenocarcinoma as compared to adenocarcinoma; for example, nonadenocarcinoma was relatively more prevalent in younger patients than adenocarcinoma.
In conclusion, this study was the first to examine the incidence of colorectal nonadenocarcinoma in Korea. The characteristics of each nonadenocarcinoma, including carcinoma-except adenocarcinoma, NET, sarcoma, GIST, melanoma, and lymphoma, were identified. Cancer prevention and future management projects should be based on the basic characteristics of colorectal nonadenocarcinoma identified in this study.
No potential conflict of interest relevant to this article was reported.
The composition of Korean M code.
The proportion of nonadenocarcinoma by location. NET, neuroendocrine tumors; GIST, gastrointestinal stromal tumor.
The SEER (Surveillance, Epidemiology and End Results) stage of nonadenocarcinoma. NET, neuroendocrine tumors; GIST, gastrointestinal stromal tumor.
Histologic diagnosis and categorization of nonadenocarcinoma of colon and rectum
Category | Histologic type | |
---|---|---|
1. Carcinoma | ||
1.1. Squamous cell carcinoma | Verrucous carcinoma (M80513), Papillary squamous cell carcinoma (M80523), Squamous cell carcinoma (M80703), Squamous cell carcinoma, keratinizing (M80713), Squamous cell carcinoma, large cell, nonkeratinizing (M80723), Squamous cell carcinoma, microinvasive (M80763), Basaloid cell carcinoma (M80833) | |
1.2. Other specified carcinoma | Carcinoma (M80103), Undifferentiated carcinoma (M80203), Anaplastic carcinoma (M80213), Pleomorphic carcinoma (M80223), Cloacogenic carcinoma (M81243), Transitional cell carcinoma (M81203), Adenosquamous carcinoma (M85603), Carcinosarcoma (M89803) | |
2. Neuroendocrine tumor (NET) | ||
2.1. NET | Neuroendocrine tumor (M82403) | |
2.2. Neuroendocrine carcinoma | Large cell neuroendocrine carcinoma (M80133), Small cell carcinoma (M80413), Mixed adenoneuroendocrine carcinoma (M82443), Neuroendocrine carcinoma (M82463) | |
3. Sarcoma | ||
3.1. Sarcoma, not otherwise specified | Sarcoma (M88003), Spindle cell sarcoma (M88013), Giant cell sarcoma (M88023), Epithelioid sarcoma (M88043), Undifferentiated sarcoma (M88053), Desmoplastic small round cell tumor (M88063), Fibrosarcoma (M88103), Infantile fibrosarcoma (M88143), Synovial sarcoma, spindle cell (M90413), Clear cell sarcoma (M90443) | |
3.2. Leiomyosarcoma | Leiomyosarcoma (M88903), Epithelioid leiomyosarcoma (M88913) | |
3.3. Other specified sarcoma | Hemangiosarcoma (M81203), Malignant fibrous histiocytoma (M88303), Well-differentiated liposarcoma (M88513), Myxoid liposarcoma (M88523), Pleomorphic liposarcoma (M88543), Mixed liposarcoma (M88553), Dedifferentiated liposarcoma (M88583), Rhabdomyosarcoma (M89003), Pleomorphic rhabdomyosarcoma (M89013), Embryonal rhabdomyosarcoma (M89103), Hemangiopericytoma (M91503), Peripheral neuroectodermal tumor (M93643), Malignant peripheral nerve sheath tumor (M95403), Malignant neurilemoma (M95603), Kaposi’s sarcoma (M91403) | |
4. Gastrointestinal stromal sarcoma (M89363) | ||
5. Melanoma | Malignant melanoma (M87203), Nodular melanoma (M87213), Amelanotic melanoma (M87303), Malignant melanoma in junctional nevus (M87403), Epitheloid cell melanoma (M87713), Spindle cell melanoma (M87723) | |
6. Lymphoma | Malignant lymphoma (M95903), Non-Hodgkin lymphoma (M95913), small B lymphocytic lymphoma (M96703), Large B-cell diffuse lymphoma (M96803), Large B-cell diffuse immunoblastic lymphoma (M96843), Mantle cell lymphoma (M96743), Burkitt lymphoma (M96873), Follicular lymphoma (M96903), Grade 1 follicular lymphoma (M96953), Grade 2 follicular lymphoma (M96913), Grade 3 follicular lymphoma (M96983), Marginal zone B-cell lymphoma (M96993), Mature T-cell lymphoma (M97023), Intestinal T-cell lymphoma (M97173), Anaplastic large cell lymphoma (M97143), NK/T-cell lymphoma (M97193), Plasmacytoma (M97313, M97343), Langerhans cell histiocytosis (M97513, 97543) |
Demographic features of nonadenocarcinoma patients (2007–2016)
Category | No. (%) |
---|---|
Total malignancy of colon and rectum | 267,142 (100) |
Nonadenocarcinoma patients | 14,495 (5.43) |
Adenocarinoma patients | 252,647 (94.57) |
Sex | |
Male | 8,760 (60.43) |
Female | 5,735 (39.57) |
Histologic category | |
1. Carcinoma | 1,454 (10.03) |
1.1. Squamous cell carcinoma | 288 (1.99) |
1.2. Other specified carcinoma | 1,166 (8.04) |
2. Neuroendocrine tumor (NET) | 10,919 (75.33) |
2.1. NET | 9,585 (66.13) |
2.2. Neuroendocrine carcinoma | 1,334 (9.20) |
3. Sarcoma | 156 (1.08) |
3.1. Sarcoma, not otherwise specified | 35 (0.24) |
3.2. Leiomyosarcoma | 56 (0.39) |
3.3. Other specified sarcoma | 65 (0.45) |
4. Gastrointestinal stromal sarcoma | 393 (2.71) |
5. Melanoma | 142 (0.98) |
6. Lymphoma | 1,431 (9.87) |
Age distribution (yr) | |
0–19 | 101 (0.70) |
20–29 | 424 (2.93) |
30–39 | 2,061 (14.22) |
40–49 | 3,530 (24.35) |
50–59 | 3,991 (27.53) |
60–69 | 2,531 (17.46) |
70–79 | 1,480 (10.21) |
≥ 80 | 377 (2.60) |
Anatomic distribution | |
Appendix | 241 (1.66) |
Cecum | 517 (3.57) |
Ascending colon | 523 (3.61) |
Hepatic flexure | 73 (0.50) |
Transverse colon | 171 (1.18) |
Splenic flexure | 16 (0.11) |
Descending colon | 110 (0.76) |
Sigmoid colon | 537 (3.70) |
Rectosigmoid colon | 265 (1.83) |
Rectum | 11,066 (76.34) |
Overlapping lesion | 67 (0.46) |
Not otherwise specified | 909 (6.27) |
SEER summary stage | |
Localized | 10,155 (70.06) |
Regional | 1,221 (8.42) |
Distant | 1,138 (7.85) |
Unstaged | 1,981 (13.67) |
SEER, Surveillance, Epidemiology, and End Results.
The number of patients and incidence of colorectal nonadenocarcinoma in male
Histologic category | No. (%) | Rate |
|
---|---|---|---|
CR | ASR (95% CI) | ||
Total malignancy of colon and rectum | 160,367 (100) | 63.85 | 46.66 (46.42–46.89) |
Nonadenocarcinoma patients | 8,760 (5.46) | 3.49 | 2.52 (2.47–2.58) |
1. Carcinoma | |||
1.1. Squamous cell carcinoma | 92 (1.05) | 0.03 | 0.03 (0.02–0.03) |
1.2. Other specified carcinoma | 670 (7.65) | 0.26 | 0.19 (0.17–0.21) |
2. Neuroendocrine tumor (NET) | |||
2.1. NET | 5,932 (67.72) | 2.36 | 1.69 (1.65–1.73) |
2.2. Neuroendocrine carcinoma | 834 (9.52) | 0.33 | 0.24 (0.21–0.26) |
3. Sarcoma | |||
3.1. Sarcoma | 21 (0.24) | 0.01 | 0.01 (0.00–0.01) |
3.2. Leiomyosarcoma | 32 (0.37) | 0.01 | 0.01 (0.01–0.01) |
3.3. Other specified sarcoma | 41 (0.47) | 0.02 | 0.01 (0.01–0.01) |
4. Gastrointestinal stromal sarcoma | 202 (2.31) | 0.08 | 0.06 (0.05–0.07) |
5. Melanoma | 52 (0.59) | 0.02 | 0.01 (0.01–0.01) |
6. Lymphoma | 884 (10.09) | 0.35 | 0.25 (0.25–0.26) |
CR, crude rate per 100,000; ASR, age-standardized incidence rate; CI, confidence interval.
The number of patients and incidence of colorectal nonadenocarcinoma in female
Histologic category | No. (%) | Rate |
|
---|---|---|---|
CR | ASR (95% CI) | ||
Total malignancy of colon and rectum | 106,775 (100) | 42.58 | 25.03 (24.87–25.18) |
Nonadenocarcinoma patients | 5,735 (5.37) | 2.29 | 1.56 (1.52–1.60) |
1. Carcinoma | |||
1.1. Squamous cell carcinoma | 196 (3.41) | 0.08 | 0.05 (0.05–0.05) |
1.2. Other specified carcinoma | 496 (8.64) | 0.20 | 0.13 (0.13–0.14) |
2. Neuroendocrine tumor (NET) | |||
2.1. NET | 3,653 (63.70) | 1.46 | 1.03 (1.00–1.06) |
2.2. Neuroendocrine carcinoma | 500 (8.72) | 0.20 | 0.14 (0.13–0.14) |
3. Sarcoma | |||
3.1. Sarcoma | 14 (0.24) | 0.01 | 0.00 (0.00–0.00) |
3.2. Leiomyosarcoma | 24 (0.42) | 0.01 | 0.01 (0.00–0.01) |
3.3. Other specified sarcoma | 24 (0.42) | 0.01 | 0.01 (0.00–0.01) |
4. Gastrointestinal stromal sarcoma | 191 (3.33) | 0.08 | 0.05 (0.04–0.06) |
5. Melanoma | 90 (1.57) | 0.04 | 0.02 (0.02–0.03) |
6. Lymphoma | 547 (9.54) | 0.22 | 0.15 (0.14–0.15) |
CR, crude rate per 100,000; ASR, age-standardized incidence rate; CI, confidence interval.
Patient number and percentage of colorectal nonadenocarcinoma by age
Histologic type | Age (yr) |
|||||||
---|---|---|---|---|---|---|---|---|
0–19 | 20–29 | 30–39 | 40–49 | 50–59 | 60–69 | 70–79 | ≥ 80 | |
Total malignancy of colon and rectum | 207 (100) | 1,256 (100) | 7,550 (100) | 25,354 (100) | 59,936 (100) | 73,702 (100) | 70,088 (100) | 29,049 (100) |
Nonadenocarcinoma patients | 101 (48.79) | 424 (33.76) | 2,061 (27.30) | 3,530 (13.92) | 3,991 (6.66) | 2,531 (3.43) | 1,480 (2.11) | 377 (1.30) |
1. Carcinoma | ||||||||
1.1. Squamous cell carcionma | 2 (1.98) | 1 (0.24) | 6 (0.29) | 33 (0.93) | 66 (1.65) | 68 (2.69) | 74 (5.00) | 38 (10.08) |
1.2. Other specified carcinoma | 1 (0.99) | 7 (1.65) | 41 (1.99) | 123 (3.48) | 240 (6.01) | 305 (12.05) | 311 (21.01) | 138 (36.60) |
2. Neuroendocrine tumor (NET) | ||||||||
2.1. NET | 34 (33.66) | 326 (76.89) | 1,709 (82.92) | 2,759 (78.16) | 2,828 (70.86) | 1,415 (55.91) | 471 (31.82) | 43 (11.41) |
2.2. Neuroendocrine tumor | 6 (5.94) | 31 (7.31) | 164 (7.96) | 316 (8.95) | 383 (9.60) | 235 (9.28) | 166 (11.22) | 33 (8.75) |
3. Sarcoma | ||||||||
3.1. Sarcoma | 2 (1.98) | 1 (0.24) | 10 (0.49) | 3 (0.08) | 6 (0.15) | 8 (0.32) | 4 (0.27) | 1 (0.27) |
3.2. Leiomyosarcoma | 1 (0.99) | 0 (0) | 4 (0.19) | 7 (0.20) | 15 (0.38) | 16 (0.63) | 10 (0.68) | 3 (0.80) |
3.3. Other specified sarcoma | 0 (0) | 0 (0) | 1 (0.05) | 22 (0.62) | 16 (0.40) | 14 (0.55) | 17 (1.15) | 4 (1.06) |
4. Gastrointestinal stromal sarcoma | 0 (0) | 4 (0.94) | 20 (0.97) | 64 (1.81) | 109 (2.73) | 101 (3.99) | 80 (5.41) | 15 (3.98) |
5. Melanoma | 0 (0) | 1 (0.24) | 5 (0.24) | 12 (0.34) | 24 (0.60) | 33 (1.30) | 52 (3.51) | 15 (3.98) |
6. Lymphoma | 55 (54.46) | 53 (12.50) | 101 (4.90) | 200 (5.67) | 304 (7.62) | 336 (13.28) | 295 (19.93) | 87 (23.08) |