Pathological Spectrum of Pediatrics Teratoma a 5 Year Study among Sudanese Pediatrics Patients

Pathological Spectrum of Pediatrics Teratoma a 5 Year Study among Sudanese Pediatrics Patients

Safeya Ahamed Mohamed Tamim Elder*1, Dr. Sawsan Abdel Rahim2, Dr. Nadia I. A. ALdawi3

1. Saudi Arabia makkha.

2. Faculty of Medicine, University of Khartoum.

3. Hamburg, Germany.

*Correspondence to: Safeya Ahamed Mohamed Tamim Elder, Saudi Arabia makkha.


© 2024 Safeya Ahamed Mohamed Tamim Elder This is an open access article distributed under the Creative Commons Attribution  License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Received: 21 February 2024

Published: 01 April 2024


Background: Teratomas are embryonal neoplasms consisting of tissues from at least two of the three germ layers. Teratomas can occur in almost any region of the body and in any organ, but they are most commonly observed in the paraxial and midline locations.

Objective: To study of histological variants of teratomas among Sudanese pediatrics patients

Materials and Methods: The present study is a retrospective study conducted in Soba university  Teaching Hospital  and  national public health laboratory khartoum . All the cases (less than 16 years) diagnosed as teratoma in the period of 8 years were included and studied with reference to age, sex, presenting clinical features, site, gross, and microscopic features.

Results: A total of 60 pediatric cases were reviewed, 49(82%) were females and 11(18%) were males. Site of origin was ovaries in 46.7%, Sacrococcygeal in 25%, abdomen in 8.3%, head and neck in 6.7%, chest in 3.3% and 1.7% in testis. Mature teratomas account for 81.7%, mixed in 13.3% and 5% were immature teratoma. Altman class-I was the main classification in 8 (53.3%) of sacrococcygeal teratoma cases. Immature teratoma Grade-3 was predominant among 5(62.5%). All three germ layers (Ectoderm, mesoderm and endoderm) were the main mature components in 43(82.7%) patients with mature teratomas, and neural tissues were the main components of immature teratomas in 5(71.4%) patients. the majority of sacrococcygeal teratoma cases were females (60%), below one year age (60%) and mature in histological classification (60%).

Conclusion: Teratomas have much diversity in their age at presentation, location, gross features, and in degree of differentiation

Pathological Spectrum of Pediatrics Teratoma a 5 Year Study among Sudanese Pediatrics Patients


Teratoma is a special type of mixed tumor that contains recognizable mature and immature cells or tissues derived from one or more of the three primordial germ cell layers.(1) The word teratoma is derived from the Greek word “teras,” meaning monster or deformed and “oma” means tumor. Virchow coined the term “teratoma” in his book on tumors published in 1863.(2)

Teratomas originate from totipotential germ cells such as those normally present in the ovary and testis and sometimes abnormally present in sequestered midline embryonic rests.(1) Thus, they are common in gonads and in midline or paraxial location. Teratomas are common in children but can occur in all ages. Teratomas display wide range of differentiation from most primitive elements on one end to highly organize axial and metamaric structures such as fetus-in-fetu at other end.(3)

Teratomas arise from three germ cell layers, the ectoderm, endoderm and mesoderm, and have several degrees of differentiation and may be malignant, benign or something mixed. One of the most common anatomic regions for teratoma in the pediatric population is the saccrococyx (57%), along with other anatomic regions such as retroperitoneal, mediastinum, intracranial, cervical and gonads. Teratomas also can be seen at other parts of body including the GI tract, head & neck and spinal cord. The prognosis of this disease is very variable. Early diagnosis and treatment of this kind of tumor is of great importance since it could experience malignant transformation and invasion. We report our experience with teratomas at a tertiary pediatric surgery center (4).

Teratomas are histologically classified as either mature or immature, with the immature elements, consisting principally of primitive neuroglial tissue and neuroepithelial rosettes (5,6). In a minority of immature teratomas, malignant elements, predominantly yolk sac tumor or embryonal carcinoma, may be present (5). Immature elements are common in fetal teratomas, yet their presence does not carry the same poor prognosis that it does later in life. The immature histologic appearance may be more reflective of the immaturity of the fetus and not necessarily reflective of the biologic behavior of the tumor. The location and size of the mass are far more important than the histologic grade for predicting outcome. Fully resectable, immature teratomas in the newborn have a generally favorable prognosis (7).


1.2Justification and problem statement

Teratomas are the second most common neoplasm in children following yolk sac tumour and occur with a relative frequency ranging from 13 to 19% (8,9). Teratomas can occur in almost any region of the body and in any organ, but they are most commonly observed in the paraxial and midline locations. Although benign teratomas at different sites of the body share common histological features, they behave differently. Their incidence in terms of site and sex varies widely, as does their prognosis, which depends on several factors, including site, age at operation, resectability, histological features and stage. According to the best knowledge of the researcher, there are no published works aimed to evaluate clinicohistological features of teratomas in Sudan.  Therefore, this research may provide valuable information that can shed a light in this problem among Sudanese children with teratoma.


2. Methodology

2.1 Study design: A retrospective study

2.2. Study area: The study was conducted in Soba Teaching hospital is one of the largest referral hospital in Sudan the hospital receive patients from all states and localities of Sudan as well as from all hospitals in Khartoum state

2.3. Study duration: The study was conducted in the period from 2010 to 2018

2.4. Study population: Study enrolled pediatrics  cases of teratomas (up to 16 years age) presented to Soba Hospital Lab and National Public Health Laboratory from 2010-2018.

2.4.1. Inclusion criteria:

  • Pediatrics patients up to 16 age
  • All Sudanese tribes
  • Both sexes
  • Patient with full records information and blocks

2.4.2. Exclusion criteria:

  • Patients  above 16 year of age
  • Patients with incomplete information or missed block

2.5. Sample size

Total coverage of all pediatric teratoma patients verified the inclusion criteria during the study period.

2.6. Data collection tools and methods:

Data collected from paraffin embedded blocks, the histological sections were obtained and stained with hemotoxylin and eosin, and then slides of histological sections were examined under microscope by the supervisor histopathologist and principle researcher, the clinical information of patients obtained from the records of the lab by request forms. The data gathered by using specific data sheet composed of; to age, sex, presenting clinical features, site, gross, and microscopic features.

2.7. Data analysis:

Data analyzed by using Statistical Package for Social Studies Program (SPSS, V. 21.0. IBM; Chicago). The analyzed data presented in tables and figures designed by Microsoft Excel 2007. Chi-square test was used as significance test and P. values considered as significant at level 0.05.

2.8 Ethical consideration:

An ethical approval was obtained from Faculty of Medicine, University of Khartoum


3. Results

In total 60 children with teratoma enrolled in the present study, 49(82%) were females and 11(18%) were males (F:M= 4.6:1) (figure 3.1).

One-third of the children (n= 20; 33.3%) were found in age group from 11 – 16 years, 16(26.7%) in age group below one year, 14(23.3%) in age group form 6 – 10 years and 10(16.7%) of the patients found in age group from 1 – 5 years (figure 3.2)

In the sites of teratoma, the majority of the patients 28(46.7%) had teratoma in ovary, 5(8.3%) in pelvic, also 5(8.3%) in abdomen, 4(6.7%) in head and neck, 2(3.3%) in chest and one (1.7%) patient in testis. Additionally, Sacrococcygeal teratoma was presented in 15(25%) of the participants (table 3.1, figure 3.3)

In respect to Altman classification among Sacrococcygeal teratoma children, type-1 class was the main classification in 8 (53.3%) of them followed by type-2 class in 4(26.7%) and type-3 class in 3(20%) patients (table 3.2)

Mass was the most common clinical presentation in 46(76.7%) teratoma children, abdominal pain in 11(18.3%), intestinal obstruction in 2(3.3%) and Undiscerning testes in one (1.7%) patient (table 3.3)

Excisional biopsy collection was performed for 57(95%) of the children and incisional for three (5%) cases (table 3.4) 

Cystic gross appearance was encountered in the most of the patients 45(75%), solid gross in 14(23.3%) and soft piece in one (1.7%) patient (table 3.5)

According to the histological classification, mature teratoma was encountered in 49(81.7%) children followed by mixed type in 8(13.3%) and immature teratoma in 3(5%) of them (figure 3.4)

All three germ layers (Ectoderm, mesoderm and endoderm) were the main mature components in 43(82.7%) patients followed by ectoderm and mesoderm in 7(13.5%), ectoderm and endoderm in 1(1.9%) and also ectoderm in 1(1.9%) patient (table 3.6)

Among immature teratoma, Grade-3 was the presented in the most of the children with immature teratoma 5(62.5%), Grade-2 in 2(25%) and Grade-1 in one (12.5%) patient (table 3.7)

In immature tissue components, Neural tissues were comprised in 5(71.4%) patients and neural with cartilage and bone in 2(28.6%) (table 3.8)

Mixed teratoma with yolk sac was presented in 7(87.5%) and with choriocarcinoma in 1(12.5%) patient (table 3.9)

Alpha feto-protein among the children with immature teratoma was not specified in 10(90.9%) patients and not performed in (10.1%) patient (table 3.10)

Likewise, metastasis among the children with immature teratoma was not specified in 10(90.9%) patients and absent in (10.1%) patient (table 3.11)

As showed in figure 3.5; sacrococcygeal teratoma was presented in 9(60%) girls and 6(40%) boys. The difference was statically significant (P= 0.021)

Figure 3.6 showed that, sacrococcygeal teratoma was predominant among the children in age group below one year 9(60%) (P= 0.002).

Also, sacrococcygeal teratoma was mature in 9(60%), mixed in 5(33.3%) and immature in 1(6.7%) child (P= 0.027) (figure 3.7).

Figure 3.1: the distribution of the gender among the children with teratoma (N= 60)

Figure 3.2: the distribution of the age among the children with teratoma (N= 60)

Table 3.1:The sites of teratoma in the children with teratoma (N= 60)

Figure 3.3: Sacrococcygeal teratomas among the children with teratoma (N= 60)

Table 3.2: Altman classification among saccrocoxgeal teratoma children (N= 14)

Table 3.3:Clinical presentation of the children with teratoma (N= 60)

Table 3.4: Types of biopsy among the children with teratoma (N= 60)

Table 3.5: Gross appearance of the samples obtained from children with teratoma (N= 60)

Figure 3.4: histological classification of the children with teratoma (N= 60)

Table 3.6: Distribution of mature components among the children with teratoma Contain mature and 3 patients with mixed teratoma

Table 3.7: Immature teratoma grading among the children participated in the study

Table 3.8: Immature tissue components among the children with immature teratoma

Table 3.9:Mixed teratoma components among the children

Table 3.10: Alpha feto-protein among the children with immature teratoma

Table 3.11:Metastasis among the children with immature teratoma

Figure 3.5: distribution of sacrococcygeal teratoma according to the genders of the children (N= 15)

Figure 3.6: distribution of sacrococcygeal teratoma according to the age of the children (N= 15)

Figure 3.7: distribution of sacrococcygeal teratoma according to the histological classifications (N= 15)

Please click here to view all tables and figures


4. Discussion, Conclusion & Recommendations

4.1. Discussion

Teratomas are tumors that arise from germ cells that fail to mature normally in the gonadal locations and several cases were found in extra gonadal regions. Teratoma is the most common germ cell tumor in childhood (10). The findings in this study show that majority of teratoma cases occurred in the females more than males (82% vs. 18%). This corroborates other study conducted by Umar M. et al who reported 25 (64.1%) of teratoma patients were females and 14 (35.9%) were male, Bezuidenhout J. et al who reported teratomas were commonly presented among females than males with female-to-male ratio (5.5:1), and Grosfeld JL. et al who reported, teratomas were observed in (68%) of the girls and 27 (32%) of the boys.

This study also showed that, the children in age group from 11-16 years (33.3%) were more affected by teratomas than the other. This result was in agreement with other studies.

The most common complaint in our study group was palpable mass (76.7%) followed by pain in abdomen (18.3%). These in accordance with the study performed by Varma AV. et al, Deodhar et al and Ayhan et al.

Ovary was the most common site of teratoma in the present study (48.3%) similar to Bezuidenhout J, et al and Varma AV. et al.However, in studies conducted in infants and children, ovary was the second most common site of teratoma after the sacrococcygeal region (6).

Our study demonstrated that, the one-quarter (n= 15; 25%) of the children had sacrococcygeal teratoma which is lower than the range of literature (35-60%) (44). Also, our frequency was much lower as compared to the studies of Umar M. et al (43.6%) Grosfeld JL. et al (64.8%) and higher than the study of Varma AV. et al (7.61%). These variations might be attributed to the differences in geographical areas, sampling and sample size and also other factors like genetics and biological factors.

Regarding Altman distribution of sacrococcygeal teratoma, most common type was Type I (53.3%).This was comparable with the studies of Roopali D. et al and Kournaloo J et al.

The frequency of abdominal and chest in our study were 8.3% and 3.3%, respectively, which was compared to Issacs H. et al who reported, teratomas involving the chest and abdomen are relatively uncommon, collectively representing less than 10% of fetal teratomas (9). 

The head and neck teratoma was presented in 6.7% of the cases which is consistent with that mentioned in literature; head and neck regions are relatively uncommon site of teratomas (7).

Generally, testicular teratoma in infancy and childhood is uncommon accounted for only 4-9% of all testicular tumors. The current study showed testicular teratoma was presented in only one (1.7%) child, similarly, Varma AV. et al reported testicular teratoma in one (3.26%) case (82). in the study of Bezuidenhout J et al testicular teratomas were absent.

Teratoma can be divided into either cystic or solid. Cystic teratomas are mostly benign, containing sebaceous materials and mature tissue types (14). In this study cystic teratomas were predominant than solid type (75% vs. 20%). 

Mature teratoma is the most common in this study (81.7%) followed by mixed (13.3%) and immature teratoma in (5%). These findings were in agreement with previous studies as by Umar M. et al who reported mature teratomas account for 82.0% while 18.0% were immature teratoma, Bezuidenhout J et al who reported mature teratomas account for 60.5% while 39.5% were immature teratoma, Terenziani M et al who reported 68.5% mature and 31.5% immature teratomas. Also, Sathyanarayana K. et al reported mature teratomas countered in 67.4% and immature teratomas in 9.6% .

All three germ layers (Ectoderm, mesoderm and endoderm) were the main mature components in 82.7% cases. This in accordance with the study conducted by Varma AV. et al.

According to the criteria of Norris et al. (44) of immature teratoma classification our study revealed; Grade-3 immature teratoma was the presented in 62.5%, Grade-2 in 25% and Grade-1 in 12.5%. These corroborates Heifetz S. et al study who found 47% grade 3, 29% grade 2, 24% grade 1 (85). However, Deodhar KK et al represented 13 were stage I, 3 were stage II and 7 were stage III immature teratoma (89), this could be referred to study population difference as we conducted our study in all types of teratomas whilst Deodhar KK et al performed it in only ovarian immature teratomas.

Regarding immature tissue components, neural tissues were presented in most case of immature teratomas 71.4%. Our finding was comparable with Deodhar KK et al and Varma AV. et al.

The current study demonstrated that, yolk sac tumor was presented in the vast majority of cases with mixed teratomas (87.5%). This goes in same line with the study of Heifetz S. et al who mentioned yolk sac components were present in most mixed teratomas. Also, Sathyanarayana K. et al reported that 9 out of 12 (75%) of the cases had mixed teratomas with yolk sac.

Tumor markers are of value in the diagnosis, monitoring of disease progress and efficacy of treatment as well as detection of metastasis particularly in malignant cases. Immature teratomas cause a rise in serum levels of tumor markers alpha-fetoprotein and carcinoembryonic antigen (10). Unfortunately, tumor marker assays (alpha-fetoprotein) were not specified in most cases (88.9%) which were negatively reflected in follow-up of metastasis specification among also the vast majority of our cases.

This study illustrated that, females were commonly affected by sacrococcygeal teratoma when compared to males. Additionally, the most common age of presentation was below one year of age (60%). Our findings were consistent with other literature. Roopali D. et al study noticed that female preponderance (70% vs. 30%) and boys with the age ranges from 2 months to 18 months. Majority of the cases were less than 3 months.

In the demonstrated study, majority of cases on histological evaluation were documented as mature teratoma constituting about 60% which corroborates other studies.


4.2 Conclusion

The present study concluded the following points:

  • Females and age group from 11-16 years reported more incidences of teratomas.
  • Ovaries and sacrococcyx were the main sites of teratomas among Sudanese children.
  • Palpable masses and abdominal pain were the most common presenting features
  • Teratomas were commonly presented as cystic in gross appearance. Histologically, mature teratomas were predominant. 
  •  All germ layers (Ectoderm, mesoderm and endoderm) were the main mature teratoma components, and neutral tissues were the main immature teratoma components.
  • Sacrococcygeal teratomas were mostly tended to be mature, affected females and age below one year patients.


 4.3 Recommendations

  • Although teratoma considered as a rare but also fatal and early diagnosis is important and crucial.
  • Evaluation of serum tumor markers (e.g. alpha-fetoprotein) is extremely needed in diagnosis and follow-up 
  • High quality prospective multi-institutional studies are required in order to get an objective insight into biology and prognostic factors of teratomas in children.



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