Background
Methods
Tissue collection and clinical data
Immunohistochemical staining
Statistical analysis
Evaluation of the literature
In patients with gonadal dysgenesis, is there a predictive role of immunohistochemical markers in the detection of germ cell malignancy?
Results
Patient | Age | Diagnosis | Sex assignment (M/F) | Karyotype | Gonadal location | EMS out of 12 | Malignancy | Gonadal tissue type | OCT 3/4 | PLAP | Β-Catenin | AFP | CD117 |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | 6 y | XY PGD | F | 45,X[16]/46,X + mar[4], SRY positive | Abdomen | 1 | No | Streak | - | - | ++C | - | +C |
2 | 11 y | XY PGD | F | 45,X/46,XY | Abdomen | 1 | No | Streak | - | - | ++C | - | +C |
3 | 12 y | XY PGD | F | 45,X/46,XY | Abdomen | 1 | No | Streak | - | - | ++C | - | - |
4 | 16 y | XY PGD | F | 45,X[11]/46, X, idic (Y) (q11.21) | Abdomen | 1 | No | Streak | - | - | ++N | - | - |
5 | 7 m | XY PGD | M | 45, X/46, XY | L- abdomen | 8.5 | No | Streak | - | - | ++C | - | - |
R- scrotum | |||||||||||||
6 | 7 m | XY PGD | M | 45, X/46, XY | L-Scrotum | 11.5 | No | Streak | - | - | ++C | - | - |
R-abdomen | |||||||||||||
7 | 4 m | XX PGD | M | 46, XX | Inguinal | 3 | No | O/T | +C, T & O | - | ++C, T & O | - | +C, T |
++C, O | |||||||||||||
8 | 6 m | XX PGD | M | 46, XX | Inguinal | 4 | No | O/T | +C, T & O | - | ++C, T & O | - | +C, T |
++C, O | |||||||||||||
9 | 2 y | XX PGD | M | 46, XX | Inguinal | 5 | No | O/T | +C, T & O | - | -T | - | -T |
++C, O | ++C, O | ||||||||||||
10 | 5 m | XY PGD | M | 46, XX/46, XXY | L-scrotum | 6 | No | O/T | ++N, T | ++C, T | ++C, T & O | - | ++C, T & O |
R- abdomen | |||||||||||||
+C, O | -O | ||||||||||||
11 | 8 m | XY PGD | M | 46, XY with mosaicism for 45, X/46, XY in 40 % of cells | L- abdomen R- scrotum | 6.5 | No | O/T | - | - | ++C | ++C | +C |
12 | 9 y | XY PGD | M | 46, XY/47, XXY/45,X | Abdomen | 8 | No | O/T | - | - | ++C | - | -T |
+C, O | |||||||||||||
13 | 14 m | XX PGD | M | 46, XX | L- inguinal | 8.5 | No | O/T | ++N | ++C | ++C | - | ++C |
R- scrotum | |||||||||||||
14a | 12 m | XY PGD | M | 45, X/46, XY | R abdomen | 8 | No | O/T | ++N | ++C | ++C | - | ++C |
14b | 33 m | XY PGD | M | 45, X/46, XY | L-scrotal | 8 | No | Dysgenetic Testis | +N | - | ++C | - | +C |
15 | 15 y | XY PGD | F | 46, XY and gain of chrom 16p11.2 | Inguinal | 2 | No | Dysgenetic Testis | - | - | +C | - | - |
16 | 2 m | XY PGD | F | 45, X/46, XY | Abdomen | 4 | No | Dysgenetic Testis | ++N | ++C | ++C | - | ++C |
17 | 22 m | XY PGD | F | 45, X/46, XY | Inguinal | 5 | No | Dysgenetic Testis | ++N | ++C | ++C | - | +C |
18 | 4 y | XY PGD | F | 46, XY with gain of chrom 2q14.1 | Inguinal | 5 | No | Dysgenetic Testis | - | - | ++C | - | - |
Patient | Age | Diagnosis | Sex assignment (M/F) | Karyotype | Gonadal location | EMS out of 12 | Malignancy | Gonadal tissue type | OCT 3/4 | PLAP | Β-Catenin | AFP | CD117 |
19 | 16 y | XY PGD | F | 46, XY | Inguinal | 5 | No | Dysgenetic Testis | +C | - | ++C | - | +C |
20 | 11 m | XY PGD | M | 46, XY | Inguinal | 6 | No | Dysgenetic Testis | - | - | - | - | - |
21 | 6 m | XY PGD | M | 46, XY | L-scrotum | 9 | No | Dysgenetic Testis | ++N | ++C | ++C | - | ++C |
R- abdomen | |||||||||||||
22 | 20 m | XY PGD | M | 45, X/46, XY | Inguinal | 9 | No | Dysgenetic Testis | - | - | ++C | - | - |
23 | 7 m | XY PGD | F | 46, XY, t(11;16)(q22.1;q12.2) | Abdomen | 1 | GB-like | GB-like arising from immature testicular tissue | ++N | ++C | ++C | - | ++C |
24 | 11 m | XY PGD | M | 46, XY | L- abdomen | 9.5 | L gonad- GB | GB arising from streak-like ovarian tissue | ++N | ++C | ++C | - | ++C |
R- scrotum | |||||||||||||
25 | 17 y | XY CGD | F | 46, XY | Abdomen | 1 | GB with DG | DG and GB arising from steak gonad with Ovarian stroma | ++N | ++C | ++C | - | ++C |
26 | 18 y | XY CGD | F | 46, XY | Abdomen | 1 | R ovary- GB & DG | GB and DG arising from streak gonad with Ovarian stroma | ++N | ++C | ++C | - | ++C |
L ovary- GB |
Tumor markers | Sensitivity (95 % CI) | Specificity (95 % CI) | Positive predictive value given prevalence of gonadal malignancy as 15-40 % |
---|---|---|---|
OCT 3/4, PLAP, and CD117 combined | 100 % (40.2-100 %) | 73.9 (51.6-89.7 %) | 40.3-71.9 % |
OCT 3/4 | 100 % (40.2-100 %) | 52.2 % (30.6-73.1 %) | 26.9-58.2 % |
PLAP | 100 % (40.2-100 %) | 73.9 % (51.6-89.7 %) | 40.3-71.9 % |
Β-catenin | 100 % (40.2-100 %) | 4.4 % (0.7-22.0 %) | 15.6-41.1 % |
CD117 | 100 % (40.2-100 %) | 34.8 % (16.4-57.3 %) | 21.3-50.6 % |
AFP | 0 % (0-59.8 %) | 95.7 % (78.0-99.3 %) | 0 % |
Literature review: evidence and recommendations
In patients with GD, is there a predictive role of immunohistochemical markers in the detection of germ cell malignancy?
Evidence
Quality assessment | Summary of findings | Quality | |||
---|---|---|---|---|---|
Author | Study design and objective | Design limitations | Sample | Results/Conclusions | |
Inconsistency of results | |||||
Indirectness of evidence | |||||
Palma (2013) | Retrospective Observational Study | Insufficient sample size | 18 gonadal samples from 15 pediatric patients with 45,X/46,XY PGD | 1 patient had GB, 1 patient had DG | Low |
To determine whether OCT 3/4 and β-Catenin are expressed in dysgenetic gonads before GB development and whether TSPY participates in malignant invasive behavior | No inconsistencies | Ages not specified | 14/18 samples stained + for OCT 3/4 | ||
Head-to-Head comparison in correct population | Only 3 samples stained + for β-catenin | ||||
-Seen in Dysgenetic testes, UGT, GB, and DG, not + in streak tissue or mature germ cells | |||||
Tissue expressing OCT 3/4 and TSPY is associated with a high risk for GB development. | |||||
Suggest that β-catenin is not involved in dysgenetic gonad progression to GB, participates after GB is established. | |||||
Barros (2011) | Retrospective Observational Study | Insufficient sample size | 32 gonadal samples from 16 patients with Turner Syndrome and Y chromosome material | 19 % had + nuclear OCT4 staining, suggesting the presence of germ cell tumor cells (likely GB or CIS) | Low |
To investigate the frequency of gonadal tumors among patients with Turner syndrome and Y-chromosome material | No inconsistencies | Ages 8–18 yrs. | OCT4 immunohistochemistry is more sensitive than conventional H&E staining to indicate the risk of development of germ cell tumors in TS patients | ||
Head-to-Head comparison in correct population | |||||
Palma (2008) | Retrospective Observational Study | Insufficient sample size | 7 patients with PGD and GB | OCT 3/4 was + in the nuclei of immature germ cells in GB | Low |
To evaluate the participation of β-catenin and OCT 3/4 in the oncogenic pathways involved in the transformation of GB into seminoma/DG | No inconsistencies | Ages 2–33 m | Β-catenin was overexpressed in immature germ cells in GB | ||
Head-to-Head comparison in correct population | Β-catenin and OCT 3/4 co-localized in immature germ cells in GB nests in all cases | ||||
The proliferation of immature germ cells in GB may be due to an interaction between OCT 3/4 and accumulated β-Catenin in the nuclei of the immature germ cells | |||||
Cools (2006) | Retrospective Observational Study | Insufficient sample size | 60 gonadal samples from 43 patients with GD | Incidence of GCTs was 35 % | Low |
To define the histological origin of GB, allowing the identification of high-risk patients | No inconsistencies | Ages 1 m-25 yrs. | Germ cells within GB were + for OCT 3/4, c-KIT, PLAP, and TSPY | ||
Head-to-Head comparison in correct population | In UGT found adjacent to GB, OCT 3/4, PLAP, and c-KIT + germ cells were found | ||||
A gonadal biopsy revealing the presence of UGT with OCT 3/4 + cells on the basal lamina contains high risk for GCT and should lead to gonadectomy. | |||||
Quality assessment | Summary of findings | Quality | |||
Author | Study design and objective | Design limitations | Sample | Results/Conclusions | |
Inconsistency of Results | |||||
Indirectness of Evidence | |||||
Cools (2005) | Retrospective Observational Study | Insufficient sample size | 58 gonadal samples from 30 patients with undervirilization syndromes | OCT 3/4 was found in all patients <9 m of age | Low |
To distinguish germ cells with maturation delay from those with CIS | Different populations (not looking specifically at GD patients) | Ages 1 m-23 yrs. | -In young patients and controls, OCT 3/4 + cells were found centrally in the tubule | ||
-In 3 older patients with CIS, OCT 3/4 + cells were found along the basal lamina | |||||
Expression of PLAP and c-KIT was similar to OCT 3/4, but less consistent | |||||
The presence of germ cells + for OCT 3/4, PLAP, or c-KIT in patients < 1 yr is in accordance with expected maturation delay and is insufficient for the diagnosis of CIS. | |||||
The location of OCT 3/4 positive cells is important in differentiating between CIS and maturation delay | |||||
Kersemaekers (2005) | Retrospective Observational Study | Insufficient sample size | 6 gonads from 5 patients with GD containing GB | 4 patients had DG arising from GB | Low |
To investigate the pathogenesis of GB and evaluate its relationship to CIS. | No inconsistencies | ||||
Head-to-Head comparison in correct population | Ages 14–21 yrs. | c-KIT was the least consistent marker | |||
PLAP was + in all GBs and adjacent invasive components. | |||||
Most of the tumor cells in invasive DG were weakly + or - for PLAP. | |||||
OCT 3/4 was + in all GBs and DGs | |||||
Seen in more immature cells, not mature cells | |||||
The development of an invasive germ cell tumor seems to involve selection and clonal expansion of an immature germ cell + for OCT 3/4 and TSPY | |||||
Slowikowska-Hilczer (2001) | Retrospective Observational Study | Insufficient sample size | 23 patients with XY GD | On the basis of PLAP expression, CIS was detected in 10 cases (43.5 %) with GD. | Low |
Ages 3 m-7 yrs. | GB was found in 4 cases of GD and DG was found in 1 patient with GD (17 years old) | ||||
No inconsistencies | |||||
To investigate the appearance of CIS in patients with 46,XY testicular dysgenesis in different ages and in adult patients from other groups | |||||
Head-to-Head comparison in correct population | |||||
Results showed a high prevalence of CIS in XY GD, indicating the importance of early histopathological evaluation of the gonads in these patients |
Recommendations
Discussion
Present study | Previous studies | |
---|---|---|
Prevalence of germ cell tumor in GD population | 11.5 % | 15-40 % |
Age | 7 m - 18 y | Wide age range at presentation. GB has been identified in cases < 1 yr of age. |
Location of gonads in patients with malignancy | 100 % in abdomen | Abdominal gonads have been shown to have highest risk of malignant transformation. |
Degree of virilization in patients with malignancy | 3 of 4 pts were phenotypic female. | Low risk: Normally virilized males |
1 pt was ambiguous. | Intermediate Risk: Mild undervirilization | |
High Risk: Ambiguous genitalia | ||
Gross pathology findings | 3 pts had GB arising from streak gonad with ovarian stroma. | Low Risk: Streak gonad without germ cells, ovary, testis without immature germ cells |
1 pt had GB arising from immature testicular tissue. | High Risk: Undifferentiated gonadal tissue, dysgenetic testicle | |
Immunohistochemistry | All pts with GCT had strong expression of OCT 3/4, PLAP, β-catenin, and CD117 | OCT 3/4, PLAP, β-catenin, and CD117 are established markers of germ cell malignancy. |