Figure 22-47 Histogenesis and interrelationships of tumors of germ cell origin. CSBRP-July-2012
Germ cell tumorsHence germ cell tumors can be divided into: 1-Those that continue to resemble germ cells ex: Seminoma / Dysgerminoma 2-Those that resemble protions of the embryo ex: Teratomas 3-Those that resemble portions of the extraembryonic tissue ex: Yolk sac tumor, Choriocarcinoma CSBRP-July-2012
Seminoma•Most common type of germ cell tumor•Peak in 30s•Types: classic type, spermatocytic type, anaplasitc type.•Spermatocytic seminoma: distinct both clinically,histologically, Uncommon >60yrs No metastasis (excellent prognosis) CSBRP-July-2012
Special features of Spermatocytic Seminoma• Do not arise from intratubular germ cell neoplasm• Uncommon 1-2% of all testicular tumors• Occurs in old age >60yrs• Slow growing; No mets to regional lymphnodes• Surgery is the mode of Tx• No lymphocytic infiltration• Three types of cells in histology• Excellent prognosis CSBRP-July-2012
Here is an embryonal carcinoma of the testis. There is a rim of normal testis superiorly.The tumor is soft and much more variegated than the seminoma, with red to tan tobrown areas, including prominent hemorrhage and necrosis
Embryonal carcinoma, but there are scattered firmer white areas thathistologically are teratoma. Thus, this testicular neoplasm is mixed embryonal carcinoma plus teratoma (sometimes called teratocarcinoma).
This is the histologic pattern of embryonal carcinoma. Sheets of blue cells are trying to form primitive tubules.
Teratoma• Infants and young children• In adults pure teratomas are rare• Gross: Large, heterogenous areas Cystic and solid areas• Micro: collection of tissue derived from different germ layersTerms:1. Teratoma with malignant transformation2. Teratocarcinoma CSBRP-July-2012
A small testicular carcinoma is shown here. There is a mixture of bluish cartilage (Bluearrow) with red and white tumor tissue. This neoplasm microscopically containedmainly teratoma, but areas of embryonal carcinoma were also present.
Here is an embronal carcinoma mixed with teratoma in which islands of bluish whitecartilage from the teratoma component are more prominent. A rim of normal browntestis appears at the left. CSBRP-July-2012
Here is a testicular neoplasm that is mostly teratoma, but embryonal carcinoma andseminoma were found microscopically. In contrast with the ovary, pure benignteratomas of the testis are very rare.
At the bottom is a focus of cartilage. Above this is a primitive mesenchymal stroma andto the left a focus of primitive cells most characteristic for embryonal carcinoma. This isembryonal carcinoma mixed with teratoma.
Pathology Pearls “An important point to remember” Testicular Teratoma in Pre-pubertal males: Benign in Post-pubertal males: MalignantThis rule will not apply to OVARIAN teratomas CSBRP-July-2012
Choriocarcinoma• Highly malignant neoplasm• Composed of both cyto and syncytiotrophoblastic cells• Pure form is rare, most common is mixed patterns• Gross: small lesions rarely exceed 5cms, hemorrhages and necrosis are very common• HCG can be demonstrated in syncytiotrophoblasts CSBRP-July-2012
Yolk sac tumor• Also known as infantile embryonal carcinoma or endodermal sinus tumor• It is the most common testicular tumor in infants and children up to 3 years of age• It has a very good prognosis in infants and young children• In adults, the pure form of this tumor is rare; instead, yolk sac elements frequently occur in combination with embryonal carcinoma CSBRP-July-2012
An endodermal sinus tumor (yolk sac tumor) of the testis is shown composed of primitive germcells that form glomeruloid or embryonal-like structures. These tumors are most frequent inchildren, but overall they are rare.
Sertoli cell tumor (Androblastoma)• Functional tumor: may elaborate estrogens or androgens (precocious masculanization or feminization)• Occasionally it may induce gynecomastia• Most of them are benign• ~10% may pursue malignant course• Morphology: firm nodules, g/w to yellow• Histology: cells are arranged in trabaculae and structures resembling spermatic cord. CSBRP-July-2012
Gonadoblastoma• Rare• Tumors composed of Germ cells + stromal elements• Arise in dysgenetic gonads (100%)• In some tumors, germ cell component may become malignant giving rise to an invasive Seminoma CSBRP-July-2012
Testicualr Lymphoma• Most common neoplasm in men >60yrs• At presentation it’s advanced disease• It’s almost always NHL – Diffuse large cell lymphoma• Prognosis is very poor CSBRP-July-2012
Mixed germ cell tumors• ~60% of testicular tumors composed of morethan one pattern• Prognosis is worsened by the presence of anaggressive element CSBRP-July-2012
CF of Testicular tumors• Painless enlargement of the testis• Spread: Lymphatics: Retroperitoneal para-aortic nodes Hematogenous: Lungs, brain, liver. Mets may have different histology• Tumors are divided in to Seminoma and NSGCT• Prognosis depends on --- clinical stage --- histological type• Distant mets if present, usually occur within first 2yrs after Tx. CSBRP-July-2012
Differences between Seminoma and NSGCTs SEMINOMA NSGCTPresentation 70% in stage-I 60% in stage-II, III.Mets LN HematogenousTx Extremely Radioresistant radiosensitivePrognosis Less aggressive More aggressive Good prognosis Poor prognosis CSBRP-July-2012
MarkersBiological: Molecular:• AFP • OCT3/4 gene• hCG • Inactivation X• PAP chromosome• Placental lactogen These can be detected by• LDH immunoperoxidase and PCR CSBRP-July-2012
Value of serum markers (HCG, AFP, LDH)1. In the evaluation of testicular masses2. Staging testicular germ cell tumors3. To assess tumor burden4. To monitor response to Tx and relapse CSBRP-July-2012
Pathology PearlsImportant practical points to remember• All testicular masses are neoplastic, unless proven otherwise• Most of the neoplasms are malignant• No testicular biopsy if tumor is suspected• Hence, in case of solid testicular mass, orchiectomy is performed with a presumption of malignancy• Mets may have different histology: Embryonal carcinoma May present a teratomatous picture in the secondary deposits Explanation: A. Forward and backward differentiation B. Primary tumor is mixed and that minor component in the primary lesion, that were unresponsive to chemotherapy survived resulting in the dominant metastatic pattern CSBRP-July-2012