Do all patients with bilateral testis cancer have a hereditary predisposition?

Intratubular Germ Cell Neoplasia of the Testis, Bilateral Testicular Cancer, and Aberrant Histologies

Intratubular germ cell neoplasia (ITGCN) is a precursor lesion for testicular germ cell tumors, most of which are early stage. ITGCN is also associated with testicular cancer or ITGCN in the contralateral testis, leading to a risk of bilateral testicular malignancy. Testicular biopsy detects most cases, and orchiectomy is the treatment of choice in patients with unilateral ITGCN. Low-dose radiation therapy is recommended in patients with bilateral ITGCN or ITGCN in the solitary testis, but the long-term risks of infertility and hypogonadism need to be discussed with the patient. Rare histologies of primary testicular cancer are also discussed.

Biology of testicular germ cell tumors

Germ cell tumors are derived from cells of the germ cell lineage and are the most common solid malignancies to affect young Caucasian men between the ages of 15 and 40 years. All testicular germ cell tumors develop from the same precursor lesion, intratubular germ cell neoplasia unclassified, which in turn is thought to arise from malignant transformation of a primordial germ cell or gonocyte. These tumors are characterized by extreme chemosensitivity and are considered a model for curative disease. In spite of this, a small subset of patients with metastatic disease fail to achieve a complete response with cisplatin-based chemotherapy or relapse from complete remission. Understanding the molecular biology may help the design of new therapies for those patients with a poor prognosis and could also improve the treatment of cancer in general. Current understanding of the role of genetic and epigenetic factors in the etiology of germ cell tumors and the biochemical mechanisms underlying chemotherapy sensitivity and resistance is discussed in detail in this review.

Increased prevalence of testicular microlithiasis in men with familial testicular cancer and their relatives

Testicular germ cell tumours (TGCT) cluster in families, but responsible genes remain unidentified. The association between testicular microlithiasis (TM) and testicular carcinoma in situ (CIS) suggests that TM may be a TC risk factor. We report testicular ultrasound findings in men with familial TGCT (FTGCT) and their unaffected relatives. A total of 81 men (48 affected and 33 unaffected) from 31 families with > or =2 TC cases underwent testicular ultrasound. Testicular microlithiasis was defined as either 'classic' (> or =5 microliths) or 'limited' (<5 microliths). Statistical analyses used Fisher's exact test and permutation testing. Testicular microlithiasis was more frequent in the contralateral testicles of men with a history of TGCT (affected men) than in unaffected men (48 vs 24%, P=0.04). The association appeared stronger for classic TM (21 vs 9%) than for limited TM (27 vs 15%). Testicular microlithiases were bilateral in six out of seven (87%) unaffected men. Among affected men, TM was not associated with histology, age at diagnosis or cancer treatment. Of the 31 families, 10 accounted for a majority (61%) of the TM cases identified (P=0.11). Testicular microlithiasis was more prevalent among FTGCT family members than described previously in the general population, and was more common among FTGCT cases vs unaffected blood relatives. Testicular microlithiasis appeared to cluster in certain families. These findings suggest both a familial predisposition to TM and an association between TM and FTGCT. If proven, this could be clinically important to men in FTGCT families, and may be useful in identifying specific genes involved in FTGCT.