Intussusception occurs in the small intestine (commonly in the jejunum) in more than 95% of cases.r Cumulative intussusception risk is 15% at age 10 years, 50% at age 20 years, 65% at age 30 years, 77% at age 40 years and 84% at age 50 years.r Polyps greater than 15mm have a higher risk of causing intussusception. Commencing 3 yearly screening for small intestinal polyps from age 8 years is in keeping with international guidelines.rr Screening reduces polyp burden and the likelihood of polyp-related complications such as intussusception.
Video capsule endoscopy (VCE) or magnetic resonance imaging (MRI) are preferred to Barium follow through (BaFT) in PJS patients as the radiation dose is considerably reduced, they detect more polyps that are less than 1cm and they are better tolerated.r
Individuals should be advised to seek emergency medical attention if they have any symptoms suggestive of intussusception/bowel obstruction (e.g. acute onset of vomiting, severe abdominal pain with bloating). Routine haemoglobin testing in children with PJS is not recommended, however may be useful in the symptomatic setting.r
The mechanism of carcinogenesis in PJS remains unknown. Hamartomas are currently not considered precancerous lesions. One study detected no luminal cancers in a small cohort of patients having regular surveillance and polypectomies, raising the possibility that surveillance may reduce colorectal cancer risk.r Further studies are required to evaluate the effect of GI surveillance on the development of GI cancers in PJS.
Breast cancer (female)
Bilateral risk reducing mastectomy can reduce breast cancer risk by at least 90% in high-risk women (including women with PJS).
There is no evidence to date that early detection of breast cancer is associated with better prognosis and survival in females with PJS. Therefore, breast surveillance is based on eviQ high risk breast cancer management guidelines and expert consensus.
MRI is the preferred screening technique due to its high sensitivity. MRI detects smaller tumours which are more likely to be node negative than mammography (MMG). MRI recall rate (requiring further investigation and/or biopsy) is 15% for initial screening, which decreases to less than 10% with subsequent rounds of screening. MMG screening is not recommended before age 40 years in females with PJS.
Tamoxifen and raloxifene have been shown to reduce the risk of breast cancer in high risk women. However, studies have not included enough females with PJS to determine efficacy in this population. Tamoxifen use is associated with a reduction in contralateral breast cancer risk in BRCA1 and BRCA2 pathogenic variant carriers with breast cancer; such benefit is greater if ovaries are still intact.r Similar benefit might be expected in females with PJS. In view of the potential side effects associated with tamoxifen/raloxifene, risk-reducing medications should be discussed with an experienced medical professional to determine the relevant risks and benefits in an individual pathogenic variant carrier. See COSA - Medications to lower the risk of breast cancer: clinician guide.
Cervical adenocarcinoma, in particular minimal deviation adenocarcinoma (adenoma malignum), is the most frequently reported gynaecological cancer in women with PJS.r There is no evidence-based data on routine cervical screening in PJS. Expert consensus recommendations include annual endocervical smears for cytology and pelvic examination by an experienced gynaecological oncologist (preferably) or gynaecologist from age 25 years.rrr Women need specific screening for this form of cervical cancer, as it is not detected by the screening method used by the national cervical screening program (which tests for human papillomavirus). The request form should highlight the diagnosis of PJS to the reporting pathologist so that they are alerted to the possibility of adenoma malignum.
Ovarian cancer (sex cord tumours)
Females are at increased risk of sex cord tumours of the ovary (SCTAT), which may be benign or malignant. These tumours can occur from infancy but are most common in the fourth and fifth decades. Hyperoestrogenism may occur. Recommendations for annual abdominal examination to assess for abdominal mass are based on low level evidence.rr There is no evidence for routine abdominal imaging or CA125 testing.
Individuals with PJS have an increased lifetime risk of pancreatic cancer, however there is no strong evidence that pancreatic cancer screening is beneficial. Pancreatic cancer screening should only be performed as part of a clinical research protocol.r
Males may be at increased risk of large cell calcifying Sertoli cell tumours (LCCSCTs) of the testis. These most commonly present in childhood and may present with feminisation.r Annual clinical assessment should include testicular examination, growth and height velocity, and signs of feminisation including gynaecomastia. There is no evidence to support routine testicular ultrasound. If signs of LCCSCTs are identified, refer to a paediatric endocrinologist.r
There may be an increased risk of lung cancer, especially for males. Advice should be given about the benefits of avoiding cigarette smoking.