Colon Cancer, Lynch Syndrome and the Case for Cascade Testing

Ultrasound should be done once every 6 months for a chronic liver disease patient, along with alpha-fetoprotein testing every 6 months. The skill of the radiographer matters because ultrasound is a subjective, operator-dependent test. If there is any doubt on ultrasound, a triple-phase CT scan or a multiphasic MRI should be done immediately.

The key is always the right diagnosis at the right time. Liver cancer carries a real risk of coagulopathy and bleeding, so any patient with chronic liver disease should have regular PT, PTT and INR testing. If there is any bleeding diathesis, it needs to be treated, including with vitamin K and blood products if needed. Chronic liver disease patients also commonly have low white cell counts and low platelets, so basic blood counts should be checked regularly alongside liver and kidney function tests.

Leukemias are broadly acute or chronic. Acute leukemias have a short history with low hemoglobin, white cell count and platelets, presenting with fever and bleeding. Chronic leukemias, chronic myeloid leukemia (CML) or chronic lymphocytic leukemia (CLL), generally occur in older age groups and are often managed with tablets alone. Acute leukemias are either AML or ALL. Genetic testing subcategorises each: CML needs confirmation of Philadelphia chromosome or BCR-ABL positivity; CLL needs a FISH panel to check p53 status and risk category; AML is categorised as good, intermediate or high risk. ALL is the most common leukemia in children and young adults and is treated with steroids followed by chemotherapy based on T-cell or B-cell type. AML M3, acute promyelocytic leukemia, is rare but very curable with ATRA or arsenic trioxide tablets; non-M3 AML needs chemotherapy.

Please write in with any questions, over WhatsApp or text, at any time. Many patients cannot travel to India, so the goal is to help diagnose and treat them on time wherever they are. Prepare a doctor's note with the relevant clinical details and share it; if the picture is clear, specific pointers on managing the case can be given from that.

Self-examination should be done by the woman herself, using the opposite hand on the opposite breast with three fingers held flat, including the axilla and neck. Clinical breast examination should be done by anyone properly trained, which can include nurse practitioners, physician assistants, internal medicine doctors, general surgeons, gynaecologists and oncologists. Training, not job title, is what matters, since missing lesions is common when the examiner has not been trained. GPs and internal medicine doctors should learn the technique and offer it to every woman who comes to the clinic.

Anaemia is common enough in menstruating women that it can be explained by normal physiology, but there is no such explanation in a young man. A haemoglobin of 9 g/dL in a 37 year old male warrants investigation rather than being attributed to diet or fatigue.

An MSI-high, or microsatellite instability-high, result on immunohistochemistry points toward a familial cancer syndrome rather than a sporadic tumour. Combined with a family pattern of related cancers on one side of the family, it is one of the criteria used to test for Lynch syndrome.

Cascade testing is the practice of testing siblings, parents, and children of a confirmed Lynch syndrome patient, since they may carry the same predisposition. In one case, a brother who tested positive underwent a screening colonoscopy and required no treatment at all, because the risk was identified before any tumour had formed.

An annual faecal occult blood test is recommended from age 45. Where screening colonoscopy is standard practice, it is recommended once every 10 years starting at 45, or a sigmoidoscopy once every 5 years as an alternative.

When the disease is very localised at the time of surgery, no further treatment is needed. Patients with a strong family history and MSI-high tumours tend to do extremely well after surgery alone, though immunotherapy rather than standard chemotherapy would be the recommended next step if the disease were advanced given the MSI-high status.