Retinitis pigmentosa is a group of inherited eye diseases that cause cells in the retina to gradually break down, leading to progressive vision loss that typically begins in childhood with difficulty seeing at night and eventually narrows the field of vision.

Retinoblastoma is a rare eye cancer that develops in the retina, the light-sensing layer at the back of the eye. Though uncommon, it is the most common eye cancer in childhood, typically affecting children under age 5. With early detection and modern treatment, survival rates are very high, often exceeding 95% in specialized care centers.

Rett syndrome is a rare genetic disorder that disrupts brain development, causing severe physical and mental disabilities primarily in girls. After months of normal growth, children lose abilities they once had—from speaking and walking to using their hands purposefully—creating a profound impact on nearly every aspect of their lives.

Rhabdoid tumour is a rare and highly aggressive cancer that primarily affects babies and very young children, developing rapidly in the kidneys, brain, soft tissues, or other organs throughout the body.

Rhabdomyosarcoma is a rare type of cancer that develops in muscle tissue and primarily affects children and teenagers, though adults can also be diagnosed. This aggressive disease requires a combination of treatments and can occur anywhere in the body, making early recognition of symptoms crucial for better outcomes.

When rhabdomyosarcoma returns after treatment, it presents one of the most challenging situations in childhood cancer care, with nearly one-third of patients with localized disease and over two-thirds with metastatic disease experiencing recurrence, typically within three years of initial diagnosis.

Richter’s syndrome is a rare but serious complication where chronic lymphocytic leukemia transforms rapidly into a more aggressive form of cancer, usually an aggressive type of lymphoma, requiring immediate medical attention and specialized treatment.

Rosai-Dorfman syndrome is a rare condition where the body produces too many white blood cells called histiocytes, which can accumulate in lymph nodes and other parts of the body, causing swelling and various symptoms depending on where these cells collect.