What are the signs and early symptoms of anal cancer?
Executive summary
Anal cancer often begins with subtle, easily missed signs — most commonly minor rectal bleeding — and early symptoms frequently mimic benign conditions such as hemorrhoids or fissures, which can delay diagnosis [1] [2] [3]. A clear pattern to watch for includes persistent or recurrent bleeding, new lumps or masses at the anal opening, ongoing pain or itching, and changes in bowel habits; any of these that do not resolve warrant medical evaluation because early detection improves outcomes [1] [4] [5].
1. Bleeding: the common but deceptively mild first signal
Minor bright-red bleeding from the anus or blood on toilet paper is the single most frequently reported early sign of anal cancer, and it is often the first symptom people notice — yet that same mild bleeding is far more commonly caused by hemorrhoids or fissures, which is why experts urge evaluation rather than assumption [1] [2] [6].
2. Lumps or masses: a palpable clue sometimes mistaken for hemorrhoids
A new lump, protrusion, or mass at or near the anal opening can be felt or seen and may represent a tumor; patients and clinicians can confuse such findings with enlarged hemorrhoids, underscoring the need for a focused exam and appropriate diagnostic testing when a lump persists [1] [7] [8].
3. Pain, pressure and persistent itching: vague symptoms that matter when they don't go away
Chronic anal pain, a feeling of fullness, pressure, or severe itching (pruritus) around or inside the anus are commonly listed early symptoms and should raise concern when they are persistent or worsening rather than transient or clearly linked to an alternate cause [9] [4] [5].
4. Bowel changes and discharge: clues from stool and sensation
Changes such as narrower or thinner stools, new constipation or diarrhea, mucus discharge, or a sense that the bowel hasn’t fully emptied can accompany early anal tumors and may point to a lesion narrowing the anal canal — symptoms that demand evaluation because they can also reflect several noncancerous conditions [10] [5] [4].
5. When symptoms signal more than local disease: lymph nodes and systemic signs
If cancer spreads, swollen groin lymph nodes may become palpable and patients might experience more pronounced pain or fatigue; clinicians use these findings along with imaging and biopsy to stage disease, but early-stage cancers are often localized and detected because of the symptoms already described [4] [3].
6. The diagnostic challenge and why vigilance matters
Because early anal‑cancer symptoms overlap heavily with very common benign problems like hemorrhoids, anal warts, and fissures, many people — and even practitioners — initially attribute bleeding, itching, or pain to noncancer causes; authoritative centers therefore recommend that persistent, recurrent, or unexplained symptoms be investigated with clinical exam and, when indicated, biopsies or imaging to avoid delayed diagnosis [7] [6] [3].
7. Prevention and context: HPV link and screening nuance
A large proportion of anal squamous cell cancers are associated with high‑risk human papillomavirus (HPV) infection, and HPV vaccination reduces the risk of anal cancer — yet routine population screening for anal cancer is not currently recommended, so prevention and prompt evaluation of symptoms remain central to early detection strategies [6] [10] [11].
Anal cancer can be subtle at first; the consistent red flags across major cancer centers and patient information sources are persistent rectal bleeding, a new lump, ongoing pain or itching, and changes in bowel habits or discharge — any of which that do not resolve or that recur should prompt a medical assessment rather than dismissal as hemorrhoids [1] [4] [8]. Sources cited include the American Cancer Society, Cancer Research UK, MD Anderson, Memorial Sloan Kettering, and leading U.S. cancer centers that outline the symptom profile and the diagnostic caution required [1] [4] [7] [12] [11].