Prostate Cancer

Copyright 2006 Radoslaw Pilarski

Etiology

Etiology of prostate cancer development is not completely known. Factors that can influence the creation and development of this type of cancer include:

genetic factors increase in risk of falling ill among men with a positive family history regarding the prostate cancer. Mutations of suppressor genes are also taken into consideration (p53)

dietetic factors food rich in saturated fatty acids probably increases the risk of falling ill whereas the consumption of soya and rice may have a beneficial protective effect racial and geographical factors Afro-Americans are 100% more likely to fall ill, whereas the lowest death rate is reported in Japan and in China

occupational factors cancerogenous influence of heavy metals and toxins infectious factors viral infection may lead to/ be the cause of anaplasia of adenocyte cells of prostate

Histopathologically, 95% prostate cancer cases occur in the form of adenocarcinoma. Other types (primary intracellular cancer, squamous carcinoma, anaplastic carcinoma, and sarcoma) are rarely met. Adenocarcinoma usually develops in the peripheral area of the prostate (85%), in the transition area (25% ) and in the central area (5%).

Symptoms

In symptomatology of the prostate cancer, 4 clinical forms are distinguished:

1) visible form with distinct pathological symptoms 2) latent form (carcinoma latens) with no distinct pathological symptoms found 3) hidden form (ca occultum) which is detected in the case of distinct ailments caused by the existence of remote metastases, however changes in prostate are not found in the course of per rectum examination 4) accidentally detected form – based on histopathological test of the gland that was removed because of prostate overgrowth, or based on biochemical tests (PSA) During the development of prostate cancer, an induction phase that lasts about 30 years which is clinically invisible can be distinguished. During the next stage – in situ phase (5-10 years) and invasive phase (1 year), ailments connected with the local growth of tumour start to appear. During this period, symptoms connected with sub bladder obstacle appear including mainly: – pallakiuria – nycturia – weak urine stream – painful vesical tenesmus – impression of incompletion of bladder emptying The above-mentioned symptoms are typical of cancer and in some cases they may suggest mild overgrowth of prostate, or neurogenic or athermatous bladder disorders. During the dissemination phase (about 5 years), prostate cancer develops continuously infiltrating surrounding organs, such as: urinary bladder, rectum, ureters, pelvic walls and leading to urinary retention in kidneys and to secondary failure of function. Ailments typical for this period include: – haematuria – dysuria – urinary incontinence – erection disorders – aches of perineum, lumbar area and anus – haematospermia Metastases spread through the lymphatic vessels and the vascular system. Symptoms caused by the existence of remote metastases are as follows: – osteodynia and pathological fractures – pressure symptoms and spinal paralysis – lymphadema of limbs – clotting disorders – cachexy – coma

DIAGNOSTICS

In order to diagnose the prostate cancer, patient should undergo per rectum tests (DRE), PSA concentration (prostate specific antigen) in blood serum should be determined, ultrasonography per rectum examination (TRUS – transrectal ultrasound) should be done and if there is a suspicion of prostate cancer, histopathological test of the material obtained through a per rectum thick-needle biopsy done under the ultrasound control should take place. Histopathological test is the only test that confirms the presence of cancerous cells in the prostate gland area. DRE, which is an examination of sensitivity of 80% sensitivity and of specificity of 60%, enables to seize changes in the area of the prostate such as consistency change, palpable nodules and hardenings. It is the base for sending a patient to a diagnostic biopsy. At present, it is believed that cytological diagnosis achieved through a fine-needle biopsy is not sufficient to make a right diagnosis. It results from the fact that the assessment according to Gleasons classification is an important prognostic factor for the prostate cancer (see: prognostic factors). That is why a thick-needle biopsy is performed. Ultrasound use enables to take precise samples from suspicious foci. If there are no changes in TRUS picture, “sextant biopsy” is done (samples got for several places).

Recommendations for the biopsy of prostate gland: 1) palpable suspicion of the prostate cancer 2) PSA value over 15ng/ml regardless of DRE or TRUS tests 3) PSA value between 4 and 15 ng/ml with abnormalities detected during DRE or TRUS tests 4) PSA value exceeds the norm for a given age in the case of a positive family history regarding the prostate cancer

Recommendations for TRUS: 1) PSA between 4 and 12 ng/ml with abnormalities detected 2) questionable result of DRE test 3) necessity of a thick-needle biopsy Other diagnostic tests, such as CT and urography are not routinely performed because their value is questionable as far as the assessment of local stage and invasion of adjacent lymph nodes is concerned. Nowadays, magnetic resonance tomography done using transrectal coli (endorectal coil MRI – ERMR) to observe the prostate arouses great interest. Despite the increased sensitivity of the degree of the local stage, costs of the test do not allow for its routine use in the prostate cancer diagnosis. Scintigraphy of the skeleton is the most sensitive test (97%) in bone metastases detection. It is assumed that a patient with PSA under 10 ng/ml does not undergo scintigraphy because the probability of metastases is low.

Screening:

Screening: It is recommended that patients aged over 50 should undergo per rectum tests and PSA level tests every year.

PROGNOSTIC FACTORS:

Three groups of prognostic factors can be distinguished in the case of the prostate cancer:

1) development stage according to TNM 2) differentiation degree of the cancer based on the classification of Gleason and Mostofi 3) PSA level (prostate-specific antigen) in serum TNM classification

Preoperative assessment of the stage of the prostate cancer is made based on the above-mentioned tests.

T-stage: primary tumour

Tx – primary tumour cannot be assessed T0 – no evidence of primary tumour T1 – clinically unapparent tumour; not palpable or visible by per rectum imaging T1a – incidental tumour found in histopathological tests after transurethral resection of the prostate or after operational adenectomy: found in 5% or less resected tissue T1b – as above; found in more than 5% resected tissue T1c – tumour identified histopathologically by a needle biopsy (because of high PSA) T2 – tumour confined within the prostate gland T2a – tumour involves less than half of one lobe T2b – tumour involves more than half of one lobe only T2c – tumour involves both lobes T3 – tumour extends through the prostatic capsule T3a – extracapsular extensions (unilateral) T3b – extracapsular extensions (bilateral) T3c – tumour invades seminal vesicles T4 – tumour is fixed, invades adjacent structures other than seminal vesicles T4a – tumour invades bladder neck and/or external sphincter and/or rectum T4b – tumour invades levator muscles and/or pelvic wall N-stage: regional lymph nodes

Nx – regional lymph nodes cannot be assessed N0 – no regional lymph node metastases N1 – metastasis to a single regional lymph node with the diameter under 2cm N2 – metastasis to a single regional lymph node with the diameter > 2cm but

Mx – remote metastasis cannot be assessed M0 – no remote metastases M1 – remote metastases M1a – non-regional lymph nodes M1b – bones M1c – other sites According to Whitmor-Catalon classification, grades A, B, C, and D correspond to T1, T2, T3 and T4 of TNM classification respectively.

Degree of cancer differentiation:

Degree of differentiation is defined according to 2 classifications: by Mostofi and by Gleason.

Mostofis classification uses a 3-grade assessment of differentiation dependent on the degree of cell anaplasia grading (G1-G3). The higher grade, the lower differentiation of cancer tissue, the greater atypy and at the same time, malignancy. In the case of a 10-grade Gleason system, the two extreme histological images in the preparation are assessed and then, added to produce a final grade.

PSA is a proteolyctic enzyme responsible for sperm melting. It is mainly produced by glandular epithelium, it might be also produced in organs such as salivary glands, pancreas and mammary gland and by clear cell carcinoma. Commonly used norm is the following: 0-4 ng/ml. Such concentration of PSA is found among 97% of men over 40. The level over 12 ng/ml is always connected with pathology. Difficulties with diagnosis are found among patients who have this level between 5-10 ng/ml because it may both stem from the prostate cancer or a mild overgrowth of the prostate, which causes the necessity of diagnostic methods use, such as TRUS. This test makes it possible to determine PSA density (PSAD – PSA density) – PSA concentration converted to prostate volume unit. It should be under 0.15 ng/ml/g. In the case of prostate cancer differentiation and mild overgrowth of prostate, free to total PSA (PSA F/T) is used. If it is over 20%, one may assume the presence of cancerous cells in the gland. PSA level does not correlate well enough with the natural development of the prostate cancer. However, it is useful as a prognostic factor after the treatment applied and in prognosis determination. However, high final levels indicate low survival rate.

TREATMENT

Proceeding strategy in patients with the prostate cancer depends on the degree of histological malignancy, the degree of local stage of development, coexisting diseases and age of a patient. There are many controversies as far as the choice of treatment is concerned. Radical treatment is possible in T1, T2 and N0 and Mo stages. In advanced cases (T3, T4, N-+, M-+), the procedure is restricted to delay the cancer progression and mitigate its effects (palliative treatment).

Surgery treatment – radical prostatectomy

The surgery consists in the prostate gland removal together with spermatic vesicles and adjacent tissues. Surgery is done through retropubic, transcoccgeal, perineal approach or through laparoscopy. Lymphadenectomy constitutes an integral part of the surgery. If the approach makes it impossible to remove the gland and lymph nodes (perineal approach) at the same time, a separate surgery is carried out. It precedes the operation proper. It is believed that cancerous cells found in the removed lymph nodes are the reason why prostatectomy cannot be performed. Invasion of lymph nodes to a certain extent suggests PSA level over 40ng/ml together with grade >7 in Gleasons scale.

Recommendations for surgery:

1) cancer limited to the prostate gland (T1BN0M0Gx – T2N0M0Gx, T1AN0M0G3) 2) predictable life span over 10 years 3) consent of a patient If positive chirurgical margins, capsule infiltration or cancerous changes in the removed lymph nodes are found in postoperative microscopic assessment, the prognosis is worse such patients are qualified for palliative treatment. The death rate in the postoperative period does not exceed 5%. Intraoperative complications first of all include: bleeding from Santorinis plexus, damage of rectum wall, underpinning of ureter. Early complications after surgery: thrombotic and embolic complications (phlebothrombosis 3-12%, lung embolism 2-5%) and lymphocele. Late postoperative complications after prostatectomy include: urinary incontinence, erection disorders and narrowing of urethro-vesicular junction).

Radiotherapy

Apart from radical prostatectomy, radiotherapy is an effective method of treatment for patients with regional advanced prostate cancer. In radical treatment, the most frequently done using radiation from external sources, the dose of 50-70 Gy in fractions continuing over 5-7 weeks are given. T1ABC – T2ABCG1 and T1ABCG2 stages require radiation limited to the prostate. In other cases, area that is radiated includes adjacent lymph nodes as well. In recent years, multidimensional imaging with CT (3D conformal radiotherapy) is used in the treatment planning.

Brachytherapy constitutes another method that is used.

Recommendations for radical radiotherapy of the prostate:

1) prostate cancer confined with the organ 2) sufficiently long predictable survival span 3) no disorders in lower urinary tract 4) no disorders in rectum and colon 5) consent of patient to carry out treatment 6) early complications of radiation energy treatment (30% of patients) include dysuria, haematuria, diarrhoea, rectal tenesmus, inflammation of large intestine and rectum. Among later complications (11% of patients) chronic diarrhea, ulceration of rectum, bladder neck stenosis and intestinal fistula stenosis are observed.

Control of patients after radical prostatectomy and radical radiotherapy:

– per rectum test, PSA level in blood serum each 3 months. PSA level should be lower than 1 ng/ml (after radical prostatectomy it should be near to 0). Increase over 0.5 ng/ml within a year means failure of radiotherapy. Hormonotherapy

Hormonal therapy is mainly used as palliative treatment in advanced prostate cancer. It makes it possible to stop symptoms of the disease for some time and then, further progression of the disease takes place. Nowadays, the use of therapy in pulsation system is considered as it delays the development of hormone-resistant cell clones.

Ways of hormonal treatment include: 1) surgery castration (orchidectomy) 2) anti-androgens a) non-steroid b) steroid 3) analogues LH-RH 4) oestrogens, progestogens, inhibitors of androgens synthetase Hormonotherapy by analogues LH-RH is also recommended before planned radical radiotherapy. In the case of hormone-resistant cancer, treatment with combined cytoctatic and hormone (estramustine), however without significant effects.

PROGNOSIS

Prognosis depends on the development stage, degree of differentiation and PSA level (see: prognostic factors).

In T1A, B stage prognosis is good. 10-years survival 35-80%, death rate of the cancer 7-30%. In T2 stage, overall survival equals 34-85%, death rate equals 8-26%. In T3 stage, among patients who undergo non-invasive treatment for 9 years, overall death rate equalled 63%, from cancer 30%. Depending on the degree of cancer differentiation, 10-year survival of patients is the following: for cells well differentiated – 81%, for cells moderately differentiated – 58% and for cells poorly differentiated – 26%.

Assuming Blood Is From Hemorrhoids And It Is Actually From Colon Cancer Might Make Physician Liable For Medical Malpractice

Being told one has colon cancer tends to bring up dread in nearly all of people. It can therefore feel quite reassuring for your doctor say that you just have hemorrhoids and there is no need to be concerned about the blood in your stool. But this reassurance should only come after the doctor has eliminated the likelihood of colon cancer (and other possibly dangerous gastrointestinal issues). Otherwise, you might not learn that you have colon cancer until it is too late. Should a doctor conclude without testing assumes that reports of blood in the stool or rectal bleeding by a patient are from hemorrhoids and it subsequently is discovered that the patient had colon cancer all along, that doctor might not have met the standard of care. Under those circimstances, the patient might have a legal claim against that physician.

It is generally thought that there are presently over 10 million men and women with hemorrhoids. An additional 1,000,000 new cases of hemorrhoids will likely arise this year as opposed to a little more than the 100 thousand new cases of colon cancer that will be identified . Further, not all colon cancers bleed. When they do, the bleeding may be intermittent. Also subject to where the cancer is in the colon, the blood might not actually be seen in the stool. Possibly it is in part as a result of the difference in the volume of instances being identified that a number of physicians simply consider that the existence of blood in the stool or rectal bleeding is due to hemorrhoids. This amounts to gambling, pure and simple. A physician who reaches this conclusion will be right greater than 90% of the time. It seems sensible, doesnt it? The problem, though, is that if the physician is wrong in this diagnosis, the patient might not learn he or she has colon cancer until it has developed to an advanced stage, maybe even to where treatment is no longer effective.

When colon cancer is found while still contained within the colon, the patients 5 year survival rate will normally be above eighty percent. The five year survival rate is a statistical indicator of the percentage of patients who survive the disease for a minimum of five years subsequent to diagnosis. Treatment for early stage colon cancer normally entails only surgery in order to take out the tumor and surrounding portions of the colon. Based on variables like how advanced the cancer is and the individual’s medical history (including family medical history), age, and the person’s physical condition, chemotherapy may or may not be required.

For this reason doctors generally recommend that a colonoscopy ought to be ordered right away if a patient has blood in the stool or rectal bleeding. A colonoscopy is a method that uses a flexible tube with a camera on the end is used to see the interior of the colon. If growths (polyps or tumors) are detected, they can be removed (if small enough) or sampled and tested for the existence of cancer (by biopsy). Providing no cancer is found from the colonoscopy can colon cancer be ruled out as a cause of the blood.

However, if the cancer is diagnosed after it has spread past the colon and has reached the lymph nodes, the person’s five year survival rate will generally be around 53%. Aside from surgery to take out the tumor and adjacent portions of the colon treatment for this stage of colon cancer requires chemotherapy in an attempt to eliminate any cancer that might remain in the body. By the time the cancer spreads to other organs such as the liver, lungs, or brain, the patients five year survival rate is lowered to roughly 8%. If treatment options exist for a patient at this point, they might include surgery, chemotherapy, radiation therapy, and other medications. Treatment might no longer be helpful once the cancer is this advanced. When treatment ceases to be helpful, colon cancer is fatal. This year, roughly 48,000 individuals will die in the U.S. from colon cancer metastasis.

As a result of telling the patient that blood in the stool or rectal bleeding as resulting from hemorrhoids without conducting the correct tests to eliminate the possibility of colon cancer, a doctor places the patient at risk of not learning he or she has colon cancer until it progresses to an advanced, possibly no longer treatable, stage. This may amount to a departure from the accepted standard of medical care and might result in a medical malpractice case.

If you or a a member of your family were assured by a physician that blood in the stool or rectal bleeding were because of only hemorrhoids, and were later diagnosed with advanced colon cancer, you ought to contact an attorney at once. This article is for informational usage only and does not constitute legal (or medical) advice. If you have any medical issues you should seek advice from doctor. You should not act, or refrain from acting, based upon any information in this article but ought to instead consult with an attorney. A competent attorney who is experienced in medical malpractice may be able to help you determine if you have a claim for a delay in the diagnosis of the colon cancer. Immediately contact an attorney are there is a time limit in lawsuits such as these.

Buying A Movado Watch Can Help With Breast Cancer Awareness

When you’re a little kid, the month of October is an incredible thing, because it means that Halloween is right around the corner. Every child in America is well aware that October ends with a gigantic costume party that involves fun, adventure, and most important of all, a plethora of free candy.

However, as many adults are aware, October is also Breast Cancer Awareness Month, and because of that many companies and organizations are releasing “pink” memorabilia as a way to warn individuals of the dangers of breast cancer.

Amongst those products is the 2010 Coach “Think Pink” Breast Cancer Awareness Movado watch. A collaboration between designer companies Coach and Movado watch, this timepiece is being sold with the guarantee that 20% of all proceeds are being donated directly to the Breast Cancer Research Foundation. The timepiece is available between October and the end of 2010 at Coach and Movado Watch shops, as well as a number of department stores. With a mother-of-pearl dial, the 2010 Coach “Think Pink” Breast Cancer Awareness Movado watch is well worth the retail price of $248, even if the proceeds weren’t going to support an honorable cause. However, the collaboration between Coach and Movado watch isn’t the only major partnership going on in support of breast cancer research during the month of October. One of the biggest corporations in America is also getting in on the Breast Cancer Awareness: The National Football League

As many fans have undoubtedly noticed, a high majority of NFL players have been wearing pink armbands, gloves, shoes, and towels as a means for showing support for “A Crucial Catch,” a campaign partnership between the NFL and the American Cancer Society. To quote the official NFL website:

“The NFL, its clubs and players are proud to support the fight against breast cancer. Our campaign, “A Crucial Catch”, in partnership with the American Cancer Society, is focused on the importance of annual screenings, especially for women who are over the age of 40. Throughout October, NFL games will feature players, coaches and referees wearing pink game apparel to raise awareness for the campaign, as well as on-field pink ribbon stencils and special K-balls and pink coins. All apparel worn at games by players and coaches and special K-balls and pink coins will auctioned off at NFL Auction (www.NFLAuction.NFL.com), with proceeds benefitting the American Cancer Society and team charities. This is an issue that has directly touched the lives of so many in the NFL family, and we are committed to helping make a difference in breast-cancer prevention.”

There are countless groups and organizations getting in on the action this October. The amount of support truly is unbelievable and seeing “pink” in so many places, from the NFL to a Movado watch, gives even the most pessimistic of individuals the belief that finding a cure is a matter of “when,” not “if.”

Imrt In Breast Cancer

Worldwide breast cancer is the most common malignancy in women. In the developed world, it is responsible for 18 percent of all cases of cancers seen in women. One million new cases of breast cancer are registered worldwide every year and it is the single commonest cause of death among women in the 40- 50 years age group. In India breast cancer is the second commonest cancer seen in the women after carcinoma cervix. Its prevalence is higher in urban women and it accounts for 20% of all cancer related diseases. In Mumbai and Delhi, it is the commonest malignancy seen in women. In India it has an incidence of 17-40 cases per 1, 00,000 population and the 5 years survival is 42.3 percent to 46.8 percent.

Conventionally radiotherapy in early breast cancers is done by the whole breast technique which utilizes two tangential ports. Upper margin of the radiotherapy field lies at the first intercostals space, and the lower margin lies 2 cm below the inferior mammary line. Medial margin is in the midsternal line and the lateral margin is at the mid axillary line. A total dose of 50 Gy in 25 fractions is given over 5 weeks by conventional fractionation followed by boost of 10-20 Gy. This technique is easy to setup, and avoids the junction dose. Computerizes planning is done for dose optimization. Standard 2d treatment (conventional radiotherapy) techniques utilizes a simplistic view of patient anatomy and it creates hot spot because lung transmission is not accurately included and thinner regions of breast (superior and inferior) are modeled like the thickest slice of the breast. Thus conventional radiotherapy has limitations in the treatment of breast cancer and these include.

Dose inhomogeniety due to change in the contours of the breast 1520 percent of dose inhomogenicity in the superior and the inferior planes of the breast occurs. The medial and lateral aspects of the breast get higher doses of radiation.

Radiation accompaniments i. e. radiation effects on normal tissues in the field are seen uncommonly but they do occur in the lungs and the heart. Newer techniques are able to minimize them.

The newer techniques are used to

Improve dose homogeneity within the tumor volume.
Avoid radiation to normal tissues in the area.
Reduce side effects related to the radiation treatment.
Improve local tumor control and overall survival of the patient.
In an attempt to address the above mentioned parameters a number of newer radiotherapy techniques have been introduced for the treatment of early breast cancer. These include IMRT, external beam RT using 3D conformal RT, Intraoperative Electron Beam RT, Mammosite Ballon Branchytherapy and interstitial branchytherapy. Gated radiotherapy is also available.

All these techniques need a CT scan based treatment planning system and require the use of tissue compensators.

IMRT

IMRT is an approach to conformal therapy that not only delivers high dose to the tumor tissue but also ensures low dose to the surrounding normal tissue. The dose is varied depending on the tumor volume. A higher dose of radiation can be delivered to the areas with high tumor volume, a small dose where tumor volume is not so high and a minimal dose is delivered to surrounding normal tissue. By these means a higher tumor control probability and minimal or no side effects of radiotherapy are achieved, resulting in improved therapeutic ratio and better patient care.

Important normal structures that need to be examined and protected while IMRT for breast cancer is being planned include

Heart
Ipsilateral lung
Contralateral lung
Contralateral breast
Tissues outside the breast planned tumor volume (PTV)
Dose specifications in IMRT are as follows:

Breast volume receiving 105% of prescribed dose should be
Breast volume receiving 110% of prescribed dose should be 55
Breast receiving 115% of prescribed dose should be

Common Signs Of The Beginning Stages Of Colon Cancer

Do you think you are healthy? If so how healthy are you actually? When was the last time you underwent a colonoscopy? If the answer to that question is never, then there is no better time than now to schedule one. If you dont believe me, listen to this startling fact: In the United States, 1 in 17 people will develop colorectal cancer.

You may have no symptoms in the early stages of the collateral cancer. Often times, many people dont. That doesnt mean they arent there. When they finally do appear, they’ll vary, depending on the tumors size and location in your large intestine.

Every health professional will agree that is best to get regular screenings rather than rely on symptoms to alert you to the presence of cancer. This is because colorectal cancer can go undetected for years before you notice any symptoms. That doesnt mean you shouldnt know what to look for. After all, knowing some of the symptoms can’t hurt. If you experience any of the following symptoms for more than about a week, please talk to your doctor or physician about getting screened for colorectal cancer.

Stool is thinner than normal – Everything in your system is flowing fine until a tumor starts to grow, causing an obstruction in the large intestine. As the tumor gets bigger so does the obstruction causing the space around to become smaller. So, as you might expect, tumors toward the end of the colon tend to cause the effect of narrowed stool.

Stomach cramping or bloating – Bloating is usually the result of some sort of bowel obstruction. Cramping is normally caused by constipation or diarrhea. In the more advanced stages of colorectal cancer, severe abdominal cramping is caused by the tumor perforating the bowel wall.

You go to the bathroom more or less often – The presence of a tumor in your bowel makes your whole system go out of whack. As your body adjusts to its presence, demands, and byproducts, you may experience changes in your bowel habits. For example, if a tumor is slowly growing in your colon, it inhibits the flow of solid waste. Youre going to notice that you’re defecating less often. The tumor can obstruct your bowel. You will undoubtedly notice a difference. You are going to get constipated. That’s why it is a good idea to get regular screenings with your doctor rather than relying on symptoms to alert you of the presence of the cancer.

Red blood in or on your stool Most tumors are likely to bleed. They dont bleed a lot or all the time, but they do bleed. As a result of this, this is what causes the blood found in your stool. If the tumor is formed in the right of the colon, the blood will most likely be dried and virtually invisible by the time it leaves the body. However, if the tumor is in the rectum or toward the end of the left colon, it will be fresh and therefore, bright red.

Regularly feel tired If you feel tired all the time no matter what time of the day it may be, there something else going on with your body. One possibility is a condition called anemia. This occurs when your red blood cells aren’t fully operational for some reason. Your red blood cells are not carrying enough oxygen to your body like they’re supposed be. As a result of this, your body is left feeling tired. Anemia can be caused by tumors.

Unexplained weight loss – Many of us would love to experience some kind of weight loss. But, losing weight without trying is really something to question. weight loss that comes out of nowhere is a sign that something is wrong in your body. With colorectal cancer, unexplained weight loss is a prime indicator that a tumor is blocking the bowel somewhere.