COMPLICATIONS OF PELVIC RADIOTHERAPY-2.pptx

DETAILS WITH ACUTE AND CHRONIC TOXICITIES OF PELVIC CASES, proctitis, enteritis, cystitis, and its management, haematological toxicities, related to pelvic rt and its subsequent ,management.

1. COMPLICATIONS OF PELVIC RADIOTHERAPY PRESENTERS: DR TARINI G, DR ANUSHA KOTA MODERATOR: DR MOHAN KUMAR

2. PELVIC RT INDICATIONS • Ca Cervix • Ca Endometrium • Ca Vulva and Vagina • Ca Bladder • Ca Rectum • Ca Anal Canal • Ca Penis • Carcinoma Prostate

3. ORGANS AT RISK DURING PELVIC RT • Bladder • Rectum • Urethra, ureter • Small bowel • Vagina • Gonads • Bone Marrow • Bones – Femoral Heads, Pelvic and Sacral Bones, Vertebrae

4. Acute Toxicities Acute toxicities occur during treatment and up to 90 days post-RT . Peak severity is usually last 1–2 weeks of RT and immediately after completion. Most symptoms are self-limiting and resolve with supportive care. Persistent or severe symptoms should prompt investigation for infection or other complications . Patient education is crucial: hydration, diet modifications, hygiene, and early reporting of symptoms.

5. System / Organ Chronic Toxicities Typical Timeline Bowel (Small & Large Intestine) Chronic radiation enteritis/proctitis, strictures, bowel obstruction, fistulas, perforation, chronic diarrhea, malabsorption 6 months – 5 years Bladder / Urinary Tract Radiation cystitis, hematuria, bladder fibrosis, decreased capacity, urinary incontinence, vesicovaginal fistula, ureteric strictures 1 – 3 years Reproductive Organs Vaginal stenosis, shortening, dryness, dyspareunia, ovarian failure (premature menopause), infertility 6 months – years Bone Pelvic insufficiency fractures, osteoradionecrosis of pelvic bones, avascular necrosis of femoral head 1 – 3 years Skin & Soft Tissue Fibrosis, poor wound healing, chronic ulceration, telangiectasia, secondary malignancies (rare) >2 years Lymphatics Chronic lymphedema (lower limbs) Months – years

6. GASTROINTESTINAL TOXICITIES

7. PATHO- PHYSIOLOGY Initial injury: Radiation causes DNA damage to rapidly dividing intestinal epithelial cells. Inflammation: Leads to mucosal breakdown, ulceration, and loss of barrier function. Vascular injury: Progressive endarteritis and ischemia → hypoxia and chronic damage. Fibrosis: Fibroblast activation → stricture, adhesions, fistula formation.

8. RADIATION ENTERITIS Radiation enteritis is inflammation and injury of the small and/or large bowel caused by ionizing radiation , usually given for pelvic or abdominal malignancies. Radiation damages rapidly dividing mucosal cells , leading to loss of mucosal integrity, inflammation, fibrosis, and vascular damage . Time frame: Acute radiation enteritis: During RT and up to 90 days post-treatment Chronic radiation enteritis: >90 days to years after RT

9. ACUTE ENTERITIS S ymptoms: Altered bowel habits 94% • Loose stool 80% (required antidiarrheal medication 40%) • Frequency 74% • Bloating 65% • Pain 60% • Distress 48% • Tenesmus 44% • Restrictions in daily activity >40% • Urgency 39% Khalid U, McGough C, Hackett C, Blake P, Harrington KJ, Khoo VS et al (2006) A modified inflammatory bowel disease questionnaire and the Vaizey Incontinence questionnaire are more sensitive measures of acute gastrointestinal toxicity during pelvic radiotherapy than RTOG grading. Int J Radiat Oncol Biol Phys 64(5):1432–1441

10. RISK FACTORS: Category Risk Factors Radiotherapy-related High total dose (>45–50 Gy), large fraction size, planning/technique, concurrent chemotherapy Patient-related Diabetes, hypertension, smoking, poor nutritional status, prior abdominal surgeries Anatomical Short small bowel loops, fixed bowel segments within the pelvis

11. RTOG/EORTC lower GI toxicity grading (Acute)

12. MANAGEMENT Approach Interventions Dietary Low-residue diet, avoid lactose/caffeine/spicy foods, adequate hydration Medications - Antidiarrheals: Loperamide, diphenoxylate-atropine - Probiotics (to restore gut flora) - Antispasmodics for cramping Skin care For perianal irritation – lignocaine gel Hydration & electrolytes Oral or IV fluids if severe diarrhea

13. CHRONIC ENTERITIS RTOG Small/Large Bowel Toxicity

14. A randomized study evaluated the toxicity and clinical outcomes of 44 patients with locally advanced cervical cancer who received either whole-pelvis RT or IMRT at a dose of 50 .4 Gy in 28 fractions administered with concurrent cisplatin 40 mg/m followed by HDR intracavitary RT. Compared with 3D-CRT, IMRT was associated with significantly fewer grade 2 acute GI toxicities (63.6% vs 31.8%;) and grad3 acute GI toxicities(27.3% vs 4.5%;). In addition, IMRT was associated with Less chronic G I toxicity (50% vs 13.6%). Dosimetric comparison between the 2 group demonstrated significantly less dose to the rectum and small bowel, which likely accounted for these important clinical differences.

15. Clinical Problem Management Strategy Medications / Interventions Notes 1) Chronic diarrhea & malabsorption Control symptoms, improve absorption - Antidiarrheals: Loperamide - Cholestyramine (for bile salt diarrhea) - Probiotics (supportive) - Vitamin and mineral supplementation: B12, iron, folate Assess for bacterial overgrowth, lactose intolerance 2) Nutritional deficiencies & weight loss Optimize nutrition, prevent malnutrition - High-calorie, high-protein diet - Oral nutritional supplements - Parenteral nutrition (TPN) if severe malabsorption or obstruction Regular weight and albumin monitoring 3) Chronic rectal bleeding (telangiectasia) Stop bleeding, improve mucosal health - Topical sucralfate enemas Avoid aggressive cauterization to prevent ulceration MANAGEMENT

16. RADIATION PROCTITIS

17. RTOG GRADING

18. ACUTE RADIATION PROCTITIS Definition Radiation proctitis is inflammation and injury to the rectal mucosa caused by ionizing radiation delivered during pelvic radiotherapy. Acute Radiation Proctitis (ARP): Occurs during RT and within 90 days after completion . Results from direct mucosal injury and inflammation of the rectal lining. It is typically self-limiting and reversible with supportive management. Acute proctitis is a common toxicity in pelvic RT due to the rectum being in the high-dose region , especially in gynecologic malignancies like cervical and endometrial cancers.

19. RISK-FACTORS Category Risk Factors Radiotherapy -related - High total radiation dose (>45–50 Gy) - Use of 2D or 3D conformal RT vs. IMRT - Excessive rectal dose - Brachytherapy boost with improper applicator positioning Patient-related - Diabetes, hypertension, vascular disease - Malnutrition or low BMI - Smoking -Older age (reduced healing capacity) Concurrent therapies - Concurrent chemotherapy (radiosensitizers like cisplatin) - Previous pelvic irradiation Anatomical factors - Prior pelvic surgery or adhesions

20. SYMPTOMS Diarrhea Loose, frequent stools due to impaired absorption from inflamed rectal mucosa Tenesmus Persistent, painful urge to pass stool even when rectum is empty Rectal discomfort Burning, cramping, pelvic fullness, discomfort during defecation Mucus discharge Clear or yellow discharge due to mucosal irritation Mild rectal bleeding Streaks of blood on stool or toilet paper from friable mucosa and early telangiectasia Urgency Sudden need to defecate, sometimes leading to incontinence Systemic symptoms Fatigue, dehydration (if diarrhea is severe), weight loss in extreme cases

21. MANAGEMENT GENERAL MEASURES Details Patient education Explain that symptoms are common and usually self-limiting; importance of reporting worsening symptoms Dietary modification - Low-residue, low-fiber diet - Avoid caffeine, alcohol, spicy foods, and dairy if lactose intolerant - Small, frequent meals Hydration Encourage oral fluids ; electrolyte-rich solutions for severe diarrhea

22. Diarrhea - Loperamide (first-line) - Diphenoxylate-atropine for persistent symptoms Pain & Tenesmus - Topical hydrocortisone suppositories or foam - Topical sucralfate enemas to coat mucosa and reduce inflammation Mucosal healing Aminosalicylate (5-ASA) suppositories in selected cases Perianal irritation Barrier creams like zinc oxide to protect skin. Infection exclusion If symptoms are severe or worsening, rule out infectious colitis (e.g., Clostridium difficile ) and treat appropriately

23. CHRONIC RADIATION PROCTITIS Definition Chronic Radiation Proctitis is a delayed inflammatory and fibrotic injury of the rectal mucosa occurring >90 days after completion of pelvic radiotherapy (RT) . Unlike acute proctitis , it involves irreversible progressive changes such as vascular injury, ischemia, fibrosis, and ulceration. Can manifest months to years post-treatment (commonly 6–24 months after RT).

24. Rectal bleeding (most common) Bright red blood per rectum due to fragile telangiectasia and ulcerations Mucous discharge Chronic inflammation leading to mucosal irritation Tenesmus Persistent urge to defecate, even when rectum is empty Diarrhea Malabsorption from chronic mucosal damage Pelvic pain Deep-seated pain due to fibrosis or ulceration Secondary complications Iron-deficiency anemia, weight loss, fatigue SYMPTOMS

25. MANAGEMENT Indication Treatment Rectal bleeding Topical sucralfate enemas – coat mucosa and promote healing Aminosalicylate suppositories (5-ASA) Severe diarrhea Loperamide or diphenoxylate-atropine Bacterial overgrowth Broad-spectrum antibiotics (metronidazole)

26. Treatment Modality Indication Procedure / Details Notes / Outcomes Topical Corticosteroids (Steroid Retention Enema) Mild-to-moderate inflammation, bleeding, urgency (Grade 1–2) - Hydrocortisone enema or foam retained for 30–60 mins daily or twice daily. - Typically 100 mg hydrocortisone in 60 mL saline Reduces mucosal inflammation and bleeding; useful early step before invasive measures Topical Sucralfate Enema Persistent mucosal ulceration and minor bleeding - 2 g sucralfate in 20–40 mL water, retained for 15–30 mins daily Coats mucosa and promotes healing, can be used along with steroids Telangiectasia Treatment Recurrent painless rectal bleeding due to fragile mucosal vessels (Grade 2–3) Endoscopic therapies: • Argon Plasma Coagulation (APC) – preferred • Laser coagulation • Bipolar coagulation APC provides safe, controlled cauterization of telangiectasias, effective in 70–90% cases Argon Plasma Coagulation (APC) First-line endoscopic treatment for persistent bleeding not controlled by medical therapy - Non-contact electrocautery using ionized argon gas - Sessions repeated every 2–3 weeks as needed Risk: ulceration or stricture if over-applied; very effective for telangiectasia

27. Hyperbaric Oxygen Therapy (HBOT) Non-healing ulcers, refractory bleeding, severe mucosal ischemia (Grade 3) - 100% oxygen at 2–2.5 atmospheres for 60–90 mins per session - Typically 20–40 sessions Promotes neovascularization, improves tissue oxygenation, reduces bleeding and pain Formalin Application (Chemical Cauterization) Focal bleeding refractory to APC or where APC unavailable - 4–10% formalin applied topically via soaked gauze or rectal instillation under anesthesia Effective but painful; requires anesthesia and careful monitoring Diversion Colostomy Severe, refractory symptoms or complications (Grade 4) such as perforation, fistula, uncontrolled bleeding - Fecal stream diversion to allow rectal mucosa to heal - May be temporary or permanent Considered last resort; improves quality of life in severe cases Surgical Resection Uncontrollable bleeding, recurrent strictures, or fistulas not responding to other treatments - Proctectomy with or without colostomy High morbidity; reserved for extreme cases

28. BLADDER - CYSTITIS Mechanism of Radiation Damage Urothelium damage Nuclear irregularity Cellular oedema Increased cytoplasmic elements Disruption of tight junctions & polysaccharide laye

29. Acute Radiation Cystitis Chronic Radiation Cystitis Onset During or within weeks of RT Months to years post-RT Pathophysiology Inflammatory response of urothelium; transient Endothelial damage → fibrosis, telangiectasia, bladder ischemia Main Symptoms Dysuria, frequency, urgency, mild hematuria Severe hematuria, pain, fibrosis, incontinence, reduced bladder capacity

30. Symptoms of Radiation-Induced Cystitis Acute side effects : urinary frequency, urgency, dysuria. Late effects : hematuria, fistula, obstruction, ulceration, contracted bladder, vesicovaginal fistula, necrosis, spasm, reduced flow, incontinence. Median onset of late complications : 13–20 months after radiation

31. Grading: Radiation Therapy Oncology Group (RTOG) – Radiation Cystitis Acute Genitourinary Toxicity Grade I – Increased frequency of urine Grade II – Frequency >1 hr/pain requiring local analgesics Grade III – Frequency <1 hr/pain requiring narcotic analgesics Grade IV – Obstruction/ulcer/necrosis, hematuria Chronic Genitourinary Toxicity Grade I – Microhematuria, mild telangiectasia Grade II – Increased frequency, generalized telangiectasia, intermittent gross hematuria Grade III – Severe frequency, severe telangiectasia, frequent hematuria Grade IV – Hemorrhagic cystitis, ulcer/fistula, bladder capacity <100 ml

32. Management of acute cystitis 1. Conservative/Supportive Measures Hydration: Encourage high fluid intake to dilute urine and reduce irritation. Bladder rest: Avoid irritants (caffeine, spicy food, alcohol). Urinary analgesics: Phenazopyridine or NSAIDs to manage pain. 2. Pharmacologic Management Anticholinergics: Oxybutynin , solifenacin for urgency/frequency. Alpha-blockers: Tamsulosin for obstructive symptoms.

33. Intravesical Therapies Hyaluronic acid or chondroitin sulfate : Replenish GAG layer; decrease inflammation. Antibiotics Only if superimposed bacterial infection is confirmed.

34. Management of chronic cystitis Hyperbaric Oxygen Therapy (HBOT) Gold standard for moderate-to-severe chronic radiation cystitis. Promotes angiogenesis , tissue oxygenation , and mucosal healing . Intravesical Therapies Alum instillation : Controls bleeding (coagulative action). Formalin : Reserved for refractory hemorrhagic cystitis due to severe toxicity. GAG-layer restorers: Sodium hyaluronate or PPS (pentosan polysulfate).

35. Pharmacological Management Tranexamic acid : Reduces bleeding in selected cases. Anticholinergics: Symptom relief for bladder overactivity. Anti-inflammatory agents: Corticosteroids Surgical Interventions Transurethral coagulation: For focal bleeding. Urinary diversion or cystectomy: In extreme, unresponsive cases .

36. BONE Bony pelvis is an unavoidably irradiated organ at risk (OAR) . Bones are late-responding tissues , meaning complications usually occur months to years after treatment . Chronic bone toxicity arises from progressive vascular injury and osteocyte loss , leading to fractures, osteoradionecrosis (ORN), and chronic pain . Term Definition Osteoradionecrosis (ORN) Avascular necrosis of bone caused by radiation-induced endarteritis and ischemia, leading to bone death, poor healing, and possible secondary infection. Osteopenia/Osteoporosis (RT-induced) Radiation-related decrease in bone mineral density (BMD) , predisposing to insufficiency fractures and fragility. Avascular Necrosis (AVN) Localized bone tissue death, often in femoral head , due to radiation damage to supplying vessels.

37. PATHOPHYSIOLOGY

38. FACTORS ● Radiation dose (>50 Gy) ● Cigarette smoking ● Vascular integrity ● Low BMI ● Prior fractures ● Age ● Menopausal status ● Underlying bone weakness (osteopenia or osteoporosis) ● Reirradiation ● Corticosteroid use ● Prior hormone replacement therapy

39. AVASCULAR NECROSIS Avascular Necrosis (AVN): A condition where a segment of bone dies due to loss of blood supply , leading to structural collapse, pain, and disability. Radiation-induced AVN: AVN caused by direct and indirect effects of RT , often occurring months to years after treatment . Most cases of pelvic AVN are seen when cumulative dose ≥45–50 Gy to femoral heads.

40. MANAGEMENT - Conservative management : - Analgesics (NSAIDs) - Limited weight-bearing with crutches or walker - Physiotherapy - Bisphosphonates to preserve bone density. - Hyperbaric oxygen therapy. - Core decompression surgery to relieve pressure and restore blood flow. - Bone grafting if needed. - Total hip replacement (THR) or arthroplasty. - Pain control and mobility restoration.

41. STUDIES IMPACT OF PELVIC RADIATION ON BONE MINERAL DENSITY IN CERVICAL CANCER PATIENTS BY DR JOHN SEBASTIAN M G Where he found out that bone mineral density of the non irradiated region reduced significantly in premenopausal patients whereas in post menopausal not much significant reduction.

42. REPRODUCTIVE ORGANS

43. GYNAECOLOGICAL-VAGINA ●stratified squamous epithelium ●Early vaginal injury- acute epithelial denudation with endothelial injury -> thrombosis, edema, and smooth muscle necrosis ●Delayed injury- severe fibrosis resulting in vaginal stenosis, ulceration

44. MANAGEMENT ●Necrosis- symptomatic management with antibiotics, estrogen cream, and gentle irrigation ●prevention of vaginal stenosis or shortening- encourage sexual intercourse or use of vaginal dilators ●Estrogen cream or systemic estrogen therapy.

45. Sexual Complications ●Vaginal stenosis/ shortening, dyspareunia, dryness, emotional distress ●50% women receiving pelvic RT ●Vaginal stenosis (20-88%)- within 1 year of treatment ●Radiation following surgery has the potential for causing more sexual dysfunction than radiation alone Jensen et al. evaluate 118 patients following radiation with a self-assessment question- naire. Approximately 85% had low or no sexual interest, 35% had moderate to severe lack of lubrication, 55% had mild to severe dyspareunia, and 30% were dissatisfied with their sexual life.

46. MANAGEMENT Vaginal stenosis- ●Prevention- Vaginal dilators ●Topical estrogen ●Benzydamine ●Hyperbaric O2 Vaginal dryness- ●Vaginal estrogen

47. OVARIES PATHOGENESIS :

48. Radiation Dose (Gy) Effect on Ovaries <2 Gy Minimal effect, but may still destroy up to 50% of oocytes in young women. 2–6 Gy Partial ovarian failure possible, especially in women >40 years. >6 Gy High likelihood of permanent ovarian failure in most women. >20 Gy Complete ovarian destruction almost certain, regardless of age.

49. Effect Acute Phase (during RT or shortly after) Late Phase (months to years later) Hormonal changes Temporary amenorrhea, irregular menses, decreased estrogen. Permanent ovarian failure, menopausal symptoms. Fertility impact Transient infertility possible. Permanent infertility likely at higher doses. Menstrual cycle Irregular cycles or cessation during treatment. Permanent amenorrhea. Other systemic effects None immediate. Osteoporosis, cardiovascular risk, vaginal atrophy due to estrogen deficiency.

50. Strategy Details Ovarian transposition (Oophoropexy) Surgically moving ovaries out of radiation field, usually above the pelvic brim. Shielding Custom blocks or multileaf collimators to reduce ovarian dose. Fertility preservation Oocyte or embryo cryopreservation before RT. Hormonal replacement therapy (HRT) For management of menopausal symptoms in young women without contraindications.

51. TESTIS Testes are highly radiosensitive , especially germ cells. Even low doses (0.1–0.5 Gy) can cause temporary suppression of spermatogenesis. Permanent sterility occurs at doses >4–6 Gy , while Leydig cells are preserved until >20 Gy . Sperm banking before RT is the standard of care for men undergoing pelvic or total body irradiation. Testicular shielding and advanced RT techniques are essential to minimize damage.

52. Grade Description Grade 0 No visible change from baseline. Grade 1 Faint erythema or dry desquamation; epilation, decreased sweating. Grade 2 Moderate to brisk erythema; patchy moist desquamation (mostly in skin folds); moderate edema. Grade 3 Confluent moist desquamation (beyond skin folds); pitting edema. Grade 4 Ulceration, hemorrhage, or necrosis of skin. DERMATITIS DERMATOLOGICAL COMPLICATIONS

53. Acute Skin Reactions Occur during or shortly after RT (usually within 2–3 weeks of starting treatment). Erythema : redness, warmth due to capillary dilatation. Dry desquamation: peeling and flaking of the epidermis with itching. Moist desquamation: epidermal breakdown with oozing/ulceration, usually in skin folds (groin, perineum, gluteal cleft). Edema: due to capillary permeability changes. Pain, burning, pruritus: may limit mobility or cause discomfort.

54. Chronic Skin Reactions Can appear months to years after pelvic RT. Skin atrophy: thinning, fragile skin. Telangiectasia : dilated superficial vessels giving a reddish/purplish discoloration. Pigmentation Hyperpigmentation (increased melanin deposition). Hypopigmentation (loss of melanocytes in high-dose areas). Fibrosis and induration: thickening and stiffness of subcutaneous tissues. Ulceration and poor wound healing: due to vascular compromise and fibrosis. Radiation dermatitis (chronic): persistent skin inflammation, dryness, itching. Secondary skin cancers (rare, long-term): basal cell carcinoma, squamous cell carcinoma in irradiated field.

55. Management Acute Reactions: Erythema/dry desquamation: Mild topical corticosteroids, aloe vera, emollients. Oral antihistamines for itching. Moist desquamation: Non-adherent dressings, hydrocolloid dressings. Saline compresses to clean area. Topical antibiotics if secondary infection.

56. Chronic Reactions: Pigmentation/telangiectasia: usually cosmetic, laser therapy. Fibrosis: physiotherapy, massage, sometimes pentoxifylline + vitamin E. Ulceration: surgical debridement, flap coverage if severe. Secondary malignancies: long-term dermatologic surveillance.

57. Hematological Complications Lymphopenia Most radiosensitive cell line – declines with doses as low as 0.3 Gy. Appears within days of RT. Leads to immunosuppression → ↑ risk of viral, fungal, and opportunistic infections. Granulocytopenia (Neutropenia) Occurs with larger doses or concurrent chemoradiation. Increases risk of sepsis and hospitalization. Thrombocytopenia Reduced platelet counts → mucosal bleeding, petechiae, epistaxis, hematuria. More common when RT is combined with chemotherapy.

58. Anemia Suppression of erythroid progenitors. Exacerbated by hematuria, GI bleed, chronic disease, or nutritional deficiency. Contributes to fatigue, dyspnea, poor radiosensitization (tumor hypoxia). Pancytopenia Seen when large pelvic volumes are irradiated (e.g., whole pelvis + paraaortic RT). Worsened by concurrent cisplatin-based chemoradiation. Long-term complications Rare, but include myelodysplastic syndrome (MDS) and secondary leukemia due to mutagenic effects of radiation on marrow stem cells (usually years later).

59. Bone Marrow Suppression Stem cells are highly radiosensitive. Doses as low as 0.3 Gy → reduction in lymphocytes. Progression of cytopenias: Lymphopenia → Granulopenia → Thrombopenia → Anemia. Dose-response: larger volumes of irradiated marrow → more severe suppression. Sites at risk: pelvis, spine, sternum (contain large proportion of active marrow).

60. Management Monitoring Weekly CBCs during RT (more frequent if on chemoradiation). Supportive Measures Hold chemotherapy when: Neutrophils < 1500/µL Platelets < 100,000/µL Withhold RT when: Neutrophils < 500–1000/µL

61. Transfusions: Maintain hemoglobin > 10 g/dL Platelets transfused if <10–20,000/µL or with active bleeding Drugs Growth factors: G-CSF (filgrastim) for neutropenia. Erythropoietin (EPO) for selected cases of anemia (not routine in curative RT). Antibiotics/antifungals/antivirals: prophylaxis or treatment of infections. Infections B road-spectrum antibiotics started promptly in febrile neutropenia. Nutrition & Support Adequate protein, iron, folate, and vitamin B12 supplementation. Hydration, rest, and symptom management.

62. A study was done by Dr Raghavendra to find out the correlation of hematologic toxicities with the bone marrow radiation dose and volume during concurrent chemoradiation in patient with cervical cancer and observed that out of 25 patients 12 patients had grade 2 anemia and 2 patients had grade 1 anemia and no toxicity with wbc and platelets.

63. Organ / Structure Toxicity Constraints Incidence at Threshold Dose Notes / QUANTEC Guideline Rectum Grade ≥2 late rectal toxicity (bleeding, urgency, diarrhea) D 50 <50Gy 15–20% Keep mean rectal dose <50 Gy Small Bowel Acute enteritis (diarrhea, cramps) V45 <195 cc 10–15% Dose-volume driven toxicity Bladder Grade ≥2 acute cystitis D50 <35 Gy 15–20% Frequency, urgency, dysuria Femur Avascular necrosis (AVN) / fracture D15<30Gy 5%

64. Ovary Permanent ovarian failure (young women <40 yrs) >6 Gy >90% Ovarian transposition recommended Older women (>40 yrs) >14 Gy >90% Sensitivity decreases with age Testis (Scatter dose) Temporary suppression of spermatogenesis 0.1–1 Gy Nearly 100% temporary suppression Recovery if dose <2 Gy Permanent sterility >4–6 Gy >90% Leydig cell dysfunction >20 Gy 50–80% Causes hypogonadism Skin Acute dermatitis (Grade 2) >20 Gy 30–40% Erythema, dry desquamation Moist desquamation (Grade 3) >40 Gy 10–15% Usually in skin folds Chronic fibrosis >40 Gy 20–30% Progressive, irreversible Lymphatics Lymphedema (lower limb / genitalia) Mean dose >40–45 Gy 10–15% Often combined with nodal dissection

65. Tissue / Effect Threshold Dose (Gy) Spermatogenesis suppression 0.1–1 Gy Permanent male sterility >4–6 Gy Ovarian failure (young women) >6 Gy Femoral head necrosis >44–45 Gy Chronic rectal toxicity >50 Gy Bladder toxicity >55 Gy Acute marrow suppression >20 Gy

66. Thank you