Anal, Pancreatic, and Esophageal Cancer: Symptoms, Stages, and Treatment

Posted on Jan 5, 2025 in Physical Education

Anal Canal Cancer

Natural History

Initially, local growth is in the anal wall depth. In advanced situations, increased depth can affect adjacent organs. Lymph node spread is towards the internal perirectal and iliac lymph nodes, and the inguinal lymph nodes. The incidence can be correlated with tumor size, and it is rare at the moment of diagnosis.

Pathological Classification

The most frequent tumors are squamous cell carcinomas. Adenocarcinomas are less common. Small cell carcinomas, lymphomas, and melanomas can also occur.

T Classification

  • Tx: Tumor cannot be assessed
  • T0: No evidence of primary tumor
  • Tis: Carcinoma in situ
  • T1: Tumor 2 cm or less in greatest dimension
  • T2: Tumor more than 2 cm but not more than 5 cm
  • T3: Tumor more than 5 cm
  • T4: Tumor of any size invades adjacent organs (e.g., vagina, urethra, bladder)

N Classification

  • Nx: Regional lymph nodes cannot be assessed
  • N0: No regional lymph node metastasis
  • N1: Metastasis in perirectal lymph node(s)
  • N2: Metastasis in unilateral internal iliac or inguinal lymph node(s)
  • N3: Metastasis in perirectal and inguinal lymph nodes and/or bilateral internal iliac and/or inguinal lymph nodes

Stage Classification

  • Stage 0: Tis, N0, M0
  • Stage I: T1, N0, M0
  • Stage II: T2 or T3, N0, M0
  • Stage IIIa: T1 or T2 or T3, N1, M0
  • Stage IIIb: T4, N1, M0
  • Stage IV: Any T, any N, M1

General Oncologic Treatment

  • Surgery: Radical abdominoperineal resection with permanent colostomy. This can achieve survival rates greater than 70% after 5 years. If recurrences appear after radical surgery, radiotherapy (RT) treatments are performed.
  • If we want to perform conservative surgery (anal sphincter preservation), treatments with RT at a dose of 60Gy or more are performed. Similar survival rates are obtained, but there is a risk of fibrosis and necrosis of the anal sphincter.
  • Chemotherapy (QT) + RT: Better results are obtained than with RT alone. In these cases, surgery is only performed if there are no recurrences.

Stage I and II

Small tumors without sphincter involvement can be treated with local excision. The rest of Stage I (with sphincter involvement or larger) may have local excision with or without adjuvant RT or QT. If the tumor remains after RT/QT, it can be eliminated using brachytherapy (BQ). Radical surgery is reserved for cases of persistence after RT or tumor recurrence.

Stage III

RT + QT or radical surgery + iliac and inguinal lymphadenectomy + postoperative RT.

Stage IV

Due to the poor prognosis of these patients, they should be included in clinical trials. The options would include:

  • Palliative surgery
  • Palliative RT
  • Palliative RT + QT

Target Volume

The tumor and internal iliac and inguinal lymph node chains.

Treatment Simulation

  • Radical Treatment: Anteroposterior-Posteroanterior-Laterals.
  • Protection of iliac crests must be taken into account.
  • To give the total dose to the inguinal lymph nodes, the posteroanterior field must be complemented with 2 previous inguinal fields (right and left) with electrons.
  • Radical Treatment: 36Gy are administered to the primary tumor and lymph node chains, and subsequently, a boost is applied to the primary tumor, reaching 45Gy. If the tumor persists at this dose, the boost is continued up to 51Gy. If only RT is performed, 45Gy is applied to the target volume and a boost of 65Gy to the primary tumor.

Pancreatic Cancer

Notable Vessels, Nerves, and Lymphatics in Pancreatic Cancer

  • Arteries: Splenic, superior pancreaticoduodenal, and inferior pancreaticoduodenal. All the branches surround the gland (pancreas), forming the peri-pancreatic circle.
  • Veins: Superior mesenteric vein, splenic vein, and portal vein.
  • Lymphatics: Lymph node groups are situated parallel to the splenic vessels and superior mesenteric nerves, parallel to the circulating vessels.

Pathological Classification

90% of the tumors are adenocarcinomas, and 75% are located in the head of the pancreas.

T, N, M Classification

  • T1: Tumor limited to the pancreas, 2 cm or less in greatest dimension
  • T2: Tumor limited to the pancreas, more than 2 cm in greatest dimension
  • T3: Tumor that invades the duodenum, bile duct, or peripancreatic tissue
  • T4: Tumor invades the stomach, spleen, colon, or adjacent large vessels
  • N1: Regional lymph node involvement
  • M: Same as before (distant metastasis)

Stage Classification

  • Stage 0: Tis, N0, M0
  • Stage I: T1 or T2, N0, M0
  • Stage II: T3, N0, M0
  • Stage III: T1, T2, or T3, N1, M0
  • Stage IVA: T4, any N, M0
  • Stage IVB: Any T, any N, M1

Oncologic Treatment

  • Stage I and II: The technique used is pancreaticoduodenectomy, resection of the head of the pancreas and duodenum. There is an operative mortality of 10%. Postoperative treatment with QT and RT is given.
  • Stage III: This stage does not allow surgery, and techniques such as RT and QT are normally palliative (for pain, gastric obstruction, and jaundice).
  • Stage IV: Fatal prognosis. Only palliative treatments, which may be surgery, RT, or QT.

Prognosis and Results

In selected patients with small tumors without lymph node involvement, 5-year survival rates of 25% can be achieved with surgery and free resection margins. Under normal conditions, the 5-year survival rate is 4.4%. In patients with a fatal prognosis, it is between 3-4 months, and palliative RT should be given.

Follow-up

  • Imaging Tests: Ultrasound, CT, MRI of the abdomen
  • Tumor Markers: CA 19.9, CEA

Esophageal Cancer

Histologic Classifications

  1. Epidermoid Carcinoma: Originates in the lining epithelium of the esophagus. They account for 90% of all esophageal cancers. Related to alcohol and tobacco abuse.
  2. Adenocarcinoma: Arises in the esophageal cells, mucosal or submucosal. They usually arise on Barrett’s esophagus.

Gross Classification

  1. Polypoid or Vegetans: Irregular shape, usually mammillated and ulcerated in the center.
  2. Ulcerated: 25% of cases. Presents loss of substance of variable depth and oval shape. The edges of the ulcer are often raised.
  3. Infiltrating: 15% of cases. Thickening of the wall. It grows through the submucosa.
  4. Mixed: Any combination.

Distribution of the Different Sections of the Esophagus and Incidence

  • Cervical Esophagus: From the throat to the supraclavicular area.
  • Thoracic Esophagus: Divided into three parts:
    • Upper Third: From the supraclavicular area to the tracheal bifurcation (carina). Incidence: 12%.
    • Middle Third: From the carina to the midpoint. Incidence: 50%.
    • Lower Third: From the previous midpoint to the cardia. Incidence: 23%.

Local Extension

  • Surface Extension in the Submucosa: 20% of multicentric tumors appear (foci separated by more than 5 cm).
  • Depth Extension: It extends through the wall by invasion and then to the periesophageal tissue and neighboring organs.
  • Lymphatic Extension: Often early, even in tumors limited to the mucosa. The most commonly affected lymph nodes are:
    • Cervical lymph nodes
    • Tracheal and bronchial lymph nodes
    • Mediastinal lymph nodes
    • Upper abdomen lymph nodes

Nodal Extension

  • Tumors of the Upper Third: Nodal area extends to the supraclavicular, mediastinal, and subdiaphragmatic regions.
  • Tumors of the Middle Third: Same as above, but little supraclavicular involvement.
  • Tumors of the Lower Third: Same as the middle third.

Distant Extension

(Especially to the lung and liver)

  • The wall of the esophagus is drilled, and neighboring organs are invaded. The most common are the trachea, bronchi, larynx, and thyroid gland.
  • In advanced cases, it can spread to the liver, lungs, bones, and kidneys.

Clinical Rating

  • Operable cases
  • Inoperable cases

The assignment to one of these two groups depends on the criteria of each team. Some inoperability criteria are:

  • Tracheobronchial invasion
  • Recurrent laryngeal nerve paralysis
  • Invasion of non-resectable structures
  • Supraclavicular nodal mass

TNM Classification

  • T:
    • T1: Tumor invades mucosa or submucosa
    • T2: Tumor invades muscularis propria
    • T3: Tumor invades adventitia
    • T4: Tumor invades adjacent structures
  • N:
    • Nx: There is no evidence of lymph node involvement
    • N0: No palpable homolateral axillary lymph nodes
    • N1: Movable homolateral axillary lymph nodes
    • N2: Homolateral axillary lymph nodes fixed to each other or other structures
    • N3: Metastasis in homolateral internal mammary lymph nodes
  • M:
    • Mx: Cannot be assessed
    • M0: No distant metastasis
    • M1: Distant metastasis, including homolateral supraclavicular lymph nodes

Stage Classification

  • Stage 0: Tis, N0, M0
  • Stage I: T1, N0, M0
  • Stage IIA: T2-T3, N0, M0
  • Stage IIB: T1-T2, N1, M0
  • Stage III: T3-T4, N1, M0
  • Stage IV: Any T, any N, M1

General Oncologic Treatment

  • The operability rate is 30%.
  • Results are mediocre in operated patients.
  • Survival is not much higher in inoperable patients.
  • Better prognosis with the association of RT + QT.

Treatment of Operable Cancers

  • Esophagectomy
  • QT or RT does not improve survival.
  • Preoperative RT-QT is being tested, applying 40Gy and performing surgery between the 3rd and 6th week.

Treatment of Inoperable Cancers

  • Exclusive RT: Reference treatment.
  • RT + QT: Better results than RT alone.

Contraindications for Surgery

Some inoperability criteria are:

  • Tracheobronchial invasion
  • Recurrent laryngeal nerve paralysis
  • Invasion of non-resectable structures
  • Supraclavicular nodal mass